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Sample records for british experimental pile operation

  1. Development of gas cooled reactors and experimental setup of high temperature helium loop for in-pile operation

    Energy Technology Data Exchange (ETDEWEB)

    Miletić, Marija, E-mail: marija_miletic@live.com [Czech Technical University in Prague, Prague (Czech Republic); Fukač, Rostislav, E-mail: fuk@cvrez.cz [Research Centre Rez Ltd., Rez (Czech Republic); Pioro, Igor, E-mail: Igor.Pioro@uoit.ca [University of Ontario Institute of Technology, Oshawa (Canada); Dragunov, Alexey, E-mail: Alexey.Dragunov@uoit.ca [University of Ontario Institute of Technology, Oshawa (Canada)

    2014-09-15

    Highlights: • Gas as a coolant in Gen-IV reactors, history and development. • Main physical parameters comparison of gas coolants: carbon dioxide, helium, hydrogen with water. • Forced convection in turbulent pipe flow. • Gas cooled fast reactor concept comparisons to very high temperature reactor concept. • High temperature helium loop: concept, development, mechanism, design and constraints. - Abstract: Rapidly increasing energy and electricity demands, global concerns over the climate changes and strong dependence on foreign fossil fuel supplies are powerfully influencing greater use of nuclear power. In order to establish the viability of next-generation reactor concepts to meet tomorrow's needs for clean and reliable energy production the fundamental research and development issues need to be addressed for the Generation-IV nuclear-energy systems. Generation-IV reactor concepts are being developed to use more advanced materials, coolants and higher burn-ups fuels, while keeping a nuclear reactor safe and reliable. One of the six Generation-IV concepts is a very high temperature reactor (VHTR). The VHTR concept uses a graphite-moderated core with a once-through uranium fuel cycle, using high temperature helium as the coolant. Because helium is naturally inert and single-phase, the helium-cooled reactor can operate at much higher temperatures, leading to higher efficiency. Current VHTR concepts will use fuels such as uranium dioxide, uranium carbide, or uranium oxycarbide. Since some of these fuels are new in nuclear industry and due to their unknown properties and behavior within VHTR conditions it is very important to address these issues by investigate their characteristics within conditions close to those in VHTRs. This research can be performed in a research reactor with in-pile helium loop designed and constructed in Research Center Rez Ltd. One of the topics analyzed in this article are also physical characteristic and benefits of gas

  2. British Energy Operating Experience Programme

    International Nuclear Information System (INIS)

    British Energy is the major nuclear generator in the U.K. It has a market share varying between 22% and 25% of the total U.K. generation. The fleet of power stations operated by British Energy consists of one 1250 MWe Pressurised Water Reactor, six Advanced Gas Cooled reactor sites, each with two reactor units of 660 MWe, and one coal fired site with four units of 500 Mwe. In early 1999 British Energy set a strategic goal, for all its reactor units, to achieve 'World Class Performance through Cost leadership' by the end of year 2004. This would be measured against the applicable Upper Quartile performance indicators of the World Association of Nuclear Operators (WANO). Against this strategic goal six fundamental objectives were identified, one of which was to define, deploy and measure the effectiveness of a world class Operating Experience programme. British Energy has clearly re-defined its Operating Experience programme and, recognised the value of learning from Operating Experience. Commitment to the programme, and communicating the value of an effective OE programme is being clearly demonstrated by all managers throughout the organisation. Making the information easily accessible at the workplace has been achieved via the British Energy intranet, the harder step is to ensure OE is consulted before commencing an assigned task or plant evolution. Early signs of this are encouraging, but a continuous sustained effort will be required for probably the next two years. The full deployment of the OE programme is scheduled to be complete by 2004. There will however be a redefined programme identified by then to incorporate the lessons learnt and to ensure the programme is aligned with the business as it evolves. An analysis of event root causes and precursors since May 2001 will be undertaken in June 2002. These will be compared with data from previous years to ascertain the effect on the number of recurring events. The critical question, 'has this prevented recurring

  3. Analysis of the Effect of Pile Skin Resistance Verses Pile Diameter Based on Experimental Research

    Directory of Open Access Journals (Sweden)

    S. M. Marandi

    2009-01-01

    Full Text Available In spite of the many recent advances in pile design and execution methods, the quantitative effects of grouted pile skin resistance and form on subsequent pile behavior remains an area for research. There are many parameters involved in the analysis of the bearing capacity of piles and descriptive method theory of the loading effect for each parameter is very complex. Many of these parameters are interrelated and investigation of the relationships leads to complex equations, which cannot be easily solved. The only reliable solution is to study the influence of each parameter by experimental model tests in equipped laboratories. This research presents the results of static compression tests on two model groups of pipe and grouted pile shafts (35mm, 50mm and 60 mm in diameters and 900 mm in length installed into beds of Yazd siliceous sand (located in southeast Iran. The findings of the experimental research were to the average ultimate loads at failure for grouted piles were approximately 12% higher than for the pipe piles. The pile skin resistance is an effective factor on pile bearing capacity, the load transfer response appears to be more plastic with increasing pile diameter in siliceous sand and the skin resistance of the pile was not linearly proportional to the pile diameter and varied with increase in pile diameter.

  4. Experimental study on pile-end post-grouting piles for super large bridge pile foundations

    Institute of Scientific and Technical Information of China (English)

    Weiming GONG; Guoliang DAI; Haowen ZHANG

    2009-01-01

    The application of pile-end post-grouting piles for super-large bridge pile foundations in some important projects was introduced in this paper. There are totally 21 test piles. The maximum pile diameter varies from 2.5 m to 3 m, and the maximum length is 125m; the bearing capacity of the post-grouting piles is over ten thousands tons. Based on the test results, the bearing capacity,displacement, and beating characteristics before and after grouting were analyzed. The results show that the beating capacity of the piles is increased in different degrees after grouting although the technical parameters, including the patterns of grouting pipes, pressure, dosages of cement, duration of grouting lasting time, are different. However,the obtained values are very discrete. In addition, the calculation formula for the post-grouting piles under specified grouting condition was deduced based on the statistics analysis results of 57 test piles. The research results have been applied in the design of bridge foundation.

  5. Seismic soil pile interaction:experimental evidence

    OpenAIRE

    Moccia, Flaviana

    2009-01-01

    The comprehension of the real behaviour of pile foundations under earthquake loading is very important, since it can significantly affect the performance of the superstructure. As a matter of fact the experience of recent earthquake has confirmed that piles can suffer extreme damage and failure under earthquake loading. The case histories from Kobe earthquake (1995) indicate that not only the inertial actions but also the kinematic ones, due to ground movements, which was overlooked in design...

  6. Experimental Investigation of the Effectiveness of Various  Additives in Reducing Wind Erosion from Iron Ore Piles 

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Hassanvand

    2012-10-01

    Full Text Available Background and Objectives: Wind-induced particulate air pollution from iron ore piles can causes environmental and economic problems for steel industries. In this experimental study, the effectiveness of various additives in reducing particulate air pollution from iron ore piles was investigated in a laboratory wind tunnel.Materials and Methods:  The experimental set up consisted of a prismatic pile and a wind tunnel. Four different wind speeds of 4.3, 5, 7 and 11 m/s was used in the study  Municipal water, quick lime (2%, seawater, treated industrial wastewater and Polylatice (0.25% were used as additives to stabilize the upper layer of the pile. Results: Emission factors for non-stabilized (without additive piles at 4.3, 5, 7 and 11 m /s wind speeds were 46.7, 73.2, 1025.4 and 13768.7 g/m2, respectively. Stabilized piles with 2.6, 2.7, 2.8, 2.7 and 2.8 percent additive (moisture content of the upper layer of the pile for municipal water, Polylattice (0.25%, treated industrial wastewater, seawater and quick lime (2% indicated a decrease of 99.4%, 100%, 99.3%, 99.5% and 99.5% particulate emission reduction, respectively. Conclusions: Proper selection and use of additives on iron piles has the potential for decreasing  more than 99% of the wind-induced particulate emissions. Operational factors such as covered area, spray frequency, pile geometry, seasonal adjustments related to ambient temperature and humidity, wind speed and operator training need to be an integral part of the pollutant reduction program.              

  7. An Experimental Study on Pile Spacing Effects under Lateral Loading in Sand

    Directory of Open Access Journals (Sweden)

    Mahdy Khari

    2013-01-01

    Full Text Available Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand.

  8. Experimental Comparison of Non-Slender Piles under Static Loading and under Cyclic Loading in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo

    2012-01-01

    An experimental evaluation of the pile behavior of non-slender piles exposed to static and cyclic lateral loading is presented. The tests were conducted in a pressure tank at Aalborg University. This enabled the possibility of applying an overburden pressure to the soil. When conducting small...

  9. Experimental study on load bearing behavior of large-scaled caps with pile groups

    Institute of Scientific and Technical Information of China (English)

    Guo Chao; Lu Bo; Gong Weiming; Qiu Hongxing

    2009-01-01

    The objective of this investigation was to study the behavior of deep pile caps and the ultimate load-carrying capacity. Four 1/10 scaled models of nine-pile caps were cast and tested on vertical loads to failure. The destruction shapes of pile caps, the correlation between load and displacement, and the internal stresses were analyzed systematical-ly. The results demonstrated that the failures of all the four models are resulted from punching shear; the internal flow of the forces in nine-pile caps can be approximated by "strut-and-fie" model. Furthermore, the failure loads of these spec-imens were predicted by some of the present design methods and the calculated results were compared with the experi-mental loads. The comparative results also indicated that the "strut-and-tie" model is a more reasonable design method for deep pile caps design.

  10. British Columbia Power Export Corporation: Operational review for operating year, October 1989 to September 1990

    International Nuclear Information System (INIS)

    The British Columbia Power Export Corporation (POWEREX) is a wholly owned subsidiary of British Columbia Hydro, established in 1988 as the single agency responsible for implementing the provincial policy of international electricity trade. POWEREX objectives are to conduct long term firm electricity trade utilizing private sector financing, operating capabilities, and generating sources. Short term electricity transactions are handled by the part of POWEREX called the Powerex Pool Operation. An operational review of POWEREX for 1989-90 is presented, giving information on export contracts, license approvals, export sales negotiations, pool operation revenues and sales, British Columbia Hydro generation and integrated system performance, and operational planning. 15 figs

  11. CONDUCTING AND ANALYZING THE RESULTS OF THE EXPERIMENTAL BOX TEST OF RETAINING WALL MODELS WITHOUT PILES AND ON THE PILE FOUNDATION

    Directory of Open Access Journals (Sweden)

    M. A. Lisnevskyi

    2015-08-01

    Full Text Available Purpose. Taking into consideration that the bearing capacity of the foundation may be insufficient, in the study it is assumed that pile foundation can be used to reduce the impact of the construction of new retaining structures on roads and railways near the existing buildings or in areas of dense urban development and ensure the stability of the foundation. To reduce the volume of excavation it is necessary to choose the economic structure of the retaining wall. To do this, one should explore stress-strain state (SSS of the retaining walls, to develop methods to improve their strength and stability, as well as to choose the most appropriate method of their analysis. Methodology. In the design of retaining walls foundation mat and piles are considered as independent elements. Since the combined effect of the retaining wall, piles and foundation mat as well as the effect of soil or rock foundation on the structure are considered not fully, so there are some limitations in the existing design techniques. To achieve the purpose the box tests of retaining walls models without piles and with piles for studying their interaction with the surrounding soil massif were conducted. Findings. Laboratory simulation of complex systems «surrounding soil – retaining wall – pile» was carried out and on the basis of the box test results were analyzed strains and its main parameters of the stress-strain state. Analysis of the results showed that the structure of a retaining wall with piles is steady and stable. Originality. So far, in Ukraine has not been carried out similar experimental box tests with models of retaining walls in such combinations. In the article has been presented unique photos and test results, as well as their analysis. Practical value. Using the methodology of experimental tests of the retaining wall models with piles and without them gives a wider opportunity to study stress-strain state of such structures.

  12. Marijuana growing operations in British Columbia revisited, 1997-2003

    Energy Technology Data Exchange (ETDEWEB)

    Plecas, D.; Malm, A.; Kinney, B. [University College of the Fraser Valley, Abbotsford, BC (Canada). Dept. of Criminology and Criminal Justice]|[University College of the Fraser Valley, Abbotsford, BC (Canada). International Centre for Urban Research Studies

    2005-03-01

    The results of a comprehensive study of marihuana cultivation in British Columbia were presented. This report describes the incidents of marihuana grow operations coming to the attention of the police; the characteristics of marihuana growing operations; the suspects involved; the actions taken by the police and courts; and penalty. The study confirms that these operations which are dispersed throughout the province are increasing in both size and sophistication. The average number of kilograms of harvested marihuana seized per grow operation tripled from 1997 to 2003. In addition, the number of high intensity lights seized per operation also grew, leading to an associated increase in the average amount of electricity theft per operation. About 1 in 5 grow operations involved hydro theft. The average cost associated with hydro theft per operation was about $2,880 in 1997 and $3,740 in 2003. In 2003, it is estimated that growers stole more than $3,200,000 from BC Hydro. In addition to electricity by-passes, 15 per cent of indoor grow operations contained hazards such as weapons, explosives, and other drugs. 25 tabs., 34 figs.

  13. Experimental Modeling of Pile-Leg Interaction in Jacket Type Offshore Platforms Cyclic Inelastic Behavior

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    M. R. Honarvar

    2008-01-01

    Full Text Available Offshore platforms in seismically active areas should be designed to survive in the event of severe ground excitations with no global structural failure. The annulus between the pile and leg in jacket-type offshore platforms can be filled with cement grout as a means of reducing horizontal deflections, inhibiting corrosion and preventing local damages. This paper discusses an experimental approach which can be used to demonstrate the effect of grouting on enhanced structural performance of jackets. In this regard, the lateral load bearing behavior of grouted and un-grouted jackets are investigated experimentally with special attention to effect of grout on pile-leg interaction. Results are presented on the cyclic inelastic behavior of two scaled frame models of a representative platform which was recently installed in the Persian gulf. The objective of this effort was to improve the understanding of the behavior of jackets subjected to lateral motions and specially the effects of exact real pile-leg interaction. it should be noted that this paper addresses the exact and realistic pile-leg interaction. It is concluded that grouting can not be considered as a definite method of improving strength and structural nonlinear dynamic behavior. Although it generally increases the lateral stiffness, but some side effects and points are to be considered. In this paper, the two separate lateral load bearing mechanisms -namely portal (braced mechanism and frame bending mechanism- are distinguished and the effect of grout on each one is shown.

  14. EXPERIMENTAL AND NUMERICAL ASSESSMENT OF DYNAMIC SOIL-PILE-STRUCTURE INTERACTION

    OpenAIRE

    Durante, Maria Giovanna

    2015-01-01

    A reliable approach for studying the seismic soil-pile- structure interaction is the physical modelling of scaled models in 1-g or n-g devices. A comprehensive laboratory test campaign, performed on the 6-degree-of-freedom 1-g shaking table of the Bristol Laboratory for Advanced Dynamics Engineering (BLADE) of the University of Bristol (UK), is illustrated and discussed in the present thesis. The experimental campaign was carried out within the framework of the Seismic Engineering Research In...

  15. Experimental Study on Post Grouting Bearing Capacity of Large Diameter Bored Piles

    Directory of Open Access Journals (Sweden)

    Wang Duanduan

    2015-01-01

    Full Text Available Post grouting can improve the inherent defects such as the formation of the mud cake at pile side and the sediment at pile end in the process of bored pile construction. Thus post grouting has been widely used in Engineering. The purpose of this paper is to research the influences of post grouting to pile bearing capacity more systematically and intuitively. Combined with the static load test of four test piles in Weihe River Bridge test area of new airport highway in Xi’an, the bearing capacity and settlement of routine piles and post grouting piles are comparatively analyzed. The test results show that under the same geological condition, post grouting can improve the properties of pile tip and pile shaft soil of bored piles significantly, enhance the ultimate resistance, improve the ultimate bearing capacity and reduce the pile tip settlement. Then post grouting can aim to optimize pile foundation.

  16. Experimental Investigations of Tension Piles in Sand Subjected to Static and Cyclic Loading

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    The present thesis regards the behavior of the piles in jacket pile foundations used for offshore wind turbines. The piles are often loaded in tension because of the combination of wind and wave conditions and the low self-weight of the wind turbine. The repeated cyclic loading can lead...... to accumulated upwards displacement of the piles and, thus, undesired deflection of the wind turbine structure. This study concerns the effect of cyclic loading on a pile installed in dense sand and loaded in tension. A new laboratory test setup was constructed to make these pile load tests. The thesis discusses...... the advantages and disadvantages of the test setup. The results of cyclic loading tests showed that the loading conditions are very important for the behavior of piles. Some wind and wave conditions can be beneficial and increase the pile capacity while other conditions can be damaging and reduce the pile...

  17. Experimental study on DX pile performance in frozen soils under lateral loading

    Institute of Scientific and Technical Information of China (English)

    XiaoBing Liu; LiHong Chen; ZhongYang Yu; JianXiao Hu; Wen Peng

    2013-01-01

    Experiments about working mechanism and mechanical characteristics of the DX model pile foundation under lateral dynamic and static loading were conducted by using a model system of the dynamic frozen soil-pile interaction. The horizontal displacement-force relationship of the pile head and bending moment distribution along the body in frozen soils of different temperatures were discussed. According to test results, both the horizontal displacement-force relationship of the DX pile head and bending moment distribution of the DX pile body are smaller than that of equal-diameter piles under same lateral loads. The piles with different plate positions show different displacements and bending moments. This phenomenon is mainly related to the soil temperature and bearing plates locations. Thus, dynamic response analysis of the pile foundation should be taken into account.

  18. Experimental assessment of the insertion loss of an underwater noise mitigation screen for marine pile driving

    NARCIS (Netherlands)

    Jansen, H.W.; Jong, C.A.F. de; Jung, B.

    2012-01-01

    Because of the concern about potential effects on marine pile driving, the industry is developing silent marine pile driving concepts. One of the new concepts, which has been engineered by IHC Hydrohammer in the Netherlands, is the application of a steel Noise Mitigation Screen (NMS) around the pile

  19. Experimental analysis of the inertial soil-pile interaction in the centrifuge

    OpenAIRE

    CHENAF, N; CHAZELAS, JL; Escoffier, S.

    2006-01-01

    The soil-pile dynamic interaction is studied through centrifuge tests. In this paper, we focus on the inertial effect as a first step to knowledge the seismic behaviour of the soil-pile system. A single shock test, applied at the head of a flexible single pile, is used to simulate an impact on bridge piers ; successive shocks are also used to simulate boat impacts on harbour facilities. To improve the understanding of the inertial soil-pile interaction, a comparison of pile response to both l...

  20. Experimental Study on Post Grouting Bearing Capacity of Large Diameter Bored Piles

    OpenAIRE

    Wang Duanduan; Wang Longfei; Zhang Lipeng

    2015-01-01

    Post grouting can improve the inherent defects such as the formation of the mud cake at pile side and the sediment at pile end in the process of bored pile construction. Thus post grouting has been widely used in Engineering. The purpose of this paper is to research the influences of post grouting to pile bearing capacity more systematically and intuitively. Combined with the static load test of four test piles in Weihe River Bridge test area of new airport highway in Xi’an, the bearing capac...

  1. Experimental Research on Large Diameter Cast-in-Place Piles Embedded in Rock

    Institute of Scientific and Technical Information of China (English)

    衡朝阳; 何满潮; 姚爱军

    2001-01-01

    This paper expatiated the field test of large diameter cast-in-place piles embedded in soft rock, including static loading test, high or low strain dynamic test, measurement of stresses and strains of pile body, and pressure measurements between pile tip and soft rock. The relative in-situ test problems are discussed. Based on the limit equilibrium theory and the load transfer equation, a synthesis method of analyzing the ultimate carrying capacity of single large diameter pile is put forward. The research results show that the key to determining the ultimate carrying capacity of single pile with a large diameter is the analysis of the intensity of soft rock.

  2. Experimental study on settlement of model piles in frozen soil under dynamic loading

    Institute of Scientific and Technical Information of China (English)

    张建明; 朱元林; 张家懿

    1999-01-01

    Test results show that the settlement process of model piles is mainly the rheological process of frozen soil under shear loading. The settlement rate of model piles increases with increasing temperature of frozen soil, decreasing roughness of pile surface and increasing rigidity of pile foundation. As the water content of frozen soil reaches its saturation value, the settlement rate is the least. When the level of loading is higher, the settlement rate under dynamic loading is less than that under static loading. With the level of loading lowering, the effect between dynamic and static loading on the settlement rate becomes close gradually. Under the present test conditions, the settlement rate of model piles is independent of the frequency of dynamic loads.

  3. The Relationship between Basic Skills and Operational Effectiveness in the British Army

    Science.gov (United States)

    Swain, Jon

    2015-01-01

    This paper draws on data that formed part of a major three-year longitudinal study (2008-2011), which set out to investigate basic skills (BS) provision and needs in the British army and its relationship to operational effectiveness. Using mixed methods, the findings draw on qualitative data from 60 semi-structured interviews with 26 young…

  4. Simulation of Granular Flows and Pile Formation in a Flat-Bottomed Hopper and Bin, and Experimental Verification

    Directory of Open Access Journals (Sweden)

    Shinichi Yuu

    2011-08-01

    Full Text Available Granular flows of 200 μm particles and the pile formation in a flat-bottomed hopper and bin in the presence of air and in a vacuum were predicted based on three-dimensional numerically empirical constitutive relations using Smoothed Particle Hydrodynamics and Computational Fluid Dynamics methods. The constitutive relations for the strain rate independent stress have been obtained as the functions of the Almansi strain including the large deformation by the same method as Yuu et al. [1]. The constitutive relations cover the elastic and the plastic regions including the flow state and represent the friction mechanism of granular material. We considered the effect of air on the granular flow and pile by the two-way coupling method. The granular flow patterns, the shapes of piles and the granular flow rates in the evolution are compared with experimental data measured under the same conditions. There was good agreement between these results, which suggests that the constitutive relations and the simulation method would be applicable for predicting granular flows and pile formation with complex geometry including free surface geometry. We describe the mechanisms by which the air decreases the granular flow rate and forms the convergence granular flow below the hopper outlet.

  5. Experimental and Analytical Investigations of Piles and Abutments of Integral Bridges

    OpenAIRE

    Arsoy, Sami

    2000-01-01

    Bridges without expansion joints are called "integral bridges." Eliminating joints from bridges crates concerns for the piles and the abutments of integral bridges because the abutments and the piles are subjected to temperature-induced cyclic lateral loads. As temperatures change daily and seasonally, the lengths of integral bridges increase and decrease, pushing the abutment against the approach fill and pulling it away. As a result the bridge superstructure, the abutment, the approach f...

  6. Influence of dynamic soil-pile raft-structure interaction: an experimental approach

    Science.gov (United States)

    Saha, Rajib; Haldar, Sumanta; Dutta, Sekhar Chandra

    2015-12-01

    Traditionally seismic design of structures supported on piled raft foundation is performed by considering fixed base conditions, while the pile head is also considered to be fixed for the design of the pile foundation. Major drawback of this assumption is that it cannot capture soil-foundation-structure interaction due to flexibility of soil or the inertial interaction involving heavy foundation masses. Previous studies on this subject addressed mainly the intricacy in modelling of dynamic soil structure interaction (DSSI) but not the implication of such interaction on the distribution of forces at various elements of the pile foundation and supported structure. A recent numerical study by the authors showed significant change in response at different elements of the piled raft supported structure when DSSI effects are considered. The present study is a limited attempt in this direction, and it examines such observations through shake table tests. The effect of DSSI is examined by comparing dynamic responses from fixed base scaled down model structures and the overall systems. This study indicates the possibility of significant underestimation in design forces for both the column and pile if designed under fixed base assumption. Such underestimation in the design forces may have serious implication in the design of a foundation or structural element.

  7. Investigating Potential Toxicity of Leachate from Wood Chip Piles Generated by Roadside Biomass Operations

    OpenAIRE

    John Rex; Stephane Dubé; Phillip Krauskopf; Shannon Berch

    2016-01-01

    Roadside processing of wood biomass leaves chip piles of varying size depending upon whether they were created for temporary storage, spillage, or equipment maintenance. Wood chips left in these piles can generate leachate that contaminates streams when processing sites are connected to waterways. Leachate toxicity and chemistry were assessed for pure aspen (Populus tremuloides Michx.), lodgepole pine (Pinus contorta Dougl.), hybrid white spruce (Picea engelmannii x glauca Parry), and black s...

  8. FORECASTING PILE SETTLEMENT ON CLAYSTONE USING NUMERICAL AND ANALYTICAL METHODS

    Directory of Open Access Journals (Sweden)

    Ponomarev Andrey Budimirovich

    2016-06-01

    Full Text Available In the article the problem of designing pile foundations on claystones is reviewed. The purpose of this paper is comparative analysis of the analytical and numerical methods for forecasting the settlement of piles on claystones. The following tasks were solved during the study: 1 The existing researches of pile settlement are analyzed; 2 The characteristics of experimental studies and the parameters for numerical modeling are presented, methods of field research of single piles’ operation are described; 3 Calculation of single pile settlement is performed using numerical methods in the software package Plaxis 2D and analytical method according to the requirements SP 24.13330.2011; 4 Experimental data is compared with the results of analytical and numerical calculations; 5 Basing on these results recommendations for forecasting pile settlement on claystone are presented. Much attention is paid to the calculation of pile settlement considering the impacted areas in ground space beside pile and the comparison with the results of field experiments. Basing on the obtained results, for the prediction of settlement of single pile on claystone the authors recommend using the analytical method considered in SP 24.13330.2011 with account for the impacted areas in ground space beside driven pile. In the case of forecasting the settlement of single pile on claystone by numerical methods in Plaxis 2D the authors recommend using the Hardening Soil model considering the impacted areas in ground space beside the driven pile. The analyses of the results and calculations are presented for examination and verification; therefore it is necessary to continue the research work of deep foundation at another experimental sites to improve the reliability of the calculation of pile foundation settlement. The work is of great interest for geotechnical engineers engaged in research, design and construction of pile foundations.

  9. Experimental Comparison of Statically and Cyclically Loaded Non-Slender Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo

    The monopile foundation concept is often employed as foundation for offshore wind energy converters. Typically, monopiles are hollow piles made of steel with outer diameters, D, in the range of four to six meters and length to diameter ratios, L/D, around five. Hence, the piles exhibit a rather r...... with strain gauges have been used for the test series. The outer pile diameter has been varied between 40 and 100 mm, the length to diameter ration is between three and six and the overburden pressure is between 0 and 100 kPa....... the effective stresses in the soil will be low and vary linearly with depth. As a consequence of this the soil parameters will vary greatly with depth and the determination of soil parameters is subject to great uncertainties. To overcome these uncertainties an overburden pressure, P0, has been applied...... and hence the effective stresses in the soil have been increased homogeneously. The tests have been conducted in a pressure tank at Aalborg University. A total of 29 quasi-static tests and 14 cyclic tests have been conducted on laterally loaded piles situated in sand. Aluminium pipe piles instrumented...

  10. Big Pile or Small Pile?

    Science.gov (United States)

    Branca, Mario; Quidacciolu, Rossana G.; Soletta, Isabella

    2013-01-01

    The construction of a voltaic pile (battery) is a simple laboratory activity that commemorates the invention of this important device and is of great help in teaching physics. The voltaic pile is often seen as a scientific toy, with the "pile" being constructed from fruit. These toys use some strips of copper and zinc inserted in a piece…

  11. De-regulated electric power markets and operating nuclear power plants: the case of British energy

    International Nuclear Information System (INIS)

    One issue addressed in almost all electric power restructuring/de-regulation plans in both the United States (US) and the United Kingdom (UK) was the recovery of operating nuclear power plant's spent fuel disposal costs and the expenditures to decommission the units when they are retired. Prior to restructuring, in theory at least, in both countries, electricity consumers were paying for the back end costs from operating nuclear power plants. Moreover, in virtually all cases in the US, states included special provisions to insure that consumers would continue to do so after power markets were de-regulated. When power markets in the UK were initially restructured/de-regulated and nuclear power privatized, the shareholders of British Energy (BE) were initially responsible for these costs. However, after electricity prices fell and BE collapsed, the British government shifted many of the costs to future taxpayers, as much as a century forward. If this was not done, the book value of BE's equity would have been about -3.5 billion pounds. That is, BE's liabilities would have been about -3.5 billion pounds greater than their assets. It is difficult to see how BE could remain viable under such circumstances

  12. Investigating Potential Toxicity of Leachate from Wood Chip Piles Generated by Roadside Biomass Operations

    Directory of Open Access Journals (Sweden)

    John Rex

    2016-02-01

    Full Text Available Roadside processing of wood biomass leaves chip piles of varying size depending upon whether they were created for temporary storage, spillage, or equipment maintenance. Wood chips left in these piles can generate leachate that contaminates streams when processing sites are connected to waterways. Leachate toxicity and chemistry were assessed for pure aspen (Populus tremuloides Michx., lodgepole pine (Pinus contorta Dougl., hybrid white spruce (Picea engelmannii x glauca Parry, and black spruce (Picea mariana (Mill. Britton as well as from two wood chipping sites using mixes of lodgepole pine and hybrid or black spruce. Leachate was generated using rainfall simulation, a static 28-day laboratory assay, and a field-based exposure. Leachate generated by these exposures was analyzed for organic matter content, phenols, ammonia, pH, and toxicity. Findings indicate that all wood chip types produced a toxic leachate despite differences in their chemistry. The consistent toxicity response highlights the need for runoff management that will disconnect processing sites from aquatic environments.

  13. Experimental and Theoretical Research of Deformation of Vertically Loaded Displacement Piles in Sand Soil

    Directory of Open Access Journals (Sweden)

    Tautvydas Statkus

    2014-12-01

    Full Text Available The displacement piles are one of the oldest type of foundation not just in Lithuania, but also all over the world. Stiff, glacial origin sands lay not far from the ground surface in Lithuania as opposed to the rest of the Western Europe, therefore this kind of foundation is carried out into practice very often in our country. For geotechnical engineers it is very hard to decide which method should be applied, when there is no local experience. Five approaches are discussed on this paper and the results of three single piles’ tests are compared. The full scale single piles’ tests were carried out at the artificial bearing stratum pit. Piles’ diameter was 330 mm. The ratio of the piles’ depth and diameter were 3.3, 4.4 and 4.8. In conclusion of this paper the recommendations are given, which should be applied in different cases using mentioned above methods.

  14. Piled Embankment Design Comparison

    Directory of Open Access Journals (Sweden)

    Drusa Marián

    2015-05-01

    Full Text Available There are currently several national standards or regulations for the design of the piled embankment, providing suitable solutions for foundation of transport structure on soft, high compressible subsoil, [1]. The most widely used and the best-known standard is British Standard BS8006 [2], which was confronted with another analytical design methodologies (Ebgeo, CUR. Today’s popularity and versatility of FEM numerical models brings many advantages, which analytical methods cannot achieved, but must be verified by proposed scaled physical model, which was currently being developed by Department of Geotechnics, University of Žilina.

  15. Piled Embankment Design Comparison

    Science.gov (United States)

    Drusa, Marián; Kais, Ladislav; Vlček, Jozef; Mečár, Martin

    2015-05-01

    There are currently several national standards or regulations for the design of the piled embankment, providing suitable solutions for foundation of transport structure on soft, high compressible subsoil, [1]. The most widely used and the best-known standard is British Standard BS8006 [2], which was confronted with another analytical design methodologies (Ebgeo, CUR). Today's popularity and versatility of FEM numerical models brings many advantages, which analytical methods cannot achieved, but must be verified by proposed scaled physical model, which was currently being developed by Department of Geotechnics, University of Žilina.

  16. Operating systems for experimental physics

    International Nuclear Information System (INIS)

    Modern high energy physics experiments are very dependent on the use of computers and present a fairly well defined list of technical demands on them. It is therefore possible to look at the construction of a computer operating system and to see how the design choices should be made in order to make the systems as useful as possible to physics experiments or, more practically, to look at existing operating systems to see which can most easily be used to do the jobs of rapid data acquisition and checking. In these notes, operating systems are looked at from the point of view of the informed user. Emphasis is placed on systems which are intended for single processor microcomputers of the type frequently used for data acquisition applications. The principles described are, of course, equally valid for other kinds of system. (Auth.)

  17. Impacts of the operation of existing hydroelectric developments on fishery resources in British Columbia

    International Nuclear Information System (INIS)

    The main features of 46 hydroelectric dams and diversions in British Columbia are reviewed, and available information on the inland sport fish resources within and below the impoundments are summarized. The projects are collectively responsible for ca 95% of the electrical power used in the province. The characteristics detailed include water license and operational constraints, electrical generation, enhancement facilities, operational regime, physical and chemical environment, downstream system, sportfish populations, and recreational fishery. All the hydroelectric impoundments reviewed, with the possible exceptions of some small headponds, support sport fish populations. Recreational angling quality is considered good for about one quarter of impoundments for which information is available. Low population density is the dominant reason for poor angling quality. Drawdowns exceeding 10 m annually and/or low water retention times are significant impediments to sport fish stock densities. Recommended measures to improve sport fishery resources in and below hydroelectric impoundments include evaluation of the efficiency of ongoing compensation programs, improvement to impact assessment procedures to ensure adequate documentation of pre- and post-impoundment conditions, and enhancement of several systems through stock or nutritional supplementation. 161 refs., 95 figs., 9 tabs

  18. Compressive Experimental Study of Micro Piles by Concreting Method%灌注细石混凝土微型桩基础下压试验研究

    Institute of Scientific and Technical Information of China (English)

    苏荣臻; 邱书清; 鲁先龙

    2012-01-01

    通过现场真型试验,对灌注细石混凝土成桩微型桩基础抗压承载机理及其抗压承载力计算方法进行了研究.试验表明:本次试验条件下,微型桩单桩可看成纯摩擦桩进行抗压承载力计算;微型桩群桩在极限下压荷载作用下,承台底部土体承担荷载比例仅为4.8%,在进行微型桩群桩抗压极限承载力计算时可不考虑承台底土的承载作用;由于承台对下压荷载的重分配,在下压荷载作用下,角桩承力最大,边桩次之,中桩最小;本次试验条件下,微型桩抗压群桩效应系数可取0.8进行计算.%In (his paper, field tests were done to study the compressive bearing mechanism and compressive design method of micropiles. Study shows: in this experimental condition, single micropile can be regarded as friction pile to calculate the compressive bearing capacity; under the ultimate load, the bearing ratio of the soil under the cap of micropile group is only 4. 8% , so calculating the compressive bearing capacity of micropile group cannot take into account the role of subsoil bearing; under compressive load, the bearing load of the angle pile is maximum, the side pile is the second, and the middle pile is minimum; in this experimental condition, the compressive pile group effect coefficient is 0. 8.

  19. Grouted jetted precast concrete sheet piles: Method, experiments, and applications

    OpenAIRE

    Xu, GH; Yue, ZQ; Liu, DF; He, FR

    2006-01-01

    This paper introduces an innovative technology - grouted jetted precast concrete piling - that increases the efficiency of piling operations in coastal regions. The technology includes the following steps: (i) casting concrete piles factory-designed especially for jetting and grouting; (ii) jetting to drive the concrete piles with a crane on a floating ship or platform into soil; and (iii) grouting to enhance the sheet pile connections and to increase the pile bearing capacity. This technolog...

  20. The auxiliary pile driving jet simulation and experimental study%辅助沉桩水射流模拟分析及实验研究

    Institute of Scientific and Technical Information of China (English)

    蒲高军

    2012-01-01

    针对大直径、超长钢管桩建设中存在的问题,提出利用水射流技术辅助开展沉桩,理论分析了不同喷嘴的水力参数,并数值模拟喷嘴的流场特性及各喷嘴对岩土体内部应力作用分析,最后选用等变速型喷嘴制作射流喷头,开展射流辅助沉桩实验,结果显示随着射流强度的提高,沉桩需要的锤击次数越小,同时也反映要根据实际沉桩状况及时进行射流排量的调节。%For the problems in the construction of large diameter or long steel pipe piles, water jet technology was in support of the pile driving in the paper. The article analyzed the different nozzle hydraulic parameters in theoretical aspects, and then analyzed flow field of the nozzle and the internal stress of the rock mass with numerical simulation. At last, shift type nozzle to produce jet nozzle, to carry out the experimental jet assisted pile driving. The results showed the jet strength increased, the smaller number of times would the pile driving hammering display. Also it reflected that the jet emission should be regulated in a timely manner according to the actual pile driving conditions.

  1. Experimental Investigation and Finite Element Analysis of Prestressed High Strength Concrete Pile-Pile Cap Connections%PHC管桩与承台连接节点试验研究与有限元分析

    Institute of Scientific and Technical Information of China (English)

    王铁成; 杨志坚; 赵海龙; 王文进

    2015-01-01

    Based on the results of four prestressed high strength concrete(PHC)pile-pile cap connections under cyclic loading,the failure patterns and the mode of the specimens are described. The strain of pile,anchor bars and carbon fiber-reinforced polymer(CFRP),hysteretic curve,bearing capacity and displacement ductility of connections are analyzed. The test results show that the cap of specimens appeared to be a squeezing failure. The anchor bars lost con-straint,and formed a hinge joint that resulted in the connection rotation being unrestricted and the rotation capacity of connection being increased. PHC pile reinforced by steel fiber and non-prestressed steel bars can improve the dis-placement ductility of connections. The connections should be designed with enough rotating capacity,which ensures that the cap will not be damaged by squeezing or prying due to the rotating of the pile end. The finite element software OpenSees was used to simulate the nonlinear behavior of pile-cap connections under cyclic loading. Comparison be-tween analytical and experimental results shows that the proposed modeling technique is capable of accurately describ-ing the cyclic behavior of the connections.%对4个预应力高强混凝土(PHC)管桩与承台连接节点进行了低周往复荷载试验,描述了试件的破坏过程和形态,分析了桩身混凝土、锚固钢筋以及碳纤维约束预应力混凝土管桩(CFRP)的应变,对构件的滞回曲线、承载力和位移延性等进行了研究。试验结果表明,在弯矩作用下,节点区域混凝土被压碎,节点区锚固钢筋约束减弱,形成铰接点,节点转动能力变大;在桩身混凝土中掺入钢纤维以及配置非预应力筋可以提高节点的位移延性;在进行节点设计时,应保证承台不会由于桩端转动时产生的挤压力或撬力作用过早地发生破坏。采用有限元分析软件OpenSees对节点在往复荷载作用下的受力性能进行了模拟分

  2. Experimental studies on local scour of offshore wind turbine pile%海上风电桩基局部冲刷试验研究

    Institute of Scientific and Technical Information of China (English)

    祁一鸣; 陆培东; 曾成杰; 陈可锋

    2015-01-01

    The foundation of a wind turbine pile is the load of the wind turbine itself and the lateral pressure of the blade rotation, and the stability of a pile foundation is very important. The offshore wind turbine pile is not only influenced by the tidal current and wave interaction, but also the scale of the pile foundation, which is usually between the pier and the pile foundation, and its local scour has some particularity. By establishing a normal model of 1∶60, the local scour of the offshore wind turbine pile foundation under the action of wave, tidal current and wave current is studied. The research results show that:①the tidal current is the dominant factor in controlling the local scour of the pile foundation in the sea area;②under the action of the alternating flow, the shape of the scour hole is oval, and the maximum scour depth is about 0. 8 of the steady flow;③under the wave⁃current interaction, due to the role in the front of the pile wave oscillating flow, sediment is easier to move than the current action, the local scour is significantly enhanced, and the maximum scour depth is 2. 0 and 1. 7 times under the action of tidal current and constant flow;④the calculated values given by the Han Hai⁃qian formula are in good agreement with the experimental values of the scour depth of the pile foundation under the influence of the coefficient 0. 75. According to the test results, it is suggested that the riprap protection of local scour around the pile foundation pit should be done in order to ensure the security and stability of the offshore wind turbine.%风电桩基既承担风机自身荷载,又受到叶片转动的侧向压力,桩基稳定性至关重要。海上风电桩基不仅受潮汐双向水流和波浪共同作用的影响,而且桩基尺度介于通常的桥墩和码头桩基之间,局部冲刷具有一定特殊性。通过建立1∶60的正态模型,研究了洋口海域海上风电桩基在波浪、潮流及波流共同

  3. Effects of fuel properties on the natural downward smoldering of piled biomass powder: Experimental investigation

    International Nuclear Information System (INIS)

    To validate the modeling of one-dimensional biomass smoldering and combustion, the effects of fuel type, moisture content and particle size on the natural downward smoldering of biomass powder have been investigated experimentally. A cylindrical reactor (inner size Φ26 cm × 22 cm) was constructed, and corn stalk, pine trunk, pyrolysis char and activated char from corn stalk were prepared as powders. The smoldering characteristics were examined for each of the four materials and for different moisture contents and particle sizes. The results revealed the following: 1) The maximum temperature in the fuel bed is only slightly affected by the fuel type and particle size. It increases gradually for original biomass and decreases slowly for chars with the development of the process. 2) The propagation velocity of the char oxidation front is significantly affected by the carbon density and ash content and nearly unaffected by moisture content and particle size. 3) The propagation velocity of the drying front is significantly affected by the moisture content, decreasing from over 10 times the propagation velocity of char oxidation front to about 3 times as the moisture content increased from 3 to 21%. - Highlights: • Natural downward smoldering of four materials, different moisture contents, and different particle sizes were investigated. • Propagation velocity of the char oxidation front differs significantly from that of the drying front. • Carbon density and ash content of fuel significantly affect propagation velocity of the char oxidation front

  4. Qualification of an out-of-pile Thermohydraulic test Bench (BETHY) developed to calibrate calorimetric cells under specific JHR experimental conditions

    International Nuclear Information System (INIS)

    Online in-pile measurement methods are crucial during irradiations in material testing reactors to better understand the behavior of materials under accelerated ageing conditions and of nuclear fuels under high irradiation levels. Thus, the construction of a new Material Testing Reactor such as the Jules Horowitz Reactor (JHR) leads to new research and development programs devoted to innovative instrumentation and measurement methods. The presented works are performed in the framework of the IN-CORE program, 'Instrumentation for Nuclear radiations and Calorimetry Online in Reactor', between CEA and Aix-Marseille University. The program aim is to develop experimental devices and test bench to quantify more precisely the nuclear heating parameter in the JHR experimental channels. This in-pile parameter is usually measured by means of calorimeter or gamma thermometer. This paper focuses on a new out-of-pile test bench called BETHY. This bench was developed to study the response of a differential calorimeter during its preliminary calibration step according to specific thermal and hydraulic conditions occurring inside one type of JHR core channel. The first section of this paper is dedicated to a detailed description of the bench. The second part presents the study of the thermal characteristics established in the bench for two main thermal running modes. The last one concerns the calibration curve of the reference cell of the differential calorimeter in the case of homogenous temperature. (authors)

  5. 30 CFR 77.215-4 - Refuse piles; abandonment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; abandonment. 77.215-4 Section 77... MINES Surface Installations § 77.215-4 Refuse piles; abandonment. When a refuse pile is to be abandoned... refuse pile shall be abandoned in accordance with a plan submitted by the operator and approved by...

  6. Parametric study on the effects of pile inclination angle on the response of batter piles in offshore jacket platforms

    Science.gov (United States)

    Aminfar, Ali; Ahmadi, Hamid; Aminfar, Mohammad Hossein

    2016-06-01

    Offshore jacket-type platforms are attached to the seabed by long batter piles. In this paper, results from a finite element analysis, verified against experimental data, are used to study the effect of the pile's inclination angle, and its interaction with the geometrical properties of the pile and the geotechnical characteristics of the surrounding soil on the behavior of the inclined piles supporting the jacket platforms. Results show that the inclination angle is one of the main parameters affecting the behavior of an offshore pile. We investigated the effect of the inclination angle on the maximum von Mises stress, maximum von Mises elastic strain, maximum displacement vector sum, maximum displacement in the horizontal direction, and maximum displacement in the vertical direction. The pile seems to have an operationally optimal degree of inclination of approximately 5°. By exceeding this value, the instability in the surrounding soil under applied loads grows extensively in all the geotechnical properties considered. Cohesive soils tend to display poorer results compared to grained soils.

  7. Research on method of pressure grouting piling of driven tube

    Institute of Scientific and Technical Information of China (English)

    Dianqi PAN; Zupei ZHANG; Diancai PAN; Yong CHEN; Maosen TAN

    2006-01-01

    The pressure grouting pile of driven tube can improve the load bearing capacity of the single pile from the mechanism of pressure grouting pile of driven tube. On the basis of analyzing the mechanism, the authors designed the machines and tools of pressure grouting, determined the operating manufacture and technology parameter on the pressure grouting secondly. The result shows that the pressure grouting pile of driven tube not only changes the pile type but also reduce the length of the pile and its engineering cost, it enhances the load bearing capacity of single pile an the same time.

  8. Experiments of Multi-element Composite Foundation with Steel Pipe Pile and Gravel Pile

    Institute of Scientific and Technical Information of China (English)

    WANG Xian-zhi; ZHENG Jun-jie

    2008-01-01

    A set of self-developed apparatus for foundation physical model were utilized to conduct model tests of the multi-element composite foundation with a steel pipe pile and several gravel piles. Some load-bearing characteristics of the multi-element composite foundation, including the curves of foundation settlement, stresses of piles, pile-soil stress ratio, and load-sharing ratio of piles and soil, were obtained to study its working performances in silty sand soil. The experimental results revealed that the multi-element composite foundation with steel pipe pile and gravel pile contributed more than the gravel pile composite foundation in improving the bearing capacity of the silty fine sand.

  9. Decommissioning of Windscale pile 1

    International Nuclear Information System (INIS)

    The Windscale Piles were constructed in the late 1940's primarily for the production of plutonium in support of the British atomic weapons programme. In 1957 Pile 1 suffered a fire during the routine release of stored Wigner energy by nuclear heating. Following the fire as much material as possible was recovered, an inventory and status report prepared and the pile sealed and placed under surveillance and maintenance, the only practicable option at the time. Over the last decade in addition to general improvements in routine monitoring equipment there has been extensive investigative work carried out to better understand the damage caused by the fire and assess the options for further action. These studies concluded that the preferred option was for the Pile core to be removed, treated and packaged for intermediate storage prior to final disposal. The paper will describe the core investigations, the assessed conditions, and the options considered. It will also describe the tendering process to allow contractors to propose solutions against a cardinal point specification, the outline of the preferred solution and the progress of the work to date. (author)

  10. 高压旋喷桩加固后桩基水平静载原位试验研究%In Situ Experimental Study on Horizontal Load of Pile Foundation after Reinforcement by High -pressure Jet Grouting Piles

    Institute of Scientific and Technical Information of China (English)

    翁雅谷; 王欢; 何奔; 陈国兴

    2015-01-01

    Properties of soil around piles at shallow level show great influences on horizontal carrying capacity of pile bodies,and reinforcement of soil around piles to improve horizontal carrying capacity of pile bodies is an economical and effective way,but at present studies on it are very few at home.This paper studies and analyzes horizontal static loading properties of pouring piles in soft soil after reinforcement by high -pressure jet pouring piles via site full -scale horizontal loading test to provide preconditions and essential bases for further dynamic calculation.The test results show that after soil mass which extension is 5 and 7.5 times the D (D is diameter of pouring piles)is reinforced by high -pressure jet pouring piles,the horizontal carrying capacity of pouring piles is increased by 2 /3 and 1 time respectively,and the bending moment of pile bodies decreases remarkably so as to anti -crack performance of jet pouring piles greatly and guarantee that sectional concrete of pile bodies does not crack at large horizontal action force.%浅层桩周土的性能对桩体水平承载力有很大影响,通过加固桩周土来提高桩体水平承载力是一种经济有效的手段,但目前国内其研究甚少。通过现场全尺度水平加载试验来研究、分析高压旋喷桩加固后灌注桩在软土中的水平静力加载性能,为进一步动力计算提供前提条件和基本依据。试验结果表明:将延深度5倍和7.5倍 D(D 为灌注桩桩径)范围内的土体进行高压旋喷桩加固后,灌注桩水平承载力分别提高了2/3和1倍,且其桩身弯矩显著下降,从而大大提高了旋喷桩的抗开裂性能,保证桩体能在较大水平作用力下截面混凝土不发生开裂。

  11. Global and local scour at pile groups

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Bundgaard, Klavs; Fredsøe, Jørgen

    2005-01-01

    This paper presents the results of an experimental investigation on scour around pile groups with different configurations exposed to steady current. Two kinds of tests were carried out: rigid-bed tests and actual scour tests. In these, the mean and turbulence properties of the flow were measured...... across the pile groups. The pile-group configurations were such that the global scour was distinguished from the local scour. The results show that the global scour can be quite substantial....

  12. Global and local scour at pile groups

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Bundgaard, Klavs; Fredsøe, Jørgen

    2005-01-01

    This paper presents the results of an experimental investigation on scour around pile groups with different configurations exposed to steady current. Two kinds of tests were carried out: (1) Rigid-bed tests, and (2) Actual scour tests. In the former tests, the mean and turbulence properties...... of the flow were measured across the pile groups. The pile group configurations were such that the global scour was distinguished from the local scour. The results show that the global scour can be quite substantial....

  13. Safety precautions in atomic pile control (1962)

    International Nuclear Information System (INIS)

    We have been led to study the problem of safety in atomic pile control as a result of our participation on the one hand in the planning of C.E.A. atomic piles, and on the other hand in the pile safety sub omission considering atomic pile safety of operational or planned C.E.A. piles. We have thus had to consider the wishes occurring in piles during their operation and also their behaviour in the dynamic state The present work deals mainly with the importance of intrinsic safety devices, with the influence of reactivity variations on the power fluctuations during accidental operation, and with the development of robust and reliable safety appliances. The starting p accident has been especially studied both for low-flux piles where a compromise is necessary between the response time of the safety appliances and the statistical fluctuations and for high lux piles where xenon poisoning has an effect on the lower limit of the velocity of reactivity liberation. The desirability has been stressed of automation as a safety factor in atomic pile control. The details required for an understanding of the diagrams of the apparatus are given. (author)

  14. Soil stress field around driven piles

    OpenAIRE

    Allard, Marie-Agnes

    1989-01-01

    The description, equipment, and results of a series of pile-driving experiments conducted in a centrifuge using a model pile driven in dry sand are presented. The work was conceived on the basis of the modelling of a soil-structure system under an artificially generated gravitational field, and motivated by the need for experimental data for a better understanding of the complex phenomena involved in the pile-soil interaction during driving. The behavior of the pile itself has been the fo...

  15. Fabrication of the 4. set of fuel elements for the experimental pile EL2; Fabrication du 4. jeu de barreaux de la pile d'essai EL2

    Energy Technology Data Exchange (ETDEWEB)

    Ringot, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The reactor EL2 is the second atomic reactor built in France. It is a laboratory reactor using heavy water and natural uranium. Its cooling circuit operates with compressed CO{sub 2} gas at 8 kg/cm{sup 2} pressure. The subject of this lecture is the manufacturing of the fourth set of rods. The principle of uranium-can connection is exposed: that is the principle of a pre-pressed bound can. The EL2 reactor has been a prototype with respect to this aspect of the question, and a prototype which has been quite satisfactory. The main steps of the fabrication are exposed: the {gamma} phase extension of uranium, the machining, the three canning (die canning, hydraulic canning, compressed air treatment), the automatic argon arc welding of cups and the different manufacturing controls. (author) [French] Le reacteur EL2 est le deuxieme reacteur construit en France. C'est un reacteur de recherches qui utilise de l'eau lourde et de l'uranium naturel. Il est refroidi par du gaz carbonique sous 8 kg/cm{sup 2} de pression. On etudie dans cet expose la fabrication du quatrieme jeu d'elements combustibles. Le principe de la liaison uranium-gaine est expose: c'est celui d'une gaine precontrainte. La pile EL2 a constitue un prototype a ce point de vue, prototype qui a donne entiere satisfaction. Les principales etapes de la fabrication sont ensuite expliquees: le filage {gamma} de l'uranium, l'usinage des barreaux, les trois operations de gainages (gainage par filiere, gainage hydraulique, gainage a chaud), la soudure automatique des bouchons a l'argon-arc et les differents controles de fabrication. (auteur)

  16. EXPERIMENTAL STUDY OF SEISMIC PERFORMANCE OF PHC PIPE PILE CONSIDERING SOIL-PILE-STRUCTURE INTERACTION%考虑土-桩-结构相互作用的PHC管桩抗震性能试验研究

    Institute of Scientific and Technical Information of China (English)

    李曰辰; 邢克勇; 刘浩; 陈明祥

    2013-01-01

    A shaking table model test of the earthquake performance of PHC pipe pile under seismic excitations considering soil-pile-structure interaction effect is presented.Features of the shaking table test include a variety of pile models,i.e.single pile,three piles,and six piles,and a shear soil box consisting of clay,silt,and sand layers.The various developed soil-pile-structure systems are then subjected to three sets of seismic ground motions.Each set of the earthquake events is composed of five input excitation scenarios with varying intensities.The evaluation results show that along with earthquake continues,each model system natural frequency decreases and damping increases.The earthquake intensity has a significant effect on the soil-pile-structure system.Specifically,the soil-pile-structure interaction and soil nonlinearity effects are observed to go up as the intensity increases.The nonlinearity effects of systems with fewer piles are stronger than those with more piles.Moreover,the number and arrangement pattern of the piles as well as the configuration of the upper structure can exert substantial impact on the strain and bending moment responses.It is shown that compared to the single-pile model,the maximum tensile strains of the three-pile model and six-pile model drop by 23 percent and 66 percent respectively,whereas the maximum bending moments decrease by 29 percent and 70 percent respectively.On the other hand,the soil-pile interface pressure reduces by 22 percent and 32 percent respectively.It is also found that the damage behaviors for systems with more piles are less severe than those with fewer piles.The results of this preliminary investigation further indicate the feasibility of exploiting PHC piles in high seismicity regions.Nonetheless,it is also suggested that more research efforts are required for extensive application of PHC piles in such areas.%通过振动台模型试验,在考虑土-桩-结构相互作用的条件下研究PHC管桩的抗震

  17. Hydrodynamic Behavior of Curtainwall-Pile Breakwaters

    Institute of Scientific and Technical Information of China (English)

    O.Nejadkazem; A.R.M.Gharabaghi

    2012-01-01

    A numerical model is developed that can predict the interaction of regular waves normally incident upon a curtainwall-pile breakwater; the upper part of which is a vertical wall and the lower part consists of an array of vertical piles.The numerical model is based on an eigenfunetion expansion method,and utilizes a boundary condition nearby the vertical piles that accounts for wave energy dissipation.Numerical solution comprises a finite number of terms,which is a superposition of propagating waves and a series of evanescent waves.The modeling is validated by comparison with previous experimental studies and overall agreement between measurement and calculation is fairly good.The numerical results are related to reflection,transmission,and dissipation coefficient; wave run-up,wave force,and wave overturning moment are also presented.Effect of porosity,relative draft,and relative water depth are discussed; the choice of suitable range of them is described.The relative draft is more effective for shallow water waves.Model shows decrease in relative draft and leads to reduction of relative wave force,overturning moment,and nunup.It is shown that curtainwallpile breakwaters can operate both effectively and efficiently in the range of relative draft between 0.15 and 0.75.The range 0.5 to 0.2 is also recommended for porosity.

  18. Experimental study concerning lift bearing value of wide bottom and caison type pile foundation for transmission pylon

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, Kazuo; Tanino, Kengo; Sugiyama, Futami

    1988-07-30

    The transmission route becomes mountain area because many power sources become distant, so that the foundations must be mainly made by manpower. Therefore, the caison type pile foundation is used in many cases and further the scale becomes larger. The wide bottom foundation, where the base bottom is enlarged, is applied to construct economically. It is known that the lift bearing value is increased by enlarging the width but it is necessary to confirm whether the existing calculation technique can be applied or not, so that large field tests and model experimenta in a centrifugal force field were conducted. The lift bearing value is increased with the increase of penetration but the fracture type changes from the logarithmic spiral to the withdrawal type and when the surface inclines, the foundation inclines to valley side even if the lift load is vertical. Moreover, if the foundation width is smaller, the ground over the enlarged width is compressed, resulting fracture of the withdrawal type but if the width is too large, the fracture type changes to the logarithmic spiral type and the bearing value becomes larger. It is necessary to select ground which is uncompressible or has positive dilatancy. (30 figs, 10 tabs, 3 refs)

  19. Safety precautions in atomic pile control (1962); Securite dans le controle des piles atomiques (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Furet, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    We have been led to study the problem of safety in atomic pile control as a result of our participation on the one hand in the planning of C.E.A. atomic piles, and on the other hand in the pile safety sub omission considering atomic pile safety of operational or planned C.E.A. piles. We have thus had to consider the wishes occurring in piles during their operation and also their behaviour in the dynamic state The present work deals mainly with the importance of intrinsic safety devices, with the influence of reactivity variations on the power fluctuations during accidental operation, and with the development of robust and reliable safety appliances. The starting p accident has been especially studied both for low-flux piles where a compromise is necessary between the response time of the safety appliances and the statistical fluctuations and for high lux piles where xenon poisoning has an effect on the lower limit of the velocity of reactivity liberation. The desirability has been stressed of automation as a safety factor in atomic pile control. The details required for an understanding of the diagrams of the apparatus are given. (author) [French] Nous avons aborde le probleme de la securite dans le controle des piles atomiques a la suite de notre participation d'une part aux avant rojets de piles atomiques du CE.A. et d'autre part a l'examen au sein de la sous ommission de surete des piles, de la securite des piles du CE.A. en fonctionnement ou en projet. Nous avons ete amenes a nous interesser alors aux risques encourus par les piles pendant leur fonctionnement et par la meme a leur comportement en regime dynamique. Ce travail traite principalement de l'importance des securites intrinseques, de l'influence des variations de reactivite sur les evolutions de puissance en regime d'accident et du developpement d'appareillages de securite robustes et de fonctionnement tres sur. L'accident de demarrage a ete particulierement

  20. 双速度法检测基桩完整性试验研究%Experimental Study on Integrity Inspection of Foundation Pile by Double Speed Test

    Institute of Scientific and Technical Information of China (English)

    唐勇

    2012-01-01

    The low strain test method of foundation pile is applied to check the integrity of bridge foundation pile, driven pile and anti-sliding pile extensively, but the check is difficult to be carried out in case of restrained pile top. Then the double speed test could be used, which could be also applied in case of the foundation pile of existing building, the foundation pile being connected to upper structure, and the pile length unknown. Through single and double speed tests for 16 model piles with and without cap, 766 groups of data are obtained for analysis. As a result, it is proved that the method could be absolutely applied in engineering foundation pile inspection and has realistic meaning about the related integrity check.%基桩低应变测试法被广泛应用于测试桥梁基桩、打入桩和抗滑桩等的完整性。但是,桩顶非自由的情况测试就非常困难。此时可采用双速度法检测,此方法也适于测试已有建筑物下的基桩及基桩与上部结构相连且桩长未知的情况。通过16根有承台和无承台模型桩的单速度和双速度测试,取得766组数据进行分析,得出此方法完全可以应用于工程基桩检测中,对基桩完整性检测具有现实意义。

  1. 12 April 2013 - The British Royal Academy of Engineering visiting the LHC superconducting magnet test hall with R. Veness and the ATLAS experimental cavern with Collaboration Spokesperson D. Charlton.

    CERN Multimedia

    Jean-Claude Gadmer

    2013-01-01

    12 April 2013 - The British Royal Academy of Engineering visiting the LHC superconducting magnet test hall with R. Veness and the ATLAS experimental cavern with Collaboration Spokesperson D. Charlton.

  2. Operational aspects of experimental accelerator physics

    Energy Technology Data Exchange (ETDEWEB)

    Decker, G.A.

    1995-07-01

    During the normal course of high energy storage ring operations, it is customary for blocks of time to be allotted to something called ``machine studies,`` or more simply, just ``studies.`` It is during these periods of time that observations and measurement of accelerator behavior are actually performed. Almost invariably these studies are performed in support of normal machine operations. The machine physicist is either attempting to improve machine performance, or more often trying to recover previously attained ``good`` operation, for example after an extended machine down period. For the latter activity, a good portion of machine studies time is usually devoted to ``beam tuning`` activities: those standard measurements and adjustments required to recover good operations. Before continuing, please note that this paper is not intended to be comprehensive. It is intended solely to reflect one accelerator physicist`s impressions as to what goes on in an accelerator control room. Many topics are discussed, some in more detail than others, and it is not the intention that the techniques described herein be applied verbatim to any existing accelerator. It is hoped,, however, that by reading through the various sections, scientists, including accelerator physicists, engineers, and accelerator beam users, will come to appreciate the types of operations that are required to make an accelerator work.

  3. Hazardous gases and oxygen depletion in a wet paddy pile: an experimental study in a simulating underground rice mill pit, Thailand.

    Science.gov (United States)

    Yenjai, Pornthip; Chaiear, Naesinee; Charerntanyarak, Lertchai; Boonmee, Mallika

    2012-01-01

    During the rice harvesting season in Thailand, large amounts of fresh paddy are sent to rice mills immediately after harvesting due to a lack of proper farm storage space. At certain levels of moisture content, rice grains may generate hazardous gases, which can replace oxygen (O(2)) in the confined spaces of underground rice mill pits. This phenomenon has been observed in a fatal accident in Thailand. Our study aimed to investigate the type of gases and their air concentrations emitted from the paddy piles at different levels of moisture content and duration of piling time. Four levels of moisture content in the paddy piles were investigated, including dry paddy group (concrete pits 80 × 80 cm wide by 60 cm high. Gases emitted were measured with an infrared spectrophotometer and a multi-gas detector every 12 h for 5 days throughout the experiment. The results revealed high levels of carbon dioxide (CO(2)) (range 5,864-8,419 ppm) in all wet paddy groups, which gradually increased over time. The concentration of carbon monoxide (CO), methane (CH(4)), nitromethane (CH(3)NO(2)) and nitrous oxide (N(2)O) in all wet paddy groups increased with piling time and with moisture content, with ranges of 11-289; 2-8; 36-374; and 4-26 ppm, respectively. The highest levels of moisture content in the paddy piles were in the range 28-30%wb. Nitrogen dioxide (NO(2)) concentrations were low in all paddy groups. The percentage of O(2) in the wet paddy groups decreased with piling time and moisture content (from 18.7% to 4.1%). This study suggested that hazardous gases could be emitted in moist paddy piles, and their concentrations could increase with increasing moisture content and piling time period. PMID:23047081

  4. 锚杆抗滑桩受力特性的光弹试验研究%Photoelastic experimental study on the mechanical characteristics of anchored piles

    Institute of Scientific and Technical Information of China (English)

    李寻昌; 门玉明; 翟越; 刘洪佳

    2011-01-01

    According to the research status of anchored pile, three types of anchored piles with different embedded depth are designed, based on epoxide resin as pile body and fixed rock mass, and photoelastic experiments are conducted to study the mechanical characteristics of anchored piles against landslide which are embedded in the rock mass. Through the observation of pile body and the isochromatic fringe variation of fixed rock mass, testing the change of anchor tension, the paper qualitatively gets the distribution rule of the internal forces, stress concentration problems of the pile, the displacement of the pile and the relation between anchor tension and the embedded depth, which is quite different from normal piles.%针对锚杆抗滑桩的研究现状,设计了三种不同嵌固深度的锚杆抗滑桩,桩体及嵌固岩体以环氧树脂作为模型材料,进行了光弹试验,来研究嵌固在岩体中锚杆抗滑桩的受力特性.通过观测桩体及嵌固岩体的等差线条纹变化规律,以及测试锚杆拉力的变化,定性得出了抗滑桩桩体内力的分布规律、桩体的应力集中问题及出现位置和锚杆拉力的变化与桩体嵌固深度的关系等问题,这与普通抗滑桩的受力特性有很大不同.

  5. 桩基负摩阻力时间效应试验研究%Experimental study of time effect of negative skin friction on pile

    Institute of Scientific and Technical Information of China (English)

    黄挺; 龚维明; 戴国亮; 郑金海; 徐国平

    2013-01-01

    由于黏土固结缓慢,桩基负摩阻力存在明显的时间效应,然而目前相关研究仍显不足。设计实施了能实现桩顶加载及较大超载值的单桩及双桩负摩阻力模型试验,桩周土采用砂土和软黏土夹层,测定了模型桩身应力、桩顶位移以及土体分层沉降随固结时间的变化。试验结果显示,沉降、负摩阻力具有明显的时间效应。土表超载作用下土体沉降带动桩沉降,桩与土体的沉降均表现出早期快、后期慢的趋势。试验加载初期,黏土夹层处的负摩阻力略小于砂层,但随土体固结而增长,其基本变化规律与沉降相同。因桩端砂土层沉降稳定迅速,中性点随桩身沉降增长略呈上移趋势。此外,相同荷载作用下桩间距较小的双桩,由于下拉力较小,其沉降较小。试验条件下,3D桩间距的负摩阻力群桩效应系数在0.71~0.77之间,6D桩间距时不存在负摩阻力群桩效应。%Due to the low rate of consolidation of clay, the time effect of negative skin friction on pile is obvious. However, the correlative research work is not deep enough and needs to be continued. The model tests of negative skin friction on pile and double pile are designed and conducted, which can apply pile load and large surcharge load on soil surface. And the soil in the test adoptes sand and clay interlayer. During the consolidation of clay, pile stress, pile settlement and settlement at each soil layer are measured. The results indicate that settlement and negative skin friction have significant time effect. The pile settlement increases with soil settlement under the surcharge load, which increases rapidly in early stage and slowly in later stage. The negative skin friction in clay is smaller than that in sand on the initial stage of loading, and the change rule is similar to the settlement. Since the settlement stability time of sand layer surrounding pile base is short, the

  6. Piles of objects

    KAUST Repository

    Hsu, Shu-Wei

    2010-01-01

    We present a method for directly modeling piles of objects in multi-body simulations. Piles of objects represent some of the more interesting, but also most time-consuming portion of simulation. We propose a method for reducing computation in many of these situations by explicitly modeling the piles that the objects may form into. By modeling pile behavior rather than the behavior of all individual objects, we can achieve realistic results in less time, and without directly modeling the frictional component that leads to desired pile shapes. Our method is simple to implement and can be easily integrated with existing rigid body simulations. We observe notable speedups in several rigid body examples, and generate a wider variety of piled structures than possible with strict impulse-based simulation. © 2010 ACM.

  7. Experimental investigation of pile-soil interaction under confining stress. Kosoku atsuryokuka no kui to jiban no sogo sayo ni kansuru jikkenteki kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, M.; Asano, T.; Koga, A.; Mizuno, T. (Okumura Corp., Osaka (Japan))

    1992-11-10

    As a problem concerning the interaction between the pile and the ground under the constrained pressure, the deep zone of the large diameter pile receiving the horizontal load was investigated. The behavior of the ground around the large diameter pile receiving the horizontal load is thought to be varied depending on the depth. The deep zone which is thought to be governed by the secondary behavior on the horizontal plane due to the loading effect was investigated by a simulation experiment to obtain the ground deformation and the fracture pattern. The results were as follows: (1) Concerning the displacement by the load, a break point appeared on the load-displacement curve when the load is small (displacement is less than 1 % of the pile diameter). However, when the displacement proceeded furthermore, the curve was straightened and no peak load value appeared, (2) When the displacement exceeded 10 % of the pile diameter, the slide took place. The slide propagated in the direction of loading as the load was increased, (3) Inside the sliding plane, the compressive strain is dominant, while outside, little compression strain occurs, (4) The direction along which the sliding plane appears is almost identical to the direction along which no relative expansion and shrinkage take place. 21 figs., 2 tabs.

  8. BEHAVIOR OF LATERALLY LOADED PILE

    OpenAIRE

    Ashish Mehta; P.D.Pachpor

    2010-01-01

    A finite element analysis is done to predict the responses for single pile subjected to lateral load in layered soils, with consideration of pile soil interaction. Pile and soil are simulated by Solid-3D element. In the computational model, contact surfaces between pile and soil are created. The displacements are determined for pile soil system with linearly constants and linearly varying with depth cases is considered. The engineering properties for soil and pile are considered as variable f...

  9. BEHAVIOR OF LATERALLY LOADED PILE

    Directory of Open Access Journals (Sweden)

    Ashish Mehta

    2010-12-01

    Full Text Available A finite element analysis is done to predict the responses for single pile subjected to lateral load in layered soils, with consideration of pile soil interaction. Pile and soil are simulated by Solid-3D element. In the computational model, contact surfaces between pile and soil are created. The displacements are determined for pile soil system with linearly constants and linearly varying with depth cases is considered. The engineering properties for soil and pile are considered as variable for analysis.

  10. 桩-土相互作用的模型试验研究%Model experimental study of pile-soil interaction

    Institute of Scientific and Technical Information of China (English)

    袁春辉

    2011-01-01

    Due to the presence of soil around the pile,the defect degree of pile can only be qualitatively analyzed by low stress-reflected wave method.The reverberation-ray matrix method was applied to fit coefficients of pile-bottom-soil at different compaction condition by model experiments in this paper,and some useful conclusions can be obtained after analyzing and comparing them.%应用回传射线矩阵法,通过模型试验,对不同压实状态下桩底土的系数进行拟合,通过分析对比得出一些有意义的结论。

  11. Basal Reinforced Piled Embankments

    NARCIS (Netherlands)

    Van Eekelen, S.J.M.

    2015-01-01

    A basal reinforced piled embankment consists of a reinforced embankment on a pile foundation. The reinforcement consists of one or more horizontal layers of geosynthetic reinforcement (GR) installed at the base of the embankment. The design of the GR is the subject of this thesis. A basal reinforce

  12. Container and waste pile standards for owners and operators of hazardous waste facilities: consolidated permit regulations--Environmental Protection Agency. Amendments to interim final rule.

    Science.gov (United States)

    1981-11-01

    The Environmental Protection Agency (EPA) is today promulgating amendments to the hazardous waste management regulations regarding the management of hazardous waste in containers and piles and associated permit regulations (40 CFR Part 264, Subparts I and L, and Part 122, Subpart B). These amendments better tailor the standards to the particular type of hazard posed by specific situations. The standards for containers are amended to waive the containment system requirements for wastes that do not contain free liquids, provided that the wastes are protected from contact with accumulated liquid. The standards for waste piles are amended to waive the containment system requirements for wastes that do not contain free liquids, provided that the pile is protected from precipitation by a structure and from surface water run-on and wind dispersal of the waste by the structure or some other means. The Agency believes these amendments believes these amendments will not reduce the level of protection of human health and the environment.

  13. Experimental Realization of Perfect Discrimination for Two Unitary Operations

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-Jun; HONG Zhi

    2008-01-01

    We experimentally demonstrate perfect discrimination between two unitary operations by using the sequential scheme proposed by Duan et al.[Phys. Rev. Lett. 98 (2007) 100503] Also, we show how to understand the scheme and to calculate the parameters for two-dimensional operations in the picture of the Bloch sphere.

  14. Bearing Behaviors of Stiffened Deep Cement Mixed Pile

    Institute of Scientific and Technical Information of China (English)

    WU Mai; ZHAO Xin

    2006-01-01

    A series of investigations were conducted to study the bearing capacity and load transfer mechanism of stiffened deep cement mixed (SDCM) pile.Laboratory tests including six specimens were conducted to investigate the frictional resistance between the concrete core and the cementsoil.Two model piles and twenty-four full-scale piles were tested to examine the bearing behavior of single pile.Laboratory and model tests results indicate that the cohesive strength is large enough to ensure the interaction between core pile and the outer cement-soil.The full-scale test results show that the SDCM piles exhibit similar bearing behavior to bored and cast-in-place concrete piles.In general, with the rational composite structure the SDCM piles can transmit the applied load effectively, and due to the addition of the stiffer core, the SDCM piles possess high bearing capacity.Based on the findings of these experimental investigations and theoretical analysis, a practical design method is developed to predict the vertical bearing capacity of SDCM pile.

  15. Pile Instrumentation Using Retrievable Sensors

    OpenAIRE

    Faisal H. Ali; Bujang B.K. Huat; Lee S. Kai

    2008-01-01

    Strain gauges are normally used to monitor the shortening or compression of pile during static pile load test. For concrete spun pile, the technique used either by incorporating high temperature-resistant strain gauges into the heat-cured production process of the spun piles or by installing an instrumented steel pipe into the hollow core of the spun piles followed by cement grout infilling. The former is extremely unpopular due to high cost of these gauges and the uncertainty over their abil...

  16. WAVE CURRENT FORCES ON THE PILE GROUP OF BASE FOUNDATION FOR THE EAST SEA BRIDGE, CHINA

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    On the basis of the two structures of the bridge foundation designed for the East Sea Bridge, the wave current forces on four types of oblique piles, the pile group and the single piles at different positions in the pile group considering the effect of the super structures were experimentally investigated. The relationship between the wave current forces and the associated wave parameters, and the comparison of the wave current forces on the pile groups and the single piles were systematically analyzed. The group effectiveness and the reduction coefficient for the wave current forces on the group were examined for engineering design.

  17. 40 CFR 264.554 - Staging piles.

    Science.gov (United States)

    2010-07-01

    ... operations as long as they are intended to prepare the wastes for subsequent management or treatment. (2) (b... waste no longer meets the definition of ignitable or reactive under § 261.21 or § 261.23 of this chapter... determine that continued operation of the staging pile: (i) Will not pose a threat to human health and...

  18. Numerical analysis of pile lateral behavior of pile supported embankment

    Institute of Scientific and Technical Information of China (English)

    荆志东; 刘力; 郑刚; 姜岩

    2008-01-01

    A finite difference numerical method was adopted to evaluate the pile lateral behavior of pile supported embankment. A published case history was used to verify the proposed methodology. By simulating the case history, the determination of parameters needed were verified. Then three embankments constructed on different ground conditions with different soil-pile relative stiffnesses were analyzed to study pile lateral behaviors including pile deflection and bending moment. The results show that pile deflections and bending moments induced by soil lateral deformation and embankment vertical load are different for piles at different positions under the same embankment. The relative stiffness between pile and soil affected by the properties of different reinforcing piles such as concrete pile and deep mixing method pile exert important effects on the pile lateral behavior and the pile’s failure modes. Consequently, it is necessary to consider the different piles lateral behaviors and possible failure modes at different positions and the different piles proprieties with different reinforcing methods in the embankment stability analysis.

  19. Soil-Pile Interaction in the Pile Vertical Vibration Based on Fictitious Soil-Pile Model

    OpenAIRE

    Guodong Deng; Jiasheng Zhang; Wenbing Wu; Xiong Shi; Fei Meng

    2014-01-01

    By introducing the fictitious soil-pile model, the soil-pile interaction in the pile vertical vibration is investigated. Firstly, assuming the surrounding soil of pile to be viscoelastic material and considering its vertical wave effect, the governing equations of soil-pile system subjected to arbitrary harmonic dynamic force are founded based on the Euler-Bernoulli rod theory. Secondly, the analytical solution of velocity response in frequency domain and its corresponding semianalytical solu...

  20. High Temperature Operational Experiences of Helium Experimental Loop

    International Nuclear Information System (INIS)

    The development of high temperature components of VHTR is very important because of its higher operation temperature than that of a common light water reactor and high pressure industrial process. The development of high temperature components requires the large helium loop. Many countries have high temperature helium loops or a plan for its construction. Table 1 shows various international state-of-the-art of high temperature and high pressure gas loops. HELP performance test results show that there is no problem in operation of HELP at the very high temperature experimental condition. These experimental results also provide the basic information for very high temperature operation with bench-scale intermediate heat exchanger prototype in HELP. In the future, various heat exchanger tests will give us the experimental data for GAMMA+ validation about transient T/H behavior of the IHX prototype and the optimization of the working fluid in the intermediate loop

  1. Policies for the Reduction of Slash Pile Burning in BC Forests

    OpenAIRE

    Kamp, Adam Roger

    2013-01-01

    In British Columbia, it is a common practice for forest companies to pile the unwanted fibre after harvest and burn the piles. There are numerous reasons why companies do this, but the primary reason is to reduce the forest fire risk. However, slash burning produces greenhouse gas emissions and local air contaminants. BC has also seen a significant reduction in the timber supply in interior regions due to the mountain pine beetle devastation. Thus, government and the industry are looking ...

  2. Largest Experimental Facility for Acetylene Production in Operation

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Scientists from the CAS Institute of Plasma Physics (IPP) completed in early November, 2004, a 2-megawatt experimental facility for acetylene production by coal plasma pyrolysis. The successful operation of the largest installation of the kind in the world confirms a new method for the large-scale industrialization of acetylene production.

  3. A simplified analysis method for piled raft and pile group foundations with batter piles

    Science.gov (United States)

    Kitiyodom, Pastsakorn; Matsumoto, Tatsunori

    2002-11-01

    A simplified method of numerical analysis has been developed to estimate the deformation and load distribution of piled raft foundations subjected to vertical, lateral, and moment loads, using a hybrid model in which the flexible raft is modelled as thin plates and the piles as elastic beams and the soil is treated as springs. Both the vertical and lateral resistances of the piles as well as the raft base are incorporated into the model. Pile-soil-pile, pile-soil-raft and raft-soil-raft interactions are taken into account based on Mindlin's solutions for both vertical and lateral forces. The validity of the proposed method is verified through comparisons with several existing methods for single piles, pile groups and piled rafts. Workable design charts are given for the estimation of the lateral displacement and the load distribution of piled rafts from the stiffnesses of the raft alone and the pile group alone. Additionally, parametric studies were carried out concerning batter pile foundations. It was found that the use of batter piles can efficiently improve the deformation characteristics of pile foundations subjected to lateral loads.

  4. 大直径扩底人工挖孔桩承载力研究%Experimental Research on Bearing Capacity of Large-Diameter Belled Pile

    Institute of Scientific and Technical Information of China (English)

    杨砚宗

    2014-01-01

    Based on a practical project in Wuhan, the bearing capacity of large-diameter belled pile has been studied by the limits of rock uniaxial compressive strength and deep plate loading test to determine the carrying capacity value of the bearing layer. We used standardized formulas to evaluate by two sets of test parameters characteristic values of pile capacity, and used static load tests to validate the estimated carrying capacity. The results showed that:the estimated carrying capacity of deep plate loading test, which is significantly greater than the uniaxial compressive strength test, is very similar with static load test. The plate loading test can accurately estimate the single pile loading capability, and that can provide a reliable reference for the design of large-diameter belled pile.%依托武汉某工程实例,对大直径扩底人工挖孔桩承载力进行了研究,通过岩石极限单轴抗压强度室内试验和深层载荷板试验确定持力层的承载力特征值,采用规范提供的计算公式,用两套试验参数对单桩承载力进行预估,并通过现场单桩载荷试验对计算结果进行验证。研究表明:深层载荷板试验参数预估单桩承载力特征值,明显大于岩石极限单轴抗压强度室内试验计算值,且前者与单桩静载荷试验结果更为接近,可准确预估单桩承载力,进而为后续大直径扩底挖孔桩设计提供可靠参考。

  5. Laterally Loaded Piles in Clay

    DEFF Research Database (Denmark)

    Christensen, Helle; Niewald, Gitte

    1992-01-01

    The ultimate lateral resistance of a pile element moved horizontally can be analyzed by the theory of plasticity. At a certain depth the movements around the pile are purely horizontal and upper bound solutions can be estimated theoretically under undrained circumstances. Model tests...... in the laboratory show ultimate resistances close to the estimated limits and p - y curves close to curves based on test results from full-scale piles. Rough and smooth piles with circular and square cross sections are investigated....

  6. Experimental investigation of geogrid-reinforced and pile-supported embankment on soils with medium-low compressibility%中低压缩性土地区桩承式加筋路堤现场试验研究

    Institute of Scientific and Technical Information of China (English)

    郑俊杰; 曹文昭; 董同新; 张军; 谢明星

    2015-01-01

    将桩承式加筋路堤技术应用于中低压缩性土地区高速铁路桥台和涵洞之间填方路基的处理,通过逐渐改变CFG桩桩长形成刚度均匀变化的地基加固区,严格控制线路纵向差异沉降.通过现场试验对桥台、涵顶和路基中心地基沉降进行了长期观测,同时对桩承式加筋路堤桩间土沉降、孔隙水压力、格栅上下表面土压力和格栅变形进行了长期监测分析.研究结果表明:桩承式加筋路堤可有效减小中低压缩性土地基沉降,总沉降小且很快趋于稳定;桩承式加筋路堤通过土拱效应和张拉膜效应将路堤荷载向桩帽传递,格栅下桩土应力比明显高于格栅上,张拉膜效应明显,格栅上桩土应力比接近1.0,土拱效应较弱;格栅在路肩处发挥的作用强于线路中心处.%The geogrid-reinforced and pile-supported embankment is adopted to treat the subgrade of high-speed railways between the bridge abutment and culvert on the soils with medium-low compressibility. The subgrade with uniformly variable stiffness is formed by varying the lengths of CFG piles gradually aiming at controlling the longitudinal differential settlement strictly. The settlements of bridge abutment, culvert and subgrade center are monitored based on full scale field tests. Meanwhile, the settlement of the surrounding soils of pile, the pore water pressure, the earth pressure above/below the geogrid, and the geogrid deformation are measured. The experimental results demonstrate that the total and layered settlements of the subsoils with medium-low compressibility are reduced effectively, and the total settlements are very small and reach the stable value soon. The embankment load is transferred to pile caps by the combined action of soil arching effect and tensioned membrane effect. The pile-soil pressure ratio below the geogrid is significantly larger than that above the geogrid, which suggests that an obvious tensioned membrane effect exists

  7. British Petroleum

    DEFF Research Database (Denmark)

    Andersen, Torben Juul; Andersen, Christine Bang

    2014-01-01

    The case deals with the rather tumultuous executive leadership changes of British Petroleum (BP) over the past decade from 2005 to 2014 in the wake of two dramatic incidents: The Texas City refinery explosion in 2005 and the explosion of the oil rig Deepwater Horizon in the Mexican Gulf in 2010...... guidelines and governance practices. The case captures the intricacies of corporate management and provides a realistic overview of the complexities that often surround leadership approaches and executive decisions. Hence, it can be used in various graduate and executive courses in strategic management......, leadership development and corporate governance that all grapple with issues of responsible ethical behaviour. This case is part of the CBS free case collection (visit www.thecasecentre.org/CBSfreecases for more information on the collection). This case can be downloaded by educators as a clean pdf...

  8. Soil-Pile Interaction in the Pile Vertical Vibration Based on Fictitious Soil-Pile Model

    Directory of Open Access Journals (Sweden)

    Guodong Deng

    2014-01-01

    Full Text Available By introducing the fictitious soil-pile model, the soil-pile interaction in the pile vertical vibration is investigated. Firstly, assuming the surrounding soil of pile to be viscoelastic material and considering its vertical wave effect, the governing equations of soil-pile system subjected to arbitrary harmonic dynamic force are founded based on the Euler-Bernoulli rod theory. Secondly, the analytical solution of velocity response in frequency domain and its corresponding semianalytical solution of velocity response in time domain are derived by means of Laplace transform technique and separation of variables technique. Based on the obtained solutions, the influence of parameters of pile end soil on the dynamic response is studied in detail for different designing parameters of pile. Lastly, the fictitious soil-pile model and other pile end soil supporting models are compared. It is shown that the dynamic response obtained by the fictitious soil-pile model is among the dynamic responses obtained by other existing models if there are appropriate material parameters and thickness of pile end soil for the fictitious soil-pile model.

  9. Proceedings of the 31. annual British Columbia mine reclamation symposium : rejuvenation through reclamation and operating for closure

    Energy Technology Data Exchange (ETDEWEB)

    Price, W.; Dixon, B.; Fraser, C.; Freberg, M.; Davidson, S.; Hart, B.; Jarman, P.; Wambolt, T.; Hamaguchi, B.; Howell, C.; Bellefontaine, K.; Bose, S. (eds.)

    2007-07-01

    This annual symposium fosters the exchange of information on mine reclamation, including metal mines, coal mines, placer operations, sand and gravel operations and quarry operations. The presentations addressed a wide variety of environmental and reclamation issues associated with mine development as well as the rehabilitation of lands disturbed by resource exploration. Studies have shown that it is possible to minimize or eliminate environmental damage in all types of terrain by using appropriate remedial methods such as revegetation, reforestation, soil conservation, resloping, and recontouring of the soil to return the ecosystem to a natural self-sustaining state. Revegetation and reforestation efforts usually involve the selection of appropriate species that will adapt to climatic and local soil conditions. The conference featured 23 presentations, of which 3 have been catalogued separately for inclusion in this database. refs., tabs., figs.

  10. Proceedings of the 31. annual British Columbia mine reclamation symposium : rejuvenation through reclamation and operating for closure

    International Nuclear Information System (INIS)

    This annual symposium fosters the exchange of information on mine reclamation, including metal mines, coal mines, placer operations, sand and gravel operations and quarry operations. The presentations addressed a wide variety of environmental and reclamation issues associated with mine development as well as the rehabilitation of lands disturbed by resource exploration. Studies have shown that it is possible to minimize or eliminate environmental damage in all types of terrain by using appropriate remedial methods such as revegetation, reforestation, soil conservation, resloping, and recontouring of the soil to return the ecosystem to a natural self-sustaining state. Revegetation and reforestation efforts usually involve the selection of appropriate species that will adapt to climatic and local soil conditions. The conference featured 23 presentations, of which 3 have been catalogued separately for inclusion in this database. refs., tabs., figs

  11. Nonlinear analysis of pile load-settlement behavior in layered soil

    Institute of Scientific and Technical Information of China (English)

    吕述晖; 王奎华; 张鹏; C. J. LEO3

    2015-01-01

    A simplified approach is presented to analyze the single pile settlement in multilayered soil. First, a fictitious soil−pile model is employed to consider the effect of layered soil beneath pile toe on pile settlement behavior. Two approximation methods are proposed to simplify the nonlinear load transfer function and simulate the nonlinear compression of fictitious soil−pile, respectively. On this basis, an efficient program is developed. The procedures for determining the main parameters of mathematical model are discussed. Comparisons with two well-documented field experimental pile loading tests are conducted to verify the rationality of the present method. Further studies are also made to evaluate the practicability of the proposed approach when a soft substratum exists, and the results suggest that the proposed method can provide a constructive means for assessing the settlement of a single pile for use in engineering design.

  12. Grouting for Pile Foundation Improvement

    OpenAIRE

    Van der Stoel, A.E.C.

    2001-01-01

    The aim of this research was to examine the use of grouting methods for pile foundation improvement, a generic term that is used here to define both foundation renovation (increasing the bearing capacity of a pile foundation that has insufficient bearing capacity) and foundation protection (safeguarding the piles of the foundation against possible damage resulting from underground construction activities in the vicinity). A full-scale test, of which the general set-up and consistency check ar...

  13. CENTRIFUGAL VIBRATION TEST OF RC PILE FOUNDATION

    Science.gov (United States)

    Higuchi, Shunichi; Tsutsumiuchi, Takahiro; Otsuka, Rinna; Ito, Koji; Ejiri, Joji

    It is necessary that nonlinear responses of structures are clarified by soil-structure interaction analysis for the purpose of evaluating the seismic performances of underground structure or foundation structure. In this research, centrifuge shake table tests of reinforced concrete pile foundation installed in the liquefied ground were conducted. Then, finite element analyses for the tests were conducted to confirm an applicability of the analytical method by comparing the experimental results and analytical results.

  14. Effect of Operating Conditions on CSTR performance: an Experimental Study

    Directory of Open Access Journals (Sweden)

    Mohd Danish

    2015-02-01

    Full Text Available In this work, Saponification reaction of ethyl acetate by sodium hydroxide is studied experimentally in a continuous stirred tank reactor at 1 atmospheric pressure. The aim of this study is to investigate the influence of operating conditions on the conversion and specific rate constant. The parameters considered for analysis are temperature, feed flow rate, residence time, volume of reactor and stirrer rate. The steady state conversion of 0.45 achieved after a period of 30 minutes. Conversion decreases with increase of reactant flow rate due to decrease of residence time. The stirrer rate has a positive effect on the conversion and rate constant. Specific rate constant and conversion increase with temperature within the studied temperature range. Within the range of reactor volume selected for analysis, conversion increases with increase in reactor volume. The results obtained in this study may be helpful in maximizing the conversion of ethyl acetate saponification reaction at industrial scale in a CSTR.

  15. Pressured Grouting Method (PGM) in Pile Engineering

    Institute of Scientific and Technical Information of China (English)

    吴兴序; 于志强; 王旭

    2002-01-01

    Application of pressured grouting method (PGM) in pile engineering can tackle problems encountered during construction of bored piles. Bearing capacity of piles can be increased through compaction of subsoils around piles. This paper reports research efforts of this technique by the pile research team in Southwest Jiaotong University in last decade with respect to the construction process, test findings, and primary research conclusions. The social-economical benefits of this method and application market in pile engineering are also analyzed.

  16. British Sign Name Customs

    Science.gov (United States)

    Day, Linda; Sutton-Spence, Rachel

    2010-01-01

    Research presented here describes the sign names and the customs of name allocation within the British Deaf community. While some aspects of British Sign Language sign names and British Deaf naming customs differ from those in most Western societies, there are many similarities. There are also similarities with other societies outside the more…

  17. Measurements of Operational Wind Turbine Noise in UK Waters.

    Science.gov (United States)

    Cheesman, Samuel

    2016-01-01

    The effects of wind farm operational noise have not been addressed to the same extent as their construction methods such as piling and drilling of the foundations despite their long operational lifetimes compared with weeks of construction. The results of five postconstruction underwater sound-monitoring surveys on wind farms located throughout the waters of the British Isles are discussed. These wind farms consist of differing turbine power outputs, from 3 to 3.6 MW, and differing numbers of turbines. This work presents an overview of the results obtained and discusses both the levels and frequency components of the sound in several metrics.

  18. Measurements of Operational Wind Turbine Noise in UK Waters.

    Science.gov (United States)

    Cheesman, Samuel

    2016-01-01

    The effects of wind farm operational noise have not been addressed to the same extent as their construction methods such as piling and drilling of the foundations despite their long operational lifetimes compared with weeks of construction. The results of five postconstruction underwater sound-monitoring surveys on wind farms located throughout the waters of the British Isles are discussed. These wind farms consist of differing turbine power outputs, from 3 to 3.6 MW, and differing numbers of turbines. This work presents an overview of the results obtained and discusses both the levels and frequency components of the sound in several metrics. PMID:26610955

  19. Experimental Design for the INL Sample Collection Operational Test

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G.; Piepel, Gregory F.; Matzke, Brett D.; Filliben, James J.; Jones, Barbara

    2007-12-13

    This document describes the test events and numbers of samples comprising the experimental design that was developed for the contamination, decontamination, and sampling of a building at the Idaho National Laboratory (INL). This study is referred to as the INL Sample Collection Operational Test. Specific objectives were developed to guide the construction of the experimental design. The main objective is to assess the relative abilities of judgmental and probabilistic sampling strategies to detect contamination in individual rooms or on a whole floor of the INL building. A second objective is to assess the use of probabilistic and Bayesian (judgmental + probabilistic) sampling strategies to make clearance statements of the form “X% confidence that at least Y% of a room (or floor of the building) is not contaminated. The experimental design described in this report includes five test events. The test events (i) vary the floor of the building on which the contaminant will be released, (ii) provide for varying or adjusting the concentration of contaminant released to obtain the ideal concentration gradient across a floor of the building, and (iii) investigate overt as well as covert release of contaminants. The ideal contaminant gradient would have high concentrations of contaminant in rooms near the release point, with concentrations decreasing to zero in rooms at the opposite end of the building floor. For each of the five test events, the specified floor of the INL building will be contaminated with BG, a stand-in for Bacillus anthracis. The BG contaminant will be disseminated from a point-release device located in the room specified in the experimental design for each test event. Then judgmental and probabilistic samples will be collected according to the pre-specified sampling plan. Judgmental samples will be selected based on professional judgment and prior information. Probabilistic samples will be selected in sufficient numbers to provide desired confidence

  20. A data-driven approach to pile-up at high luminosity

    CERN Document Server

    Hautmann, F

    2015-01-01

    We discuss recent results on pile-up based on a data-driven jet-mixing method. We illustrate prospects for experimental searches and precision studies in high pile-up regimes at high-luminosity hadron colliders, showing how the jet mixing approach can be used, also outside tracker acceptances, to treat correlation observables and effects of hard jets from pile-up.

  1. 基于透明土材料的异形桩拔桩过程对比模型试验%Comparative experimentation on pulling process of profiled pile by using transparent soil

    Institute of Scientific and Technical Information of China (English)

    曹兆虎; 孔纲强; 周航; 孙学谨

    2014-01-01

    With the development of underground space,pulling out problems of the existing pile and its impact areas become more and more prominent.However,the researches focused on displacement field and impact areas of pile pulling out process were relatively little,not to mention the study about profiled pile.Base on transparent soil material and PIV (Particle Image Velocimetry)technique,experiment on pulling process of the belled wedge pile was carried out,and the displacement field of the pile surrounding soil,and impact areas during pile pulling out process were non-intrusively measured.In order to conduct comparative analysis,experiment on the equal cross-section pile and the tapered pile with the same concrete usage was also taken.The research results show that the impact areas of belled wedge pile are obviously larger than those of equal section piles and tapered piles, of which the value is nearly 2.0 times of those of equal section piles.In the process of pulling out belled wedge piles,the horizontal displacement of the tapered pile is larger than that of the equal section pile,while the verti-cal displacement of the tapered pile is smaller than that of the equal section pile.%随着地下空间的逐步开发,既有桩基拔除问题及其拔桩过程对周围构件物影响的问题日渐突出;针对拔桩过程中桩对周围土体的位移场及影响范围的研究相对较少,而针对异形桩的研究更少。基于透明土材料和PIV(Particle Image Ve-locimetry)技术,开展扩底楔形桩的拔桩过程模型试验,测得拔桩过程中桩周土体的位移场变化规律以及拔桩影响范围;同时进行等直径圆形桩和楔形桩的拔桩模型试验并对比分析。研究结果表明:扩底楔形桩的拔桩扰动范围明显比楔形桩和等直径圆形桩大,其数值接近等直径圆形桩的2.0倍;楔形桩拔桩过程中水平向位移扰动比等直径圆形桩大,竖向位移扰动比等直径圆形桩小。

  2. Decommissioning and dismantling of 305-M test pile at the Savannah River Plant

    International Nuclear Information System (INIS)

    The 305-M Test Pile was started up at the Savannah River Plant in 1952 and operated until 1981. The pile was used to measure the uranium content of reactor fuel. In 1984 work began to decommission and dismantle the pile. Extensive procedures were used that included a detailed description of the radiological controls and safety measures. These controls allowed the job to be completed with radiation doses as low as reasonably achievable

  3. Pile-Reinforcement Behavior of Cohesive Soil Slopes: Numerical Modeling and Centrifuge Testing

    Directory of Open Access Journals (Sweden)

    Liping Wang

    2013-01-01

    Full Text Available Centrifuge model tests were conducted on pile-reinforced and unreinforced cohesive soil slopes to investigate the fundamental behavior and reinforcement mechanism. A finite element analysis model was established and confirmed to be effective in capturing the primary behavior of pile-reinforced slopes by comparing its predictions with experimental results. Thus, a comprehensive understanding of the stress-deformation response was obtained by combining the numerical and physical simulations. The response of pile-reinforced slope was indicated to be significantly affected by pile spacing, pile location, restriction style of pile end, and inclination of slope. The piles have a significant effect on the behavior of reinforced slope, and the influencing area was described using a continuous surface, denoted as W-surface. The reinforcement mechanism was described using two basic concepts, compression effect and shear effect, respectively, referring to the piles increasing the compression strain and decreasing the shear strain of the slope in comparison with the unreinforced slope. The pile-soil interaction induces significant compression effect in the inner zone near the piles; this effect is transferred to the upper part of the slope, with the shear effect becoming prominent to prevent possible sliding of unreinforced slope.

  4. Review article: review of behavioral operations experimental studies of newsvendor problems for operating room management.

    Science.gov (United States)

    Wachtel, Ruth E; Dexter, Franklin

    2010-06-01

    Operating room (OR) managers must plan staffing in the face of uncertain demand for OR time. Planning too much staffing results in underutilized OR time. Planning too little staffing causes overutilized time, which is approximately twice as expensive as underutilized time. Deciding how much staffing to plan for an OR is analogous to the classic newsvendor problem in operations research. A newsvendor must decide how much product to order based on its cost c and sales price p, plus estimates of the uncertain future demand for the product. The newsvendor problem has a simple mathematical solution. The correct amount of product to order is the (p - c)/p quantile of the demand for the product. This optimal order quantity is analogous mathematically to the number of hours of OR time for which staffing should be planned. We performed a systematic review of the behavioral operations experimental literature on newsvendor problems relevant to OR management. Student volunteers participating in experimental studies have great difficulty knowing how much product to order, given c, p, and the demand distribution. Decision making is only modestly improved by more frequent feedback. Even scores of rounds of ordering are insufficient for much learning to occur. Suboptimal decisions result from innate psychological biases. Students anchor on mean demand, make insufficient adjustments, and rely disproportionately on the most recent demand values. The behavior of OR managers who plan staffing for the OR is analogous to that of students participating in a newsvendor experiment. Month after month, an OR manager will plan too little staffing for the surgeon who consistently ends the day late and too much staffing for the surgeon who consistently does not fill an OR. Experimental studies of the newsvendor problem provide mechanistic insights into the reasons that OR managers make poor decisions when planning OR staffing. The students face no organizational factors or personality issues

  5. Grouted Pile and Its Bearing Capacity

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The grouting method applied in bored pile is an improvement to the conventional bored pile. Load tests have proved that grouting under the bored pile tip is an effective method to enhance the bearing capacity of the pile and to reduce the pile settlement. In this paper, the grouting technology is described and pile-load test results are discussed. In order to put the grouting method into design practice, the authors analyze the working mechanism of soil compaction. And, based on the theory of cavities expansion in soil mass, approximate formulae are proposed for estimating the bearing capacity of the grouted pile. The theoretical prediction agrees well with the load test results.

  6. 3D FEM Numerical Simulation of Seismic Pile-supported Bridge Structure Reaction in Liquefying Ground

    Directory of Open Access Journals (Sweden)

    Ling XianZhang, Tang Liang and Xu Pengju

    2011-04-01

    Full Text Available This study examines the establishment of liquefied ground pile-soil-bridge seismic interaction analysis of three-dimensional finite element analysis method for the simulation of liquefied ground shaking table test of pile-soil seismic interaction analysis, undertake OpenSees finite element based numerical simulation platform, for the shaking table test based on two-phase saturated porous media, Comparative numerical and experimental results, detailed test pile dynamic response of bridge structure and dynamic properties, especially liquefaction pore pressure, liquefaction of pile foundation and the dynamic response of the free field. Finite element method can reasonably predict the site of pore pressure, dynamic response; despite the conventional beam element simulation of pile, pile dynamic response can still accurately simulated.

  7. Non-probabilistic fuzzy reliability analysis of pile foundation stability by interval theory

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Randomness and fuzziness are among the attributes of the influential factors for stability assessment of pile foundation.According to these two characteristics, the triangular fuzzy number analysis approach was introduced to determine the probability-distributed function of mechanical parameters. Then the functional function of reliability analysis was constructed based on the study of bearing mechanism of pile foundation, and the way to calculate interval values of the functional function was developed by using improved interval-truncation approach and operation rules of interval numbers. Afterwards, the non-probabilistic fuzzy reliability analysis method was applied to assessing the pile foundation, from which a method was presented for nonprobabilistic fuzzy reliability analysis of pile foundation stability by interval theory. Finally, the probability distribution curve of nonprobabilistic fuzzy reliability indexes of practical pile foundation was concluded. Its failure possibility is 0.91%, which shows that the pile foundation is stable and reliable.

  8. Part 1: Logging residues in piles - Needle loss and fuel quality. Part 2: Nitrogen leaching under piles of logging residues

    International Nuclear Information System (INIS)

    Part 1: Experimental piles were built in three geographical locations during May-Sept. 1989. Logging residues consisted of 95% spruce and 5% pine. Height of the piles varied between 80 and 230 cm. Needles were collected by placing drawers under 40 randomely chosen piles. The drawers were emptied every two weeks during the storage period. Natural needle loss was between 18 and 32% of the total amount of needles after the first two months of storage. At the end of the storage period, 24-42% of the needles had fallen down to the drawers. At the end of the experiment the total needle fall was 95-100% in the shaken piles. According to the results of this study piles smaller than 150 cm had the most effective needle fall. Piles should be placed on open places where the air and sun heat penetrate and dry them. Needles were the most sensitive fraction to variations in precipitation compared to the other components, such as branches. Piles usually dried quickly, but they also rewet easily. This was especially true in the smaller piles. The lowest moisture content was measured at the end of June. The ash content in needles varied between 4 and 8%. 16 refs., 15 figs. Part 2: Three field experiments were equipped with no-tension humus lysimeters. Pairs of lysimeters with the same humus/field layer vegetation material were placed in pairs, one under a pile of felling residues and another in the open clear felling. Leaching of nitrogen as well as pH and electric conductivity in the leachate was followed through sampling of the leachate at regular intervals. The results from the investigation show that: * the amount of leachate was higher in lysimeters in the open clear felling, * pH in the leachate was initially lower under piles of felling residues, * the amount of nitrogen leached was higher in the open clear felling. Thus, storing of felling residues in piles during the summer season did not cause any increase in nitrogen leaching, which had been considered to be a risk

  9. Viscoelastic behavior of concrete pile

    Institute of Scientific and Technical Information of China (English)

    丁科; 唐小弟

    2008-01-01

    Based on constitutive theory of viscoelasticity,the viscoelastic behaviour of concrete pile was investigated.The influence of viscosity coefficient on the stress,displacement and velocity response was discussed.With the increase of viscosity coefficient,the amplitude of stress wave decreases,and the maximum value of the stress wave shifts to deeper position of the pile.In other words,the viscosity coefficient behaves as lag effect to stress wave.

  10. Experimental validation of modelling tools for a PEM fuel cell; Validation experimentale d'outils de modelisation d'une pile a combustible de type PEM

    Energy Technology Data Exchange (ETDEWEB)

    Boillot, M.

    2005-10-15

    In this work, a global view of the phenomena occurring in a PEM fuel cell is given. An original methodology was developed in order to determine the main parameters: thermodynamics, kinetics and transport phenomena. The gas flow in bipolar plates was characterised using experimental determination of residence time distributions and numerical simulations. Kinetics of both electrochemical reactions were analysed feeding the cell by diluted gases. In this part, the diffusion of reactants in the membrane electrodes assembly was taken into account. Finally, the relationship between humidity and electrical performance was investigated and the ohmic resistance of the cell was estimated. (author)

  11. DETERMINING DRIVING RESISTANCE WITH REBOUND OF PILE-TOP DURING PILE DRIVING

    Institute of Scientific and Technical Information of China (English)

    陈仁朋; 胡亚元; 陈云敏

    2001-01-01

    This paper presents a method to determine driving resistance with rebound of pile-top during pile driving. The soil around the pile shaft is assumed to be rigid-plastic, while that under the pile-tip is assumed to be ideally elastoplastic. The driving force acting on the pile-top is simplified to a triangular impact force. The kinematic equation of the pile-tip is established. From the one-dimensional wave equation, the movements of the pile-tip and pile-top are determined. The rebound at the pile-top can be written in a very concise form. It is shown that the shaft resistance makes the rebound at the pile-top decrease. In particular, when the pile is very long or the soil around the pile is very stiff, the decrease is very obvious.

  12. 76 FR 51947 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in the Columbia...

    Science.gov (United States)

    2011-08-19

    ... 1,016-mm) pile installations; therefore, noise levels recorded for projects in Alameda, California... Central Mexico to British Columbia, Canada. Their primary breeding range extends from Central Mexico to..., noise levels recorded for a project in Alameda, California that installed 40-inch (1,016-mm) steel...

  13. British Telecom and Project Universe

    Science.gov (United States)

    Childs, G. H. L.; Morrow, G.

    1983-07-01

    Factors influencing the emergence of local area network (LANs) are covered along with British Telecom's involvement in Project Universe, an experiment to produce high-speed data links between several LANs in the United Kingdom with the Orbital Test Satellite (OTS). Other functions of Project Universe include measuring the network components performance, developing procedures for using the system for computer-computer and terminal-computer operations, and investigating the use of LAN satellites for business and computer communications. British Telecom has been involved with Project Universe since its inception. A standard Videotex system has been connected to the Cambridge Ring, consequently providing Videotex terminals attached to the ring access to a special Universe Prestel system. Future goals include replacing the OTS with a new satellite with a terminal operating at 8-10 Mbit/s. Block diagrams are provided.

  14. Simulation analysis for O-cell test of pile and the interaction of upper pile and lower pile

    Institute of Scientific and Technical Information of China (English)

    ZHENG Ying-jie; ZHANG Ke-xu; ZHANG Er-qi

    2009-01-01

    In this paper, the soil-pile system of O-cell test of pile is simplified as an axi-symmetrie problem.By using aggregation of quadrilateral isoparametrie elements to simulate pile and soil, setting Goodman' s elements between pile and soils, a method of numerical simulation analysis on O-cell test of pile is presented with the consideration of nonlinear mechanical behavior of soils and pile-soil interface.The method is applied to the a-nalysis of a case of O-cell test of pile.The load-displacement curves and axial force curves of upper pile and lower pile obtained from the O-cell test of pile are fitted, and parameters of the mechanical model of soils and interface are determined.Analysis results validate that the numerical simulation analysis method put forward in this paper is applicable.Furthermore, the interaction and influence of upper pile and lower pile in the O-cell test are also studied with the method.The result shows that if load box is located in a soil layer with fine me-chanical behavior, the interaction of upper pile and lower pile in O-cell test can be ignored generally.

  15. A performance case study of energy pile foundation at Rosborg Gymnasium (Denmark)

    DEFF Research Database (Denmark)

    Pagola, Maria Alberdi; Jensen, Rasmus Lund; Poulsen, Søren Erbs

    2016-01-01

    The Rosborg Gymnasium building in Vejle (Denmark) is partially founded on 200 foundation pile heat exchangers (energy piles). The thermo-active foundation has supplemented the heating and free cooling needs of the building since 2011 (4,000 m2 living area). Operational data from the ground source...

  16. 40 CFR 270.18 - Specific part B information requirements for waste piles.

    Science.gov (United States)

    2010-07-01

    ... requirements for waste piles. 270.18 Section 270.18 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Permit Application § 270.18 Specific part B information requirements for waste piles. Except as otherwise provided in § 264.1, owners and operators of facilities that store or treat hazardous waste in waste...

  17. Analysis of Interaction Factors Between Two Piles

    Institute of Scientific and Technical Information of China (English)

    CAO Ming; CHEN Long-zhu

    2008-01-01

    A rigorous analytical method is presented for calculating the interaction factor between two identical piles subjected to vertical loads. Following the technique proposed by Muki and Sternberg, the problem is decomposed into an extended soil mass and two fictitious piles characterized respectively by Young's modulus of the soil and that of the difference between the pile and soil. The unknown axial forces along fictitious piles are determined by solving a Fredholm integral equation of the second kind, which imposes the compatibility condition that the axial strains of the fictitious piles are equal to those corresponding to the centroidal axes of the extended soil. The real pile forces and displacements can subequally be calculated based on the determined fictitious pile forces, and finally, the desired pile interaction factors may be obtained. Results confirm the validity of the proposed approach and portray the influence of the governing parameters on the pile interaction.

  18. Study and modelling of the in-pile densification of the UO2 and MOx nuclear oxides

    International Nuclear Information System (INIS)

    Amongst the many phenomena which take place in the course of the irradiation of UO2 or (U, Pu)O2 nuclear fuels, one of them involves the elimination of a fraction of the as-fabricated porosity. In-pile densification or sintering can reach 2.5%, i.e. approximately half the initial volume of pores is likely to disappear. Our literature survey indicates that the amplitude and kinetics of the phenomenon are both heavily dependent on the initial fuel microstructure. Micro-structural characterisation techniques of oxide fuels have therefore been developed in conjunction with quantitative image analysis methods. The ensuing methodology enables a quantitative comparison of micro-structural features in different fuels and has been applied to ascertaining the influence of the local fission rate and temperature on in-pile densification. It is thus revealed that in-pile operation eliminates a significant fraction of pores smaller than 3 microns in diameter. The experimental data generated has been used to set up a semi-empirical and a mechanistic model. The former is based on experimental results and is not essentially predictive. The inability of this model to predict the in-pile densification of oxide fuels is illustrated by the fact that the maximum fraction of pores that disappears is proportional to an empirical function of fission rate, and temperature. The proportionality factor appears to be difficult to correlate quantitatively to any given micro-structural feature. The model has however been applied to the interpretation of an in-pile densification experiment carried out in the Halden reactor (Norway). The latter model is mechanistic, i.e. it is based on the solution to a set of equations that describe the coupled temperature and radiation induced phenomena which occur in-pile. These can broadly be broken down into three categories: the fission fragment-pore interaction, the creation of point defects as the fission fragments slow down, and the diffusion of these

  19. EXPERIMENTAL STUDY ON BEARING PERFORMANCE OF STEEL PIPE PILE COMPOSITE FOUNDATION CONSTRUCTED BY TOP-DOWN METHOD UNDER VERTICAL LOADS%钢管桩逆作复合基础竖向承载性能试验研究

    Institute of Scientific and Technical Information of China (English)

    周儒夏; 龚维明; 杨乐; 柏平

    2012-01-01

    Model tests were designed to investigate the bearing capacity properties of composite steel pipe pile foundations in sandy soil.Results indicated that:To a single pile composite foundation,the load was totally carried by ground under the cap before sealing piles.Then,after sealing,the pile started to work and the pile-soil load share ratios were between 73.5%~92% before reaching ultimate bearing capacity.As vertical load increased continually to the capacity limit,the ratio reduced obviously.To a composite foundation with 8 steel pipe piles was tested,the attenuation gradient of axial load was larger in the middle and lower parts rather than the upper part during axial load transfer.The rates of the corner piles were biggest,then the side piles.The side frictional resistances developed gradually from the top to the bottom and the maximum value reached at the distance of 1.55 m below the top.At every load step,the resistances of the corner piles were greater than that of side piles.Moreover,the ultimate bearing capacity of the steel pipe pile composite foundation was significantly higher than that of the high-rise cap pile group foundation.%为了研究砂性土中钢管桩复合基础的承载特性,设计了模型桩系列试验。结果表明:对于单桩复合基础,封桩前阶段的荷载全部直接由承台底砂土承担,封桩后阶段桩体达到极限承载力之前,桩体分担的荷载占荷载增量的73.5%~92%,当桩的承载能力达到极限后,随着荷载的继续增加,桩分担的荷载比例较之前衰减明显,而土体分担的荷载比例增加。钢管桩八桩复合基础中,桩身轴力在桩身上部的衰减梯度明显小于中下部,角桩衰减速率最大,边桩次之;桩身摩阻力自上而下逐渐发挥,桩顶以下1.55 m处摩阻力达到最大;每级荷载作用下,角桩的侧阻力大于边桩。钢管桩群桩复合基础的竖向承载力远大于相对应的高承台群桩承载力。

  20. 全埋式抗滑桩倾覆破坏的室内模型试验研究%Model experimental study of toppling failure of fully-embedded anti-sliding pile

    Institute of Scientific and Technical Information of China (English)

    傅翔; 谢强; 张永兴; 邱鹏; 万仁锋

    2014-01-01

    基于室内推桩模型试验研究全埋式抗滑桩的倾覆破坏及受力变形特征:在满足各试验相似关系的前提下,建立室内模型试验池,观察模型桩从受荷到倾覆破坏的全过程。布设土压力盒、钢筋应变片、混凝土应变片及百分表,采用多通道动态测试系统,对桩身应变、钢筋应变、桩顶位移与土压力进行全方位的动态监测,分析模型桩的受力特性。研究结果表明,在滑坡推力作用下,桩顶水平位移与荷载之间大致呈现三折线关系,而且在锚固深度不够的情况下,桩的破坏形式为整体的刚性转动(倾覆破坏)。对土压力监测结果以及反推的桩身弯矩表明,桩身土压力分布曲线表现为上下小、中间大的近似抛物线分布,桩身最大土压力出现在桩中部;各级荷载作用下,桩身最大弯矩值出现在滑面处,桩顶及桩底弯矩值较小。%Based on the indoor-push-pile model experiments, the toppling failure mode and stress deformation characteristics of the fully-embedded anti-sliding pile are studied. Under the premise of the test similarly relation, the indoor model experiment-pool is established; and from loading to the toppling destruction of the whole process, the deformations of model pile are observed. Arranging earth pressure cells, steel strain gauges, concrete strain gauges, and dial indicators, and using a multi-channel dynamic measuring system to monitor pile strain, the steel strain, the displacement of pile top and the earth pressure, the mechanical characteristics of the model pile is analyzed. It is shown that, the relationship of load and lateral displacement of the pile top could be divided into 3 stages. When the anchorage depth is not enough to the monitoring results, the destruction form of the pile performs as a rigid rotation (toppling failure). The soil pressure of the pile is approximately parabolic. Maximum soil pressure is near the

  1. An experimental study of a VVER reactor's steam generator model operating in the condensing mode

    Science.gov (United States)

    Morozov, A. V.; Remizov, O. V.

    2012-05-01

    Results obtained from an experimental study of a VVER reactor's steam generator model operating in the condensing mode are presented. The obtained empirical dependence for calculating the power of heat exchangers operating in the steam condensation mode is presented.

  2. 液压高频振动沉桩的饱和土超静孔压及单桩静载特性试验研究%Experimental studies on pore pressure of saturated soils and bearing capacity of piles driven by high-frequency hydraulic vibrator

    Institute of Scientific and Technical Information of China (English)

    邓俊杰; 陈龙珠; 邢爱国; 宋春雨

    2011-01-01

    为解决常规锤击、电动中低频振动法进行桩基施工时引起较为严重的噪声、振动和增大电网负荷等问题,发达国家已在应用液压高频振动施工技术,但沉桩的土动力学机理以及单桩静力荷载-沉降特性等尚缺乏深入的室内外试验研究.利用大吨位液压高频振动锤,在某深厚饱和软土场地对直径500 mm、长度26~29 m的预应力管桩进行了沉桩施工试验,观测了邻近地基土超静孔压随沉桩深度而上升及其后续消散的过程;在休止期满后进行了单桩怪向静载荷试验,并将实测极限承载力与其它常规施工方法的进行了比较分析.试验结果对推广应用液压高频振动沉桩新技术,具有重要的学术和应用参考价值.%To solve the serious noise and vibration problems as well as the high pressure on the capacity of city power supply caused by the existing piling methods with falling hammers and low-frequency electric vibrators, a new piling technique using high-frequency hydraulic vibrators has been used in some developed european countries and the USA.The piling mechanism related to soil dynamics at high frequency and the bearing capacity of piles after installation with the hydraulic vibrators should be investigated in laboratory and construction sites.Using a high-frequency hydraulic vibrator manufactured by a Shanghai machinery company, pre-casted/pre-stressed concrete pipe piles with diameter of 500 mm and length of 26-29 m are driven into the saturated soft ground in the Minhang campus of Shanghai Jiaotong University in China, and the induced excess pore water pressures of adjacent soil at different depths are investigated for about one month.After the specified interruption period of 28 days after piling, the ultimate bearing capacity of each pile is studied by means of the conventional static loading tests and compared with that of piles installed with falling hammers and statically jetting.The experimental

  3. Centrifuge modelling of rigid piles in soft clay

    DEFF Research Database (Denmark)

    Klinkvort, R.T.; Poder, M.; Truong, P.;

    2016-01-01

    of this study is to employ centrifuge modelling in order to derive experimental p-y curves for rigid piles embedded in over-consolidated soft clay. A kaolin clay sample was prepared and pre-consolidated by applying a constant pressure at the soil surface, while different over-consolidation ratios were achieved...

  4. Design of anti-slide piles for slope stabilization in Wanzhou city, Three Gorges Area, China

    Science.gov (United States)

    Zhou, Chunmei; van Westen, Cees

    2013-04-01

    calculation of the anchor section in case of intensely weathered bedrock. The next component is a study on the subgrade retaining coefficient of anti-slide piles, which includes the definition and experimental methods used. The factors that have influence on the coefficient are discussed and the results of stress calculations in the anti-slide piles for different distributions of subgrade retaining coefficients are presented. Finally the differences between rigid piles and elastic pile are discussed and the elastic piles are considered to be more suitable for the landslide stabilization in the Wan Zhou area. The most important aspects for optimal design is the detailed knowledge of the features of soil and rock around the anchor part, which includes ground coefficients, uniaxial compressive strength, rock mass structure, fractures of bedrock, and weathering degree.

  5. Introduction to the experimental multipacting test stand / operating instructions

    CERN Document Server

    Holz, M

    2011-01-01

    In order to prevent multipacting when using high-intensity beams, the application of amorphous carbon coatings is under consideration. To investigate the eciency of the coatings to suppress electron cloud, a test stand for provoking multipacting has been set up using stand-alone SPS dipoles. This note gives a basic overview of the experimental set-up and a description of the measurement procedures. All the experiments that have been made with this set-up so far, encountered problems and their (possible) solutions are included.

  6. Instrumented model pile tests on sand plugs

    Energy Technology Data Exchange (ETDEWEB)

    Haaren, L.J.C. van; Verruijt, A. [Delft Univ. of Technology (Netherlands); Kolk, H.J. [Fugro Engineers B.V., Leidschendam (Netherlands)

    1995-12-31

    0pen ended piles develop internal frictional resistance between the internal soil plug end the pile wall during axial loading. Current pipe pile design practice assumes that the ultimate internal skin friction is of the same order of magnitude as the outer skin friction. This paper describes a series of laboratory pile load tests on instrumented model pipe piles, designed to investigate the development of plug stresses and skin friction along the plug length during pile loading. The piles contain sand columns of various relative densities and of different heights. The soil plugs are loaded to failure under fully drained conditions. The test data indicate that internal skin friction in sand can be substantially higher than assumed in conventional design practice. This finding could lead to significant economical savings on future pipe pile foundations in sand.

  7. Displacement and deformation analysis for uplift piles

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    On the assumptions that the shear resistance increases linearly with increasing shear displacement between the uplift pile and surrounding soil,that the axis force is distributed as parabola along the pile length,that elastic distortion occurs when the pile is loaded,that the displacement of pile is in accord with that of the soil,and that the uplift pile failure is regarded as the soil failure,arational calculation method was proposed for calculating the deformation,ultimate displacement and shear resistance of piles.The distributions of frictional resistance and the shear displacement along the pile length were obtained with the method.The comparisons were made between the measurement results and the present results.The present theoretical results agree well with the measurement results,with the average difference being less than 12% before failure.The comparisons show that the proposed method is reasonable for uplift design and engineering construction of piles.

  8. 14 CFR 91.319 - Aircraft having experimental certificates: Operating limitations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft having experimental certificates: Operating limitations. 91.319 Section 91.319 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... RULES Special Flight Operations § 91.319 Aircraft having experimental certificates:...

  9. Influence of vertical loads on lateral pile group response considering soil-pile-cap interactions

    Science.gov (United States)

    Hussien, Mahmoud N.; Tobita, Tetsuo; Iai, Susumu

    This paper presents the results of a numerical investigation conducted to study the effect of vertical loads on lateral response of a free head and a capped pile group in sand. A coupled soil-pile system is idealized through 2D finite elements with soil models idealized by a hyperbolic type multiple shear mechanism. The analysis focuses on the five piles in the middle row of a 3x5 pile group spaced at 3.92-pile diameters. The interaction between a pile and the surrounding soil in the 3D type is idealized in the 2D analysis using soil-pile interaction springs with a hysteretic non-linear load displacement relationship. The presence of vertical loads on free head piles increases the confining pressures in the sand deposit confined by the piles but the rate of increase in those outside the group is relatively small, resulting in the difference in a balance of lateral soil pressures acting at the back of and in front of individual piles. A vertical load applied to a group pile with a uniform vertical displacement of 0.1 pile diameter decreases the lateral resistance of the leading pile (pile 1) by 10 % and increases the lateral resistance of piles 3 and 5 by 14 and 35 %, respectively. The same trend with higher percentages of increase or decrease is observed in the capped pile group case.

  10. Experimental investigation on a single stiff pile subjected to long-term axial cyclic loading%刚性单桩竖向循环加载模型试验研究

    Institute of Scientific and Technical Information of China (English)

    陈仁朋; 任宇; 陈云敏

    2011-01-01

    刚性桩在高铁低矮路堤加固中广泛应用。利用浙江大学大型地基与边坡工程模型试验系统,开展了饱和粉土地基中刚性单桩动力加载大比例模型试验,对不同静偏荷载及循环荷载组合作用下的桩基性状进行了研究。通过模型桩身安装的各类传感器,对桩顶累积沉降、桩身轴力、桩–土界面孔压及正应力变化进行了监测。试验发现,循环剪切会引起桩–土界面土颗粒重排,导致桩–土界面孔压及有效应力状态发生改变。循环荷载比CLR对桩基累积沉降、桩侧应力状态发展影响显著。根据试验结果,对累积沉降发展规律进行了归纳,分析并讨论了桩侧应力状态变化机理。%Stiff pile-supported low embankments have been widely adopted in high-speed railway lines in China.Large-scale model tests are carried out to investigate the response of a single stiff pile subjected to axial dynamic loading in silts.Tests are conducted by means of the large foundation and slope engineering simulation system in Zhejiang University.Various combinations of static and cyclic loadings are applied in tests.The pile used in the tests are instrumented with load cells,pore pressure probes and pressure cells.The accumulated settlement,axial force,pore pressure and radial total stress along the pile are monitored.The test results indicate that the cyclic loading causes soil particle rearrangement,which leads to a change in stress state at soil-pile interface.The accumulated settlement and stresses acting on pile shaft are greatly influenced by the cyclic loading ratio(CLR).The development of the accumulated settlement with different CLRs is summarized and presented.The possible mechanisms responsible for stress changes at soil-pile interface are discussed.

  11. OF THE SLAB-PILE FOUNDATION

    Directory of Open Access Journals (Sweden)

    Ter-Martirosyan ZavenGrigorevich

    2012-10-01

    It is proven that the above properties produce a substantial impact onto the stress-strain state of soils that interact with the pile and the grid, and the impact values make it possible to assess the rigidity of the slab-pile foundation that is needed to solve the problems of the multiplicity of piles as well as the problems of distribution of the total load between the piles and the grid.

  12. Analysis of pile foundations under dynamic loads

    International Nuclear Information System (INIS)

    A method is presented for the analysis of pile foundations which are subjected to horizontal dynamic loads from earthquakes, airplane impact, gas explosion or other sources. The motion of the pile cap and the pile forces are computed. - The loads may be applied to the pile cap or directly to the piles (e.g. by earthquake wave motion). The soil may be stratified and is considered to be an elastic or visco-elastic medium. The piles are assumed vertical. The method makes use of an approximate fundamental solution for displacements caused by a dynamic point load in a layered visco-elastic medium. The approximation involves a discretization of the medium in the vertical direction. In horizontal directions the medium is treated by continuum theory. The soil medium supports each pile at about 10 to 20 nodes. A dynamic flexiblity matrix for the soil is derived which relates the elastic, damping and inertial forces of the soil to the displacements at each node. It includes effects of radiation damping. All piles are coupled through the soil flexibility matrix. The piles are modelled by beam elements. Transient response is computed using fast discrete Fourier transforms. The arrangement of the piles is arbitrary. However, simple and double symmetry can be accounted for by the computer program. When the pile arrangement is axisymmetric, the degrees of freedom can be reduced to only those of two piles per ring. The influence of the number of piles and the influence of the pile spacing on group stiffness and on pile forces is presented for two soil profiles. Dynamic effects on pile forces of a foundation for a reactor building are studied. They are significant when soils are soft. (orig.)

  13. Vision-based autonomous grasping of unknown piled objects

    International Nuclear Information System (INIS)

    Computer vision techniques have been used to develop a vision-based grasping capability for autonomously picking and placing unknown piled objects. This work is currently being applied to the problem of hazardous waste sorting in support of the Department of Energy's Mixed Waste Operations Program

  14. Retrofitting Of RCC Piles By Using Basalt Fiber Reinforced Polymer BFRP Composite Part 1 Review Papers On RCC Structures And Piles Retrofitting Works.

    Directory of Open Access Journals (Sweden)

    R. Ananda Kumar

    2015-01-01

    Full Text Available Abstract Retrofitting works are immensely essential for deteriorated and damaged structures in Engineering and Medical fields in order to keep or return to the originality for safe guarding the structures and consumers. In this paper different types of methods of retrofitting review notes are given based on the experimental numerical and analytical methods results on strengthening the Reinforced cement concrete RCC structures including RCC piles. Soil-pile interaction on axial load lateral load reviews are also presented. This review paper is prepared to find out the performance of basalt fibre reinforced polymer BFRP composite retrofitted reinforced cement concrete single end bearing piles.

  15. Experimental Study of the Ground Penetrating Radar Monitoring on the Integrity of Tamping Soil Cement Pile%夯实水泥土桩桩身完整性探地雷达检测技术试验研究

    Institute of Scientific and Technical Information of China (English)

    王海东; 张梦; 邓继平; 罗杰; 杨献章; 廖春芳

    2012-01-01

    针对复合地基柔性桩基桩身完整性难以检测的实际工程问题,提出了组合天线阵方式的探地雷达检测技术.通过对6根夯实水泥土桩桩长和桩身缺陷检测试验研究发现,桩长检测的最大平均相对误差为5.10%,桩身缺陷位置检测相对误差为5.45%,表明采用此技术对复合地基柔性桩基桩身完整性进行测定具有足够的可靠性,满足工程需要.通过对龄期、配合比、含水率和天线选择等影响因素的分析,得到了这些参数对检测质量的影响规律,并据此为工程应用提出了相应合理建议.%The combination of antenna array detection method of ground penetrating radar was put forward to solve the actual engineering problem that is difficult to monitor the integrity of the flexural pile composite foundation. The experiments of the lengths and defects of six tamping soil cement piles have shown that the maximum average relative error of pile lengths is 5. 10% and the relative error of the pile position of defects is 5. 45%. The results have indicated that there is enough reliability to determine the pile integrity by using the GPR method, which can meet the engineering needs. Furthermore, the age of cement, the ratio between soil and cement, moisture content were studied, and corresponding proposals for actual projects were presented.

  16. Experimental Results from Initial Operation of Plasma Injector 1

    Science.gov (United States)

    Howard, Stephen

    2010-11-01

    General Fusion has begun operation of its first full-scale plasma injector, designed to accelerate high density spheromak plasmas into the compression chamber of a proposed MTF reactor. The geometry of Plasma Injector 1 (PI-1) is that of a two stage coaxial Marshal gun with a conical converging accelerator electrodes, similar in shape to the MARAUDER device, while pulsed power is applied in the same configuration as the RACE device. PI-1 is 5 meters in length and 1.9 m in diameter at the expansion region where a high aspect ratio (4.4) spheromak is formed with a minimum lambda of 9 m-1. The acceleration/compression stage is 4 m long and tapers to a final outer diameter of 40 cm. PI-1 is now operating at 1 MJ of total capacitor power, which will be doubled again before it reaches its design parameters. Diagnostics include 3 interferometer chords, 21 magnetic probes (2 axis poloidal/toroidal), 13 fast photodiode chords, as well as one Thomson scattering chord, a visible light survey spectrometer, and a Langmuir triple probe. Electrode voltage and current are also monitored. So far spheromaks of poloidal flux exceeding 100 mWb have been formed in the expansion region, and spheromaks of 40-50 mWb have been formed and accelerated out the end of the accelerator into a flux conserving target chamber. Expansion region densities are typically ˜5 x10^14cm-3, while conditions in the target chamber have reached ne˜10^16cm-3, and lifetimes of 300 μs.

  17. Catastrophic model for stability analysis of high pile-column bridge pier

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    According to the engineering features of higher pile-column bridge pier in mountainous area, a clamped beam mechanical model was set up by synthetically analyzing the higher pile-column bridge pier buckling mechanism. Based on the catastrophe theory, the cusp catastrophe model of higher pile-column bridge pier was established by the determination of its potential function and bifurcation set equation, the necessary instability conditions of high pile-column bridge pier were deduced, and the determination method for column-buckling and lateral displacement of high pile-column bridge pier was derived. The comparison between the experimental and calculated results show that the calculated curves agree with testing curves and the method is reasonable and effective.

  18. 桩承式加筋路堤三维土拱效应试验研究%Experimental study of 3D soil arching in piled reinforced embankments

    Institute of Scientific and Technical Information of China (English)

    曹卫平; 胡伟伟

    2014-01-01

    桩承式加筋路堤受力性状比较复杂,土拱效应对路堤的承载变形性状具有重要影响。通过三维土拱效应模型试验,研究桩-土相对位移、路堤高度、桩帽净间距和水平加筋体拉伸强度等因素对桩土应力比及路堤沉降的影响。结果表明:土拱效应发挥程度与桩-土相对位移密切相关,存在一个临界桩-土相对位移使得桩土应力比达到最大值,该临界桩-土相对位移约为6~8 mm。路堤高度与桩帽净间距之比越大,桩土应力比越大,路堤顶面差异沉降越小;桩帽宽度与桩帽净间距之比越大,桩土应力比越大,路堤顶面差异沉降越小。设置水平加筋体能有效提高桩土应力比并减小路堤顶面沉降;路堤越低,水平加筋体对桩土应力比的提高作用及对路面沉降的减小作用越明显;水平加筋体拉伸强度越高,这种作用越明显。桩承式加筋路堤三维土拱效应等沉面高度与桩帽净间距之比约为3.5。%Soil arching has a notable influence on the behavior of piled reinforced embankment for its mechanically complex nature. A series of 3D model tests are conducted to explore the influence of the pile-soil relative displacement, embankment height, pile-cap spacing and horizontal reinforcement tension strength on the stress concentration ratio as well as the embankment settlement. The test results show that: soil arching is closely related to the pile-soil relative displacement and there exists a critical pile-soil relative displacement of approximate 6 to 8 mm which makes the stress concentration ratio reaching its maximum value. The bigger the ratio of embankment height is to the pile-cap clear spacing, the bigger the stress concentration ratio and the smaller the differential settlement on the surface of the embankment are;a bigger ratio of the cap width to the pile-cap clear spacing will result in a bigger stress concentration ratio and a smaller

  19. EXPERIMENTAL STUDY ON DYNAMIC CHARACTERISTICS OF COMPOSITE FOUNDATIONS OF RAMMED CEMENT-SOIL LOOP PILES WITH CFG CORES%CFG芯水泥土环组合桩复合地基动力特性试验研究

    Institute of Scientific and Technical Information of China (English)

    丁继辉; 冯俊辉; 张攀星; 全小娟

    2015-01-01

    For optimized pile foundation design,the concepts of cement-flyash-gravel pile (CFGP) and rammed cement-soil pile (RCSP) were combined in this study to form the rammed cement-soil loop pile with CFG cores (CFGCP-RCSLP).The static and dynamic characteristics of the CFGCP-RCSLP composite foundation were studied using in-situ tests.Test results show that with identical soil properties,pile length and pile spacing,the load-settlement curve of the CFGCP-RCSLP composite foundation demonstrates a clear linear relationship.The bearing capacity of the CFGCP-RCSLP composite foundation is 19.1% lower than the CFGP composite foundation,23.8% lower than that of the RCSP pile composite foundation,and 102% higher than a natural foundation.The blasting tests show that under same explosion energy and the arrangement of blast points,the dynamic characteristics of composite foundations are primarily related to soil properties,pile rigidity distribution and pilling load.The blast point location arrangement directly influences the distribution of peak acceleration along the pile body of CFGCP-RCSLP composite foundations,and the peak acceleration decreases significantly as the pilling load increases.%基于优化桩型的观点,将工法成熟的水泥粉煤灰碎石桩(简称CFGP)和夯实水泥土桩(简称RCSP)进行组合,设计CFG芯桩-水泥土环桩(简称CFGCP-RCSLP)组合桩复合地基,通过现场试验研究CFGCP-RCSLP组合桩复合地基的静力特性和动力特性.现场载荷试验表明,当土性、桩长、桩间距相同的情况下,CFGCP-RCSLP组合桩复合地基的荷载沉降曲线具有明显的线性关系,复合地基承载力比CFGP复合地基降低19.1%,比RCSP桩复合地基降低23.8%,比天然地基增加了102%.现场爆破试验表明,在爆炸能量、爆炸点位置相同条件下,复合地基的动力特性主要取决于土性、桩体刚度分布和堆载的大小.爆炸点的位置直接影响CFGCP-RCSLP组合桩复合地基中峰

  20. DRIVEN POLYSTRONG REINFORCED CONCRETE PILES AND NEW DESIGN OF PILE CAPS

    Directory of Open Access Journals (Sweden)

    I. I. Bekbasarov

    2015-01-01

    Full Text Available The paper presents constructional and technological features for manufacturing driven piles with variable strength of pile shaft. Economical efficiency of their production has been shown in the paper. The paper provides a pile cap design that ensures perception of hammer impacts with the help of lateral edges of the pile cap. Driven reinforced concrete piles which are manufactured from three shaft sections having various strength have been proposed in the paper. Material strength (concrete grade and diameter of bars and length of shaft sections are given on a case by case basis in accordance with nature and rate of stresses in piles during their driving process. Manufacturing of polystrong piles provides an opportunity to select them for a particular construction site with due account of their preservation during driving process.A pile cap has been developed that as opposed to existing analogous designs makes it possible to transmit impact efforts from a hammer to the pile through lateral surface of its head part. The pile cap provides the possibility to increase an area for perception of hammer impact efforts by the pile and in doing so it is possible significantly to reduce a damage risk and destruction of pile concrete during its driving. Application of polystrong piles and their driving with the help of new pile cap are considered as a basis for defect-free and resource-saving technology for pile foundations in the construction.

  1. Pullout capacity of batter pile in sand.

    Science.gov (United States)

    Nazir, Ashraf; Nasr, Ahmed

    2013-03-01

    Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Also most of retaining walls are subjected to horizontal forces and bending moments, these forces are due to earth pressure. For foundations in such structures, usually a combination of vertical and batter piles is used. Little information is available in the literature about estimating the capacity of piles under uplift. In cases where these supporting piles are not vertical, the behavior under axial pullout is not well established. In order to delineate the significant variables affecting the ultimate uplift shaft resistance of batter pile in dry sand, a testing program comprising 62 pullout tests was conducted. The tests are conducted on model steel pile installed in loose, medium, and dense sand to an embedded depth ratio, L/d, vary from 7.5 to 30 and with various batter angles of 0°, 10°, 20°, and 30°. Results indicate that the pullout capacity of a batter pile constructed in dense and/or medium density sand increases with the increase of batter angle attains maximum value and then decreases, the maximum value of Pα occurs at batter angle approximately equal to 20°, and it is about 21-31% more than the vertical pile capacity, while the pullout capacity for batter pile that constructed in loose sand decreases with the increase of pile inclination. The results also indicated that the circular pile is more resistant to pullout forces than the square and rectangular pile shape. The rough model piles tested is experienced 18-75% increase in capacity compared with the smooth model piles. The suggested relations for the pullout capacity of batter pile regarding the vertical pile capacity are well predicted.

  2. Pullout capacity of batter pile in sand

    Directory of Open Access Journals (Sweden)

    Ashraf Nazir

    2013-03-01

    Full Text Available Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Also most of retaining walls are subjected to horizontal forces and bending moments, these forces are due to earth pressure. For foundations in such structures, usually a combination of vertical and batter piles is used. Little information is available in the literature about estimating the capacity of piles under uplift. In cases where these supporting piles are not vertical, the behavior under axial pullout is not well established. In order to delineate the significant variables affecting the ultimate uplift shaft resistance of batter pile in dry sand, a testing program comprising 62 pullout tests was conducted. The tests are conducted on model steel pile installed in loose, medium, and dense sand to an embedded depth ratio, L/d, vary from 7.5 to 30 and with various batter angles of 0°, 10°, 20°, and 30°. Results indicate that the pullout capacity of a batter pile constructed in dense and/or medium density sand increases with the increase of batter angle attains maximum value and then decreases, the maximum value of Pα occurs at batter angle approximately equal to 20°, and it is about 21–31% more than the vertical pile capacity, while the pullout capacity for batter pile that constructed in loose sand decreases with the increase of pile inclination. The results also indicated that the circular pile is more resistant to pullout forces than the square and rectangular pile shape. The rough model piles tested is experienced 18–75% increase in capacity compared with the smooth model piles. The suggested relations for the pullout capacity of batter pile regarding the vertical pile capacity are well predicted.

  3. Development of the Testing System for Multi-functional Pile Foundation%新型多功能桩基试验系统的研制

    Institute of Scientific and Technical Information of China (English)

    戴兵; 张瑜; 段梦兰; 袁志林

    2012-01-01

    The stability of pile foundation has great effect on the operating safety of jack-up drilling platform. There is little research on the stability of pile foundation at home and lack of the corresponding test device. Therefore, a new type of multi-functional testing system for pile foundation was designed. The system can conduct the common experimental study of pile foundation stability, such as pile-inserting, pile-pulling and piercing in self-elevating drilling platform, providing a desirable testing platform for the precise prediction of pile-inserting depth and pile-pulling resistance and the intensive study of piercing mechanism. After installation of washingout pile system, the analysis of pile washing-out effect in pile-pulling in jack-up drilling platform and study of active formation penetration mechanism with washing-out pile can be conducted. Therefore, the function of the testing system is extended. A quick simulation of the interaction between the foundation and the subsea soil in the operating process of the jack-up platform can be carried out. As a result the powerful technological support is provided for determination of whether the jack-up platform can work in some area, especially in strange areas.%桩基稳性对自升式钻井平台作业安全影响很大。国内针对桩基稳性的研究较少,更缺乏相应的试验装置。为此,设计了新型多功能桩基试验系统。该系统可以开展自升式钻井平台插桩、拔桩和穿刺等常见的桩基稳性试验研究,为自升式钻井平台在作业区域插桩深度、拔桩阻力的准确预测以及穿刺机理的深入研究提供了一个良好的试验平台;加装冲桩系统后,还可以开展自升式钻井平台拔桩时的冲桩效果分析和采用冲桩的方式主动穿透硬地层机理研究,扩展了试验系统的功能;能方便、快速地模拟自升式钻井平台作业过程中桩基与海土的相互作用,从而为自升式钻井平台能

  4. Retrofitting Of RCC Piles By Using Basalt Fiber Reinforced Polymer BFRP Composite Part 1 Review Papers On RCC Structures And Piles Retrofitting Works.

    OpenAIRE

    R. Ananda Kumar; Dr. C. Selvamony; A. Seeni; Dr. T. R. Sethuraman

    2015-01-01

    Abstract Retrofitting works are immensely essential for deteriorated and damaged structures in Engineering and Medical fields in order to keep or return to the originality for safe guarding the structures and consumers. In this paper different types of methods of retrofitting review notes are given based on the experimental numerical and analytical methods results on strengthening the Reinforced cement concrete RCC structures including RCC piles. Soil-pile interaction on axial load lateral lo...

  5. Behaviour of Single Pile in Reinforced Slope Subjected to Inclined Load

    Directory of Open Access Journals (Sweden)

    Dr. A. I. Dhatrak

    2016-09-01

    Full Text Available Deep foundations, including driven piles, are used to support vertical loads of structures and lateral forces. Typical structures subjected to lateral loads include bridge abutments, transmission tower, sand offshore platforms. Traffic, wind, wave, and seismic forces are common types of lateral loads subjected to pile foundations. The present work is focused on understanding the lateral load capacity of vertical piles located near crest of the slope and subjected to the lateral and inclined loads. The experimental investigation was carried out to study the effect of reinforcing an earth slope on the inclined loading behavior of a single vertical pile located near the slope. Layers of geogrid were used to reinforce a sandy slope of 1V:2H. The parametric studies were performed by varying the length of pile(L, angle of inclination of load (θ, number of geogrid reinforcement (Nr and crest distance. It was observed that the lateral load capacity of pile depends upon these parameters. The lateral load capacity of pile increases with increase in inclination of load, length of pile(L, number of geogrid reinforcement (Nr and crest distance.

  6. Pile Load Capacity – Calculation Methods

    Directory of Open Access Journals (Sweden)

    Wrana Bogumił

    2015-12-01

    Full Text Available The article is a review of the current problems of the foundation pile capacity calculations. The article considers the main principles of pile capacity calculations presented in Eurocode 7 and other methods with adequate explanations. Two main methods are presented: α – method used to calculate the short-term load capacity of piles in cohesive soils and β – method used to calculate the long-term load capacity of piles in both cohesive and cohesionless soils. Moreover, methods based on cone CPTu result are presented as well as the pile capacity problem based on static tests.

  7. Pile Model Tests Using Strain Gauge Technology

    Directory of Open Access Journals (Sweden)

    Krasiński Adam

    2015-09-01

    Full Text Available Ordinary pile bearing capacity tests are usually carried out to determine the relationship between load and displacement of pile head. The measurement system required in such tests consists of force transducer and three or four displacement gauges. The whole system is installed at the pile head above the ground level. This approach, however, does not give us complete information about the pile-soil interaction. We can only determine the total bearing capacity of the pile, without the knowledge of its distribution into the shaft and base resistances. Much more information can be obtained by carrying out a test of instrumented pile equipped with a system for measuring the distribution of axial force along its core. In the case of pile model tests the use of such measurement is difficult due to small scale of the model.

  8. Erective Sea Embankment with PCC Piles

    Institute of Scientific and Technical Information of China (English)

    LIU Han-long; FEI Kang; DENG An; ZHANG Ting

    2005-01-01

    The sea embankment is a critical civil works in marine and coastal engineering. In this study, an innovative technique is proposed for constructing erective sea embankments. In the construction of sea embankments, this technique integrates PCC pile installation, PVDs drainage systems, and geotextile reinforcements, resulting in sea embankments with PCC piles. In the application of a sea embankment with PCC piles, PCC piles are employed as the retaining structures;the soft sea ground inside PCC piles is drained and improved by PVDs and vacuum-surcharge combined preloading; geotextile-reinforced backfills lying over the improved soft ground form the embankment body. Brief descrptions of the fundamentals, design and construction of the sea embankment with PCC piles are presented. A case study on the stability of sea embankment with PCC piles is presented as well.

  9. Introduction to Single Piles under Lateral Loading

    DEFF Research Database (Denmark)

    Augustesen, Anders; Ibsen, Lars Bo

    The purpose of this chapter is to give a short introduction to single piles subjected to lateral loading. First, the observed behaviour of laterally loaded piles is described, i.e. the effects of loading conditions, installation procedure, pile type etc. on pile behaviour are presented (section 1.......2). The description is based on results of laboratory tests, full-scale field tests as well as numerical investigations presented in literature. Second, general methods that attempt to model lateral pile response are discussed in section 1.4. Third, focus is paid to a widely used method for prediction of the response...... of a lateral loaded pile, namely the Winkler approach in which the pile is modelled as an elastic beam on an elastic foundation (section 1.5). The soil response and thereby the elastic foundation is represented by springs with nonlinear behaviour (p-y curves). In section 1.6 different types and formulations...

  10. 地震激励下冻土-液化土-单桩共同作用试验研究%Experimental study on frozen soil-liquefiable soil-single pile interaction during earthquakes

    Institute of Scientific and Technical Information of China (English)

    杨润林; 杨朝晖; 乔春明; 张小雨

    2014-01-01

    Liquefaction-induced lateral gound spreading can result in excessive lateral displacement, even failure of piles, nevertheless the situation may be somewhat different in frozen ground. Shaking table tests are conducted with the purpose of investigating the corresponding influence. The soil profile, contained in a large flexible box, consists of a horizontally saturated sand layer overlaid with a simulated frozen soil layer. The simulated steel-pipe pile is embeded in these two soil layers, with a supplemental lumped mass at the top. The device is excited through several amplitude-scaled seismic waves with different levels. During the tests the strain of the pile, the displacements of the pile and the frozen-soil layer, and the pore water pressure in the sand are recorded. Some important conclusions can be drawn. When liquefaction occurs, the frozen-soil layer can suppress the pore water drains from the saturated sand soils and make the pore water pressure increase continuously. Hence, the liquefaction has the tendency to accelerate and the lateral displacement of the pile may increase significantly. With the increasing levels of seismic excitation, the position on the frozen crust corresponding to the contact surface of the frozen-soil layer and the pile may be damaged because of squeezing, and thus the contact surface cannot be maintained effectively any longer. The sudden changes in the lateral deformation of the pile occour at the positions corresponding to the bottom and the top surface of the frozen crust, and consequently these positions on the pile can be easily damaged.%地基土地震液化诱发的侧向扩展可导致桩基侧移过大甚至失效破坏,但如果场地存在冻土层,情况则变得复杂。通过试验研究了在地震作用下冻土、液化土和单桩三者之间的相互作用,分析了由于存在冻土层这一因素对地基液化和桩基承载性能的影响。试验中土体盛放在一个柔性模型箱当中,分为

  11. Norwegian supply of goods and services to the British offshore sector

    International Nuclear Information System (INIS)

    Representatives from ten Norwegian companies in the offshore supplies industry were interviewed to explore the opportunities and barriers they had experienced in their effort to enter the British offshore sector. The interviews revealed that there are mainly four reasons why British sector is regarded as a favorable market: British sector is a natural homemarket, buyers operate both on the British and the Norwegian sector, the British sector can be a ''door-opener'' to the rest of the English speaking world, and finally the British sector is a market of considerable size. The companies had mainly encountered three types of barriers: British culture/communication problems, heavy competition from British suppliers, and protectionism. The report is concluded by summarizing what we believe are the critical success factors for entering the British sector. Directions for further research are also given

  12. 粒料桩复合地基承载力发挥值试验研究%Experimental Study on Efficiency Factor of Bearing Capacity of Granular Pile Composite Foundation

    Institute of Scientific and Technical Information of China (English)

    轩勇; 刘军勇

    2013-01-01

    结合实体公路工程,通过现场试验段土压力监测,计算复合地基承载力发挥值;结合破坏模式,对其复合地基承载力发挥值进行分析.研究结果表明:粒料桩复合地基按照土体先破坏计算的复合地基承载力发挥值,接近现场载荷试验结果,复合地基承载力可通过桩墩间土压力进行计算确定;不论是强夯置换砾石墩还是振动砾石桩,其破坏形式是桩(墩)间土先破坏引起的整个复合地基的破坏.%Combining with substantial highway engineering,efficiency factor of bearing capacity of composite foundation was calculated through soil pressure monitoring at the section for site test and,with failure mode,it was analyzed as well.The study result shows that for granular pile composite foundation,the efficiency factor of bearing capacity calculated in terms of earth mass failure taken place first is close to the result of on-site load test and the bearing capacity may be calculated through soil pressure between piles/piers.In addition,the failure mode is such that the whole composite foundation is destroyed in the event that the soil between piles (piers) is destructed at first,regardless of dynamic replacement gravel pier or vibration gravel pile.

  13. Behaviour of jacked and driven piles in sandy soil

    OpenAIRE

    Yang, J; Tham, LG; Lee, PKK; Chan, ST; Yu, F.

    2006-01-01

    As an alternative to conventional dynamic pile installation methods, pile jacking is an environmentally friendly technique that could become more widely accepted. Great concern has arisen over the performance of jacked piles as compared with that of driven piles. This paper describes a comprehensive field study that was aimed at investigating the differences and similarities between the behaviour of jacked H-piles and that of driven H-piles. The instrumented piles, varying in length from 32 t...

  14. Development of p-y Curves of Laterally Loaded Piles in Cohesionless Soil

    Directory of Open Access Journals (Sweden)

    Mahdy Khari

    2014-01-01

    Full Text Available The research on damages of structures that are supported by deep foundations has been quite intensive in the past decade. Kinematic interaction in soil-pile interaction is evaluated based on the p-y curve approach. Existing p-y curves have considered the effects of relative density on soil-pile interaction in sandy soil. The roughness influence of the surface wall pile on p-y curves has not been emphasized sufficiently. The presented study was performed to develop a series of p-y curves for single piles through comprehensive experimental investigations. Modification factors were studied, namely, the effects of relative density and roughness of the wall surface of pile. The model tests were subjected to lateral load in Johor Bahru sand. The new p-y curves were evaluated based on the experimental data and were compared to the existing p-y curves. The soil-pile reaction for various relative density (from 30% to 75% was increased in the range of 40–95% for a smooth pile at a small displacement and 90% at a large displacement. For rough pile, the ratio of dense to loose relative density soil-pile reaction was from 2.0 to 3.0 at a small to large displacement. Direct comparison of the developed p-y curve shows significant differences in the magnitude and shapes with the existing load-transfer curves. Good comparison with the experimental and design studies demonstrates the multidisciplinary applications of the present method.

  15. Experimental study on PHC piles of SP-SSA international container freight wharfs%SP-SSA国际集装箱码头PHC桩荷载试验研究

    Institute of Scientific and Technical Information of China (English)

    胡勇; 王建军

    2013-01-01

    This article took the SP-SSA international container freight wharfs as an example to testing the me-chanics,sedimentation and other properties of PHC piles by designed load testing program.The results showed that:The hammering force is approaching 6000kN when the piles length within the range of 0~25m ,and the maximum compressive stress and maximum compressive stress both within the length of 14~17m range when on dynamic load.When on static-load,the most powerful carrying capacity is approaching the loading position. When the load is 7000kN,the maximum settlement amounts of 1# pile and 2# pile are 27.48mm and 31.32mm.The analysis of force deformation characteristics under different types and sizes of loads will help us to find out the most unfavorable position of PHC pile ,and to provide technical support for engineering safety construction.%以越南巴地-头顿省SP-SSA国际集装箱码头为例,通过设计荷载试验方案对PHC桩的力学、沉降等性能进行测试。结果表明:动载时,0~25m范围内,锤击力接近6000kN,最大压、压应力均在约14-17m范围;静荷载时,接近加载部位发挥的承载能力强;7000kN时,1#、2#桩的最大沉降分别为27.48mm、31.32mm。分析桩体在不同类型和大小的荷载下的受力变形特性,得出桩体最不利部位,可为工程安全施工提供技术保障。

  16. Optimization Mathematical Model of Pile Forces for Offshore Piled Breasting Dolphins

    Institute of Scientific and Technical Information of China (English)

    周锡礽; 王东芹; 王晖; 朱福明

    2004-01-01

    An optimization mathematical model of the pile forces for piled breasting dolphins in the open sea under various loading conditions is presented. The optimum layout with the well distributed pile forces and the least number of piles is achieved by the multiplier penalty function method. Several engineering cases have been calculated and compared with the result of the conventional design method. It is shown that the number of piles can be reduced at least by 10% ~ 20%and the piles' bearing state is improved greatly.

  17. Static and dynamic pile testing of reinforced concrete piles with structure integrated fibre optic strain sensors

    Science.gov (United States)

    Schilder, Constanze; Kohlhoff, Harald; Hofmann, Detlef; Basedau, Frank; Habel, Wolfgang R.; Baeßler, Matthias; Niederleithinger, Ernst; Georgi, Steven; Herten, Markus

    2013-05-01

    Static and dynamic pile tests are carried out to determine the load bearing capacity and the quality of reinforced concrete piles. As part of a round robin test to evaluate dynamic load tests, structure integrated fibre optic strain sensors were used to receive more detailed information about the strains along the pile length compared to conventional measurements at the pile head. This paper shows the instrumentation of the pile with extrinsic Fabry-Perot interferometers sensors and fibre Bragg gratings sensors together with the results of the conducted static load test as well as the dynamic load tests and pile integrity tests.

  18. Experimental study of soil arching and transfer behavior of earth pressure about sheet-pile walls%桩板墙土拱效应及土压力传递特性试验研究

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    In order to further study the soil arching behind the sheet-pile wall and analyze the earth pressure load regulation and transmission characteristic, the field large-sized test and indoor model test are carried out by monitoring research. In addition, the test results can further reveal the regularities about soil arching and load distribution. Based on the comprehension of the action mechanism about the soil arching structure, the ratio between the earth pressure on the back side of pile and pressure on the breast board is regarded as a standard which is used to assess the arching. A test model box is designed and constructed in order to load behind sheet-pile wall at a rock slope. The earth pressure cells are fixed on the dorsal surfaces of sheet and piles to test the earth pressure during future 21 days. The test results show that the earth pressure ratio increases firstly and then tends to be stable as the development of time; therefore, the time effect is relatively obvious. In addition, multiple test conditions are also designed and done to make further analysis about the relationship between the soil arching and transfer behavior of earth pressure behind sheet-pile wall. The comparative researches are done about different baffle rigidities, pile spacings, filler properties and arrangement effects of sheets, which explains the transfer behavior of load behind sheet-pile wall in the passive soil pressure state.%  为更深入地研究桩板墙背侧的土拱效应,分析其土压力荷载的作用规律及传递特性,进一步揭示桩板墙土拱效应与荷载分配之间的联系,采用现场大型试验及室内模型试验开展相关的监测研究工作。基于对土拱结构承载机制的认识,将作用于桩背侧与桩间挡板中部土压力的比值作为衡量土拱效应作用效果的直观标准。在某一自然边坡上,设计施工桩板墙堆载试验的模型槽,在挡土板与抗滑桩背侧分别安装

  19. Literature review Quasi-static and Dynamic pile load tests: Primarily report on non-static pile load tests

    OpenAIRE

    Huy, N.Q.

    2010-01-01

    Pile testing, which plays an importance role in the field of deep foundation design, is performed by static and non-static methods to provide information about the following issues: (Poulos, 1998) - The ultimate capacity of a single pile. - The load-displacement behavior of a pile. - The performance of a pile during the test conditions. - The integrity of a pile (pile integrity test). For the purposes of verification the design axial capacity and the static load – settlement behavior of piles...

  20. 27 CFR 19.71 - Experimental or research operations by scientific institutions and colleges of learning.

    Science.gov (United States)

    2010-04-01

    ... Experimental or research operations by scientific institutions and colleges of learning. (a) General. The... scientific research to produce, receive, blend, treat, test, and store spirits, without payment of tax, for... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Experimental or...

  1. Evaluation of the Load-Displacement Relationships for Large-Diameter Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Brodbaek, K. T.; Moller, M.;

    2009-01-01

    was developed for slender piles with diameters much less than 6 m and it is based on a limited number of tests. The aim of the present work is to extend the p-y curve method to large-diameter non-slender piles by considering the effects of the pile diameter on the soil response. The main focus is the initial...... stiffness of the p-y curves. The evaluation is based on experimental work as well as three-dimensional numerical analyses in the commercial programme FLAC3D....

  2. Backfilling of a Scour Hole around a Pile in Waves and Current

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Petersen, Thor Ugelvig; Locatelli, Luca;

    2013-01-01

    This paper presents the results of an experimental investigation of the backfilling of scour holes around circular piles. Scour holes around a pile are generated either by a current or a wave. Subsequently, the flow climate is changed from current to wave, combined waves and current, or wave...... around the pile for the same wave (or combined waves and current) climate. The time scale of backfilling has been determined as a function of three parameters, namely, (1) the Keulegan-Carpenter number of the initial wave or current (which generates the initial scour hole); (2) that of the subsequent...

  3. Nonlinear Behavior of Single Piles in Jacket Type Offshore Platforms Using Incremental Dynamic Analysis

    Directory of Open Access Journals (Sweden)

    Mohammad A. Assareh

    2008-01-01

    Full Text Available The operation for offshore oil has become an important issue in the recent years. Offshore platforms are some of those structures which are built to withstand environmental and accidental loads during oil exploitation operation. One of the most usual types of these platforms is the Jacket Type Offshore Platform (JTOP which can be divided into three important parts, which are Deck, Jacket and piles. In order to increase the safety, particular attention should be paid to earthquake excitations which are directly applied to the piles of these structures. Nonlinearity in piles and buckling of the struts are important issues which have to be considered by the designers of offshore platforms. The case of nonlinearity in piles and failure capture in these members has not effectively been covered by researchers. Incremental Dynamic Analysis (IDA is a powerful tool to assess the capacity of a structure upon seismic loads. In this paper incremental dynamic analysis has been implemented on single piles considering soil-pile interactions and free field site response. The use of nonlinear materials and lateral load resisting elements in the incremental dynamic analysis done in this paper has made it possible to get promising insights for incorporation of appropriate limit states and applications of performance based engineering. Special Engineering Demand Parameters (EDP and Intensity Measures (IM have been introduced for the single pile dynamic analysis in jacket type offshore platforms.

  4. Thermal Conductivity Of Rubble Piles

    CERN Document Server

    Luan, Jing

    2015-01-01

    Rubble piles are a common feature of solar system bodies. They are composed of monolithic elements of ice or rock bound by gravity. Voids occupy a significant fraction of the volume of a rubble pile. They can exist up to pressure $P\\approx \\epsy\\mu$, where $\\epsy$ is the monolithic material's yield strain and $\\mu$ its rigidity. At low $P$, contacts between neighboring elements are confined to a small fraction of their surface areas. As a result, the effective thermal conductivity of a rubble pile, $\\kcon\\approx k(P/(\\epsy\\mu))^{1/2}$, can be orders of magnitude smaller than, $k$, the thermal conductivity of its monolithic elements. In a fluid-free environment, only radiation can transfer energy across voids. It contributes an additional component, $\\krad=16\\ell\\sigma T^3/3$, to the total effective conductivity, $\\keff=\\kcon +\\krad$. Here $\\ell$, the inverse of the opacity per unit volume, is of order the size of the elements and voids. An important distinction between $\\kcon$ and $\\krad$ is that the former i...

  5. 24 January 2012 - British Vice-Chancellor of the University of Cambridge Sir Leszek Borysiewicz signing the guest book with CERN Director-General, visiting ATLAS experimental area with Collaboration Deputy Spokesperson D. Charlton and Sm18 with engineer R. Veness.

    CERN Document Server

    Jean-Claude Gadmer

    2012-01-01

    24 January 2012 - British Vice-Chancellor of the University of Cambridge Sir Leszek Borysiewicz signing the guest book with CERN Director-General, visiting ATLAS experimental area with Collaboration Deputy Spokesperson D. Charlton and Sm18 with engineer R. Veness.

  6. 1 October 2013 - British Minister of State for Trade and Investment Lord Green of Hurstpierpoint signing the guest book with Head of Internationals Relations R. Voss; visiting the LHC tunnel at Point 1 and the ATLAS experimental cavern with ATLAS Collaboration Members K. Behr and J. Catmore.

    CERN Multimedia

    Jean-Claude Gadmer

    2013-01-01

    1 October 2013 - British Minister of State for Trade and Investment Lord Green of Hurstpierpoint signing the guest book with Head of Internationals Relations R. Voss; visiting the LHC tunnel at Point 1 and the ATLAS experimental cavern with ATLAS Collaboration Members K. Behr and J. Catmore.

  7. 17 January 2011 - British (Cambridge) Trustee of the London Science Museum Chair of the Management Committee of the Newton Institute for Mathematical Sciences H. Covington in the LHCB underground experimental area with A. Schopper; signing the guest book with Director for Accelerators and Technology S. Myers; throughout accompanied by R. Veness.

    CERN Multimedia

    Maximilien Brice

    2011-01-01

    17 January 2011 - British (Cambridge) Trustee of the London Science Museum Chair of the Management Committee of the Newton Institute for Mathematical Sciences H. Covington in the LHCB underground experimental area with A. Schopper; signing the guest book with Director for Accelerators and Technology S. Myers; throughout accompanied by R. Veness.

  8. 3 February 2011 - British Members of the Science and Technology Committee (Commons)led by A. Miller MP signing the guest book with CERN Director for Accelerators and Technology S. Myers; in the ATLAS experimental cavern at LHC Point 1 with Spokesperson F. Gianotti and Deputy D. Charlton.

    CERN Multimedia

    Maximilien Brice

    2011-01-01

    3 February 2011 - British Members of the Science and Technology Committee (Commons)led by A. Miller MP signing the guest book with CERN Director for Accelerators and Technology S. Myers; in the ATLAS experimental cavern at LHC Point 1 with Spokesperson F. Gianotti and Deputy D. Charlton.

  9. Test Setup for Axially Loaded Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    The test setup for testing axially static and cyclic loaded piles in sand is described in the following. The purpose for the tests is to examine the tensile capacity of axially loaded piles in dense fully saturated sand. The pile dimensions are chosen to resemble full scale dimension of piles used...... in offshore pile foundations today....

  10. Laboratory Model Test on Interaction of Pile-tip Soils and Pile-side Soils%灌注桩桩端与桩侧土体相互作用试验研究

    Institute of Scientific and Technical Information of China (English)

    王学知; 李亚东; 赵春风

    2012-01-01

    Based on the laboratory model experiment, according to the influence factors during the pile construction, the bearing condition of the pile-side soils and pile-tip soils is controlled by setting mire skin around the pile and asbestos at the bottom of pile. Then the influence regulation on the pile-tip bearing capacity and pile lateral friction is studied by the change of the condition of the pile-tip soils and pile-side soils respectively. By the experimental study, the commutative enhance mechanism is revealed.%基于室内模型桩试验方法,结合灌注桩施工工艺对桩侧与桩端土体造成的影响,通过在桩侧设置泥皮与在桩端铺设石棉毡的方法分别控制桩侧与桩端土体承载条件,考察桩侧土体性质变化对桩端阻力的影响规律以及桩端土体性质改变时桩侧摩阻力的变化特征,进而揭示灌注桩桩端与桩侧土体相互强化的规律.

  11. Airborne sound propagation over sea during offshore wind farm piling.

    Science.gov (United States)

    Van Renterghem, T; Botteldooren, D; Dekoninck, L

    2014-02-01

    Offshore piling for wind farm construction has attracted a lot of attention in recent years due to the extremely high noise emission levels associated with such operations. While underwater noise levels were shown to be harmful for the marine biology, the propagation of airborne piling noise over sea has not been studied in detail before. In this study, detailed numerical calculations have been performed with the Green's Function Parabolic Equation (GFPE) method to estimate noise levels up to a distance of 10 km. Measured noise emission levels during piling of pinpiles for a jacket-foundation wind turbine were assessed and used together with combinations of the sea surface state and idealized vertical sound speed profiles (downwind sound propagation). Effective impedances were found and used to represent non-flat sea surfaces at low-wind sea states 2, 3, and 4. Calculations show that scattering by a rough sea surface, which decreases sound pressure levels, exceeds refractive effects, which increase sound pressure levels under downwind conditions. This suggests that the presence of wind, even when blowing downwind to potential receivers, is beneficial to increase the attenuation of piling sound over the sea. A fully flat sea surface therefore represents a worst-case scenario. PMID:25234870

  12. Pegase: safety studies - experimental study of burn-out risks in transient operation

    International Nuclear Information System (INIS)

    An experiment out-of-pile experimental set up is proposed simulating the breakage of a pipe supplying the core of the reactor Pegase. The two fast phenomena, depressurization of the vessel and flow reversal, are reproduced. The aluminium heating channel has the same shape as that of the reactor channel but has twice the heat capacity. The starting conditions are V= 4.50 and 6 m/sec., TE = 50 and 60 degrees C and PE = 4 bars. The results show that the critical flux PHIC varies with the flow-rate from 45 to 60 W/cm2 in the case where there is no power reduction. For fluxes of 90 W/cm2 the results lead to the conclusion that the hot channel attains a state of burn-out after 0.1 sec. and that its temperature reaches 500 C in 0.8 sec. The hydrodynamic conditions in the channels after the accident involve periodic expulsion (0.2 to 0.5 sec.), characteristic of boiling at low pressure. A study of the steady state flow redistribution through a by-pass has given flux redistribution PHIR of 190 W/cm2 for a flow rate of 4.5 m/sec. at 50 and of 175 W/cm2 at 60 C. These values increase which has to be made between the critical flux PHIC during the periodic expulsion conditions and the flux redistribution PHIR during the steady state, has been shown. (author)

  13. Experimental study on enhancing bearing capacity of marine soft soil foundation with cement-mixing piles%水泥土搅拌桩增强海相软土地基承载力的试验研究

    Institute of Scientific and Technical Information of China (English)

    吕田丰

    2015-01-01

    为了研究本地区海相软土地基采用水泥土搅拌桩进行加固技术,提高海相软土地基承载力的可行性。选取了本地区典型的海相软土场地,采用水泥土搅拌桩对软土地基进行加固,利用浅层平板载荷试验和复合地基载荷试验的方法,对海相软土加固前后的地基承载能力进行了比较分析。结果表明,利用水泥土搅拌桩对海相软土地基进行加固,可以有效地增强海相软土地基承载力。%In order to study the feasibility of improving bearing capacity of marine soft soil foundation through the technique of reinforcing local marine soft soil foundation with cement-mixing piles,we select typical marine soft soil site and reinforce the soft soil foundation with cement-mixing piles.Through super-ficial plate loading test and composite foundation loading test,we conduct comparative analysis on the bear-ing capacities of marine soft soil foundation before and after the reinforcement.Results show that reinfor-cing marine soft soil foundation with cement-mixing piles can improve the bearing capacity effectively.

  14. Pile Model Tests Using Strain Gauge Technology

    Science.gov (United States)

    Krasiński, Adam; Kusio, Tomasz

    2015-09-01

    Ordinary pile bearing capacity tests are usually carried out to determine the relationship between load and displacement of pile head. The measurement system required in such tests consists of force transducer and three or four displacement gauges. The whole system is installed at the pile head above the ground level. This approach, however, does not give us complete information about the pile-soil interaction. We can only determine the total bearing capacity of the pile, without the knowledge of its distribution into the shaft and base resistances. Much more information can be obtained by carrying out a test of instrumented pile equipped with a system for measuring the distribution of axial force along its core. In the case of pile model tests the use of such measurement is difficult due to small scale of the model. To find a suitable solution for axial force measurement, which could be applied to small scale model piles, we had to take into account the following requirements: - a linear and stable relationship between measured and physical values, - the force measurement accuracy of about 0.1 kN, - the range of measured forces up to 30 kN, - resistance of measuring gauges against aggressive counteraction of concrete mortar and against moisture, - insensitivity to pile bending, - economical factor. These requirements can be fulfilled by strain gauge sensors if an appropriate methodology is used for test preparation (Hoffmann [1]). In this paper, we focus on some aspects of the application of strain gauge sensors for model pile tests. The efficiency of the method is proved on the examples of static load tests carried out on SDP model piles acting as single piles and in a group.

  15. Numerical Modeling of Laterally Loaded Piles

    OpenAIRE

    S. T. Kok; B. B.k. Huat

    2008-01-01

    Design of laterally loaded piles due to soil movement relies on a number of theoretical and numerical approaches. However, the magnitude of soil movement is difficult to estimate with reasonable confidence and accuracy. Finite Element Analysis (FEA) offers an excellent alternative to study pile-soil interaction and piles response under lateral loading due to soil movement. This research presents published analytical results and case history modeled in a 2D finite element environment in the ca...

  16. Pile Spacing Optimization of Short Piled Raft Foundation System for Obtaining Minimum Settlement on Peat

    Science.gov (United States)

    Suro, S. M.; Bakar, I.; Sulaeman, A.

    2016-07-01

    Short Piled Raft is a modified piled raft foundation system, which represents combination between raft foundation and pile foundation, but the length of pile is relatively shorter. The basic concept of the Short Piled Raft foundation system considers the passive soil pressure creating a stiff condition of slab-pile system. This means that the thin concrete slab floats on the supporting soil, while the piles serve as stiffeners concrete slab and also to reduce settlement of the foundation. Slab to pile ratio of such system has been mentioned by several researchers, however the optimum pile spacing of stability performance for obtaining minimum settlement on peat haven't been clearly discussed. In this study, finite element method to simulate the stability performance related to settlement of Short Piled Raft foundation system was used. Short Piled Raft foundation system with concrete slab of 7.0 m x 7.0 m square was assumed to be built on peat with the thickness of 3.5 m. The material properties of pile and raft were constant. The outer diameter of galvanized steel pipe as pile was 0.30 m; raft thickness was considered to be constant of 0.15 m and the length of pile was 3.0 m, while the pile spacing varied from 0.50 to 3.00 m. Point load varied from 0 to 100 kN with increment of 20 kN was also considered as a static load, acted on the centre of the concrete slab. Optimization was done by comparing each numerical result of simulations, thus conclusion can easily be drawn. The optimum pile spacing was 1.00 m which produced minimum settlement of 30.11 mm under the load of 100 kN.

  17. 搅拌桩联合塑料排水板地基加固现场试验研究%In- site Experimental Study on Behavior of Foundation Reinforcement of Cement Deep Mixing Pile with Plastic Drainage Board

    Institute of Scientific and Technical Information of China (English)

    丁光文

    2011-01-01

    获得组合措施处理深厚层软土的作用机理、沉降、桩一土荷载分担等特性,为确定设计计算方法提供依据.研究结论:在搅拌桩复合地基中加入较长的塑料排水板后:(1)可以起到加快深厚软土层排水固结的作用,从而加快地基土沉降完成速度,减小工后沉降;(2)加快侧向位移的发展,且其发展与排水条件密切相关;(3)地基土强度提高较快,桩土应力比明显小于搅拌桩复合地基,表明其地基更有利于地基土承载作用的发挥.%Research purposes: The purpose is to obtain characteristics of the action mechanism, the settlement and the load bearing of the pile - soil when reinforcing the deep buried soft soil by taking the comprehensive measures for providing the basis for determining the design calculation method.Research conclusions: After inserting the plastic drainage board in the composite foundation of the cement deep mixing pile,the effects of the drainage and consolidation in the deep buried soft soil can be speeded up to speed up the completion of the foundation settlement to reduce the post - construction settlement, the displacement development in the side direction can be speeded up and it is closely related to the drainage condition, and the improvement of the strength of the foundation soil can be speeded up and the stress ratio of the pile - soil is obviously smaller than the composite foundation of cement deep mixing pile and it favors for giving the play the load bearing capacity of the foundation soil.

  18. Point resistance of piles in sand

    OpenAIRE

    Miura, Norihiko

    1983-01-01

    Mechanism of point resistance of pile in sand was investigated mainly from the viewpoint of the particle-crushing of sand at the pile tip. It is shown that the work dissipated in the particle-crushing of sand is as large as 66 percent of the total work done by the external force, hence the point resistance of a pile in sand greatly depends on the particle-crushing property of the sand. It is also shown that the relationship between point resistance and vertical pressure of a pile can be predi...

  19. Regressive approach for predicting bearing capacity of bored piles from cone penetration test data

    Directory of Open Access Journals (Sweden)

    Iyad S. Alkroosh

    2015-10-01

    Full Text Available In this study, the least square support vector machine (LSSVM algorithm was applied to predicting the bearing capacity of bored piles embedded in sand and mixed soils. Pile geometry and cone penetration test (CPT results were used as input variables for prediction of pile bearing capacity. The data used were collected from the existing literature and consisted of 50 case records. The application of LSSVM was carried out by dividing the data into three sets: a training set for learning the problem and obtaining a relationship between input variables and pile bearing capacity, and testing and validation sets for evaluation of the predictive and generalization ability of the obtained relationship. The predictions of pile bearing capacity by LSSVM were evaluated by comparing with experimental data and with those by traditional CPT-based methods and the gene expression programming (GEP model. It was found that the LSSVM performs well with coefficient of determination, mean, and standard deviation equivalent to 0.99, 1.03, and 0.08, respectively, for the testing set, and 1, 1.04, and 0.11, respectively, for the validation set. The low values of the calculated mean squared error and mean absolute error indicated that the LSSVM was accurate in predicting the pile bearing capacity. The results of comparison also showed that the proposed algorithm predicted the pile bearing capacity more accurately than the traditional methods including the GEP model.

  20. Simulating pile load-settlement behavior from CPT data using intelligent computing

    Science.gov (United States)

    Alkroosh, I.; Nikraz, H.

    2011-09-01

    Analysis of pile load-settlement behavior is a complex problem due to the participation of many factors involved. This paper presents a new procedure based on artificial neural networks (ANNs) for simulating the load-settlement behavior of pile foundations embedded in sand and mixed soils (subjected to axial loads). Three ANN models have been developed, a model for bored piles and two other models for driven piles (a model for each of concrete and steel piles). The data used for development of the ANN models is collected from the literature and comprise a series of in-situ piles load tests as well as cone penetration test (CPT) results. The data of each model is divided into two subsets: Training set for model calibration and independent validation set for model verification. Predictions from the ANN models are compared with the results of experimental data and with predictions of number of currently adopted load-transfer methods. Statistical analysis is used to verify the performance of the models. The results indicate that the ANN model performs very well and able to predict the pile load-settlement behaviour accurately.

  1. Influence of reaction piles on test pile response in a static load test

    Institute of Scientific and Technical Information of China (English)

    Qian-qing ZHANG; Shu-cai LI; Zhong-miao ZHANG

    2013-01-01

    This work presents a new analytical method to analyze the influence of reaction piles on the test pile response in a static load test.In our method,the interactive effect between soil and pile is simulated using independent springs and the shear displacement method is adopted to analyze the influence of reaction piles on test pile response.Moreover,the influence of the sheltering effect between reaction piles and test pile on the test pile response is taken into account.Two cases are analyzed to verify the rationality and efficiency of the present method.This method can be easily extended to a nonlinear response of an influenced test pile embedded in a multilayered soil,and the validity is also demonstrated using centrifuge model tests and a computer program presented in the literature.The present analyses indicate that the proposed method will lead to an underestimation of the test pile settlement in a static load test if the influence of the presence of reaction piles on the test pile response is neglected.

  2. 6 June 2012 - British Member of Parliament for Bromsgrove Parliamentary Private Secretary to George Osborne, Chancellor of the Exchequer S. Javid MP signing the guest book with Adviser E. Tsesmelis and visiting the LHC superconducting magnet test hall with Beams Department Head P. Collier, Head of Operations M. Lamont and Adviser E. Tsesmelis.

    CERN Multimedia

    Maximilien Brice

    2012-01-01

    6 June 2012 - British Member of Parliament for Bromsgrove Parliamentary Private Secretary to George Osborne, Chancellor of the Exchequer S. Javid MP signing the guest book with Adviser E. Tsesmelis and visiting the LHC superconducting magnet test hall with Beams Department Head P. Collier, Head of Operations M. Lamont and Adviser E. Tsesmelis.

  3. Chronocentrism and British criminology.

    Science.gov (United States)

    Rock, Paul

    2005-09-01

    Criminologists display a largely unexamined propensity to ignore writings that are more than fifteen or so years old, with evident consequences for the public presentation and validation of expert knowledge. A citation study was combined with detailed observations from British criminologists to ascertain quite how that disavowal of the past was accomplished.

  4. Prevent and "British Values"

    Science.gov (United States)

    Kenny, Alex; Ghale, Baljeet

    2015-01-01

    At the recent National Union of Teachers' conference the role of the Prevent strategy and the introduction of "British Values" in the Office for Standards in Education, Children's Services and Skills framework emerged as key issues for delegates. Two of the speeches made at the conference are presented here.

  5. 1927: a British eclipse

    Science.gov (United States)

    Marriott, R. A.

    1999-06-01

    The total solar eclipse of 1927 June 29 was the first to be seen over the British mainland for 203 years. It caused nationwide excitement, induced mass population movement to the towns, villages, moorlands and offshore waters of Wales and the north of England, and severely tested the country's transport and communication systems.

  6. Analysis of Sandia in-pile EOS experiments

    International Nuclear Information System (INIS)

    Preliminary analysis has been carried out of the dynamic in-pile equation-of-state measurements for UO2, conducted at Sandia Laboratories, aimed at reducing the uncertainties in the effective UO2 enthalpy corresponding to the measured pressures. Of the remaining width of the p-H band of some 350 J/g, about 200 J/g originate in the uncertainties of the analytical modelling and about 150 J/g result from the scatter in the experimental data

  7. Refreezing of cast-in-place piles under various engineering conditions

    Institute of Scientific and Technical Information of China (English)

    Lei Guo; QiHao Yu; XiaoNing Li; XinBin Wang; YongYu Yue

    2015-01-01

    In the construction of the Qinghai-Tibet Power Transmission Line (QTPTL), cast-in-place piles (CIPPs) are widely applied in areas with unfavorable geological conditions. The thermal regime around piles in permafrost regions greatly affects the stability of the towers as well as the operation of the QTPTL. The casting of piles will markedly affect the thermal regime of the surrounding permafrost because of the casting temperature and the hydration heat of cement. Based on the typical geological and engineering conditions along the QTPTL, thermal disturbance of a CIPP to surrounding permafrost under different casting seasons, pile depths, and casting temperatures were simulated. The results show that the casting season (summer versus winter) can influence the refreezing process of CIPPs, within the first 6 m of pile depth. Sixty days after being cast, CIPPs greater than 6 m in depth can be frozen regardless of which season they were cast, and the foundation could be refrozen after a cold season. Comparing the refreezing characteristics of CIPPs cast in different seasons also showed that, without considering the ground surface conditions, warm seasons are more suitable for casting piles. With the increase of pile depth, the thermal effect of a CIPP on the surrounding soil mainly expands vertically, while the lateral heat disturbance changes little. Deeper, longer CIPPs have better stability. The casting temperature clearly affects the thermal disturbance, and the radius of the melting circle increases with rising casting temperature. The optimal casting temperature is between 2 °C and 9 °C.

  8. Regional scale selenium loading associated with surface coal mining, Elk Valley, British Columbia, Canada.

    Science.gov (United States)

    Wellen, Christopher C; Shatilla, Nadine J; Carey, Sean K

    2015-11-01

    Selenium (Se) concentrations in surface water downstream of surface mining operations have been reported at levels in excess of water quality guidelines for the protection of wildlife. Previous research in surface mining environments has focused on downstream water quality impacts, yet little is known about the fundamental controls on Se loading. This study investigated the relationship between mining practices, stream flows and Se concentrations using a SPAtially Referenced Regression On Watershed attributes (SPARROW) model. This work is part of a R&D program examining the influence of surface coal mining on hydrological and water quality responses in the Elk Valley, British Columbia, Canada, aimed at informing effective management responses. Results indicate that waste rock volume, a product of mining activity, accounted for roughly 80% of the Se load from the Elk Valley, while background sources accounted for roughly 13%. Wet years were characterized by more than twice the Se load of dry years. A number of variables regarding placement of waste rock within the catchments, length of buried streams, and the construction of rock drains did not significantly influence the Se load. The age of the waste rock, the proportion of waste rock surface reclaimed, and the ratio of waste rock pile side area to top area all varied inversely with the Se load from watersheds containing waste rock. These results suggest operational practices that are likely to reduce the release of Se to surface waters.

  9. Regional scale selenium loading associated with surface coal mining, Elk Valley, British Columbia, Canada.

    Science.gov (United States)

    Wellen, Christopher C; Shatilla, Nadine J; Carey, Sean K

    2015-11-01

    Selenium (Se) concentrations in surface water downstream of surface mining operations have been reported at levels in excess of water quality guidelines for the protection of wildlife. Previous research in surface mining environments has focused on downstream water quality impacts, yet little is known about the fundamental controls on Se loading. This study investigated the relationship between mining practices, stream flows and Se concentrations using a SPAtially Referenced Regression On Watershed attributes (SPARROW) model. This work is part of a R&D program examining the influence of surface coal mining on hydrological and water quality responses in the Elk Valley, British Columbia, Canada, aimed at informing effective management responses. Results indicate that waste rock volume, a product of mining activity, accounted for roughly 80% of the Se load from the Elk Valley, while background sources accounted for roughly 13%. Wet years were characterized by more than twice the Se load of dry years. A number of variables regarding placement of waste rock within the catchments, length of buried streams, and the construction of rock drains did not significantly influence the Se load. The age of the waste rock, the proportion of waste rock surface reclaimed, and the ratio of waste rock pile side area to top area all varied inversely with the Se load from watersheds containing waste rock. These results suggest operational practices that are likely to reduce the release of Se to surface waters. PMID:26136156

  10. Attempt of automated space network operations at ETS-VI experimental data relay system

    Science.gov (United States)

    Ishihara, Kiyoomi; Sugawara, Masayuki

    1994-01-01

    National Space Development Agency of Japan (NASDA) is to perform experimental operations to acquire necessary technology for the future inter-satellite communications configured with a data relay satellite. This paper intends to overview functions of the experimental ground system which NASDA has developed for the Engineering Test Satellite VI (ETS-VI) Data Relay and Tracking Experiment, and to introduce Space Network System Operations Procedure (SNSOP) method with an example of Ka-band Single Access (KSA) acquisition sequence. To reduce operational load, SNSOP is developed with the concept of automated control and monitor of both ground terminal and data relay satellite. To perform acquisition and tracking operations fluently, the information exchange with user spacecraft controllers is automated by SNSOP functions.

  11. THE RELATIONSHIP BETWEEN BRITISH WAR CORRESPONDENTS IN THE FIELD AND BRITISH MILITARY INTELLIGENCE DURING THE ANGLO-BOER WAR

    Directory of Open Access Journals (Sweden)

    Donal P McCrachen

    2015-05-01

    Full Text Available This article chronicles the developing relationship between the press corps on the British side and British Military Intelligence during the Anglo-Boer War, particularly during the formal and non-guerrilla phase of the conflict. The article comments on the nature and composition of both the press corps and of the military intelligence operation. In particular, the article looks at the problem issues relating to the relationship: licensing correspondents, censorship, monitoring journalists’ activities, as well as the successful attempt of the intelligence sector to bring the press into their campaign to spread pro-British propaganda. The role of the press in the saga of the attempt to make British Military Intelligence a scapegoat for British initial failures is also mentioned.

  12. Effect of pile-cap connection on behavior of torsionally loaded pile groups

    Institute of Scientific and Technical Information of China (English)

    Ling-gang KONG; Li-min ZHANG

    2008-01-01

    To evaluate the respouses of fixed and pinned pile groups under torsiun, a method is presented to analyze the nonlinear behavior of free-standing pile groups with rigid pile caps. The method is capable of simulating the nonlinear soil response in the near field usingp-y and τ-θ curves, the far-field interactions through Mindlin's and Randolph's elastic solutions, and the coupling effect of lateral resistance on torsional resistance of the individual piles using an empirical factor. Based on comparisons of the solutions for fixedand pinned-head, 1×2, 2×2, and 3×3 pile groups subjected to torsion, it was found that pile-cap connection significantly influences the torsional capacity of pile groups and the assignment of applied torques in the pile groups. In this study, the applied torques for the pinned-head pile groups are only 44%~64% of those for the corresponding fixed-head pile groups at a twist angle of 2°. Such a difference is mainly due to the change of the lateral resistances of individual piles in the groups.

  13. Operational experience with synchrotron light interferometers for CEBAF experimental beam lines

    Energy Technology Data Exchange (ETDEWEB)

    Pavel Chevtsov

    2006-10-24

    Beam size and energy spread monitoring systems based on Synchrotron Light Interferometers (SLI) have been in operations at Jefferson Lab for several years. A non-invasive nature and a very high (a few mm) resolution of SLI make these instruments valuable beam diagnostic tools for the CEBAF accelerator. This presentation describes the evolution of the Synchrotron Light Interferometer at Jefferson Lab and highlights our extensive experience in the installation and operation of the SLI for CEBAF experimental beam lines.

  14. Steel Sheet Pile Walls in Soft Soil

    NARCIS (Netherlands)

    Kort, D.A.

    2002-01-01

    For almost a century, steel sheet pile walls are applied worldwide as earth retaining structures for excavations and quay walls. Within the framework of the development of European structural codes for Civil Engineering works, the Eurocodes, Eurocode 3 Part 5 for design of steel sheet pile walls was

  15. Tension Tests On Bored Piles In Sand

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Clausen, Johan; Damkilde, Lars

    2006-01-01

    The lengths of the bored piles varied from 2 m to 6 m and all were of a diameter of 140 mm. The piles were tested to failure in tension and the load-displacement relations were recorded. The investigation has shown pronounced differences between the load bearing capacities obtained by different...

  16. Analysis of pile load-transfer under pile-side softening

    Institute of Scientific and Technical Information of China (English)

    刘杰; 张可能

    2003-01-01

    A set of analytical equations for the variation of the axial force along depth and the pile-top load-settle-ment curve were established, using tri-linear softening model to pile-side soil and bilinear hardening model to pile-end soil . Influences of the pile-side and pile-end soil behavior on the load-settlement curve were discussed, indica-ting that the lowering reason for the variation step degree of the axial force along depth is the softening of the pile-side soil to result in the side friction lowering when the pile-top load is increased. To verify the reliability of thismethod, the parameters used in calculation are obtained from the test in Zhuzhou area. The obtained results are thencompared with the tested results. Contrast shows that the calculated results and the tested values are very close,which illustrates that the proposed method is reliable.

  17. Experimental study on corrosion prevention of concrete pile foundation of a large power plant in Shandong%山东某大型电厂桩基混凝土防腐蚀性试验

    Institute of Scientific and Technical Information of China (English)

    李吉林

    2013-01-01

    为研究桩基混凝土在腐蚀性地下水环境中的耐久性,依据山东某大型电厂中等~强腐蚀性地下水地质条件,在Cl-与SO2-4共存的地下水环境与只存在SO2-4的水环境中进行桩基混凝土防腐蚀性试验。结果表明:在Cl-与SO2-4共存的地下水环境中,混凝土受硫酸盐侵蚀的程度比只存在SO2-4的水环境中轻微;掺加防腐剂并没有明显提高混凝土抗蚀能力;抗硫酸盐水泥的抗硫酸盐侵蚀性与普通硅酸盐水泥接近,但抗氯离子侵入性难以满足耐久性要求;采用普通硅酸盐水泥、大掺量掺和料、低水胶比的高性能混凝土能满足桩基耐久性要求。%In order to study the durability of concrete piles in a corrosive groundwater environment, concrete corrosion resistant test of pile foundation in the environments with Cl- and SO2-4 coexistance and with only SO2-4 existance was performed, according to medium-highy corrosive groundwater geological conditions of a large power plant in Shandong. The results show that in the Cl-and SO2-4 coexistence groundwater environment, sulfate attack concrete situation is slightly lower than in the presence of SO2-4 only environment, the conventional doped preservatives does not significantly increase corrosion resistance, and resistance to sulfur cement and sulphate resistance of ordinary Portland cement remain close, but resistance to chloride ion invasive can not meet durability requirements. Finally, the ordinary Portland cement and admixture with low water-cement ratio, high-performance concrete pile can be used to meet durability requirements.

  18. Study and modelling of the in-pile densification of the UO{sub 2} and MO{sub x} nuclear oxides; Etude et modelisation de la densification en pile des oxydes nucleaires UO{sub 2} et MO{sub x}

    Energy Technology Data Exchange (ETDEWEB)

    Boulore, A

    2001-03-01

    Amongst the many phenomena which take place in the course of the irradiation of UO{sub 2} or (U, Pu)O{sub 2} nuclear fuels, one of them involves the elimination of a fraction of the as-fabricated porosity. In-pile densification or sintering can reach 2.5%, i.e. approximately half the initial volume of pores is likely to disappear. Our literature survey indicates that the amplitude and kinetics of the phenomenon are both heavily dependent on the initial fuel microstructure. Micro-structural characterisation techniques of oxide fuels have therefore been developed in conjunction with quantitative image analysis methods. The ensuing methodology enables a quantitative comparison of micro-structural features in different fuels and has been applied to ascertaining the influence of the local fission rate and temperature on in-pile densification. It is thus revealed that in-pile operation eliminates a significant fraction of pores smaller than 3 microns in diameter. The experimental data generated has been used to set up a semi-empirical and a mechanistic model. The former is based on experimental results and is not essentially predictive. The inability of this model to predict the in-pile densification of oxide fuels is illustrated by the fact that the maximum fraction of pores that disappears is proportional to an empirical function of fission rate, and temperature. The proportionality factor appears to be difficult to correlate quantitatively to any given micro-structural feature. The model has however been applied to the interpretation of an in-pile densification experiment carried out in the Halden reactor (Norway). The latter model is mechanistic, i.e. it is based on the solution to a set of equations that describe the coupled temperature and radiation induced phenomena which occur in-pile. These can broadly be broken down into three categories: the fission fragment-pore interaction, the creation of point defects as the fission fragments slow down, and the diffusion

  19. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting.

    Science.gov (United States)

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-04-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems. PMID:26949962

  20. Model Tests of Pile Defect Detection

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The pile, as an important foundation style, is being used in engineering practice. Defects of different types and damages of different degrees easily occur during the process of pile construction. So,dietecting defects of the pile is very important. As so far, there are some difficult problems in pile defect detection. Based on stress wave theory, some of these typical difficult problems were studied through model tests. The analyses of the test results are carried out and some significant results of the low-strain method are obtained, when a pile has a gradually-decreasing crosssection part, the amplitude of the reflective signal originating from the defect is dependent on the decreasing value of the rate of crosssection β. No apparent signal reflected from the necking appeares on the velocity response curve when the value of β is less than about 3.5 %.

  1. American and British English

    Institute of Scientific and Technical Information of China (English)

    袁波

    2004-01-01

    @@ The difficulty for the nonnative learner of English is there is no standard English form. He is confronted(面对) with two English dialects (方言) to learn: British English and American English (leaving aside Australian,Indian, South African English ete.) And despite the many cross-cultural influences, it seems that the vocabularies, spellings and pronunciations of these two dialects are diverging year by year.

  2. EXPERIMENTAL STUDY OF EFFECTS OF OPERATING CONDITIONS ON THE FLOW CHARACTERISTICS OF WATER HYDRAULIC THROTTLE

    Institute of Scientific and Technical Information of China (English)

    Liu Yinshui; Nie Songlin; Zhu Yuquan; He Xiaofeng; Li Zhuangyun

    2004-01-01

    Experimental investigations are made on the effects of operating conditions on the flow characteristics of throttle when tap water is used as the working media. The researched throttles include cone poppet valve, ball valve, disc valve and dumping orifice. Operating condition includes poppet lift, working media, back pressure, medium temperature, etc. Because the vapourous pressure of water is much higher than that of oil, cavitation is easier to occur in water hydraulic elements and systems, so the effects of operating conditions on the cavitation characteristics of throttle are also researched.

  3. Operational readiness review for the Waste Experimental Reduction Facility. Final report

    International Nuclear Information System (INIS)

    An Operational Readiness Review (ORR) at the Idaho National Engineering Laboratory's (INEL's) Waste Experimental Reduction Facility (WERF) was conducted by EG ampersand G Idaho, Inc., to verify the readiness of WERF to resume operations following a shutdown and modification period of more than two years. It is the conclusion of the ORR Team that, pending satisfactory resolution of all pre-startup findings, WERF has achieved readiness to resume unrestricted operations within the approved safety basis. ORR appraisal forms are included in this report

  4. Operational readiness review for the Waste Experimental Reduction Facility. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    An Operational Readiness Review (ORR) at the Idaho National Engineering Laboratory`s (INEL`s) Waste Experimental Reduction Facility (WERF) was conducted by EG&G Idaho, Inc., to verify the readiness of WERF to resume operations following a shutdown and modification period of more than two years. It is the conclusion of the ORR Team that, pending satisfactory resolution of all pre-startup findings, WERF has achieved readiness to resume unrestricted operations within the approved safety basis. ORR appraisal forms are included in this report.

  5. Experimental study on dielectric barrier discharge actuators operating in pulse mode

    NARCIS (Netherlands)

    Kotsonis, M.; Veldhuis, L.

    2010-01-01

    An experimental investigation is performed on the operation of dielectric barrier discharge plasma actuators used as manipulators of secondary and unsteady flow structures such as boundary layer instabilities or shedding vortices. The actuators are tested mainly in pulse mode. High sample rate hot-w

  6. 3D finite element analysis on pile-soil interaction of passive pile group

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ming-hua; LIU Dun-ping; ZHANG Ling; JIANG Chong

    2008-01-01

    The interaction between pile and soft soil of the passive pile group subjected to soil movement was analyzed with three-dimensional finite element model by using ANSYS software. The soil was assumed to be elastic-plastic complying with the Drucker-Prager yield criterion in the analysis. The large displacement of soil was considered and contact elements were used to evaluate the interaction between pile and soil. The influences of soil depth of layer and number of piles on the lateral pressure of the pile were investigated, and the lateral pressure distributions on the (2×1) pile group and on the (2×2) pile group were compared. The results show that the adjacent surcharge may result in significant lateral movement of the soft soil and cousiderable pressure on the pile. The pressure acting on the row near the surcharge is higher than that on the other row, due to the "barrier" and arching effects in pile groups. The passive load and its distribution should be taken into account in the design of the passive piles.

  7. Vertical vibration of a large diameter pipe pile considering transverse inertia effect of pile

    Institute of Scientific and Technical Information of China (English)

    郑长杰; 刘汉龙; 丁选明; 周航

    2016-01-01

    Considering the transverse inertia effect of pile, the vertical dynamic response of a large diameter pipe pile in viscoelastic soil layer is studied. The wave propagations in the outer and inner soil are simulated by three-dimensional elastodynamic theory and those in the pile are simulated by Rayleigh-Love rod theory. The vertical and radial displacements of the outer and inner soil are obtained by utilizing Laplace transform technique and differentiation on the governing equations of soils. Then, based on the continuous conditions between the pile and soils, the displacements of the pile are derived. The frequency domain velocity admittance and time domain velocity response of the pile top are also presented. The solution is compared to a classical rod model solution to verify the validity. The influences of the radii and Poisson ratio of pile on the transverse inertia effect of pile are analyzed. The parametric study shows that Poisson ratio and outer radius of pile have significant influence on the transverse inertia effect of large diameter pipe piles, while the inner radius has little effect.

  8. Analysis of effect of different construction methods of piles on the end effect on skin friction of piles

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hongbo; CHEN Zhuchang

    2007-01-01

    Based on the comparative analysis of end effect on skin friction of displacement-pile (driven pile),the end effect on skin friction of bored pile is studied.The end effect on skin friction between driven pile and bored pile is different and the end effect on skin friction of bored pile is reduce of skin friction in the soil layer adjacent to the pile end.The degradation degree of skin friction is deduced with the increase of the distance from pile end.The concept of additional mud cake formed by the effect of cushion at the bottom of borehole during pouring concrete is introduced to explain the mechanism of end effect on skin friction of the bored pile.The test results of post-grouting piles indicate that the post-grouting technique is an effective way to improve the end effect on skin friction of bored pile.

  9. Centrifuge model test on dynamic behavior of group-pile foundation With inclined piles and its numerical simulation

    Institute of Scientific and Technical Information of China (English)

    Feng ZHANG; Katsunori OKAWA; Makoto KIMURA

    2008-01-01

    In this paper, dynamic behavior of a grouppile foundation with inclined piles in loose sand has been investigated with centrifuge model tests. The test results are also simulated with elastoplastic dynamic finite ele-ment method, in which, not only sectional force of piles, stress of ground, but also deformation of piles are calcu-lated using a three-dimensional elastoplastic dynamic finite element analysis (Code name: DGPILE-3D). The numerical analyses are conducted with a full system in which a superstructure, a pile foundation and surround-ing ground are considered together so that interaction between pile foundation and soils can be properly simu-lated because the nonlinearities of both the pile and the ground are described with suitable constitutive models. Different types of piles, vertical pile or inclined pile, are considered in order to verify the different characteristics of a group pile foundation with inclined piles. The validity of the calculation is verified by the model tests.

  10. 40 CFR 265.254 - Design and operating requirements.

    Science.gov (United States)

    2010-07-01

    ... DISPOSAL FACILITIES Waste Piles § 265.254 Design and operating requirements. The owner or operator of each... waste pile unit on which construction commences after July 29, 1992, and each such replacement of an existing waste pile unit that is to commence reuse after July 29, 1992 must install two or more liners...

  11. Avoidance of Pile-Driving Noise by Hudson River Sturgeon During Construction of the New NY Bridge at Tappan Zee.

    Science.gov (United States)

    Krebs, Justin; Jacobs, Fred; Popper, Arthur N

    2016-01-01

    Sturgeon movements were monitored during a pile-driving operation. Fewer sturgeon were detected during pile driving and remained for a shorter time than during silent control periods. Moreover, the short time spent by sturgeon near pile driving suggests that they were unlikely to have reached the criterion of 187 dB re 1 μPa(2)·s cumulative sound exposure level. These results suggest that sturgeon are likely to avoid impact pile driving and not remain long enough to experience physiological effects, thus providing empirical evidence that the 206 dB re 1 μPa peak sound pressure level is the appropriate criterion for assessing the impacts of pile-driving noise on sturgeon.

  12. Operation and management manual of JT-60 experimental data analysis system

    International Nuclear Information System (INIS)

    In the Japan Atomic Energy Agency Naka Fusion Institute, a lot of experiments have been conducted by using the large tokamak device JT-60 aiming to realize fusion power plant. In order to optimize the JT-60 experiment and to investigate complex characteristics of plasma, JT-60 experimental data analysis system was developed and used for collecting, referring and analyzing the JT-60 experimental data. Main components of the system are a data analysis server and a database server for the analyses and accumulation of the experimental data respectively. Other peripheral devices of the system are magnetic disk units, NAS (Network Attached Storage) device, and a backup tape drive. This is an operation and management manual the JT-60 experimental data analysis system. (author)

  13. Vibration and Long-Term Performance Analysis of Pile-Plank-Supported Low Subgrade of Ballastless Track under Excitation Loads

    Directory of Open Access Journals (Sweden)

    Junjie Huang

    2015-01-01

    Full Text Available Pile-plank structures are widely applied for high-speed railway built in soft ground in China. It can be used as a reinforcement to improve the behavior of subgrade by providing vertical confinement to increase their stiffness and strength and reduce the subgrade settlement of ballastless track. However, the use of pile-board structure for soft ground reinforcement of high-speed railway is hindered by the existing gap between applications and theories. To verify vibration characteristics and long-term performance of pile-plank-supported low subgrade of ballastless track and the benefit of pile-board structure, an experimental study was conducted on low subgrade of pile-board under excitation loads using both in situ frequency sweeping and cyclic loading experiments. The frequency sweeping experimental results show that the pile-plank-supported low subgrade has smooth stiffness along the longitudinal subgrade and can effectively control the progressive effects of train speed on dynamic stiffness of the subgrade, which ensures driving safety and comfort. The cycle loading experimental results show that the pile-plank-supported low subgrade has favorable long-term dynamic stability, and its dynamic response is uniform along the longitudinal subgrade.

  14. Weathering the empire: meteorological research in the early British Straits Settlements.

    Science.gov (United States)

    Williamson, Fiona

    2015-09-01

    This article explores meteorological interest and experimentation in the early history of the Straits Settlements. It centres on the establishment of an observatory in 1840s Singapore and examines the channels that linked the observatory to a global community of scientists, colonial officers and a reading public. It will argue that, although the value of overseas meteorological investigation was recognized by the British government, investment was piecemeal and progress in the field often relied on the commitment and enthusiasm of individuals. In the Straits Settlements, as elsewhere, these individuals were drawn from military or medical backgrounds, rather than trained as dedicated scientists. Despite this, meteorology was increasingly recognized as of fundamental importance to imperial interests. Thus this article connects meteorology with the history of science and empire more fully and examines how research undertaken in British dependencies is revealing of the operation of transnational networks in the exchange of scientific knowledge.

  15. Comprehensive Monitoring of Wildlife Mortality on British Columbia Highways Using the WARS System (1978 to 2005)

    OpenAIRE

    Sielecki, Leonard E.

    2005-01-01

    The British Columbia Ministry of Transportation (BCMoT) has been operating its Wildlife Accident Reporting System (WARS) for almost three decades. Detailed information on motor vehicle-related wildlife mortality is systematically collected on a daily basis on major highways throughout British Columbia. Since its inception, WARS has become an increasingly valuable tool for highway planning and operational purposes. With WARS, BCMoT is able to support the British Columbia Government’s commitmen...

  16. Numerical Analysis of Piles in Layered Soils: A Parametric Study

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Reddy C

    2015-04-01

    Full Text Available In this paper, numerical analysis of a pile-soil interaction problem is presented considering the parameters influencing the axial load-deformation behavior of the pile embedded in a layered soil medium. The analysis is demonstrated with parametric solutions of a pile with underlain model soil strata under the axial force. An attempt is made to ascertain the extent of influence of elastic properties of the pile, geometry of the pile, end conditions of the pile and the elastic properties of the underlain soil strata on the response of the piles under axial loads lying in a model soil layers in terms of the settlement of the pile and the internal deformation of the pile. The study revealed that the increase in modulus of elasticity of pile improves the settlement resistance of the pile, increase in the ratio of cross sectional dimensions causes decrease in the top deformations of the pile, the settlement of the pile reduced to a great extent when the cross section of the pile adopted is non circular instead of circular and increase in the elastic modulii of top and bottom layers of soil has decreased the settlement of the pile to a great extent, but elastic modulus of soil layers other than top and bottom has got negligible influence on the settlement of the pile.

  17. 30 CFR 77.214 - Refuse piles; general.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; general. 77.214 Section 77.214... Installations § 77.214 Refuse piles; general. (a) Refuse piles constructed on or after July 1, 1971, shall be..., tipples, or other surface installations and such piles shall not be located over abandoned openings...

  18. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal mine waste: Refuse piles. 816.83 Section... ACTIVITIES § 816.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 816.81, the... drainage may not be diverted over the outslope of the refuse piles. Runoff from the areas above the...

  19. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal mine waste: Refuse piles. 817.83 Section... ACTIVITIES § 817.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 817.81, the... drainage may not be diverted over the outslope of the refuse pile. Runoff from areas above the refuse...

  20. Experimental study of soil arching of geogrid-reinforced and pile-supported widening embankment%桩-网加固拓宽路堤土拱效应试验研究

    Institute of Scientific and Technical Information of China (English)

    吕伟华; 缪林昌; 王非; 蔡海粟; 张成相

    2013-01-01

    Soil arching is very important for analyzing the stress state of existing and widening embankment and differential settlement between piles (caps) and subsoil. In this paper, the behavior of soil arching is analyzed for a widening embankment which is supported by rigid piles with caps and reinforced by geogrid. Based on the test site of the widening expressway project, earth pressures on caps and subsoil at the bottom and at different depths to fill surface are investigated; and tensile strains of the geogrid are monitored too. Then stress concentration ratios and soil arching ratios are analyzed and compared with several current design methods, including the Guido method, the BS8006 method, the Kempfert method and the Low method. Results show that, a two-dimensional plane soil arching fill load distribution on caps and subsoil within a critical arch height which is deduced to be 2.0 m owing a ratio of 1.4 the pile clear spacing, and is consistent with BS8006. The Guido and BS8006 methods were too conservative on assessing tensile strain of geogrid; Except for the Guido method, all rest presented design methods underestimated the resistance from the compressible subsoil. So, further study and a better understanding of soil arching should be developed.%  采用桩-网加固拓宽路堤时,土拱效应对于分析新老路堤应力分布和差异沉降有至关重要的作用。依托某高速公路路堤拓宽项目对土拱效应进行研究,对试验段新路堤填筑过程及运营时基底桩及桩间土不同位置处土压力、加筋层拉应变进行监测,得到二维平面土拱效应的变化规律,并利用已有土拱效应计算方法对现场实测结果进行对比验证。结果表明,平面土拱作用范围在一定高度范围内,试验段约为2.0 m,即拱高、拱跨之比约为1.4,与英国规范 BS8006[1]相近;按 Guido 法[2]与 BS8006法[3]进行土工格栅的设计均过于保守,除 Guido 法以外,几种方

  1. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    International Nuclear Information System (INIS)

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 μm were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile’s radius.

  2. Efficient stock piling of 40mm shells

    Directory of Open Access Journals (Sweden)

    J. N. Nanda

    1958-10-01

    Full Text Available A problem was posed as to discuss efficient stock-piling of 40mm shells. There is, in fact no data from which emergency requirements can be deduced. A figure has been quoted by Army authorities that E rounds per month are required during an emergency. The size of the emergency stock pile will depend upon the difference of the normal peace time production, and also on the time taken for the crash programme of emergency production to come into fulfillment. In addition the delivery time from factories to the stock piles is also kept in view.

  3. Experimental investigation of thermal balance of a turbocharged SI engine operating on natural gas

    International Nuclear Information System (INIS)

    This paper experimentally investigates the thermal balance and performance of a turbocharged gas spark ignition engine. The First Law of Thermodynamics was used for control volume around the engine to compute the output power, transferred energy to the cooling fluid, exhaust gases and also unaccounted losses through convection and radiation heat transfer. Thermal balance tests were performed for various operational conditions including full and half loads and different cooling fluid temperatures. Results indicate that by increasing engine load and coolant temperature, the percentage of transferred energy to the exhaust gases increased while the percentage of coolant energy decreased. Also, experimental data reveals that using gaseous fuel and a turbocharger (TC) in the engine leads to 4.5% and 4% more thermal efficiency than gasoline and natural aspirated (NA), respectively. Also, second law analysis reveals that using a turbocharger leads to a 3.6% increase in exergetic efficiency of the engine, averagely. Based on experimental results, an empirical correlation was suggested for computing the energy of exhaust gases which shows good agreement with the experimental data for the majority of operating conditions. -- Highlights: • Thermal balance of a turbocharged gas SI engine was investigated experimentally. • By increasing load and coolant temperature, transferred energy to exhaust increased. • Coolant energy percentage decreased by increasing the load and coolant temperature. • Gaseous fuel and a turbocharger (TC) lead to 4.5% and 4% more thermal efficiency. • An empirical correlation was suggested for computing the energy of exhaust gases

  4. Gas Bearing Control for Safe Operation in Critical Speed Regions - Experimental Verification

    DEFF Research Database (Denmark)

    Theisen, Lukas R. S.; Niemann, Hans H.; Galeazzi, Roberto;

    2015-01-01

    and deceleration patterns and avoidance of operation near the critical speeds, which is a limiting factor during operation, specially during run-downs. An approach for reducing the vibrations is by feedback controlled lubrication. This paper addresses the challenge of reducing vibrations in rotating machines......Gas bearings are popular for their high speed capabilities, low friction and clean operation, but require low clearances and suffer from poor damping properties. The poor damping properties cause high disturbance amplification near the natural frequencies. These become critical when the rotation...... supported by gas bearings to extend their operating range. Using H∞-design methods, active lubrication techniques are proposed to enhance the damping, which in turn reduces the vibrations to a desired safe level. The control design is validated experimentally on a laboratory test rig, and shown to allow...

  5. Operational experience and upgrading program of the experimental fast reactor JOYO

    International Nuclear Information System (INIS)

    Twenty years of successful operations at the experimental fast reactor JOYO provide a wealth of experience covering core management, chemical analysis of sodium and cover gas for impurity control, natural convection tests, upgrade of fuel failure detection system, corrosion product measurement, development of operation and maintenance support system, and replacement of major components in the cooling systems. Some of the data obtained is stored in a database to preserve the related knowledge. This experience and accumulated data will be useful for the design of future fast reactors. (author)

  6. Experimental demonstration of resonant-tunneling-diode operation beyond quasibound-state-lifetime limit

    International Nuclear Information System (INIS)

    We show, first, that the charge relaxation (response) time of resonant-tunneling diode (RTD) can be significantly shorter or longer than the resonant-state lifetime, depending on RTD operating point and RTD parameters. Coulomb interaction of electrons is responsible for the effect. Second, we demonstrate that the operating frequencies of RTDs are limited neither by resonant-state lifetime, nor by relaxation time; particularly in the RTDs with heavily doped collector, the differential conductance can stay negative at the frequencies far beyond the limits imposed by both time constants. We provide experimental evidences for both effects.

  7. Experimental demonstration of resonant-tunneling-diode operation beyond quasibound-state-lifetime limit

    Energy Technology Data Exchange (ETDEWEB)

    Feiginov, M N [Technische Universitaet Darmstad, 64283 Darmstadt (Germany); Chowdhury, D Roy, E-mail: feiginov@ont.tu-darmstadt.d [Universitaet Duisburg-Essen, 47057 Duisburg (Germany)

    2009-11-15

    We show, first, that the charge relaxation (response) time of resonant-tunneling diode (RTD) can be significantly shorter or longer than the resonant-state lifetime, depending on RTD operating point and RTD parameters. Coulomb interaction of electrons is responsible for the effect. Second, we demonstrate that the operating frequencies of RTDs are limited neither by resonant-state lifetime, nor by relaxation time; particularly in the RTDs with heavily doped collector, the differential conductance can stay negative at the frequencies far beyond the limits imposed by both time constants. We provide experimental evidences for both effects.

  8. Noise reduction by the application of an air-bubble curtain in offshore pile driving

    Science.gov (United States)

    Tsouvalas, A.; Metrikine, A. V.

    2016-06-01

    Underwater noise pollution is a by-product of marine industrial operations. In particular, the noise generated when a foundation pile is driven into the soil with an impact hammer is considered to be harmful for the aquatic species. In an attempt to reduce the ecological footprint, several noise mitigation techniques have been investigated. Among the various solutions proposed, the air-bubble curtain is often applied due to its efficacy in noise reduction. In this paper, a model is proposed for the investigation of the sound reduction during marine piling when an air-bubble curtain is placed around the pile. The model consists of the pile, the surrounding water and soil media, and the air-bubble curtain which is positioned at a certain distance from the pile surface. The solution approach is semi-analytical and is based on the dynamic sub-structuring technique and the modal decomposition method. Two main results of the paper can be distinguished. First, a new model is proposed that can be used for predictions of the noise levels in a computationally efficient manner. Second, an analysis is presented of the principal mechanisms that are responsible for the noise reduction due to the application of the air-bubble curtain in marine piling. The understanding of these mechanisms turns to be crucial for the exploitation of the maximum efficiency of the system. It is shown that the principal mechanism of noise reduction depends strongly on the frequency content of the radiated sound and the characteristics of the bubbly medium. For piles of large diameter which radiate most of the acoustic energy at relatively low frequencies, the noise reduction is mainly attributed to the mismatch of the acoustic impedances between the seawater and the bubbly layer. On the contrary, for smaller piles and when the radiated acoustic energy is concentrated at frequencies close to, or higher than, the resonance frequency of the air bubbles, the sound absorption within the bubbly layer

  9. Dynamic Instability of Pile-Supported Structures in Liquefiable Soils during Earthquakes

    Directory of Open Access Journals (Sweden)

    S. Adhikari

    2008-01-01

    Full Text Available Piles are long slender columns installed deep into the ground to support heavy structures such as oil platforms, bridges, and tall buildings where the ground is not strong enough to support the structure on its own. In seismic prone zones, in the areas of soft soils (loose to medium dense soil which liquefies like a quick sand piles are routinely used to support structures (buildings/ bridges. The pile and the building vibrate, and often collapse, in liquefiable soils during major earthquakes. In this paper an experimental and analytical approach is taken to characterize this vibration. The emphasis has been given to the dynamic instability of piled foundations in liquefied soil. The first natural frequency of a piled-structure vibrating in liquefiable soil is obtained from centrifuge tests. The experimental system is modelled using a fixed-free Euler-Bernoulli beam resting against an elastic support with axial load and tip mass with rotary inertia. Natural frequencies obtained from the analytical method are compared with experimental results. It was observed that the effective natural frequency of the system can reduce significantly during an earthquake.

  10. Experimental and Numerical Characterization of CaPaMan 2bis Operation

    Directory of Open Access Journals (Sweden)

    E. E. Hernandez‐Martinez

    2010-04-01

    Full Text Available In this paper, the operation performance of CaPaMan 2bis (Cassino Parallel Manipulator 2 bis was investigated through labexperimental tests and computer simulations. Milli‐CaTraSys (Milli‐Cassino Tracking System was implemented to determinedisplacements and orientation variations of CaPaMan 2bis end‐effector during experimental tests. A 3D (three dimensionvirtual model was built in ADAMS environment to simulate the operation behavior for different prescribed motions. Severalprescribed motions have been simulated and tested under different conditions in order to characterize the system behavior. Inparticular, the kinematic characteristics were obtained from both, experimental tests and numerical simulations. Finally,experiment results and simulation computations were compared for purpose of performance evaluation and designcharacterization of the parallel manipulator structure and its prototype.

  11. Experimental research on dynamic operating characteristics of a novel silica gel-water adsorption chiller

    Institute of Scientific and Technical Information of China (English)

    WANG Dechang; WU Jingyi; WANG Ruzhu; DOU Weidong

    2007-01-01

    A novel silica gel-water adsorption chiller consisting of two adsorption/desorption chambers and an evaporator with one heat-pipe working chamber is experimentally studied.The dynamic operating characteristics of the chiller and the thermodynamic characteristics of the adsorber are obtained.The experimental results show that the dynamic operating characteristics of the chiller and the thermodynamic characteristics of the adsorber are satisfactory and that the cycle is a novel and effective adsorption cycle.A mass recovery process increases the cyclic adsorption capacity of the system and improves adaptability of the chiller to a lowgrade heat source.In addition,the experiment indicates that this novel chiller is highly suitable for an air conditioning system with a low dehumidification requirement or a system with a large cycle flowrate and an industrial cooling water system.

  12. INTERACTION BETWEEN LONG PILES AND THE SOIL BODY AS PART OF THE SLAB-PILE FOUNDATION

    OpenAIRE

    Ter-Martirosyan ZavenGrigorevich; Trinh Tuan Viet

    2012-01-01

    The paper provides a definition of and a solution to the problems of interaction between long piles and the soil body as part of the slab-pile foundation with the due account for the interval between the piles, the length of piles and their correlations, as well as the nonlinear properties of soil identified by analytical and numerical methods through the application of Plaxis-2d software. It is proven that the above properties produce a substantial impact onto the stress-strain state of s...

  13. Modelling the dynamic pile-soil-pile interaction in a multi-layered half-space

    OpenAIRE

    Hamad, Waleed; Ntotsios, Evangelos; Hunt, Hugh; Hussein, M.F.M.; Thompson, D. J.; Talbot, James

    2015-01-01

    Within the context of railway ground-borne vibration, the dynamic pile-soil-pile interaction remains an area that has not been sufficiently investigated. Whilest a number of researchers have scrutinised the vibration response of piled-foundations, their approaches exhibit a compromise between computation time and solution accuracy. In this paper, two models of piled-foundations in a multi-layered half-space are presented; one is an efficient semi-analytical model and another is a fully-couple...

  14. The Effect of Soil-Pile Interface Behaviour on Laterally Loaded Piles

    DEFF Research Database (Denmark)

    Zania, Varvara; Hededal, Ole

    2011-01-01

    In current practice it is either the p – y curve concept, or analytical solutions assuming different formulations for ultimate soil resistance that are being used to evaluate the lateral pile response. The adequacy of the p – y curves or of the assumed pressure distribution and ultimate soil...... resistance have been questioned. In this study the lateral capacity of three-dimensional numerical models of rigid piles embedded in cohesionless soil was estimated. The potential variability of the friction properties along the perimeter of the pile was considered. The interface properties affect...... the ultimate soil resistance and the stiffness of the soil–pile response....

  15. Experimental study on burying technology of fiber grating Sensor system in driven pile%光纤光栅传感系统在打入桩中的埋设工艺试验研究

    Institute of Scientific and Technical Information of China (English)

    冯春; 李世海; 刘天苹; 许利凯; 王观石; 谷雨雷

    2009-01-01

    According to test status of fiber Bragg grating( FBG) sensor system applied to a concrete piles project, the anti-hitting performance of the sensor system is evaluated. Due to experiments, the flange joints and nearby regions are mostly prone to damage,the data connecting cables are also easy to breakage,while the FBG sensors are the most difficult to destroy. According to results of experiment, the corresponding protection measures are adopted. The glue-felt, plastic pipe and twine are used to protect the FBG sensor system, and the effect of the protection approach is approved by the experiment.%根据光纤Bragg光栅(FBG)传感系统应用于某工程混凝土管桩测试的现状,对该传感系统的抗击打性能进行了试验评价,发现法兰盘接头和附近的区域最易发生破坏,数据连接线也易损坏,而FBG传感器最不易破坏.根据以上试验结果,提出了相应的减振措施,采用粘扣、塑料管、麻绳等手段进行保护,并通过试验验证了此种保护措施的减振效果.

  16. An experimental investigation of the effects of alarm processing and display on operator performance

    Energy Technology Data Exchange (ETDEWEB)

    O`Hara, J.; Brown, W. [Brookhaven National Lab., Upton, NY (United States). Dept. of Advanced Technology; Hallbert, B.; Skraaning, G. [Halden Reactor Project (Norway); Wachtel, J.; Persensky, J. [Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research

    1998-03-01

    This paper describes a research program sponsored by the US Nuclear Regulatory Commission to address the human factors engineering (HFE) aspects of nuclear power plant alarm systems. The overall objective of the program is to develop HFE review guidance for advanced alarm systems. As part of this program, guidance has been developed based on a broad base of technical and research literature. In the course of guidance development, aspects of alarm system design for which the technical basis was insufficient to support complete guidance development were identified. The primary purpose of the research reported in this paper was to evaluate the effects of three of these alarm system design characteristics on operator performance in order to contribute to the understanding of potential safety issues and to provide data to support the development of design review guidance in these areas. Three alarm system design characteristics studied were (1) alarm processing (degree of alarm reduction), (2) alarm availability (dynamic prioritization and suppression), and (3) alarm display (a dedicated tile format, a mixed tile and message list format, and a format in which alarm information is integrated into the process displays). A secondary purpose was to provide confirmatory evidence of selected alarm system guidance developed in an earlier phase of the project. The alarm characteristics were combined into eight separate experimental conditions. Six, two-person crews of professional nuclear power plant operators participated in the study. Following training, each crew completed 16 test trials which consisted of two trials in each of the eight experimental conditions (one with a low-complexity scenario and one with a high-complexity scenario). Measures of process performance, operator task performance, situation awareness, and workload were obtained. In addition, operator opinions and evaluations of the alarm processing and display conditions were collected. No deficient

  17. Local Scour Around Piles Under Wave Action

    Institute of Scientific and Technical Information of China (English)

    陈国平; 左其华; 黄海龙

    2004-01-01

    The model tests are performed with regular waves, and the effect of wave height, wave period, water depth, scdiment size and pile diameter is evaluated. The shape and size of local scour around piles are studied. There are three typical scour patterns due to wave action. It is found that a relationship exists between the erosion depth and the wave number. An empirical formula of the maximum local scour is thus derived.

  18. Monitoring natural sequestration of carbon dioxide into chrysotile milling waste piles

    Science.gov (United States)

    Lemieux, J.; Beaudoin, G.; Pronost, J.; Constantin, M.; Duchesne, J.; Hebert, R.; Larachi, F.; Maldague, X.; Molson, J. W.; Tremblay, J.

    2010-12-01

    Chrysotile milling waste piles are naturally, passively and permanently stripping carbon dioxide from the atmosphere by mineral carbonation reactions at the surface and within the piles. Serpentines react with CO2 and water to yield hydrated magnesium carbonates. The reaction is exothermic and warm air vents capable of melting snow have been discovered at the upper surface of a chrysotile milling waste pile holding 130 Mt of serpentinized ultramafic rocks, accumulated since 1953, at the Black Lake mine, Québec, Canada. The warm air vents are otherwise inconspicuous at the surface of the milling waste piles. The warm air vent temperatures ranged from 7.0 to 18.5 °C from March 2009 to July 2010, as measured with a thermocouple placed in the venting area identified by infrared photography. During this time, the temperature of ambient air ranged from -13.4 to 10 °C. Measurements of CO2 concentration using a Li-Cor Li-8100 equipped with a 10-cm survey chamber yielded values as low as 10 ppm CO2 during winter 2010, which is much lower than measured atmospheric CO2, which is about 390 ppm. In order to better understand the reaction, laboratory experiments and field work are being conducted. Preliminary laboratory experiments have shown that the reaction is relatively fast and is depending strongly on humidity and CO2 supply. An experimental small-scale pile was also constructed in which the temperature, volumetric water content, gas pressure and gas composition are monitored at different depth along a cross section. The pile is 2 m high with a surface of about 100 m2 and made of fresh milling wastes. Infiltration within the pile is monitored as well as water composition running out of the pile. The observation of the carbonatation reaction in this experimental milling pile is expected to provide invaluable insights about the natural reaction taking place in the full-scale piles and may provide an estimate of captured CO2 since their construction.

  19. Indians Repulse British With Rocket

    Science.gov (United States)

    2004-01-01

    During the early introduction of rockets to Europe, they were used only as weapons. Enemy troops in India repulsed the British with rockets. Later, in Britain, Sir William Congreve developed a rocket that could fire to about 9,000 feet. The British fired Congreve rockets against the United States in the War of 1812.

  20. Nonlinear calculating method of pile settlement

    Institute of Scientific and Technical Information of China (English)

    贺炜; 王桂尧; 王泓华

    2008-01-01

    To study calculating method of settlement on top of extra-long large-diameter pile, the relevant research results were summarized. The hyperbola model, a nonlinear load transfer function, was introduced to establish the basic differential equation with load transfer method. Assumed that the displacement of pile shaft was the high order power series of buried depth, through merging the same orthometric items and arranging the relevant coefficients, the solution which could take the nonlinear pile-soil interaction and stratum properties of soil into account was solved by power series. On the basis of the solution, by determining the load transfer depth with criterion of settlement on pile tip, the method by making boundary conditions compatible was advised to solve the load-settlement curve of pile. The relevant flow chart and mathematic expressions of boundary conditions were also listed. Lastly, the load transfer methods based on both two-broken-line model and hyperbola model were applied to analyzing a real project. The related coefficients of fitting curves by hyperbola were not less than 0.96, which shows that the hyperbola model is truthfulness, and is propitious to avoid personal error. The calculating value of load-settlement curve agrees well with the measured one, which indicates that it can be applied in engineering practice and making the theory that limits the design bearing capacity by settlement on pile top comes true.

  1. Grouting of uranium mill tailings piles

    International Nuclear Information System (INIS)

    A program of remedial action was initiated for a number of inactive uranium mill tailings piles. These piles result from mining and processing of uranium ores to meet the nation's defense and nuclear power needs and represent a potential hazard to health and the environment. Possible remedial actions include the application of covers to reduce radon emissions and airborne transport of the tailings, liners to prevent groundwater contamination by leachates from the piles, physical or chemical stabilization of the tailings, or moving the piles to remote locations. Conventional installation of liners would require excavation of the piles to emplace the liner; however, utilization of grouting techniques, such as those used in civil engineering to stabilize soils, might be a potential method of producing a liner without excavation. Laboratory studies on groutability of uranium mill tailings were conducted using samples from three abandoned piles and employing a number of particulate and chemical grouts. These studies indicate that it is possible to alter the permeability of the tailings from ambient values of 10-3 cm/s to values approaching 10-7 cm/s using silicate grouts and to 10-8 cm/s using acrylamide and acrylate grouts. An evaluation of grouting techniques, equipment required, and costs associated with grouting were also conducted and are presented. 10 references, 1 table

  2. Crazy heart: kinematics of the "star pile" in Abell 545

    Science.gov (United States)

    Salinas, R.; Richtler, T.; West, M. J.; Romanowsky, A. J.; Lloyd-Davies, E.; Schuberth, Y.

    2011-04-01

    We study the structure and internal kinematics of the "star pile" in Abell 545 - a low surface brightness structure lying in the center of the cluster. We have obtained deep long-slit spectroscopy of the star pile using VLT/FORS2 and Gemini/GMOS, which is analyzed in conjunction with deep multiband CFHT/MEGACAM imaging. As presented in a previous study the star pile has a flat luminosity profile and its color is consistent with the outer parts of elliptical galaxies. Its velocity map is irregular, with parts being seemingly associated with an embedded nucleus, and others which have significant velocity offsets to the cluster systemic velocity with no clear kinematical connection to any of the surrounding galaxies. This would make the star pile a dynamically defined stellar intra-cluster component. The complicated pattern in velocity and velocity dispersions casts doubts on the adequacy of using the whole star pile as a dynamical test for the innermost dark matter profile of the cluster. This status is fulfilled only by the nucleus and its nearest surroundings which lie at the center of the cluster velocity distribution. Based on observations taken at the European Southern Observatory, Cerro Paranal, Chile, under programme ID 080.B-0529. Also based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil) and SECYT (Argentina); and on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National

  3. Videotaped Feedback Method to Enhance Learning in Preclinical Operative Dentistry: An Experimental Study.

    Science.gov (United States)

    Shah, Dipali Yogesh; Dadpe, Ashwini Manish; Kalra, Dheeraj Deepak; Garcha, Vikram P

    2015-12-01

    The aim of this study was to investigate if a videotaped feedback method enhanced teaching and learning outcomes in a preclinical operative laboratory setting for novice learners. In 2013, 60 dental students at a dental school in India were randomly assigned to two groups: control (n=30) and experimental (n=30). The control group prepared a Class II tooth preparation for amalgam after receiving a video demonstration of the exercise. The experimental group received the same video demonstration as the control group, but they also participated in a discussion and analysis of the control groups' videotaped performance and then performed the same exercise. The self-evaluation scores (SS) and examiner evaluation scores (ES) of the two groups were compared using the unpaired t-test. The experimental group also used a five-point Likert scale to rate each item on the feedback form. The means of SS (13.65±2.43) and ES (14.75±1.97) of the experimental group were statistically higher than the means of SS (11.55±2.09) and ES (11.60±1.82) of the control group. Most students in the experimental group perceived that this technique enhanced their learning experience. Within the limits of this study, the videotaped feedback using both ideal and non-ideal examples enhanced the students' performance. PMID:26632301

  4. Transition from Research to Operations: Assessing Value of Experimental Forecast Products within the NWSFO Environment

    Science.gov (United States)

    Lapenta, William M.; Wohlman, Richard; Bradshaw, Tom; Burks, Jason; Jedlovec, Gary; Goodman, Steve; Darden, Chris; Meyer, Paul

    2003-01-01

    The NASA Short-term Prediction Research and Transition (SPoRT) Center seeks to accelerate the infusion of NASA Earth Science Enterprise (ESE) observations, data assimilation and modeling research into NWS forecast operations and decision-making. To meet long-term program expectations, it is not sufficient simply to give forecasters sophisticated workstations or new forecast products without fully assessing the ways in which they will be utilized. Close communication must be established between the research and operational communities so that developers have a complete understanding of user needs. In turn, forecasters must obtain a more comprehensive knowledge of the modeling and sensing tools available to them. A major goal of the SPoRT Program is to develop metrics and conduct assessment studies with NWS forecasters to evaluate the impacts and benefits of ESE experimental products on forecast skill. At a glance the task seems relatively straightforward. However, performing assessment of experimental products in an operational environment is demanding. Given the tremendous time constraints placed on NWS forecasters, it is imperative that forecaster input be obtained in a concise unobtrusive manor. Great care must also be taken to ensure that forecasters understand their participation will eventually benefit them and WFO operations in general. Two requirements of the assessment plan developed under the SPoRT activity are that it 1) Can be implemented within the WFO environment; and 2) Provide tangible results for BOTH the research and operational communities. Supplemental numerical quantitative precipitation forecasts (QPF) were chosen as the first experimental SPoRT product to be evaluated during a Pilot Assessment Program conducted 1 May 2003 within the Huntsville AL National Weather Service Forecast Office. Forecast time periods were broken up into six- hour bins ranging from zero to twenty-four hours. Data were made available for display in AWIPS on an

  5. Experimental Investigation of Factors Influencing Operating Rotor Tip Clearance in Multistage Compressors

    Directory of Open Access Journals (Sweden)

    Reid A. Berdanier

    2015-01-01

    Full Text Available An analysis of compressor rotor tip clearance measurements using capacitance probe instrumentation is discussed for a three-stage axial compressor. Thermal variations and centrifugal effects related to rotational speed changes affect clearance heights relative to the assembled configuration. These two primary contributions to measured changes are discussed both independently and in combination. Emphasis is given to tip clearance changes due to changing loading condition and at several compressor operating speeds. Measurements show a tip clearance change approaching 0.1 mm (0.2% rotor span when comparing a near-choke operating condition to a near-stall operating condition for the third stage. Additional consideration is given to environmental contributions such as ambient temperature, for which changes in tip clearance height on the order of 0.05 mm (0.1% rotor span were noted for temperature variations of 15°C. Experimental compressor operating clearances are presented for several temperatures, operating speeds, and loading conditions, and comparisons are drawn between these measured variations and predicted changes under the same conditions.

  6. Experimental study on operating parameters of miniature loop heat pipe with flat evaporator

    International Nuclear Information System (INIS)

    Miniature loop heat pipe (MLHP) with flat evaporator has been proved that it has the capability to fulfill the demand for the thermal management of high-power electronic system. To employ MLHP into practical application and obtain the best operating parameters, a copper-water MLHP with flat evaporator of 8 mm thick was fabricated and tested in the condition of different condenser locations and operating orientations. The results show that the condenser located close to the evaporator outlet and adverse orientation have positive impact on the operating temperature of the loop, but negative impact on the cooling capability of condenser. For better understanding of their effect on the heat transfer characteristics of MLHP, the start-up behaviors, thermal performance and the operating regimes are explored in detail. - Highlights: ► A copper-water MLHP with flat evaporator of only 8 mm thick was fabricated. ► The MLHP can be applied to electronic cooling. ► The effect of condenser locations was investigated for the first time. ► The experimental results were discussed and analyzed comprehensively. ► Some practical solutions for disadvantages of LHP operation were provided.

  7. Study on pile drivability with one dimensional wave propagation theory

    Institute of Scientific and Technical Information of China (English)

    陈仁朋; 王仕方; 陈云敏

    2003-01-01

    Pile drivability is a key problem during the stage of design and construction installation of pile foundations. The solution to the one dimensional wave equation was used to determine the impact force at the top of a concrete pile for a given ram mass, cushion stiffness, and pile impedance. The kinematic equation of pile toe was established and solved based on wave equation theory. The movements of the pile top and pile toe were presented, which clearly showed the dynamic displacement, including rebound and penetration of pile top and toe. A parametric study was made with a full range of practical values of ram weight, cushion stiffness, dropheight, and pile impedance. Suggestions for optimizing the parameters were also presented. Comparisons between the results obtained by the present solution and in-situ measurements indicated the reliability and validity of the method.

  8. The Effect of the Propeller Jet on Pile Groups

    Institute of Scientific and Technical Information of China (English)

    Kubilay Cihan

    2014-01-01

    The objective of this study is to determine the effect of jet propeller on the damage of berthing structures combined of armoured slope with pile groups. For this purpose, scour measurements were performed for four types berthing structures, which were armoured slope with tandem arrangements of piles for two and three piles and with side by side arrangements of piles for two and three piles. The effect of gap between piles on damage was investigated. The damage level induced by propeller jet between piles was determined. The gaps were 1, 2, 3, and 4 times the pile diameter. Three different values of Rpm (690, 820, and 950) were chosen for the tests. The diameter of circular piles is 40 mm. The slope ratio was 1/3 and the diameter of propeller was 10 cm.

  9. Computing the modal mass from the state space model in combined experimental-operational modal analysis

    Science.gov (United States)

    Cara, Javier

    2016-05-01

    Modal parameters comprise natural frequencies, damping ratios, modal vectors and modal masses. In a theoretic framework, these parameters are the basis for the solution of vibration problems using the theory of modal superposition. In practice, they can be computed from input-output vibration data: the usual procedure is to estimate a mathematical model from the data and then to compute the modal parameters from the estimated model. The most popular models for input-output data are based on the frequency response function, but in recent years the state space model in the time domain has become popular among researchers and practitioners of modal analysis with experimental data. In this work, the equations to compute the modal parameters from the state space model when input and output data are available (like in combined experimental-operational modal analysis) are derived in detail using invariants of the state space model: the equations needed to compute natural frequencies, damping ratios and modal vectors are well known in the operational modal analysis framework, but the equation needed to compute the modal masses has not generated much interest in technical literature. These equations are applied to both a numerical simulation and an experimental study in the last part of the work.

  10. Experimental investigation of operating and dynamic properties of adsorption filter prototype

    Directory of Open Access Journals (Sweden)

    Raos Miomir

    2012-01-01

    Full Text Available The aim of the paper is an examination of flow-thermal, operating and dynamic properties (velocities of gas mixture, flows, pressure drops, temperature, humidity, chemical pollutants tests, and efficiency and performance of the adsorption filter prototype in the filter-ventilation system. The paper presents the results of the experimental research conducted on the original apparatus in the laboratory for air quality management at the Faculty of Occupational Safety in Niš. The examination of flow-thermal, operating and dynamic parameters of the observed filter prototype was carried out on an experimental ventilation setup with a variable flow rate of gas mixture. Experimental data were registered with appropriate measuring equipment, which helped us obtain a picture of the behavior of the adsorption filter prototype compared to simulated parameters of the gas mixture. By measuring and data acquisition, we reached the assumptions for identifying the observed process, and thus the possibility of modeling and controlling process parameters. [Projekat Ministarstva nauke Republike Srbije, br. III-43014

  11. Experimental study of operation performance of a low power thermoelectric cooling dehumidifier

    Directory of Open Access Journals (Sweden)

    Wang Huajun, Qi Chengying

    2010-05-01

    Full Text Available The present work was performed to apply thermoelectric technology to a low power dehumidifying device as an alternative to the conventional vapor-compression refrigeration systems. The experimental prototype of a small-scale thermoelectric dehumidifier (TED with rectangular cooling fins was built and its operation performance was studied experimentally. The results showed that the TED experienced two typical thermodynamic processes including the cooling dehumidification and the isothermal dehumidification, where the latter was dominated. It was found that there existed a peak during the variation of the average coefficient of performance (COP as a function of the input power of the thermoelectric module. Under the present experimental conditions, the COP of the TED reached the maximum of 0.32 and the corresponding dehumidifying rate was 0.0097 g/min, when the input power was kept at 6.0 W. The rapid elimination of condensed liquid-drops on the cooling fins amounted on the thermoelectric module is a major approach to improving the operation performance of the TED.

  12. Numerical modeling of Thermal Response Tests in Energy Piles

    Science.gov (United States)

    Franco, A.; Toledo, M.; Moffat, R.; Herrera, P. A.

    2013-05-01

    Nowadays, thermal response tests (TRT) are used as the main tools for the evaluation of low enthalpy geothermal systems such as heat exchangers. The results of TRT are used for estimating thermal conductivity and thermal resistance values of those systems. We present results of synthetic TRT simulations that model the behavior observed in an experimental energy pile system, which was installed at the new building of the Faculty of Engineering of Universidad de Chile. Moreover, we also present a parametric study to identify the most influent parameters in the performance of this type of tests. The modeling was developed using the finite element software COMSOL Multiphysics, which allows the incorporation of flow and heat transport processes. The modeled system consists on a concrete pile with 1 m diameter and 28 m deep, which contains a 28 mm diameter PEX pipe arranged in a closed circuit. Three configurations were analyzed: a U pipe, a triple U and a helicoid shape implemented at the experimental site. All simulations were run considering transient response in a three-dimensional domain. The simulation results provided the temperature distribution on the pile for a set of different geometry and physical properties of the materials. These results were compared with analytical solutions which are commonly used to interpret TRT data. This analysis demonstrated that there are several parameters that affect the system response in a synthetic TRT. For example, the diameter of the simulated pile affects the estimated effective thermal conductivity of the system. Moreover, the simulation results show that the estimated thermal conductivity for a 1 m diameter pile did not stabilize even after 100 hours since the beginning of the test, when it reached a value 30% below value used to set up the material properties in the simulation. Furthermore, we observed different behaviors depending on the thermal properties of concrete and soil. According to the simulations, the thermal

  13. Pile foundation of nuclear power plant structures

    International Nuclear Information System (INIS)

    The subject of pile foundation used for nuclear power plant structures, considering the experience gained by the designers of the Angra Nuclear Power Plant, Units 2 and 3 in Brazil is dealt with. The general concept of the pile foundations, including types and execution of the piles, is described briefly. Then the two basic models, i.e. the static model and the dynamic one, used in the design are shown, and the pertinent design assumptions as related to the Angra project are mentioned. The criteria which established the loading capacity of the piles are discussed and the geological conditions of the Angra site are also explained briefly, justifying the reasons why pile foundations are necessary in this project. After that, the design procedures and particularly the tools - i.e. the computer programs - are described. It is noted that the relatively simple but always time consuming job of loading determination calculations can be computerized too, as it was done on this project through the computer program SEASA. The interesting aspects of soil/structure interaction, applicable to static models, are covered in detail, showing the theoretical base wich was used in the program PILMAT. Then the advantage resulting from computerizing of the job of pile reinforcement design are mentioned, describing briefly the jobs done by the two special programs PILDES and PILTAB. The point is stressed that the effort computerizing the structural design of this project was not so much due to the required accuracy of the calculations, but mainly due to the need to save on the design time, as to allow to perform the design task within the relatively tight time schedule. A conclusion can be drawn that design of pile foundations for nuclear power plant structures is a more complex task than the design of bearing type of foundation for the same structures, but that the task can be always made easier when the design process can be computerized. (Author)

  14. Experimental Study ofa New Operative Procedure for Non-Ischemic Dilated Cardiomyopathy-Overlapping Cardiac Volume Reduction Operation

    Institute of Scientific and Technical Information of China (English)

    罗滨; 孟春营; 温定国; 松居喜朗; 安田庆秀

    2003-01-01

    Objectives To assess anewly devised procedure of cardiac volume reduction without resection of cardiac muscle and evaluated in experimental settings. Methods Ten beagle dogs underwent a rapid pacing leading to heart failure for 3 weeks and received the left ventricular reduction termed overlapping cardiac volume reduction operation (OLCVR) ,which consisted of a longitudinal incision in left ventricular (LV) free wall, sutures of the left marginal to the septal wall, and the right marginal to LV free wall.A slope of the linear preload recruitable stroke work relationship (Mw) , with a X - intercept (Vo) were calculated as the precise indicators of left ventricular systolic function. The constant of isovolumic pressure decay (Tau) and a peak filling rate (PFR) were also calculated as the indicators of LV diastolic function.Results LV end- diastolic dimensions was significantly reduced by OLCVR (43±2 to 25±1; mm).Fractional shortening was significantly improved by OLCVR (11±2 to 30±4;%). Mw (erg* cm-3* 103)was also significantly improved (21±2 to 33 ±3 (p<0. 001 ) ) , whereas Vo, Tau and PFR did not show significant changes. Conclusions The OLCVR significantly increased in the early LV systolic function without detrimental effects on diastolic function. This procedure may become a therapeutic option for end - stage cardiomyopathy.

  15. Wavelet analyses for stress wave detection of piles

    Institute of Scientific and Technical Information of China (English)

    WANG; Jingtao; (王靖涛)

    2003-01-01

    The theoretical foundation for application of wavelet analysis to pile integrity detection has been presented. The mechanism of spectral variations of reflected pulse from various defects in piles is explained by using the wave scattering theory. The theoretical analyses have been verified through the tests of model piles and a lot of engineering piles. A quantitative evaluation method for estimating damage degree of piles is proposed. The characteristic indexes describing spectrum variations of reflected signals and their critical values are given. They can be used not only to evaluate the damage degree but also to identify the kinds of pile defects.

  16. Influence of operation of national experimental nuclear reactor on the natural environment

    Directory of Open Access Journals (Sweden)

    Agnieszka Kaczmarek-Kacprzak

    2012-09-01

    Full Text Available This paper presents the impact of experimental nuclear reactor operations on the national environment, based on assessment reports of the radiological protection of active nuclear technology sources. Using the analysis of measurements carried out in the last 15 years, the trends are presented in selected elements of the environment on the Świerk Nuclear Centre site and its surroundings. In addition, the impact of research results is presented from the fi fteen year period of environmental analysis on building public confi dence on the eve of the start of construction of the first Polish nuclear power plant.

  17. Experimental Modeling of VHTR Plenum Flows during Normal Operation and Pressurized Conduction Cooldown

    Energy Technology Data Exchange (ETDEWEB)

    Glenn E McCreery; Keith G Condie

    2006-09-01

    The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. The present document addresses experimental modeling of flow and thermal mixing phenomena of importance during normal or reduced power operation and during a loss of forced reactor cooling (pressurized conduction cooldown) scenario. The objectives of the experiments are, 1), provide benchmark data for assessment and improvement of codes proposed for NGNP designs and safety studies, and, 2), obtain a better understanding of related phenomena, behavior and needs. Physical models of VHTR vessel upper and lower plenums which use various working fluids to scale phenomena of interest are described. The models may be used to both simulate natural convection conditions during pressurized conduction cooldown and turbulent lower plenum flow during normal or reduced power operation.

  18. British Energy - nuclear power in the private sector

    International Nuclear Information System (INIS)

    The first four months of the operation of British Energy as a privatised nuclear utility are briefly reviewed. Operational and financial performance have been good as exemplified by the figures for power output and financial return. Freedom from government control means that the options open to the company are much wider but the need to meet the expectations of shareholders is a major consideration. Added to this, the competitive nature of the electricity industry means that the cost reduction is important, though this cannot be at the expense of safety. Shareholder expectations make the funding of new nuclear power stations unrealistic at present. Increasingly, however, markets are opening up in the maintenance of existing plant and the decommissioning of older plant. The British Energy Group also has considerable expertise in the design, operation and management of power stations and of acting in a competitive energy market that could be exported. British Energy's International Division is in place to develop this potential. (UK)

  19. Resonant and nonresonant new phenomena of four-fermion operators for experimental searches

    Directory of Open Access Journals (Sweden)

    She-Sheng Xue

    2015-05-01

    Full Text Available In the fermion content and gauge symmetry of the standard model (SM, we study the four-fermion operators in the torsion-free Einstein–Cartan theory. The collider signatures of irrelevant operators are suppressed by the high-energy cutoff (torsion-field mass Λ, and cannot be experimentally accessible at TeV scales. Whereas the dynamics of relevant operators accounts for (i the SM symmetry-breaking in the domain of infrared-stable fixed point with the energy scale v≈239.5 GeV and (ii composite Dirac particles restoring the SM symmetry in the domain of ultraviolet-stable fixed point with the energy scale E≳5 TeV. To search for the resonant phenomena of composite Dirac particles with peculiar kinematic distributions in final states, we discuss possible high-energy processes: multi-jets and dilepton Drell–Yan process in LHC pp collisions, the resonant cross-section in e−e+ collisions annihilating to hadrons and deep inelastic lepton–hadron e−p scatterings. To search for the nonresonant phenomena due to the form-factor of Higgs boson, we calculate the variation of Higgs-boson production and decay rate with the CM energy in LHC. We also present the discussions on four-fermion operators in the lepton sector and the mass-squared differences for neutrino oscillations in short baseline experiments.

  20. Welding Techniques for In-Pile Instrumentation at INR Pitesti

    International Nuclear Information System (INIS)

    Welding is widely involved in developing in-pile instrumentation, regarding both attaching sensors and joining components of the in-pile experimental devices. Although new methods were not developed, we combined existing techniques, aiming to master them and to ensure reproducibility, sensitivity, robustness, and fast response (for sensor welding). In this paper we present results regarding thermocouple welded on cladding, and dissimilar joints. Techniques for welding K-type thermocouples on cladding were designated to ensure robust joints able to resist during pressure and temperature transients, to minimize the perturbation on temperature field and on the cladding material structure, to reproduce the joint shape and dimension, and to ensure fast response. Welded or brazed joints between materials with properties suitable to nuclear applications are often required for in-pile instrumentation to allow coupling to other components of the experimental devices. The paper describes work related to Zircaloy-to-Stainless Steel joint through eutectic vacuum brazing. The eutectic was produced by thermal diffusion of the elements in the base materials at their interface, through formation of liquid phases of Zr-Fe and Zr-Ni systems at the Zy-SS interface. Clean, reduced roughness, oxide-free contact interface, and precise temperature control were aimed. The optimal interface was the joint on perfectly matching truncated cone surfaces. Heating to 1030oC was obtained through vacuum induction at 10 kHz frequency, with vacuum between 10-5 and 10-6 mbar. Other dissimilar joints were micro-TIG welds on SS capillary connected to Inconel-Incoloy capsules, for high pressure measurement lines with small internal volume. To evaluate the joints burst tests (for thermocouple welding only) polarized light metallography, macrography, backscattered electron tests, Helium leak test, tensile test, and thermal cycling tests were performed. (author)

  1. Uranium migration and retention during weathering of a granitic waste rock pile

    International Nuclear Information System (INIS)

    Highlights: • We investigate the environmental impact of the granitic waste rock piles. • The majority of the waste rocks in the pile is barren- or overburden rock. • The main neo-formed U-bearing phases are (Ca) and (Cu) uranyl phosphates. • Under circum-neutral pH conditions they do not pose an environment threat. - Abstract: This study investigates the post-mining evolution of S-type granitic waste rocks around a former uranium mine, Vieilles Sagnes (Haute Vienne, NW Massif Central, France). This mine was operated between 1957 and 1965 in the La Crouzille former world-class uranium mining district and is representative of intra-granitic vein-type deposits. 50 years after mine closure and the construction and subsequent re-vegetation of the granitic waste rock pile, we evaluate the environmental evolution of the rock pile, including rock alteration, neo-formation of U-bearing phases during weathering, and U migration. Vertical trenches have been excavated through the rock pile down to an underlying paleo-soil, allowing the investigation of the vertical differentiation of the rock pile and its influence on water pathways, weathering processes and U migration and retention. Arenization dominantly drives liberation of U, by dissolution of uraninite inclusions in the most alterable granitic minerals (i.e. K-feldspar and biotite). Retention of U in the matrix at the base of the waste rock pile, and in the underlying paleo-soil most likely occurs by precipitation of (nano-) uranyl phosphates or a combination of co-precipitation and adsorption reactions of U onto Fe (oxy)hydroxides and/or clay minerals. Even though U-migration was observed, U is retained in stable secondary mineral phases, provided the current conditions will not be modified

  2. Edge scour at scour protections around piles in the marine environment - Laboratory and field investigation

    DEFF Research Database (Denmark)

    Petersen, Thor Ugelvig; Sumer, B. Mutlu; Fredsøe, Jørgen;

    2015-01-01

    waves and current. This paper presents an extensive experimental campaign to explain the edge scour process in current and combined irregular waves and current, as well as tidal current. The three-dimensional flow field around the pile and scour protection is resolved by particle image velocimetry...

  3. Alpha thalassaemia in British people.

    OpenAIRE

    Higgs, D R; Ayyub, H.; Clegg, J B; Hill, A V; Nicholls, R D; Teal, H; Wainscoat, J.S. (James S.); Weatherall, D. J.

    1985-01-01

    Although alpha thalassaemia is rare in north Europeans, it has been identified in British people with no known foreign ancestry. Twelve such patients were studied, of whom eight shared a distinctive molecular defect, which was clearly different from defects seen in subjects of Mediterranean or South East Asian origin. A rare but specific form of alpha thalassaemia is therefore present in the British population. In addition, two patients from families of mixed racial origin were encountered wh...

  4. Monte Carlo simulation of pulse pile-up effect in gamma spectrum of a PGNAA system

    Science.gov (United States)

    Mowlavi, Ali Asghar; Hadizadeh Yazdi, Mohammad Hadi

    2011-12-01

    We have applied a pile-up Monte Carlo simulation code on gamma spectrum of a prompt gamma neutron activation analysis (PGNAA) system. The code has been run in nonparalyzable mode for a specific geometry of a PGNAA system with 241Am-9Be source and NaI(Tl) detector to obtain the distortion due to “pile-up” in the pulse height of gamma spectrum. The results show that the main background in the nitrogen region of interest (ROI) is due to two pile-ups. We have also evaluated the variation of count rate and total photon sampling over the Monte Carlo spectra. At high count rates, not only the nitrogen ROI but also carbon ROI, and hydrogen peak are disturbed strongly. Comparison between the results of simulations and the experimental spectra has shown a good agreement. The code could be used for other source setups and different gamma detection systems.

  5. Monte Carlo simulation of pulse pile-up effect in gamma spectrum of a PGNAA system

    Energy Technology Data Exchange (ETDEWEB)

    Mowlavi, Ali Asghar, E-mail: amowlavi@sttu.ac.ir [Physics Department, School of Sciences, Sabzevar Tarbiat Moallem University, Sabzevar (Iran, Islamic Republic of); TRIL, ICTP, Trieste (Italy); Hadizadeh Yazdi, Mohammad Hadi [Physics Department, School of Sciences, Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of)

    2011-12-21

    We have applied a pile-up Monte Carlo simulation code on gamma spectrum of a prompt gamma neutron activation analysis (PGNAA) system. The code has been run in nonparalyzable mode for a specific geometry of a PGNAA system with {sup 241}Am-{sup 9}Be source and NaI(Tl) detector to obtain the distortion due to 'pile-up' in the pulse height of gamma spectrum. The results show that the main background in the nitrogen region of interest (ROI) is due to two pile-ups. We have also evaluated the variation of count rate and total photon sampling over the Monte Carlo spectra. At high count rates, not only the nitrogen ROI but also carbon ROI, and hydrogen peak are disturbed strongly. Comparison between the results of simulations and the experimental spectra has shown a good agreement. The code could be used for other source setups and different gamma detection systems.

  6. Monte Carlo simulation of pulse pile-up effect in gamma spectrum of a PGNAA system

    International Nuclear Information System (INIS)

    We have applied a pile-up Monte Carlo simulation code on gamma spectrum of a prompt gamma neutron activation analysis (PGNAA) system. The code has been run in nonparalyzable mode for a specific geometry of a PGNAA system with 241Am-9Be source and NaI(Tl) detector to obtain the distortion due to “pile-up” in the pulse height of gamma spectrum. The results show that the main background in the nitrogen region of interest (ROI) is due to two pile-ups. We have also evaluated the variation of count rate and total photon sampling over the Monte Carlo spectra. At high count rates, not only the nitrogen ROI but also carbon ROI, and hydrogen peak are disturbed strongly. Comparison between the results of simulations and the experimental spectra has shown a good agreement. The code could be used for other source setups and different gamma detection systems.

  7. Analysis of uplift loads of precast-concrete piles in porous soils

    Directory of Open Access Journals (Sweden)

    Stélio Maia Menezes

    2006-01-01

    Full Text Available This paper presents the analysis of uplift load tests in three precast-concrete piles carried out in a collapsible sandy soil. The piles with 12 meters (m length and 0.17 x 0.17 square meter (m2 cross section were instrumented with strain gauges, in order to know the load transfer in depth. Three tests performed in a slow maintained load way were conducted in a natural condition of moisture content soil. A fourth test was carried out after the previous soaking of the soil around the pile head. The tests were performed in the experimental research site at the Universidade Estadual Paulista “Júlio de Mesquita Filho” (Unesp. The results obtained were evaluated by analytical and empirical methods.

  8. Numerical and experimental investigation on the performance of safety valves operating with different gases

    International Nuclear Information System (INIS)

    A detailed analysis of the effect related to the expansion of different gases throughout safety relief valves is carried out both numerically and experimentally. The considered gases are air, argon and ethylene, representative of a wide range of specific heat ratios. A first experimental campaign performed in air and argon on a safety relief valve characterized by connection 1/2″ × 1″ and orifice designation D (diameter 10 mm) according to API 526 showed significant reduction both in disc lift and in exhausted mass flow rate, at the nominal overpressure, when operating with argon. In order to gain a deeper insight into the physics involved and to evaluate the valve behavior with other gases, an extensive numerical testing has been performed by means of an accurate CFD code based on discontinuous Galerkin formulation. Numerical results are at first validated against measurements obtained in air on a 2″ J 3″ safety relief valve proving a remarkable accuracy of the computational method. Then the validated solver is applied on the same computational grid using argon and ethylene as working fluids. The three gases are considered as thermally perfect gases. A critical discussion based on the numerical results allows to clarify the fluid dynamic and physical reasons causing the observed trends both in the opening force and in the discharge coefficient. The main conclusion is that particular care must be taken when a safety valve operates with a fluid characterized by a specific heat ratio greater than the one of the gas used during type testing. -- Highlights: ► Effects of different gases on the discharge capacity and operational characteristics on safety relief valves. ► Influence of different specific heat ratio on safety relief valves discharge coefficient. ► Skilful application of Discontinuous Galerkin CFD solver to safety valves performances prediction

  9. 1970 British Cohort Study

    Directory of Open Access Journals (Sweden)

    Matt Brown

    2014-10-01

    Full Text Available The 1970 British Cohort Study (BCS70 is one of Britain’s world famous national longitudinal birth cohort studies, three of which are run by the Centre for Longitudinal Studies at the Institute of Education, University of London.  BCS70 follows the lives of more than 17,000 people born in England, Scotland and Wales in a single week of 1970. Over the course of cohort members lives, the BCS70 has collected information on health, physical, educational and social development, and economic circumstances among other factors. Since the birth survey in 1970, there have been nine ‘sweeps’ of all cohort members at ages 5, 10, 16, 26, 30, 34, 38 and most recently at 42. Data has been collected from a number of different sources (the midwife present at birth, parents of the cohort members, head and class teachers, school health service personnel and the cohort members themselves. The data has been collected in a variety of ways including via paper and electronic questionnaires, clinical records, medical examinations, physical measurements, tests of ability, educational assessments and diaries. The majority of BCS70 survey data can be accessed by bona fide researchers through the UK Data Service at the University of Essex.

  10. Picking up Clues from the Discard Pile

    Science.gov (United States)

    2008-01-01

    As NASA's Phoenix Mars Lander excavates trenches, it also builds piles with most of the material scooped from the holes. The piles, like this one called 'Caterpillar,' provide researchers some information about the soil. On Aug. 24, 2008, during the late afternoon of the 88th Martian day after landing, Phoenix's Surface Stereo Imager took separate exposures through red, green and blue filters that have been combined into this approximately true-color image. This conical pile of soil is about 10 centimeters (4 inches) tall. The sources of material that the robotic arm has dropped onto the Caterpillar pile have included the 'Dodo' and ''Upper Cupboard' trenches and, more recently, the deeper 'Stone Soup' trench. Observations of the pile provide information, such as the slope of the cone and the textures of the soil, that helps scientists understand properties of material excavated from the trenches. For the Stone Soup trench in particular, which is about 18 centimeters (7 inches) deep, the bottom of the trench is in shadow and more difficult to observe than other trenches that Phoenix has dug. The Phoenix team obtained spectral clues about the composition of material from the bottom of Stone Soup by photographing Caterpillar through 15 different filters of the Surface Stereo Imager when the pile was covered in freshly excavated material from the trench. The spectral observation did not produce any sign of water-ice, just typical soil for the site. However, the bigger clumps do show a platy texture that could be consistent with elevated concentration of salts in the soil from deep in Stone Soup. The team chose that location as the source for a soil sample to be analyzed in the lander's wet chemistry laboratory, which can identify soluble salts in the soil. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed

  11. Transient response of piles-bridge under horizontal excitation

    Institute of Scientific and Technical Information of China (English)

    朱斌; 陈仁朋; 陈云敏

    2003-01-01

    Moving ships and other objects drifting on water often impact a bridge' s pile foundations. The mechanical model of the piles-bridge structure under horizontal forcing was established, and a time-domain approach based on Finite-difference Method was developed for analyzing the dynamic response of the piles-bridge structure. For a single pile, good agreement between two computed results validated the present approach.The slenderness ratio of the pile, the pile-soil stiffness ratio and the type of the structure influence the dynamic response of the piles-bridge structure. The computed results showed that the stiffness of the structure determines the dynamic response of the piles-bridge structure under horizontal forcing.

  12. Transient response of piles-bridge under horizontal excitation

    Institute of Scientific and Technical Information of China (English)

    朱斌; 陈仁朋; 陈云敏

    2003-01-01

    Moving ships and other objects drifting on water often impact a bridge's pile foundations. The mechanical model of the piles-bridge structure under horizontal forcing was established, and a time-domain approach based on Finite-difference Method was developed for analyzing the dynamic response of the piles-bridge structure. For a single pile, good agreement between two computed results validated the present approach. The slenderness ratio of the pile, the pile-soil stiffness ratio and the type of the structure influence the dynamic response of the piles-bridge structure. The computed results showed that the stiffness of the structure determines the dynamic response of the piles-bridge structure under horizontal forcing.

  13. Experimental identification and study of hydraulic resonance test rig with Francis turbine operating at partial load

    International Nuclear Information System (INIS)

    Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating vortex rope developing at the outlet of the runner induces pressure fluctuations which can excite the hydraulic system resonance, leading to undesirable large torque and power fluctuations. At resonant operating points, the prediction of amplitude pressure fluctuations by hydro-acoustic models breaks down and gives unreliable results. A more detailed knowledge of the eigenmodes and a better understanding of phenomenon occurring at resonance could allow improving the hydro-acoustic models prediction.This paper presents an experimental identification of a resonance observed in a close-looped hydraulic system with a Francis turbine reduced scale model operating at partial load. The resonance is excited matching one of the test rig eigenfrequencies with the vortex rope precession frequency. At this point, the hydro-acoustic response of the test rig is studied more precisely and used finally to reproduce the shape of the excited eigenmode.

  14. Experimental identification and study of hydraulic resonance test rig with Francis turbine operating at partial load

    Science.gov (United States)

    Favrel, A.; Landry, C.; Müller, A.; Avellan, F.

    2012-11-01

    Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating vortex rope developing at the outlet of the runner induces pressure fluctuations which can excite the hydraulic system resonance, leading to undesirable large torque and power fluctuations. At resonant operating points, the prediction of amplitude pressure fluctuations by hydro-acoustic models breaks down and gives unreliable results. A more detailed knowledge of the eigenmodes and a better understanding of phenomenon occurring at resonance could allow improving the hydro-acoustic models prediction.This paper presents an experimental identification of a resonance observed in a close-looped hydraulic system with a Francis turbine reduced scale model operating at partial load. The resonance is excited matching one of the test rig eigenfrequencies with the vortex rope precession frequency. At this point, the hydro-acoustic response of the test rig is studied more precisely and used finally to reproduce the shape of the excited eigenmode.

  15. 保留齿线痔上黏膜缝扎固定术治疗混合痔临床疗效评价%Clinical evaluation of suture-fixation operation above mucosal of piles with retaining dental line in treatment of mixed hemorrhoids

    Institute of Scientific and Technical Information of China (English)

    翟敏; 张永安; 周峰; 张旗; 徐慧磊; 孙琼

    2011-01-01

    目的 探讨保留齿线痔上黏膜缝扎固定术治疗混合痔的临床疗效.方法 对我科100例混合痔患者采用随机分组,50例采用保留齿线痔上黏膜缝扎固定术(治疗组),50例采用外剥内扎术(对照组),对两组疗效进行对比分析.结果 两组手术疗效相近(P >0.05),但治疗组术后疼痛、愈合时间、术后出血,评分均较对照组减少(P 0. 05), while scores in postoperative pain, healing time and postoperative bleeding were less in treatment group than that in control group ( P <0. 05). Conclusion Suture-fixation operation on the mucosal of piles with retaining dental line can not only eliminate symptoms induced by hemorrhoids but also protect anal function. It is a safe, effective and less postoperative pain operation.

  16. Noise Mitigation During Pile Driving Efficiently Reduces Disturbance of Marine Mammals.

    Science.gov (United States)

    Nehls, Georg; Rose, Armin; Diederichs, Ansgar; Bellmann, Michael; Pehlke, Hendrik

    2016-01-01

    Acoustic monitoring of harbor porpoises (Phocoena phocoena L., 1758) indicated a strongly reduced disturbance by noise emitted by pile driving for offshore wind turbine foundations insulated by a big bubble curtain (BBC). This newly developed noise mitigation system was tested during construction of the offshore wind farm Borkum West II (North Sea). Because porpoise activity strongly corresponded to the sound level, operation of the new system under its most suitable configuration reduced the porpoise disturbance area by ~90%. Hence, for the first time, a positive effect of a noise mitigation system during offshore pile driving on an affected marine mammal species could be demonstrated. PMID:26611029

  17. THE KINEMATIC AND INERTIAL SOIL-PILE INTERACTIONS: CENTRIFUGE MODELLING

    OpenAIRE

    Chenaf, Nawel; CHAZELAS, Jean-Louis

    2008-01-01

    International audience Piles supporting superstructures undergo with the soil two interactions during an earthquake: the kinematic interaction and the inertial interaction. The kinematic soil-pile interaction is the pile loading by the soil displacement produced by the seismic waves propagating. Inertial superstructure-pile-soil interaction results from forces due to the superstructure actuation by the kinematic interaction. These two interactions are superimposed in seismic events and the...

  18. The Tensile Capacity Of Bored Piles In Frictional Soils

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Andersen, Allan; Damkilde, Lars

    2008-01-01

    Three series of 10 piles each were installed in two different locations. The length of the piles varied from 2 to 6 m and the diameters were 14 and 25 cm. The piles were constructed above the groundwater table using continuous flight augers and the concrete was placed by gravity free fall....... The piles were tested to failure in axial uplift and the load-displacement relations were recorded....

  19. An Estimation of Internal Soliton Forces on a Pile in the Ocean

    Institute of Scientific and Technical Information of China (English)

    DU Tao; SUN Li; ZHANG Yijun; BAO Xianwen; FANG Xinhua

    2007-01-01

    Internal soliton forces on oil-platform piles in the ocean are estimated with the Morison Formula. Different from sur face wave forces, which change only in magnitude along a pile, internal soliton forces can be distributed over the entire pile in the water and they change not only in magnitude but also in direction with depth. Our calculations show that the maximum total force caused by a soliton with its associated current of 2.1 ms-1 is nearly equal to the maximum total force exerted by a surface wave with a wavelength of 300 m and a wave-height of 18 m. The total internal soliton force is large enough to affect the operations of marine oil platforms and other facilities. Therefore, the influence of internal solitons should not be neglected in the design of oil platforms.

  20. In-pile test of the crud separator system in the HBWR. (II)

    International Nuclear Information System (INIS)

    The out-of-pile test results of the advanced crud separator system was previously investigated. It was suggested that the system characteristics (separation factor) depended on magnetic susceptibility of crud, crud particle diameter and flow rate, and that utilization of the crud size enlarger, a high gradient magnetic system, was effective especially in the lower separation factor region. After the out-of-pile test, the system was shipped to the HBWR (Norway), and the final in-pile test was carried out under the operating conditions similar to BWR. As the test results, the separation factor decreased with increasing inlet crud concentration in the lower inlet concentration region, and crud production (or release) rate and crud separation rate seem to reach the state of equilibrium at the inlet iron concentration approximately 6 ppb for this system size. It was also suggested that separation factor became higher when coolant temperature increased. (author)

  1. Stress wave propagation in reinforced concrete piles during driving

    NARCIS (Netherlands)

    Zorn, N.F.

    1983-01-01

    The aim of this report is to give an insight into what happens in a reinforced concrete pile during driving, and to contribute to design requirements for the loading case pile driving. Since the behaviour of stress waves in piles is influenced by a various number of parameters, the fewest of which r

  2. Test Procedure for Axially Loaded Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    The test procedure described in the following is used when examining the effects of static or cyclic loading on the skin friction of an axially loaded pile in dense sand. The pile specimen is only loaded in tension to avoid any contribution from the base resistance. The pile dimensions are chosen...

  3. 30 CFR 77.215-3 - Refuse piles: certification.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles: certification. 77.215-3 Section... COAL MINES Surface Installations § 77.215-3 Refuse piles: certification. (a) Within 180 days following written notification by the District Manager that a refuse pile can present a hazard, the person...

  4. 30 CFR 77.215-1 - Refuse piles; identification.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; identification. 77.215-1 Section... COAL MINES Surface Installations § 77.215-1 Refuse piles; identification. A permanent identification marker, at least six feet high and showing the refuse pile identification number as assigned by...

  5. 30 CFR 77.215-2 - Refuse piles; reporting requirements.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; reporting requirements. 77.215-2... COAL MINES Surface Installations § 77.215-2 Refuse piles; reporting requirements. (a) The proposed location of a new refuse pile shall be reported to and acknowledged in writing by the District...

  6. 30 CFR 77.215 - Refuse piles; construction requirements.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; construction requirements. 77.215... COAL MINES Surface Installations § 77.215 Refuse piles; construction requirements. (a) Refuse deposited on a pile shall be spread in layers and compacted in such a manner so as to minimize the flow of...

  7. 30 CFR 77.209 - Surge and storage piles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Surge and storage piles. 77.209 Section 77.209... Installations § 77.209 Surge and storage piles. No person shall be permitted to walk or stand immediately above a reclaiming area or in any other area at or near a surge or storage pile where the...

  8. Regional futures: British Columbia

    International Nuclear Information System (INIS)

    Two paradigms that are the source of present-day economic development policies are described. The dominant paradigm is the expansionist world view that assumes economic growth is essentially unlimited, subject to certain constraints, and that the best way to monitor the human economy is through money flows. The steady-state or ecological world view assumes there are real constraints on material throughput and growth, and puts a significant emphasis on natural capital as a form of wealth which is distinct from economic or manufactured capital. Over the long term, each generation must receive from the previous generation at least an adequate stock of natural capital assets to ensure long-term sustainability. For every major category of consumption, such as food and energy, an ecological footprint can be assigned which represents the land needed to sustain a given pattern of consumption. For the lower mainland of British Columbia, this footprint would be about 22 times the actual land area; for the Netherlands, it would be about 15 times larger than the country itself. On a global basis, only about 1.7 hectares per capita of ecologically productive land is actually available, showing that Canadian material standards would not be sustainable on a global level. The steady-state approach to economic development would involve a local and regional approach from the bottom up, preferring small-scale labor-intensive enterprise. Trade would be limited to trading in real ecological surpluses, and value-added products would be made locally instead of shipping raw materials for processing elsewhere. 5 figs

  9. Experimental Evaluation of the Surface Alteration of Gasket Samples under Operative Conditions

    Directory of Open Access Journals (Sweden)

    M.C. Bignozzi

    2015-12-01

    Full Text Available This paper investigates the surface alteration of gasket samples commercialized by two alternative producers. These gaskets, in polymeric materials, are installed in process plants used for cleaning tires molds by a pioneering ultrasonic process. They are exposed to a combination of ultrasonic waves, temperature, humidity and acid attack causing several erosion phenomena. Their surface degradation under ordinary operative conditions was investigated using mechanical and tribological tests. The experimental characterization was performed by optical microscopy, scanning electron microscopy, thermograms, differential scanning calorimetry curves and infrared spectra aiming at defining the specific mechanics of wearing. As a conclusion, it was possible to state that even if samples exhibit similar chemical structures, their thermal and mechanical properties as well as their geometric dimensions are different. Such differences in the materials might cause various unexpected wear behaviors when gaskets are employed in the same working conditions.


  10. Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results

    Directory of Open Access Journals (Sweden)

    Tor A. Johansen

    2004-01-01

    Full Text Available A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerged vessel with a moonpool shows that wave synchronization leads to significant improvements in performance. Depending on the sea state and payload, the results indicate that the reduction in the standard deviation of the wire tension may be up to 50

  11. Reduction in Rebound of Concrete Piles Driven into Clays by Coating Pile Surface with Titanium Dioxide Nanoparticles

    OpenAIRE

    Amalia, Nadya; Asri, Asifa; Rokhmat, Mamat; Sutisna; Abdullah, Mikrajuddin

    2015-01-01

    Using a model for concrete piles driven into clays, we compared penetration depths between uncoated piles and piles coated with titanium dioxide (TiO2) nanoparticles. The behavior of surfaces coated with TiO2 changes to superhydrophilic, enabling water molecules to penetrate inside the clay pores. The attraction suppresses or reduces the compression of water inside the clay pores. The absence of bulk pressure from water causes the pile not to bounce (backward movement after striking). Contrar...

  12. Experimental and Sampling Design for the INL-2 Sample Collection Operational Test

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.; Amidan, Brett G.; Matzke, Brett D.

    2009-02-16

    This report describes the experimental and sampling design developed to assess sampling approaches and methods for detecting contamination in a building and clearing the building for use after decontamination. An Idaho National Laboratory (INL) building will be contaminated with BG (Bacillus globigii, renamed Bacillus atrophaeus), a simulant for Bacillus anthracis (BA). The contamination, sampling, decontamination, and re-sampling will occur per the experimental and sampling design. This INL-2 Sample Collection Operational Test is being planned by the Validated Sampling Plan Working Group (VSPWG). The primary objectives are: 1) Evaluate judgmental and probabilistic sampling for characterization as well as probabilistic and combined (judgment and probabilistic) sampling approaches for clearance, 2) Conduct these evaluations for gradient contamination (from low or moderate down to absent or undetectable) for different initial concentrations of the contaminant, 3) Explore judgment composite sampling approaches to reduce sample numbers, 4) Collect baseline data to serve as an indication of the actual levels of contamination in the tests. A combined judgmental and random (CJR) approach uses Bayesian methodology to combine judgmental and probabilistic samples to make clearance statements of the form "X% confidence that at least Y% of an area does not contain detectable contamination” (X%/Y% clearance statements). The INL-2 experimental design has five test events, which 1) vary the floor of the INL building on which the contaminant will be released, 2) provide for varying the amount of contaminant released to obtain desired concentration gradients, and 3) investigate overt as well as covert release of contaminants. Desirable contaminant gradients would have moderate to low concentrations of contaminant in rooms near the release point, with concentrations down to zero in other rooms. Such gradients would provide a range of contamination levels to challenge the sampling

  13. Full size testing of sheet pile walls

    NARCIS (Netherlands)

    Kuilen, J.W.G. van de; Linden, M.L.R. van der; Katsma, H.; Stolle, P.

    1996-01-01

    Azobé (Lophira alata) is widely used in timber sheet pile walls in the Netherlands. The boards in these walls are coupled and therefore load-sharing can be expected. A simulation model based on the finite element method DIANA (DIANA, 1992) was developed and load-sharing could be calculated. To check

  14. Modelling Pile Installation Effects: A Numerical Approach

    NARCIS (Netherlands)

    Engin, H.K.

    2013-01-01

    One of the most traditional methods for supporting structures resting on soft soils is the use of piles. They generally work by transferring the loads to deeper soil layers, which can provide sufficient bearing capacity when mobilised. This type of foundations has been commonly used throughout the w

  15. Underwater noise generated by offshore pile driving

    NARCIS (Netherlands)

    Tsouvalas, A.

    2015-01-01

    Anthropogenic noise emission in the marine environment has always been an environmental issue of serious concern. In particular, the noise generated during the installation of foundation piles is considered to be one of the most significant sources of underwater noise pollution. This is mainly attri

  16. On the Modelling of Pile Installation

    NARCIS (Netherlands)

    Dijkstra, J.

    2009-01-01

    This thesis introduces two different types of physical model tests to investigate the stress and density change in the soil during installation of a jacked pile as well as two numerical modelling approaches to model the same process in a finite element code capable of large deformations.

  17. Literature review Quasi-static and Dynamic pile load tests: Primarily report on non-static pile load tests

    NARCIS (Netherlands)

    Huy, N.Q.

    2010-01-01

    Pile testing, which plays an importance role in the field of deep foundation design, is performed by static and non-static methods to provide information about the following issues: (Poulos, 1998) - The ultimate capacity of a single pile. - The load-displacement behavior of a pile. - The performance

  18. Pile – Soil Interaction during Vibratory Sheet Pile Driving : a Full Scale Field Study

    OpenAIRE

    Guillement, Claire

    2013-01-01

    Urban construction sites require strict control of their environmental impact, which, for vibratory sheet pile driving, can include damage to nearby structures due to ground vibrations. However, the lack of knowledge concerning the generation of soil vibrations makes the prediction of ground vibration levels difficult. This MSc. thesis in particular, focuses on a crucial link in the vibration transfer chain: the sheet pile – soil interface, which is also one of the least documented. The aim o...

  19. Understanding operational regimes of closed loop pulsating heat pipes: an experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Khandekar, Sameer; Dollinger, Nicolas; Groll, Manfred

    2003-04-01

    Increasing performance of electronic components is resulting in higher heat flux dissipation. Two-phase passive devices are proven solutions for modern microelectronics thermal management. In this context, heat pipe research is being continuously pursued evolving newer solutions to suit present requirements. Pulsating heat pipes (PHPs), a relatively new and emerging technology is one such field of investigation. The operating mechanism of PHP is not well understood and the present state of the art cannot predict required design parameters for a given task. The aim of research work presented in this paper is to better understand these mechanisms through experimental investigations. Experiments were conducted on a PHP made of copper capillary tube of 2-mm inner diameter. Three different working fluids viz. water, ethanol and R-123 were employed. The PHP was tested in vertical (bottom heat mode) and horizontal orientation. The results strongly demonstrate the effect of input heat flux and volumetric filling ratio of the working fluid on the thermal performance of the device. Important insight into the operational regimes of the device has been gained.

  20. Understanding operational regimes of closed loop pulsating heat pipes: an experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Sameer Khandekar; Dollinger, N.; Groll, M. [Universitaet Stuttgart (Germany). Institut fuer Kernenergetik und Energiesysteme

    2003-04-01

    Increasing performance of electronic components is resulting in higher heat flux dissipation. Two-phase passive devices are proven solutions for modern microelectronics thermal management. In this context, heat pipe research is being continuously pursued evolving newer solutions to suit present requirements. Pulsating heat pipes (PHPs), a relatively new and emerging technology is one such field of investigation. The operating mechanism of PHP is not well understood and the present state of the art cannot predict required design parameters for a given task. The aim of research work presented in this paper is to better understand these mechanisms through experimental investigations. Experiments were conducted on a PHP made of copper capillary tube of 2-mm inner diameter. Three different working fluids viz. water, ethanol and R-123 were employed. The PHP was tested in vertical (bottom heat mode) and horizontal orientation. The results strongly demonstrate the effect of input heat flux and volumetric filling ratio of the working fluid on the thermal performance of the device. Important insight into the operational regimes of the device has been gained. (author)

  1. Concept of operation and preliminary experimental results of the DRDC through-wall SAR system

    Science.gov (United States)

    Sévigny, Pascale; DiFilippo, David J.; Laneve, Tony; Chan, Brigitte; Fournier, Jonathan; Roy, Simon; Ricard, Benoît; Maheux, Jean

    2010-04-01

    Mapping the interior of buildings is of great interest to military forces operating in an urban battlefield. Throughwall radars have the potential of mapping interior room layout, including the location of walls, doors and furniture. They could provide information on the in-wall structure, and detect objects of interest concealed in buildings, such as persons and arms caches. We are proposing to provide further context to the end user by fusing the radar data with LIDAR (Light Detection and Ranging) images of the building exterior. In this paper, we present our system concept of operation, which involves a vehicle driven along a path in front of a building of interest. The vehicle is equipped with both radar and LIDAR systems, as well as a motion compensation unit. We describe our ultra wideband through-wall L-band radar system which uses stretch processing techniques to obtain high range resolution, and synthetic aperture radar (SAR) techniques to achieve good azimuth resolution. We demonstrate its current 2-D capabilities with experimental data, and discuss the current progress in using array processing in elevation to provide a 3-D image. Finally, we show preliminary data fusion of SAR and LIDAR data.

  2. Lawrence Livermore National Laboratory Experimental Test Site (Site 300) Potable Water System Operations Plan

    Energy Technology Data Exchange (ETDEWEB)

    Ocampo, Ruben P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bellah, Wendy [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-03-04

    The existing Lawrence Livermore National Laboratory (LLNL) Site 300 drinking water system operation schematic is shown in Figures 1 and 2 below. The sources of water are from two Site 300 wells (Well #18 and Well #20) and San Francisco Public Utilities Commission (SFPUC) Hetch-Hetchy water through the Thomas shaft pumping station. Currently, Well #20 with 300 gallons per minute (gpm) pump capacity is the primary source of well water used during the months of September through July, while Well #18 with 225 gpm pump capacity is the source of well water for the month of August. The well water is chlorinated using sodium hypochlorite to provide required residual chlorine throughout Site 300. Well water chlorination is covered in the Lawrence Livermore National Laboratory Experimental Test Site (Site 300) Chlorination Plan (“the Chlorination Plan”; LLNL-TR-642903; current version dated August 2013). The third source of water is the SFPUC Hetch-Hetchy Water System through the Thomas shaft facility with a 150 gpm pump capacity. At the Thomas shaft station the pumped water is treated through SFPUC-owned and operated ultraviolet (UV) reactor disinfection units on its way to Site 300. The Thomas Shaft Hetch- Hetchy water line is connected to the Site 300 water system through the line common to Well pumps #18 and #20 at valve box #1.

  3. Thermal mapping and trends of Mars analog materials in sample acquisition operations using experimentation and models

    Science.gov (United States)

    Szwarc, Timothy; Hubbard, Scott

    2014-09-01

    The effects of atmosphere, ambient temperature, and geologic material were studied experimentally and using a computer model to predict the heating undergone by Mars rocks during rover sampling operations. Tests were performed on five well-characterized and/or Mars analog materials: Indiana limestone, Saddleback basalt, kaolinite, travertine, and water ice. Eighteen tests were conducted to 55 mm depth using a Mars Sample Return prototype coring drill, with each sample containing six thermal sensors. A thermal simulation was written to predict the complete thermal profile within each sample during coring and this model was shown to be capable of predicting temperature increases with an average error of about 7%. This model may be used to schedule power levels and periods of rest during actual sample acquisition processes to avoid damaging samples or freezing the bit into icy formations. Maximum rock temperature increase is found to be modeled by a power law incorporating rock and operational parameters. Energy transmission efficiency in coring is found to increase linearly with rock hardness and decrease by 31% at Mars pressure.

  4. Influence of experimental set-up on the infiltration characteristics during managed aquifer recharge operation

    Science.gov (United States)

    Fichtner, Thomas; Vanzella de Melo, Julio Augusto; Stefan, Catalin

    2016-04-01

    The main focus during operation of managed aquifer recharge (MAR) is on clogging processes, specifically on the changes of infiltration capacities and degradation of infiltrated organic substances including vadose zone oxygen dynamics. Lab scale experiments are one opportunity to understand and characterize these processes under different drying and wetting cycles and infiltration rates. However, the multitude of assumptions and scale-related limitations of downscale investigations often lead to over- or underestimations, rendering their results useless when translated to field-like conditions. Therefore, the specific objective of this investigation is to compare the results obtained from two different experimental set-ups with different scales: a 3D, rectangular shaped, stainless steel lysimeter (1.5 x 1.0 x 1.0 m) with an infiltration basin installed in the centre of its surface and a 1D soil column (1m, ᴓ 0.15 m) with the infiltration over the complete column surface. The study focuses on the influence of the experimental setup conditions on the soil clogging, water flow pattern, oxygen dynamics and degradation of organic substances. The results should allow making statements about the suitability of these lab experiments for the investigation of processes taking place in the unsaturated soil zone during operation of MAR. Both experimental units were packed with the same soil and equipped with tensiometers, TDR-probes, oxygen probes and suction cups in two depths for the estimation of spatial and temporal distribution of soil moisture, oxygen and infiltrated substances. The lysimeter and the column were placed inside of a fully automatic climate tent, which facilitates the exact control of air temperature and humidity. The first results confirm that both infiltration units are suitable to simulate the clogging and the oxidation of easily degradable organic substances. However, the velocity of water transport is higher in the column compared with the lysimeter

  5. Experimental fast reactor Joyo emergency operation act in Northeastern Japan Earthquake 3.11

    International Nuclear Information System (INIS)

    Experimental fast reactor 'Joyo' under facility's periodic inspection received damage at its power incoming unit due to the 2011 off the Pacific Coast of Tohoku Earthquake, which incurred loss-of-offsite-power. Immediately, two emergency diesel generators (D/G) automatically started, which supplied emergency system power. During eight days before the power incoming unit got provisional restoration, power supply through D/G continued. During this period, emergency measures for fuel and cooling water securement for D/G were taken, which forced unexperienced long-term load operation for D/G. This paper reports the change of plant conditions of Joyo, as well as the measures taken for keeping fuel and cooling water for continuing the operation of D/G. Since the main machines of the primary system and secondary system were functioning normally after the earthquake, the plant could be maintained in a stable state. As for the fuel for D/G, reduction in fuel consumption based on load suppression was implemented, and the cooperation of trading firms, related facilities, and local suppliers secured the fuel that supported the long-term operation of D/G. As for the cooling water, the cooperation of a self-defense fire brigade allowed to secure the required amount by utilizing the reserved water in the water tank for fire prevention. From these series of experiences of handling the plant, it was possible to extract the future challenges against the time when a massive earthquake or prolonged power failure has occurred. (A.O.)

  6. NONLINEAR DYNAMICAL CHARACTERISTICS OF PILES UNDER HORIZONTAL VIBRATION

    Institute of Scientific and Technical Information of China (English)

    HU Yu-jia; CHENG Chang-jun; YANG Xiao

    2005-01-01

    The pile-soil system is regarded as a visco-elastic half-space embedded pile. Based on the method of continuum mechanics, a nonlinear mathematical model of pilesoil interaction was established-a coupling nonlinear boundary value problem. Under the case of horizontal vibration, the nonlinearly dynamical characteristics of pile applying the axis force were studied in horizontal direction in frequency domain. The effects of parameters, especially the axis force on the stiffness were studied in detail. The numerical results suggest that it is possible that the pile applying an axis force will lose its stability. So, the effect of the axis force on the pile is considered.

  7. The Settlement Behavior of Piled Raft Interaction in Undrained Soil

    DEFF Research Database (Denmark)

    Ghalesari, Abbasali Taghavi; Barari, Amin; Amini, Pedram Fardad;

    2013-01-01

    , the behavior of a piled raft on undrained soil is studied based on a series of parametric studies on the average and differential settlement of piled raft using three-dimensional finite element analysis. The settlement behavior is found to be dependent on the number of piles and raft thickness.......Offshore piled raft foundations are one of the most commonly used foundations in offshore structures. When a raft foundation alone does not satisfy the design requirements, the addition of piles may improve both the ultimate load capacity and the settlement performance of the raft. In this paper...

  8. Seismic Response Analysis of Portal Water Injection Sheet Pile

    Institute of Scientific and Technical Information of China (English)

    WANG Yuanbin; GUO Haiyan; ZHANG Chunhui

    2007-01-01

    To further the study on the newly developed portal water injection sheet pile under static loads, in this paper, by adopting the nonlinear calculation module of FEM software ANSYS, a model for the interaction between the soil and the sheet piles is set up,and the seismic response analysis for this type of space-retaining structure is performed. The effects of the embedded depth and the distance between the front pile and the back pile on the dynamic characteristics of the portal water injection sheet pile are studied.

  9. In-Pile Thermal Conductivity Measurement Method for Nuclear Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Joy L. Rempe; Brandon Fox; Heng Ban; Joshua E. Daw; Darrell L. Knudson; Keith G. Condie

    2009-08-01

    Thermophysical properties of advanced nuclear fuels and materials during irradiation must be known prior to their use in existing, advanced, or next generation reactors. Thermal conductivity is one of the most important properties for predicting fuel and material performance. A joint Utah State University (USU) / Idaho National Laboratory (INL) project, which is being conducted with assistance from the Institute for Energy Technology at the Norway Halden Reactor Project, is investigating in-pile fuel thermal conductivity measurement methods. This paper focuses on one of these methods – a multiple thermocouple method. This two-thermocouple method uses a surrogate fuel rod with Joule heating to simulate volumetric heat generation to gain insights about in-pile detection of thermal conductivity. Preliminary results indicated that this method can measure thermal conductivity over a specific temperature range. This paper reports the thermal conductivity values obtained by this technique and compares these values with thermal property data obtained from standard thermal property measurement techniques available at INL’s High Test Temperature Laboratory. Experimental results and material properties data are also compared to finite element analysis results.

  10. Numerical analysis of kinematic soil—pile interaction

    Science.gov (United States)

    Castelli, Francesco; Maugeri, Michele; Mylonakis, George

    2008-07-01

    In the present study, the response of singles pile to kinematic seismic loading is investigated using the computer program SAP2000@. The objectives of the study are: (1) to develop a numerical model that can realistically simulate kinematic soil-structure interaction for piles accounting for discontinuity conditions at the pile-soil interface, energy dissipation and wave propagation; (2) to use the model for evaluating kinematic interaction effects on pile response as function of input ground motion; and (3) to present a case study in which theoretical predictions are compared with results obtained from other formulations. To evaluate the effects of kinematic loading, the responses of both the free-field soil (with no piles) and the pile were compared. Time history and static pushover analyses were conducted to estimate the displacement and kinematic pile bending under seismic loadings.

  11. Friction effects on lateral loading behavior of rigid piles

    DEFF Research Database (Denmark)

    Zania, Varvara; Hededal, Ole

    2012-01-01

    The adequacy of the p -y curves used in the current practice for the design of rigid pile foundations with large diameter, like in the case of monopile foundations of offshore wind turbines, has been widely questioned. The current study aims at analyzing the lateral behavior of rigid piles, while...... taking into account the shear frictional resistance along the pile. For this purpose efficient three dimensional finite element models of different diameter have been developed. The increase of the side friction and of the diameter of the pile is shown to alter the failure pattern and increase...... the lateral capacity of the pile. The obtained p - y curves demonstrate the importance of the aforementioned parameters in the design of rigid piles, as the reduction of friction along the interface reduces not only the ultimate load but also the stiffness of the soil-pile response. Read More: http...

  12. The characterization of Vicker's microhardness indentations and pile-up profiles as a strain-hardening microprobe

    International Nuclear Information System (INIS)

    Microhardness measurements have long been used to examine strength properties and changes in strength properties in metals, for example, as induced by irradiation. Microhardness affords a relatively simple test that can be applied to very small volumes of material. Microhardness is nominally related to the flow stress of the material at a fixed level of plastic strain. Further, the geometry of the pile-up of material around the indentation is related to the strain-hardening behavior of a material; steeper pile-ups correspond to smaller strain-hardening rates. In this study the relationship between pile-up profiles and strain hardening is examined using both experimental and analytical methods. Vickers microhardness tests have been performed on a variety of metal alloys including low alloy, high Cr and austenitic stainless steels. The pile-up topology around the indentations has been quantified using confocal microscopy techniques. In addition, the indentation and pile-up geometry has been simulated using finite element method techniques. These results have been used to develop an improved quantification of the relationship between the pile-up geometry and the strain-hardening constitutive behavior of the test material

  13. The Strength of Rubble Pile Asteroids

    Science.gov (United States)

    Scheeres, D. J.; Sanchez, P.

    2012-12-01

    The rubble pile hypothesis for small asteroids in the Near Earth and Main Belt populations have been driven by several factors, including the observed high porosity of those bodies whose mass have been measured, the evident limitation on spin rate of asteroids larger than ~500 meters, and direct observation of the surface morphology of these bodies. Given these observations, it has been presumed that small asteroids should evolve as if they were cohesionless collections of grains. Detailed geophysical analysis of these bodies by Holsapple (Icarus 2010) show that cohesionless bodies will evolve under the addition of angular momentum by the YORP effect into more distended and, paradoxically, more slowly rotating bodies. Additional analysis in Holsapple (Icarus 2007) has shown that cohesional strength within a rubble pile could strengthen a collection of grains to the point where they could sustain rapid rotation. In our current talk we use the above as a starting point and incorporate new observations of the asteroid morphology driven by recent analysis of asteroid Itokawa by the Hayabusa science team and research on the mechanics of grains in the space environment (Scheeres et al. 2010). Analysis of images of Itokawa determined a measured size distribution of 1/d^3 for larger grains on asteroid Itokawa (Michikami et al., Earth Planets Space, 60, 13-20, 2008). Analysis of the sample shows the presence of micron sized dust on that asteroid's surface (Tsuchiyama et al., Science 333, 1125, 2011). Combining these observations provides a global indication of grain distribution within rubble piles. Even assuming a less steep distribution of 1/d^2 for dust grains smaller than 1 mm in size, the interior of Itokawa should still be dominated by the finest dust grains, with the mean grain size equal to ~ twice the smallest grain in the distribution. One implication of this result is that fines are present on the surface of the rubble pile Itokawa and thus should be distributed

  14. Auditing the British Medical Journal.

    OpenAIRE

    Channer, K S

    1994-01-01

    The purpose of this study was to audit the outcome in terms of change in practice of the published research from one volume of the British Medical Journal. All original papers and short reports from one Volume 296 of the British Medical Journal (BMJ) 1988 were read and classified into theoretical only, practical and theoretical and practical. Those papers with any practical message were reviewed by one of a panel of specialists in the subject of the paper to assess if the recommendation made ...

  15. A computational model of pile vertical vibration in saturated soil based on the radial disturbed zone of pile driving

    Science.gov (United States)

    Li, Qiang; Shi, Qian; Wang, Kuihua

    2010-06-01

    In this study, a simplified computational model of pile vertical vibration was developed. The model was based on the inhomogeneous radial disturbed zone of soil in the vicinity of a pile disturbed by pile driving. The model contained two regions: the disturbed zone, which was located in the immediate vicinity of the pile, and the undisturbed region, external to the disturbed zone. In the model, excess pore pressure in the disturbed zone caused by pile driving was assumed to follow a logarithmic distribution. The relationships of stress and strain in the disturbed zone were based on the principle of effective stress under plain strain conditions. The external zone was governed by the poroelastic theory proposed by Biot. With the use of a variable separation method, an analytical solution in the frequency domain was obtained. Furthermore, a semi-analytical solution was attained by employing a numerical convolution method. Numerical results from the frequency and time domain indicated that the equivalent radius of the disturbed zone and the ratio of excess pore pressure had a significant effect on pile dynamic response. However, actual interactions between pile and soil will be weaker due to the presence of the radial disturbed zone, which is caused by pile driving. Consequently, the ideal undisturbed model overestimates the interaction between pile and soil; however, the proposed model reflects the interaction of pile and soil better than the perfect contact model. Numerical results indicate that the model can account for the time effect of pile dynamic tests.

  16. The mechanical response of piles with consideration of pile-soil interactions under a periodic wave pressure

    Institute of Scientific and Technical Information of China (English)

    朱峰; 徐卫亚; 王环玲

    2014-01-01

    The pile-soil interaction under wave loads is an extremely complex and difficult issue in engineering. In this study, a physical model test is designed based on the principle of the gravity similarity to obtain time histories of wave forces of unsteady regular waves, and to measure the magnitude and the distribution of wave forces acting on the piles. A numerical model and relevant numerical methods for the pile-soil contact surface are adopted based on the principles of elastic dynamics. For a practical project, the time histories of wave forces on the piles are obtained through physical model tests. The deformations of the piles in the pile-soil interactions and the distribution of the bending moment on the piles are studied. It is shown that, with the increase of the period of wave pressures, the absolute value of the horizontal displacement of the piles increases, the embedment depth of the piles increases, and the scope of influence of soils increases. The change of the bending moment on the piles is consistent with that of its theoretical results, and the proposed numerical method can very well simulate the properties of the piles.

  17. Experimental study of combustion noise radiation during transient turbocharged diesel engine operation

    International Nuclear Information System (INIS)

    Diesel engine noise radiation has drawn increased attention in recent years since it is associated with the passengers' and pedestrians' discomfort, a fact that has been acknowledged by the manufacturers and the legislation in many countries. In the current study, experimental tests were conducted on a truck, turbocharged diesel engine in order to investigate the mechanism of combustion noise emission under various transient schedules experienced during daily driving conditions, namely acceleration and load increase. To this aim, a fully instrumented test bed was set up in order to capture the development of key engine and turbocharger variables during the transient events. Analytical diagrams are provided to explain the behavior of combustion noise radiation in conjunction with cylinder pressure (spectrum), turbocharger and governor/fuel pump response. Turbocharger lag was found to be the main cause for the noise spikes during all test cases examined, with the engine injection timing calibration and the slow adjustment of cylinder wall temperature to the new fueling conditions playing a vital role. The analysis was extended with a quasi-steady approximation of transient combustion noise using steady-state maps, in order to better highlight the effect of dynamic engine operation on combustion noise emissions. -- Highlights: → Studying the effects of acceleration and load increase on the combustion noise radiation from a turbocharged diesel engine. → Turbocharger lag was the most notable contributor for the behavior of combustion noise radiation. → Turbocharged diesel engine behaves noisier at acceleration compared with the steady-state operation. → Fuel limiter, governing and engine injection timing calibration play a decisive role on the emission of combustion noise. → Transient noise radiation was smoothed the slower the acceleration and the smaller the demanded speed increase.

  18. Model study on dynamic behavior of a single pile-soil interaction in surface layer. Kogata mokei jikken ni yoru kui-jiban no doteki sogo sayos seijo no kosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yahata, K. (Kajima Corp., Tokyo (Japan))

    1993-10-31

    An experimental study was made on the dynamic interaction between pile and soil by a small scale model made of silicone rubber. The model consists of models of ground, friction pile, and supporting pile. The vibration experiment was carried out in two ways, i.e., the pile head excitation by an exciter and the excitation by a vibration desk. The input was a steady excitation. The excitation from the exciter was transmitted to the pile head through the rigid rod which was supported horizontally. Although it is difficult to obtain the linear result in the horizontal excitation experiment in a single pile on the real ground, this experiment gave the linear results to be compared with the analytical results. The response of pile was influenced by the dynamic characteristic of the ground. In some cases, the influence was enhanced at the resonance point of the surface ground. The pile length dependence of the horizontal rigidity was not so big. The experimental results quite agreed with the results of the pile and ground interaction which were calculated based on the three-dimensional wave theory. The experiments using exciter and the vibrator clarified the nature of the dynamic interaction. 4 refs., 10 figs.

  19. Experimental study of one-stage VM cryocooler operating below 8 K

    Science.gov (United States)

    Pan, Changzhao; Zhang, Tong; Zhou, Yuan; Wang, Junjie

    2015-12-01

    The Vuilleumier (VM) refrigerator, known as heat driven refrigerator, is one kind of closed-cycle Stirling type regenerative refrigerator. The VM refrigerator with power being supplied by liquid nitrogen was proposed by Hogen and developed by Zhou, which shows great potential for development below 10 K. This paper describes the experimental development of a VM cryocooler operating below 8 K, which was achieved by using liquid nitrogen as a heat sink of middle cavity. The regenerator was optimized by using a part of metallic magnetic regenerator material Er3Ni to replace the lead sphere and a no-load temperature of 7.8 K was obtained. Then all the lead spheres were replaced by Er0.6Pr0.4 material and a no-load temperature of 7.35 K was obtained, which is the lowest temperature for this kind of refrigerator reported so far. The cooling power at 10 K is about 500 mW with a pressure ratio near 1.6 and a charge pressure of 1.8 MPa. Especially, the magnetic material Er0.6Pr0.4 was found to be a potential substitution for the conventional lead.

  20. In pile helium loop ''COMEDIE''

    International Nuclear Information System (INIS)

    The SR1 test in the COMEDIE loop has permitted to demonstrate particularly the device operation reliability with a fuel loading. The post-irradiation examinations have pointed out the good filter efficiency and have enabled to determine the deposition profiles either for the activation products (e.g.: 51Cr, 60Co) or for the fission products (e.g.: sup(110m)Ag, 131I, 134Cs, 137Cs). (author)

  1. 不同运动方向两桩间桩-土-桩相互作用%PILE-SOIL-PILE INTERACTION BETWEEN TWO PILES MOVING ALONG DIFFERENT DIRECTIONS

    Institute of Scientific and Technical Information of China (English)

    孔令刚; 樊继营; 陈仁朋; 陈云敏

    2013-01-01

    Both centrifuge modeling and numerical simulation are employed to investigate pile-soil-pile interaction between two adjacent piles with pile spacing of 3 times pile diameter moving in different directions. The influence of pile spacing,internal friction angle of sand,and different displacements of the leading and trailing piles on reduction factor are also analyzed based on numerical results. It is found that pile-soil-pile interaction is significant in two adjacent piles undergoing different movement directions. The reduction factor of the trail pile is not larger than that of the leading one in the investigated two cases. It is also found that reduction factors for the leading and trail piles almost linearly increase as pile spacing varies from 3 times pile diameter to 5 times and almost keep constant with internal friction angle. In addition,loading mode has certain effect on reduction factors of the two piles.%通过离心模型试验和数值模拟手段研究不同运动方向下桩间距为3倍桩径的两桩间相互作用规律,并分析桩间距、土体内摩擦角以及不同桩头位移对前、后桩折减系数的影响。通过分析表明,沿不同方向运动的两桩间存在明显的桩-土-桩相互作用,该相互作用效果与桩所在位置有明显关系,前桩的相互作用折减系数明显大于于后桩;当桩间距在3~5倍桩径范围内,前、后桩折减系数随桩间距近似线性变化;砂土内摩察角对折减系数的影响可以忽略。另外,不同加载方式对两桩的折减系数也有一定影响。

  2. British Industrial Libraries Before 1939

    Science.gov (United States)

    Marshall, Margaret R.

    1972-01-01

    British industrial firm libraries are traced from their beginnings till 1939, by which date they had spread to many branches of industry and had been recognized as an important part of the industrial and library worlds, thus establishing standard patterns of work. The origins and significance of Aslib are discussed. (27 references) (Author/NH)

  3. Young British Art / Hanno Soans

    Index Scriptorium Estoniae

    Soans, Hanno, 1974-

    2001-01-01

    1990ndate kunsti muutumisest. Inglise kunstniku Peter Daviese maalist "Kuum esimene sada" (1996), Gavin Turki vahakujuna valminud autoportreest "Pop". "Young British Art'i" uuskunstist ja Jasper Zoova installatsioonist "F1". Eri analüüsivõimalusi pakkuvatest töödest (Marko Laimre & Ene-Liis Semperi 2000. a. novembri ühisnäituse osa töid).

  4. Are cometary nuclei primordial rubble piles?

    Science.gov (United States)

    Weissman, P. R.

    1986-01-01

    Whipple's icy conglomerate model for the cometary nucleus has had considerable sucess in explaining a variety of cometary phenomena such as gas production rates and nongravitational forces. However, as discussed here, both observational evidence and theoretical considerations suggest that the cometary nucleus may not be a well-consolidated single body, but may instead be a loosely bound agglomeration of smaller fragments, weakly bonded and subject to occasional or even frequent disruptive events. The proposed model is analogous to the 'rubble pile' model suggested for the larger main-belt asteroids, although the larger cometary fragments are expected to be primordial condensations rather than collisionally derived debris as in the asteroid case. The concept of cometary nuclei as primordial rubble piles is proposed as a modification of the basic Whipple model, not as a replacement for it.

  5. Soil Structure Interaction in Energy Piles

    OpenAIRE

    Chen, Diming

    2016-01-01

    This study focuses on developing an improved thermo-mechanical soil-structure interaction (i.e., load transfer) analysis to assess the axial strains, stresses, and displacements during thermo-mechanical loading of energy piles in different soils having different end restraint boundary conditions. This study builds on established analyses by (i) incorporating an algorithm to identify the location of the point of zero displacement (i.e., the null point) during changes in temperature, (ii) addin...

  6. Underwater noise generated by offshore pile driving

    OpenAIRE

    Tsouvalas, A.

    2015-01-01

    Anthropogenic noise emission in the marine environment has always been an environmental issue of serious concern. In particular, the noise generated during the installation of foundation piles is considered to be one of the most significant sources of underwater noise pollution. This is mainly attributed to the recent developments in the offshore wind industry. To meet the increasing demand for energy from renewable resources, a large number of offshore wind farms are planned to be constructe...

  7. Full Wave Solution for Hydrodynamic Behaviors of Pile Breakwater

    Institute of Scientific and Technical Information of China (English)

    ZHU Da-tong

    2013-01-01

    Rayleigh expansion is used to study the water-wave interaction with a row of pile breakwater in finite water depth.Evanescent waves,the wave energy dissipated on the fluid resistance and the thickness of the breakwater are totally included in the model.The formulae of wave reflection and transmission coefficients are obtained.The accuracy of the present model is verified by a comparison with existing results.It is found that the predicted wave reflection and transmission coefficients for the zero order are all highly consistent with the experimental data (Hagiwara,1984;Isaacson et al.,1998) and plane wave solutions (Zhu,2011).The losses of the wave energy for the fluid passing through slits play an important role,which removes the phenomena of enhanced wave transmission.

  8. Effect of Rigidity of Plinth Beam on Soil Interaction of Modeled Building Frame Supported on Pile Groups

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Reddy, C.

    2014-01-01

    Full Text Available This paper presents the effect of rigidity of plinth beam on a model building frame supported by pile groups embedded in cohesionless soil (sand through the results of static vertical load tests. The effect of rigidity of plinth beam on displacements and rotation at the column base and also shears and bending moments in the building frame were investigated. In the analytical model, soil nonlinearity in the axial direction is characterized by nonlinear vertical springs along the length of the pile (t-z curves and at the tip of the pile (Q-z curves while in the lateral direction by the p-y curves. Results revealed that, shear force and bending moment values which were back calculated from the experimental results, showed considerable reduction with the reduction of the rigidity of the plinth beam. The response of the frame from the experimental results is in good agreement with that obtained by the nonlinear finite element analysis.

  9. Soil Plug Effect Prediction and Pile Driveability Analysis for Large-Diameter Steel Piles in Ocean Engineering

    Institute of Scientific and Technical Information of China (English)

    LIU Run; YAN Shu-wang; LI Zhi-hua

    2009-01-01

    Long steel piles with large diameters have been more widely used in the field of ocean engineering.Owing to the pile with a large diameter,soil plug development during pile driving has great influences on pile driveability and beating capacity.The response of soil plug developed inside the open-ended pipe pile during the dynamic condition of pile-driving is different from the response under the static condition of loading during service.This paper addresses the former aspect.A numerical procedure for soil plng effect prediction and pile driveability analysis is proposed and described.By taking into consideration of the pile dimension effect on side and tip resistance,this approach introduces a dimensional coefficient to the conventional static equilibrium equations for the plug differential unit and proposes an improved static equity method for the plug effect prediction.At the same time,this approach introduces a simplified model by use of one-dimensional stress wave equation to simulate the interaction between soft ping and pile inner wall.The proposed approach has been applied in practical engineering analyses.Results show that the calculated plug effect and pile driveability based on the proposed approach agree well with the observed data.

  10. 19 January 2011 - British University of Manchester, Vice-President and Dean for the Faculty of Engineering and Physical Sciences Professor of Structural Engineering School of Mechanical, Aerospace and Civil Engineering C. Bailey in CERN Control Centre with Department Head P. Collier; at LHCb with R. Lindner and ATLAS underground experimental area with Deputy Spokesperson D. Charlton, througout accompanied by . Collier with R. Appleby and F. Loebinger

    CERN Multimedia

    Maximilien Brice

    2011-01-01

    19 January 2011 - British University of Manchester, Vice-President and Dean for the Faculty of Engineering and Physical Sciences Professor of Structural Engineering School of Mechanical, Aerospace and Civil Engineering C. Bailey in CERN Control Centre with Department Head P. Collier; at LHCb with R. Lindner and ATLAS underground experimental area with Deputy Spokesperson D. Charlton, througout accompanied by . Collier with R. Appleby and F. Loebinger

  11. Impedance function of a group of vertical piles

    International Nuclear Information System (INIS)

    Impedance and transfer functions of a group of vertical piles located in any desired configuration in plan in a horizontally stratified soil layer are derived. Hysteretic and radiation damping are accounted for. The method separates the piles and the soil, introducing unknown interaction forces. The total flexibility matrix of the soil is constructed, superposing the (complex) flexibility coefficients caused by the interaction forces of a single pile only. The dependence of the impedance and transfer functions on the oscllating frequency for foundations with different numbers of piles is investigated. Pile-soil-pile interaction is shown to be very important for all modes of vibration. The procedure is used in the seismic analysis of a reactor building. (Author)

  12. Vertical bearing capacity of pile based on load transfer model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ming-hua; YANG Ming-hui; ZOU Xin-jun

    2005-01-01

    The load transfer analytical method is applied to study the bearing mechanism of piles with vertical load in this paper. According to the different hardening rules of soil or rock around the pile shaft, such as work-softening, ideal elasto-plastic and work-hardening, a universal tri-linear load transfer model is suggested for the development of side and tip resistance by various types of soil (rock) with the consideration of sediment at the bottom of the pile. Based on the model, a formula is derived for the relationship between the settlement and load on the pile top to determine the vertical bearing capacity, taking into account such factors as the characteristics of the stratum, the side resistance along the shaft, and tip resistance under the pile tip. A close agreement of the calculated results with the measured data from a field test pile lends confidence to the future application of the present approach in engineering practice.

  13. SCOUR MITIGATION AT BRIDGE PIERS USING SACRIFICIAL PILES

    Institute of Scientific and Technical Information of China (English)

    M. Anisul HAQUE; Md. Munsur RAHMAN; G.M. Tarekul ISLAM; M. Asad HUSSAIN

    2007-01-01

    To mitigate scour around bridge piers, sacrificial piles are economic method where natural processes are involved. The arrangement should be such that scoured materials from the sacrificial piles should have enough volume to fill the scour hole created upstream of the pier in such a way that sediments are trapped inside the scour hole. This concept differs from earlier study made with sacrificial piles that mainly deals to reduce the strength of horseshoe vortex. To determine the effect of sacrificial piles for scour mitigation, alternative arrangements of piles were tested in front of a rectangular pier under clear-water condition and found that when the group of piles is placed at a distance of twice the projected width of the pier, for which percentage of blockage of the pier width is 60%, the scour volume can be reduced upto 61% while the maximum scour depth can be reduced upto 50%.

  14. Settlement calculation for long-short composite piled raft foundation

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ming-hua; ZHANG Ling; YANG Ming-hui

    2006-01-01

    The mechanism of long-short composite piled raft foundation was discussed. Assuming the relationship between shear stress and shear strain of the surrounding soil was elasto-plastic, shear displacement method was employed to establish the different explicit relational equations between the load and the displacement at the top of pile in either elastic or elasto-plastic period. Then Mylonakis & Gazetas model was introduced to simulate the interaction between two piles or between piles and soil. Considering the effect of cushion, the flexible coefficients of interaction were provided. With the addition of a relevant program, the settlement calculation for long-short composite piled raft foundation was developed which could be used to account for the interaction of piles,soil and cushion. Finally, the calculation method was used to analyze an engineering example. The calculated value of settlement is 10.2 mm, which is close to the observed value 8.8 mm.

  15. Separation of British Gas' transportation and storage business

    International Nuclear Information System (INIS)

    In making his substantive reference of the transportation and storage business of British Gas to the Monopolies and Mergers Commission, the Director General of Gas Supply identified the following principal effects adverse to the public interest: ''The absence of provision for the establishment of an independent undertaking to operate the pipe-line system and other facilities used by British Gas for the conveyance and storage of gas which would not be subject to conflicting interests in securing (a) transparency of the prices charged, the costs incurred and the operating methods in respect of the conveyance and storage of gas; (b) proper allocation to various parts of the Gas Supply Business of costs incurred and returns by that business; and (c) protection of information relating to the conveyance and storage of gas from which British Gas might obtain unfair commercial advantage, and thereby avoid the restriction or distortion of competition between British Gas and other persons whose business consists of or includes the supply of gas''. This paper considers the structural issues associated with achieving effective competition and looks at how the relationship between the businesses of supply and transportation might be organised in the short and longer term. (Author)

  16. In-Pile Thermal Conductivity Measurement Methods for Nuclear Fuels

    OpenAIRE

    Fox, Brandon S.

    2010-01-01

    Measuring nuclear fuel thermal conductivity in-pile can provide much needed data for understanding fuel performance during irradiation and yield thermophysical property data needed for simulation codes and fuel databases. The objective of this research is to develop and compare two in-pile thermal conductivity methods in a laboratory setting using surrogate fuel materials. A steady-state radial heat flow method was investigated to understand its viability as an in-pile steady-state thermal...

  17. Influence of heave reducing piles on ground movements around excavations

    OpenAIRE

    McNamara, A M

    2001-01-01

    The research concerns the influence of piles, installed beneath deep excavations, as a means of reducing movements in the surrounding ground. The work focussed on the use of piles installed as a part of top down basement construction, a technique used in conjunction with deep excavations in urban areas. The investigations sought to explore the effectiveness of bored piles as a means of enhancing the stiffness of the soil beneath the excavation and so reducing the spread of movements to the su...

  18. Assessment of Time Functions for Piles Driven in Clay

    DEFF Research Database (Denmark)

    Augustesen, Anders; Andersen, Lars; Sørensen, Carsten Steen

    The vertical bearing capacity of piles situated in clay is studied with regard to the long-term set-up. A statistical analysis is carried out on the basis of data from numerous static loading tests. The database covers a wide range of both soil and pile properties, which ensures a general....... Hence, it is suggested that a constant set-up factor should be applied for the prediction of pile capacities at a given time after initial driving....

  19. Experimental implementation of encoded logical qubit operations in a perfect quantum error correcting code.

    Science.gov (United States)

    Zhang, Jingfu; Laflamme, Raymond; Suter, Dieter

    2012-09-01

    Large-scale universal quantum computing requires the implementation of quantum error correction (QEC). While the implementation of QEC has already been demonstrated for quantum memories, reliable quantum computing requires also the application of nontrivial logical gate operations to the encoded qubits. Here, we present examples of such operations by implementing, in addition to the identity operation, the NOT and the Hadamard gate to a logical qubit encoded in a five qubit system that allows correction of arbitrary single-qubit errors. We perform quantum process tomography of the encoded gate operations, demonstrate the successful correction of all possible single-qubit errors, and measure the fidelity of the encoded logical gate operations.

  20. Vertical Dynamic Impedance of Tapered Pile considering Compacting Effect

    Directory of Open Access Journals (Sweden)

    Wenbing Wu

    2013-01-01

    Full Text Available Based on complex stiffness transfer model, the vertical vibration of tapered pile embedded in layered soil is theoretically investigated by considering the compacting effect of the soil layer surrounding the tapered pile in the piling process. Allowing for the stratification of the surrounding soil and variable crosssection of the tapered pile, the pile-soil system is discretized into finite segments. By virtue of the complex stiffness transfer model to simulate the compacting effect, the complex stiffness of different soil segments surrounding the tapered pile is obtained. Then, substituting the complex stiffness into the vertical dynamic governing equation of tapered pile, the analytical solution of vertical dynamic impedance of tapered pile under vertical exciting force is derived by means of the Laplace technique and impedance function transfer method. Based on the presented solutions, the influence of compacting effect of surrounding soil on vertical dynamic impedance at the pile head is investigated within the low frequency range concerned in the design of dynamic foundation.

  1. Simulation of Pile-up in the ATLAS Experiment

    CERN Document Server

    Marshall, Z; The ATLAS collaboration

    2014-01-01

    The high luminosity of the LHC results in a significant background to interesting physics events known as pile-up. ATLAS has adopted two independent methods for modeling pile-up and its effect on analyses. The first is a bottom-up approach, using a detailed simulation of the detector to recreate each component of the pile-up background. The second uses specially recorded data events to emulate it. This article reports on the experience using both of these methods, including performance considerations, for simulating pile-up in ATLAS.

  2. Soil-cement piles by drilling-mixing method

    OpenAIRE

    ZOTSENKO N.; VYNNYKOV YU.; ZOTSENKO V.

    2015-01-01

    Development of the drilling-mixing technology lead to the appearance of the soil-cement piles. It has all advantages of the drilling piles, but it eliminate the problem of the well walls stability. Drilling-mixing technology consist in, that machine with drilling-mixing head loosen soil; impregnated it by laitance; and mixed. Piles are perform from the excavation bottom until design depth. The movable soil-cement mixture feels wells during all the process. Pile has cylindrical form with set s...

  3. Bearing Capacity of Mixed Pile with Stiffness Core

    Institute of Scientific and Technical Information of China (English)

    YUE Jianwei; JIANG Xinliang; LING Guangrong

    2006-01-01

    To study load transfer mechanism and bearing capacity of a mixed pile with stiffness core (MPSC), which is formed by inserting a precast reinforced concrete pile (PRCP), in-situ tests involving MPSCs with different lengths, diameters, water cement ratios and PRCPs, cement mixed piles, and drilling hole piles, were carried out.Limit bearing capacities, load-settlement curves and stress distribution of MPSCs and mixed piles were obtained.The load transfer between cement soil and PRCP was analyzed by finite element method (FEM).Test results and FEM analysis show that an MPSC has fully utilized the big friction from a cement mixed pile and the high compressive strength from a PRCP which transfers outer top load into the inner cement soil, and that inserting a PRCP into a mixed pile changes the stress distribution of a mixed pile and improves frictional resistance between a mixed pile and soil.The length and the section area on PRCP of an MPSC both have an optimum value.Adopting MPSC is effective in improving the bearing capacity of soft soil ground.

  4. Bearing capacity and mechanical behavior of CFG pile composite foundation

    Institute of Scientific and Technical Information of China (English)

    陈秋南; 赵明华; 周国华; 张主华

    2008-01-01

    CFG pile (i.e., pile constructed by granular materials of cement, fly-ash and gravel) composite foundation is applied in subsoil treatment widely and successfully. In order to have a further study of this kind of subsoil treatment technology, the influencing factors and calculation methods of the vertical bearing capacity of single CFG pile and the CFG pile composite foundation were discussed respectively. And based on the obtained solutions, effects by the cushion and measurements to reduce negative friction area were analyzed. Moreover, the developing law of settlement and bearing capacity eigenvalue controlled by the material strength with the increase of load were given for the CFG composite foundation. The in-situ static load test was tested for CFG pile. The results of test show that the maximum test load or half of the ultimate load is used from all the points of test, the average bearing capacity eigenvalue of single pile is 390 kN, and slightly greater than the design value of bearing capacity. The bearing capacity eigenvalues of composite foundation for 3 piles are greater than 300 kPa, and the mechanical properties of CFG pile composite foundation are almost identical in the case of the same load and cushion thickness. The pile-soil stress ratio and the load-sharing ratio can be adjusted through setting up cushion thickness.

  5. The experimental setup of a large field operational test for cooperative driving vehicles at the A270

    NARCIS (Netherlands)

    Broek, T.H.A. van den; Netten, B.D.; Hoedemaeker, M.; Ploeg, J.

    2010-01-01

    In this paper, a large field operational test (FOT) for cooperative driving systems, which take place on a public highway, is discussed. The experimental setup consist of a specific driver support system, which is closely related to cooperative adaptive cruise control (CACC) systems. Instead of auto

  6. Tele-Operated Laboratories for Online Production Engineering Education - Platform for E-Learning and Telemetric Experimentation (PeTEX

    Directory of Open Access Journals (Sweden)

    A. Erman Tekkaya

    2011-09-01

    Full Text Available The development of tele-operated experimentation and its provision to distance learners opens new dimensions for experience-based scientific and engineering education, particularly where experiments are the core elements of teaching and learning. The finalized EU-funded project PeTEX–Platform for e-Learning and Telemetric Experimentation has developed a prototype of an e-learning platform based on the learning and content management system Moodle for the design and implementation of educational and training applications in the field of production engineering. The principle goal of this project was to establish individual and group oriented learning for different target groups like students and professional workers within a platform-system capable to serve a multi-lingual learning community. Hence, an educational model was designed which integrates the tele-operated experimentation platform with teaching content and learning activities in order to support a successful learning walkthrough for different target groups.

  7. In situ mortality experiments with juvenile sea bass (Dicentrarchus labrax in relation to impulsive sound levels caused by pile driving of windmill foundations.

    Directory of Open Access Journals (Sweden)

    Elisabeth Debusschere

    Full Text Available Impact assessments of offshore wind farm installations and operations on the marine fauna are performed in many countries. Yet, only limited quantitative data on the physiological impact of impulsive sounds on (juvenile fishes during pile driving of offshore wind farm foundations are available. Our current knowledge on fish injury and mortality due to pile driving is mainly based on laboratory experiments, in which high-intensity pile driving sounds are generated inside acoustic chambers. To validate these lab results, an in situ field experiment was carried out on board of a pile driving vessel. Juvenile European sea bass (Dicentrarchus labrax of 68 and 115 days post hatching were exposed to pile-driving sounds as close as 45 m from the actual pile driving activity. Fish were exposed to strikes with a sound exposure level between 181 and 188 dB re 1 µPa².s. The number of strikes ranged from 1739 to 3067, resulting in a cumulative sound exposure level between 215 and 222 dB re 1 µPa².s. Control treatments consisted of fish not exposed to pile driving sounds. No differences in immediate mortality were found between exposed and control fish groups. Also no differences were noted in the delayed mortality up to 14 days after exposure between both groups. Our in situ experiments largely confirm the mortality results of the lab experiments found in other studies.

  8. A Comprehensive Experimental Comparison of Event Driven and Multi-Threaded Sensor Node Operating Systems

    Directory of Open Access Journals (Sweden)

    Cormac Duffy

    2008-03-01

    Full Text Available The capabilities of a sensor network are strongly influenced by the operating system used on the sensor nodes. In general, two different sensor network operating system types are currently considered: event driven and multi-threaded. It is commonly assumed that event driven operating systems are more suited to sensor networks as they use less memory and processing resources. However, if factors other than resource usage are considered important, a multi-threaded system might be preferred. This paper compares the resource needs of multi-threaded and event driven sensor network operating systems. The resources considered are memory usage and power consumption. Additionally, the event handling capabilities of event driven and multi-threaded operating systems are analyzed and compared. The results presented in this paper show that for a number of application areas a thread-based sensor network operating system is feasible and preferable.

  9. An Experimental Comparison of Event Driven and Multi-Threaded Sensor Node Operating Systems

    OpenAIRE

    Duffy, Cormac; Roedig, Utz; Herbert,John; Sreenan, Cormac J.

    2007-01-01

    Two different operating system types are currently considered for sensor networks: event driven and multi-threaded. This paper compares the two well-known operating systems TinyOS (event driven) and MANTIS (multi-threaded) regarding their memory usage, power consumption and processing capabilities. TinyOS and MANTIS are both ported to the DSYS25 sensor platform. Both operating systems are used to execute the same sensor network application and the aforementioned parameters of interest are mea...

  10. Experimental Study on Extremum Seeking Control for Efficient Operation of Air-side Economizer

    OpenAIRE

    Mu, Baojie; Li, Yaoyu; Seem, John E.

    2014-01-01

    The air-side economizers are a major class of energy-saving devices for ventilation and air conditioning systems by taking advantage of outdoor air during cool or cold weather. Typical rule based control cannot justify energy optimal operation, while model based optimization of air-side economizer operation depends on the accurate knowledge of system model and enthalpy sensing of the ambient and return-air. Such optimal operation is hard to achieve in practice due to inaccurate model and degr...

  11. Longitudinal vibration of pile in layered soil based on Rayleigh-Love rod theory and fictitious soil-pile model

    Institute of Scientific and Technical Information of China (English)

    Lü Shu-hui; WANG Kui-hua; WU Wen-bing; C. J. LEO

    2015-01-01

    The dynamic response of pile in layered soil is theoretically investigated when considering the transverse inertia effect. Firstly, the fictitious soil-pile model is employed to simulate the dynamic interaction between the pile and the soil layers beneath pile toe. The dynamic interactions of adjacent soil layers along the vertical direction are simplified as distributed Voigt models. Meanwhile, the pile and fictitious soil-pile are assumed to be viscoelastic Rayleigh-Love rods, and both the radial and vertical displacement continuity conditions at the soil-pile interface are taken into consideration. On this basis, the analytical solution for dynamic response at the pile head is derived in the frequency domain and the corresponding quasi-analytical solution in the time domain is then obtained by means of the convolution theorem. Following this, the accuracy and parameter value of the hypothetical boundaries for soil-layer interfaces are discussed. Comparisons with published solution and measured data are carried out to verify the rationality of the present solution. Parametric analyses are further conducted by using the present solution to investigate the relationships between the transverse inertia effects and soil-pile parameters.

  12. Wind energy sector in British Columbia

    International Nuclear Information System (INIS)

    British Columbia (BC) possesses significant wind energy resources, and many wind energy projects are currently in the planning phase or are already under construction. Wind power policies in the province have been designed to ensure the secure and orderly development of the wind power industry. Policies in the province include a 10-year exemption from participation rents for new projects as well as a policy that has established the maximum permissible noise levels for wind farms located near residential properties. BC's wind power development plan forms part of the province's aim to become electricity self-sufficient by 2016 while ensuring that clean or renewable energy generation accounts for at least 90 per cent of total generation. This guide provided an outline of the province's wind energy sector, and provided a listing of selected wind power operators. Details of new wind power projects were also presented. 11 fig.

  13. Study of soil interaction in a model building frame with plinth beam supported by pile group

    Science.gov (United States)

    Reddy, Ravikumar C.; Rao, Gunneswara T. D.

    2012-12-01

    This paper presents the results of static vertical load tests carried out on a model building frame with plinth beam supported by pile groups embedded in cohesionless soil (sand). The effect of soil interaction on displacements and rotation at the column base and also the shears and bending moments in the building frame were investigated. The experimental results have been compared with those obtained from the finite element analysis and conventional method of analysis. Soil nonlinearity in the axial direction is characterized by nonlinear vertical springs along the length of the pile (τ-z curves) and at the tip of the pile (Q-z curves) and in the lateral direction by the p-y curves. The results reveal that the conventional method gives the shear force in the column by about 20%, the bending moment at the column top about 10%, and at the column base about 20% to 30%, more than those from the experimental results. The response of the frame from the experimental results is in good agreement with that obtained by the nonlinear finite element analysis.

  14. 黄土地基中人工挖孔扩底灌注桩负摩阻力试验研究%EXPERIMENTAL STUDY OF NEGATIVE SKIN FRICTION FOR MAN-MADE CAST-IN-SITU BELLED PILES IN LOESS SOIL FOUNDATION

    Institute of Scientific and Technical Information of China (English)

    曹卫平; 赵敏

    2012-01-01

    通过2根试桩的现场预浸水再加载试验,研究湿陷性黄土地基中人工挖孔扩底灌注桩在预浸水过程及其之后的加载过程中桩身摩阻力、桩端反力及桩身中性点深度的发展变化规律,并与我国现行规范进行比较.结果表明:(1)桩周土浸水过程中,桩身负摩阻力、正摩阻力及桩端反力均逐渐增大,桩身中性点位置逐渐下移.浸水结束时,中性点深度比为0.54~0.61,远小于桩基规范的推荐值;(2)在桩顶施加竖向荷载过程中,桩身负摩阻力逐渐减小,而正摩阻力及桩端反力继续增大,桩身中性点位置逐渐上移.桩顶竖向荷载P=11000kN时,中性点深度比为0.15~0.61,也远小于桩基规范的推荐值;(3)在桩顶设计荷载作用下,实测的桩身负摩阻力大小、分布范围及分布形式与桩基规范及黄土规范的规定有较大的差异;(4)黄土地基中桩身负摩阻力及中性点深度随着桩周土浸水、桩顶荷载处于一个动态变化过程中,负摩阻力的大小也受到桩径的影响.%Field tests were conducted to investigate the behavior of negative skin friction, positive skin friction, pile end reaction and neutral plane depth for man-made cast-in-situ belled piles in loess under pre-immersing and loading condition. The test results were also compared with the regulations of the technical code for building pile foundation of China. The results show that: (1) With the pre-immersing, negative skin friction, positive skin friction and pile end reaction are induced and increase with further immersing and the neutral plane gradually descend. The neutral plane depth ratio reaches 0.54 - 0.61 at the end of pre-immersing process, which is far smaller than that introduced in the technical code for building pile foundation of China. (2) When vertical load is applied on the pile head, negative skin friction decrease accompanied by the increasing of positive skin friction and pile end reaction as well as

  15. Threat from Rubble-Pile Asteroids

    Science.gov (United States)

    Schultz, P. H.

    2015-12-01

    While chondrites are the most common meteoroids to enter our atmosphere, they represent a small fraction of recovered falls. Most stony meteorites disrupt during entry, consumed by ablation or lost by weathering; in contrast, small iron meteorites (entry at altitude; (c) no accessory meteorite falls; (d) "explosion" (not low-speed compression) crater; (e) infrasound/seismic data indicating a high-speed entry/collision; and (f) petrologic evidence for shock deformation/melting in breccias indicative of speeds >4 km/s. Although a monolithic chondrite (~ 10 m across) might allow surviving entry, most objects of this size contain multiple flaws, ensuring atmospheric disruption. Hence, an alternative "needle model" was proposed wherein a small rubble-pile object gradually re-shaped itself during entry [Schultz, 2008], a process that minimizes drag, thermal signatures of entry, and catastrophic disruption. First proposed to account for smaller than expected craters on Venus [Schultz, 1992], such a process resembles subsequent Shoemaker-Levy entry models [Boslough and Crawford, 1997] that predicted much deeper entry than standard models. Laboratory experiments at the NASA Ames Vertical Gun Range simulated this process by breaking-up hypervelocity projectiles into a cloud of debris and tracking its path at near-full atmospheric pressure. The resulting cloud of fragments exhibited less deceleration than a solid sphere at the same speed. Moreover, shadowgraphs revealed constituent fragments "surfing" the pressure jump within the mach cone/column. Previous models proposed that crater-forming impacts must be >50-100 m in diameter in order to survive entry [Bland and Artemieva, 2004]. The "needle model" for the Carancas meteorite entry, however, raises questions about this lower limit for threats by rubble-pile asteroids, e.g., Itokawa. Consequently, we modeled the fate of a rubble-pile entering earth's atmosphere using GEODYN, an Eulerian code with adaptive mesh refinement

  16. The stiffness change and the increase in the ultimate capacity for a stiff pile resulting from a cyclic loading

    DEFF Research Database (Denmark)

    Lada, Aleksandra; Ibsen, Lars Bo; Nicolai, Giulio

    In the paper the experimental results of small-scale tests on a stiff monopile are presented to outline the change in stiffness during the cyclic loading and the change in the ultimate pile capacity. The results confirm the increase of stiffness and the increase in bearing capacity resulting from...

  17. Numerical Simulation for the Soil-Pile-Structure Interaction under Seismic Loading

    OpenAIRE

    Lifeng Luan; Yunbin Liu; Ying Li

    2015-01-01

    Piles are widely used as reinforcement structures in geotechnical engineering designs. If the settlement of the soil is greater than the pile, the pile is pulled down by the soil, and negative friction force is produced. Previous studies have mainly focused on the interaction of pile-soil under static condition. However, many pile projects are located in earthquake-prone areas, which indicate the importance of determining the response of the pile-soil structure under seismic load. In this pap...

  18. Investigation of Pile- Soil Interaction Subjected to Lateral Loads in Layered Soils

    OpenAIRE

    A. Avaei; Ghotbi, Abdoul R.; M. Aryafar

    2008-01-01

    To stabilize infrastructures such as tall buildings, bridges, etc., piles are used to resist lateral loads created from earth pressure, wind, waves and earthquake extensively. Pile design requires understanding of how the load is transferred from a pile to surrounding soil and vice versa. Pile properties, soil stress-strain behavior and pile-soil interaction play important roles in pile-response subjected to lateral loads. A study was carried out to investigate the effects of above-mentioned ...

  19. Out-of-pile Verifying Test for the Hydraulic Stability of the CARR Standard Fuel Assembly

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The CARR standard fuel element is a flat-plate-type assembly. A fuel plate consists of 0.6 mmthickness layer of uranium- silicon - aluminum fuel (U3Si2-Al) and 0.38 mm thickness of aluminumcladding. The fuel plates are attached to aluminum alloy side plates by a "roll swaging" technique. Thistype of fuel assembly is first used in China. The testing simulates the in-pile thermal-hydraulic operating conditions except for neutron

  20. Application of pressuremeter measurements for the prediction of bearing capacity of verticaly loaded piles

    OpenAIRE

    Robas, Alenka

    2007-01-01

    Pressuremeter is an in situ test widely in operation in France, and in the last decade it has won recognition all over the world, as well as in Slovenia. Basically it is used to determinate the soil characteristics needed for the design of foundations. This thesis deals with the calculation of the bearing capacity of the vertically loaded piles using different methods based on pressuremeter measurements. The thesis deals only with buildings on deep foundations and because the u...

  1. Carbon deposition in CH4/CO2 operated SOFC: Simulation and experimentation studies

    Science.gov (United States)

    Girona, K.; Laurencin, J.; Fouletier, J.; Lefebvre-Joud, F.

    2012-07-01

    Due to their high operating temperatures, SOFCs can be directly fed with biogas, mainly composed of CH4 and CO2. In this work, experiments was performed with a classical Ni-YSZ cermet//YSZ//LSM cell fed either with a synthetic simulated biogas (CH4/CO2 ratio equal to 1 with 6% humidity), or with humidified H2. In both cases, the performances are found to be very similar, which confirms the ability of SOFCs to operate with internal reforming of biogas. Nevertheless, carbon formation in these operating conditions needs to be considered because of durability concerns. Thermodynamic calculations and modelling are carried out to evaluate the risk of carbon deposition depending on operating parameters. In the ternary diagram Csbnd Hsbnd O, the limits for carbon deposition are plotted, allowing the determination of “safe” operating conditions in terms of CH4 inlet flow rate and cell voltage. First experiments confirm these modelling results.

  2. Experimental studies of computerized procedures and team size in nuclear power plant operations

    International Nuclear Information System (INIS)

    The operation of a nuclear power plant is so complex that it requires teamwork. To support team performance, a system need to provide all team members integrated information displays as well as decision aids (e.g., computerized procedures). Two experiments were conducted to investigate the effects of computerized procedures and team size on operating performance. Forty-five participants were involved in the experiments. Each participant executed decision and action tasks to deal with alarm signals, while detecting occasional system errors in the interface. Results showed that effects of computerized procedures were significant on various performance indicators, such as operation time, operation errors, and learning effect, and that two operators would be a satisfactory size in the teamwork system providing computerized procedures

  3. INTERACTION OF A LONG SINGLE PILE THAT HAS A DOUBLE-LAYER BASE WITH ACCOUNT FOR COMPRESSIBILITY OF THE PILE SHAFT

    OpenAIRE

    Ter-Martirosyan Zaven Grigor'evich; Trinh Tuan Viet

    2012-01-01

    WITH ACCOUNT FOR COMPRESSIBILITY OF THE PILE SHAFT The authors provide their solution to the problem of interaction of a long compressible pile that has a double-layer linear deformable base. The paper demonstrates that taking account of compressible properties of the pile material leads to qualitatively new distribution of shearing stresses over the surface of a cylindrical pile. It is noteworthy that increase of the pile length and stiffness of the upper section of the base raise the sha...

  4. Seismic Analysis of Deep Water Pile Foundation Based on Three-Dimensional Potential-Based Fluid Elements

    Directory of Open Access Journals (Sweden)

    Kai Wei

    2013-01-01

    Full Text Available This paper investigates the use of three-dimensional (3D ϕ-u potential-based fluid elements for seismic analyses of deep water pile foundation. The mathematical derivations of the potential-based formulations are presented for reference. The potential-based modeling technique is studied and validated through experimental data and analytical solutions. Earthquake time history analyses for a 9-pile foundation in dry and different water environments are conducted, respectively. The seismic responses are discussed to investigate the complex effect of earthquake-induced fluid-structure interaction. Through the analyses, the potential-based fluid and interface elements are shown to perform adequately for the seismic analyses of pile foundation-water systems, and some interesting conclusions and recommendations are drawn.

  5. Examination of graphite pile radiation conditions of industrial reactors

    International Nuclear Information System (INIS)

    Radiation states of graphite piles of three industrial uranium-graphite reactors are investigated. The level, composition, distribution of the pile radioactive contamination, parameters of neutron and gamma radiations are determined. The forecast of variation of radionuclide activity in graphite in dependence on the cooling time is developed

  6. Cause Analysis of Wuhan Tianheng Building Pile Accident

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The geological condition and the original structure feature and foundation design of Wuhan Tianheng building are described. The accident appearance of pile foundation in the construction execution of work is illustrated. The generating source of this pile foundation accident is analyzed in great details.``

  7. Modeling the damming effect of pile foundations (Tomsk city)

    Science.gov (United States)

    Kuzevanov, K. I.; Pokrovsky, D. S.; Pokrovsky, V. D.; Kuzevanov, K. K.

    2016-03-01

    The authors have considered the impact of pile foundations on the structure of filtration flows in the conditions of urban development. Hydrodynamic simulation methods have shown that a groundwater level rise might occur due to the damming effect that can be created by pile fields in semipermeable rocks. This phenomenon can intensify anthropogenic waterlogging processes in urbanized territories.

  8. Physical Modelling of Cyclic Laterally Loaded Pile in Cohesionless Soil

    DEFF Research Database (Denmark)

    Hansen, Mette; Wolf, Torben K.; Rasmussen, Kristian L.;

    Offshore wind turbines are normally founded with large diameter monopiles and placed in rough environments subjected to variable lateral loads from wind and waves. A long-term lateral loading may create rotation (tilt) of the pile by change in the pile-soil system which is critical in the service...

  9. Assessment of timber piles in Clallam County, Washington

    Science.gov (United States)

    Pandey, Arun K.; Tyler, Ross; Arnette, Clyde G.; Anthony, Ronald W.

    1998-03-01

    Timber bridges are very common in state and rural highway systems. According to the National Bridge Inventory (NBI), there are 41,743 timber bridges in the United States and another 42,102 bridges with timber decks as a part of the superstructure. As these bridges age, there is a critical need for reliable inspection and assessment methods for evaluating timber members. Under an FHWA mandate, these bridges also need to be evaluated for scour susceptibility. Knowledge of the length of timber piles supporting the bridge is a vital component in calculating scour resistance of a bridge. However, records of timber pile lengths are often nonexistent or incomplete due to the construction practices for timber piles. This paper presents nondestructive evaluation (NDE) techniques used for assessing timber piles on 10 bridges in Clallam County, Washington. Stress wave velocity and resistance drilling techniques were used to determine the presence of and quantify the extent of decay in the piles. A longitudinal stress wave technique was used for determining the length of timber piles. Determination of piles with decay aided in establishing maintenance and repair needs on the bridge substructures. Pile length estimates enabled Clallam County Road Department to determine the scour-susceptibility of these bridges.

  10. Visualization of soil arching in flexible piled embankments

    Indian Academy of Sciences (India)

    Tuğba Eskışar

    2015-10-01

    Piled embankments rely on soil arching, but, when geogrid reinforcements are used, membrane action within the reinforcement contributes to load distribution. The arching of soil in unreinforced and reinforced piled embankments is evaluated in this study. A small-scale test apparatus is used to model the settlement up to 5 mm in an embankment with four pile elements. Visual inspection of the soil settlement and soil-reinforcement interaction is important to explain the mechanism of arching. In this study, X-ray Computed Tomography (CT) method was used as a non-destructive technique. The arching of soil between the piles was observed in the case of rigid piles and in the case of flexible piles with grid type of reinforcement. The load carrying capacity increased up to 33% in the case of geogrid reinforcement, and the differential settlement decreased around 35%, proving the efficiency of piled embankments with geogrid reinforcements. It is also shown that, using X-ray CT method and visualization techniques provides a better understanding of soil behavior in a reinforced embankment with the flexible pile foundation system.

  11. The homogenisation of bulk material in blending piles.

    NARCIS (Netherlands)

    Gerstel, A.W.

    1979-01-01

    In this thesis the homogenisation of bulk material in three types of piles is dealt with. The homogenisation implies that the fluctuations of a material proprety in the input flow of the pile are transformed into output fluctuations, whereby the latter ones are evened out. Analyses are presented con

  12. Perturbation analysis on post-buckling behavior of pile

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The nonlinear large deflection differential equation, based on the assumption that the subsoil coefficient is the 2nd root of the depth, was established by energy method. The perturbation parameter was introduced to transform the equation to a series of linear differential equations to be solved, and the deflection function according with the boundary condition was considered. Then,the nonlinear higher-order asymptotic solution of post-buckling behavior of a pile was obtained by parameter-substituting. The influencing factors such as bury-depth ratio and stiffness ratio of soil to pile, slenderness ratio on the post-buckling behavior of a pile were analyzed. The results show that the pile is more unstable when the bury-depth ratio and stiffness ratio of soil to pile increase,and although the buckling load increases with the stiffness of soil, the pile may ruin for its brittleness. Thus, in the region where buckling behavior of pile must be taken into account, the high grade concrete is supposed to be applied, and the dynamic buckling behavior of pile needs to be further studied.

  13. Implementation plan for the Waste Experimental Reduction Facility Restart Operational Readiness Review

    International Nuclear Information System (INIS)

    The primary technical objective for the WERF Restart Project is to assess, upgrade where necessary, and implement management, documentation, safety, and operation control systems that enable the resumption and continued operation of waste treatment and storage operations in a manner that is compliant with all environment, safety, and quality requirements of the US Department of Energy and Federal and State regulatory agencies. Specific processes that will be resumed at WERF include compaction of low-level compatible waste; size reduction of LLW, metallic and wood waste; incineration of combustible LLW and MLLW; and solidification of low-level and mixed low-level incinerator bottom ash, baghouse fly ash, and compatible sludges and debris. WERF will also provide for the operation of the WWSB which includes storage of MLLW in accordance with Resource Conservation and Recovery Act requirements

  14. Theoretical and experimental researches on the operating costs of a wastewater treatment plant

    Science.gov (United States)

    Panaitescu, M.; Panaitescu, F.-V.; Anton, I.-A.

    2015-11-01

    Purpose of the work: The total cost of a sewage plants is often determined by the present value method. All of the annual operating costs for each process are converted to the value of today's correspondence and added to the costs of investment for each process, which leads to getting the current net value. The operating costs of the sewage plants are subdivided, in general, in the premises of the investment and operating costs. The latter can be stable (normal operation and maintenance, the establishment of power) or variables (chemical and power sludge treatment and disposal, of effluent charges). For the purpose of evaluating the preliminary costs so that an installation can choose between different alternatives in an incipient phase of a project, can be used cost functions. In this paper will be calculated the operational cost to make several scenarios in order to optimize its. Total operational cost (fixed and variable) is dependent global parameters of wastewater treatment plant. Research and methodology: The wastewater treatment plant costs are subdivided in investment and operating costs. We can use different cost functions to estimate fixed and variable operating costs. In this study we have used the statistical formulas for cost functions. The method which was applied to study the impact of the influent characteristics on the costs is economic analysis. Optimization of plant design consist in firstly, to assess the ability of the smallest design to treat the maximum loading rates to a given effluent quality and, secondly, to compare the cost of the two alternatives for average and maximum loading rates. Results: In this paper we obtained the statistical values for the investment cost functions, operational fixed costs and operational variable costs for wastewater treatment plant and its graphical representations. All costs were compared to the net values. Finally we observe that it is more economical to build a larger plant, especially if maximum loading

  15. Experimental Identification and Study of Hydraulic Resonance Test Rig with Francis Turbine operating at Partial Load

    OpenAIRE

    Favrel, Arthur; Landry, Christian; Müller, Andres; Avellan, François

    2013-01-01

    Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating vortex rope developing at the outlet of the runner induces pressure fluctuations which can excite the hydraulic system resonance, leading to undesirable large torque and power fluctuations. At resonant operating points, the prediction of am...

  16. Experimental Study on Series Operation of Sliding Vane Pump and Centrifugal Pump

    OpenAIRE

    Tao Li; Weiming Zhang; Ming Jiang; Zhengyang Li

    2013-01-01

    A platform for sliding vane pump and centrifugal pump tests is installed to study the series operation of them under different characteristics of pipeline. Firstly, the sliding vane pump and the centrifugal pump work independently, and the performance is recorded. Then, the two types of pumps are combined together, with the sliding vane pump acting as the feeding pump. Comparison is made between the performance of the independently working pump and the performance of series operation pump. Re...

  17. Sir Charles Ballance: pioneer British neurological surgeon.

    Science.gov (United States)

    Stone, J L

    1999-03-01

    nerve regeneration and nerve grafting, and after many years of devoted research, he devised successful operations for facial nerve paralysis. For this and early vascular work, he is often credited as the first English surgeon to reintroduce classical Hunterian methods of experiment into surgery. He was honored as the founder and President of The Society of British Neurological Surgeons in 1926. Perhaps best known as a general and aural surgeon, Ballance was second only to Horsley in reputation as a pioneer British neurological surgeon. Described as a painstakingly slow but delicate and meticulous operator, Ballance made a contribution to neurosurgery and temporal bone surgery that was immense.

  18. 40 CFR 264.251 - Design and operating requirements.

    Science.gov (United States)

    2010-07-01

    ....251 Section 264.251 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Waste Piles § 264.251 Design and operating requirements. (a) A waste pile (except for an...

  19. Optimum design methodologies for pile foundations in London

    Directory of Open Access Journals (Sweden)

    Christos Letsios

    2014-12-01

    Full Text Available Given the importance of pile foundations in geotechnical engineering for supporting high-significance structures such as bridges, high-rise buildings, power plant stations, offshore platforms and museums, it becomes a necessity to find the best pile foundation design in terms of performance and economy. The number of piles required might exceed several hundreds or even thousands while the pile foundation cost might exceed 20% of the construction cost of the superstructure. In this work the problem of finding optimized designs of pile foundations is examined and is performed in accordance to two design code recommendations, namely Eurocode 7 and DIN 4014. The proposed structural optimization procedure is implemented in two real-world cases both located in London, UK in order to assess the efficiency of the proposed design formulation.

  20. The Analysis of Soil Resistance During Screw Displacement Pile Installation

    Science.gov (United States)

    Krasinski, Adam

    2015-02-01

    The application of screw displacement piles (SDP) is still increasing due to their high efficiency and many advantages. However, one technological problem is a serious disadvantage of those piles. It relates to the generation of very high soil resistance during screw auger penetration, especially when piles are installed in non-cohesive soils. In many situations this problem causes difficulties in creating piles of designed length and diameter. It is necessary to find a proper method for prediction of soil resistance during screw pile installation. The analysis of screw resistances based on model and field tests is presented in the paper. The investigations were carried out as part of research project, financed by the Polish Ministry of Science and Higher Education. As a result of tests and analyses the empirical method for prediction of rotation resistance (torque) during screw auger penetration in non-cohesive subsoil based on CPT is proposed.

  1. Dynamic Soil-Pile Interaction for large diameter monopile foundations

    DEFF Research Database (Denmark)

    Zania, Varvara

    2013-01-01

    of the study is to analyse the dynamic interaction of the soil and a single pile embedded in it by accounting for the geometric and stiffness properties of the pile. In doing so, a semi – analytical approach is adopted based on the fundamental solution of horizontal pile vibration by Novak and Nogami...... eigenfrequencies of the soil layer do not affect the soil – pile interaction. The decrease of the eigefrequency of the OWT depends on the aforementioned variation of the dynamic stiffness and the slenderness ratio of the monopile....... left between two restrictive frequency areas. Moreover the design of monopile foundations when subjected to combined lateral and moment loading (the latter arising from the eccentricity of the applied wind pressure) usually dictates a large diameter steel pile with small slenderness ratio. Hence, aim...

  2. Static Tension Tests on Axially Loaded Pile Segments in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    showed best agreement with the traditional design method given in the American Petroleum Institute (API) design code. When t-z curves obtained from the test results were compared to t-z curve formulations found in the literature, the Zhang formulation gave good predictions of the initial and post......This paper provides laboratory test results of static axially loaded piles in sand. With a newly developed test setup, the pile-soil interface friction was investigated by using an open-ended steel pile segment with a diameter of 0.5 m. Use of a pile length of 1 m enabled the pile-soil interface...... friction to be analyzed at a given soil horizon while increasing the vertical effective stress in the sand. Test results obtained by this approach can be analyzed as single t-z curves and compared to predictions of unit shaft friction from current design methods for offshore foundations. The test results...

  3. The Analysis of Soil Resistance During Screw Displacement Pile Installation

    Directory of Open Access Journals (Sweden)

    Krasinski Adam

    2015-02-01

    Full Text Available The application of screw displacement piles (SDP is still increasing due to their high efficiency and many advantages. However, one technological problem is a serious disadvantage of those piles. It relates to the generation of very high soil resistance during screw auger penetration, especially when piles are installed in non-cohesive soils. In many situations this problem causes difficulties in creating piles of designed length and diameter. It is necessary to find a proper method for prediction of soil resistance during screw pile installation. The analysis of screw resistances based on model and field tests is presented in the paper. The investigations were carried out as part of research project, financed by the Polish Ministry of Science and Higher Education. As a result of tests and analyses the empirical method for prediction of rotation resistance (torque during screw auger penetration in non-cohesive subsoil based on CPT is proposed.

  4. Distributed fibre optic strain measurements on a driven pile

    Science.gov (United States)

    Woschitz, Helmut; Monsberger, Christoph; Hayden, Martin

    2016-05-01

    In civil engineering pile systems are used in unstable areas as a foundation of buildings or other structures. Among other parameters, the load capacity of the piles depends on their length. A better understanding of the mechanism of load-transfer to the soil would allow selective optimisation of the system. Thereby, the strain variations along the loaded pile are of major interest. In this paper, we report about a field trial using an optical backscatter reflectometer for distributed fibre-optic strain measurements along a driven pile. The most significant results gathered in a field trial with artificial pile loadings are presented. Calibration results show the performance of the fibre-optic system with variations in the strain-optic coefficient.

  5. Centrifuge Modeling of Piles Subjected to Lateral Loads

    Science.gov (United States)

    Brant, Logan; Ling, Hoe I.

    There are many applications where piles are employed to absorb and deflect lateral impact loads. Structural elements of this type are used to protect infrastructure and are commonly found at marine sites. A series of model tests have been conducted using Columbia University's centrifuge facility to better understand the performance of piles subjected to these loading conditions. A device was designed to install and laterally load single model piles during centrifuge flight. This device uniquely contains two lateral loading systems, one which allows static testing and another appropriate for dynamic tests. This research examines the behavior of tubular steel piles embedded within dry or saturated soil and subjected to varied rates of lateral loading. This investigation provides insight on the contribution of lateral loading rates to the behavior of piles.

  6. Pre-Stressed Rope Reinforced Anti-Sliding Pile

    Institute of Scientific and Technical Information of China (English)

    XU Jun; WANG Chenghua

    2006-01-01

    Pre-stressed rope reinforced anti-sliding pile is a composite anti-sliding structure. It is made up of pre-stressed rope and general anti-sliding pile. It can bring traditional anti-sliding pile's retaining performance into full play, and to treat with landslide fast and economically. The difference between them is that the pre-stressed rope will transfix the whole anti-sliding pile through a prearranged pipe in this structure. The working mechanics, the design method and economic benefit are studied. The results show that the pre-stressed rope reinforced anti-sliding pile can treat with the small and middle landslides or high slopes well and possess the notable advantage of technology and economic.

  7. Application of PCC pile in soil improvement of highway

    Institute of Scientific and Technical Information of China (English)

    刘芝平; 刘汉龙; 谭慧明

    2008-01-01

    The construction process and load-bearing behaviors of Cast-in-place concrete thin-wall pipe piles are analyzed based on its application on Yantong Expressway Project. The low strain test, static load test and field excavation were also carried out, and the bearing capacity of the new pile can meet the requirements of design. With the increase of pile diameter, the bearing capacity is increased. The settlement of composite foundation is decreased, when the replacement ratio of pile is increased. The test results also show that the load carried by inner soils is neglectable. According to the tests and application, it can be concluded that the new type of pile is convenient to construction with high bearing capacity and reliable quality, which has great potential in practical engineering.

  8. Rebel alliances: the means and ends of contemporary British anarchisms

    OpenAIRE

    Franks, Benjamin

    2000-01-01

    This thesis examines, classifies and evaluates the tactics and organisational methods of British and Irish anarchist groups, which operated in the period 1984-1999 (although reference is made to groupings and events outside of this period). The thesis explains how class struggle anarchism, which was a minority trend even within the libertarian milieu, has developed into a significant and lively (anti-)political movement. This thesis examines recent groups through their own publications and th...

  9. Experimental Study on Soil Arching Effect in Pile-supported Reinforced Embankment Under Dynamic Train Loads with Large Number of Vibration Cycles%大振次列车动荷载作用下桩网加筋路堤土拱效应模型试验研究

    Institute of Scientific and Technical Information of China (English)

    陈仁朋; 汪焱卫; 陈金苗; 边学成

    2015-01-01

    Through a full scale model test on pile-supported reinforced embankment,by exerting 1.2 m times dynamic axle load to the embankment under the condition of a train moving at a speed of 324 km/h,this paper studied the variation of dynamic soil stress with vibration times at the level of pile caps and in the 3.2 m em-bankment range.The development of the soil arch under long-term dynamic load was analyzed as well.The ex-periment results showed that when the pile-soil differential settlement was relatively large,the pile caps sus-tained nearly 90 percent of static load and dynamic load.As the soil arch strengthened the transmission of the dynamic stress in the embankment to the pile cap,the Boussinesq equation was not applicable to the calculation of distribution of dynamic stress in the embankment.Under long-term dynamic loads,the dynamic pile-soil stress ratio decreased,but the decrease was slight,indicating minor degeneration of the soil arch.%通过桩网加筋路堤足尺模型试验,研究速度324 km/h 时列车120万次轮轴动荷载作用下,桩帽高度位置和3.2 m 路基范围内动土压力随振次的变化规律,分析长期动荷载作用下土拱演化规律。试验结果表明:桩土差异沉降较大时,桩帽承担约90%的动荷载和静荷载,土拱加强了路基中动应力往桩帽的传递,路基中动应力分布按 Boussinesq 公式计算不合理;长期动荷载作用下,桩土动应力比减小,但幅度变化不大,说明土拱弱化不明显。

  10. British overseas retailing, 1900-60:international firm characteristics, market selections and entry modes

    OpenAIRE

    Alexander, Nicholas

    2011-01-01

    The early activities of British international retailers remain relatively unexplored and little understood. This paper considers the role of British companies operating through retail outlets in overseas markets. It identifies the characteristics of those companies, their retail activities, the markets selected and the entry methods used. This paper seeks to begin the process of addressing a considerable gap in the history literature. The findings presented in the paper are placed within a hi...

  11. Experimental Investigation on Low Magnetic Field Operation of an Overmoded Slow-Wave High-Power Microwave Generator

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jun; ZHONG Hui-Huang; SHU Ting; LUO Ling; WANG Yong

    2004-01-01

    @@ The experimental results of an overmoded slow-wave high-power microwave generator operated at low magnetic field are presented. The feasibility of low magnetic field operation is investigated both theoretically and experimentally based on the characteristics of the overmoded slow-wave device. The experiments were carried out at the Spark-2 accelerator. Under the condition of guiding magnetic field strength of 0.55 T, diode voltage of 474 k V,and beam current of 5.2kA, a microwave was generated with power of 510MW, mode of TM01, and frequency of 9.54 GHz. The relative half-width of the frequency spectrum is less than 1%, and the beam-to-microwave efficiency is about 21% in our experiments.

  12. The Development and Improvement on Cathodic Protection Test Pile%阴极保护测试桩的发展与改进

    Institute of Scientific and Technical Information of China (English)

    丛军

    2012-01-01

    阴极保护测试桩的样式并无统一规定,混凝土测试桩适用于热油管道,用于天然气及成品油管道,巡线时难以寻找;钢管测试桩存在不法分子盗损的问题;特殊设计的防盗测试桩较好地满足了各种管道阴极保护运行的要求。%There is no unified regulation on the style of cathodic protection test pile, for instance: the concretes test pile is suitable for hot oil pipeline, but is not suitable for line-tracking, the steel test pile is likely to be stolen; while the anti-theft test pile can meet the demands of cathodic protection operation for all kinds of pipelines.

  13. Experimental Verification of Dynamic Operation of Continuous and Multivessel Batch Distillation

    Energy Technology Data Exchange (ETDEWEB)

    Wittgens, Bernd

    1999-07-01

    This thesis presents a rigorous model based on first principles for dynamic simulation of the composition dynamics of a staged high-purity continuous distillation columns and experiments performed to verify it. The thesis also demonstrates the importance of tray hydraulics to obtain good agreement between simulation and experiment and derives analytic expressions for dynamic time constants for use in simplified and vapour dynamics. A newly developed multivessel batch distillation column consisting of a reboiler, intermediate vessels and a condenser vessel provides a generalization of previously proposed batch distillation schemes. The total reflux operation of this column was presented previously and the present thesis proposes a simple feedback control strategy for its operation based on temperature measurements. The feasibility of this strategy is demonstrated by simulations and verified by laboratory experiments. It is concluded that the multivessel column can be easily operated with simple temperature controllers, where the holdups are only controlled indirectly. For a given set of temperature setpoints, the final product compositions are independent of the initial feed composition. When the multivessel batch distillation column is compared to a conventional batch column, both operated under feedback control, it is found that the energy required to separate a multicomponent mixture into highly pure products is much less for the multivessel system. This system is also the simplest one to operate.

  14. Experimental Study on Series Operation of Sliding Vane Pump and Centrifugal Pump

    Directory of Open Access Journals (Sweden)

    Tao Li

    2013-01-01

    Full Text Available A platform for sliding vane pump and centrifugal pump tests is installed to study the series operation of them under different characteristics of pipeline. Firstly, the sliding vane pump and the centrifugal pump work independently, and the performance is recorded. Then, the two types of pumps are combined together, with the sliding vane pump acting as the feeding pump. Comparison is made between the performance of the independently working pump and the performance of series operation pump. Results show that the system flow rate is determined by the sliding vane pump. In order to ensure the stability of the series operation pumping system, the energy consumption required by the pipeline under the system flow should be greater than the pressure energy centrifugal pump can generate. Otherwise, the centrifugal pump can not operate stably, with reflux, swirl, gas-liquid two-phase flow in the runner and strong vibration and noise. The sliding vane pump can be in serial operation with the centrifugal pump under limited conditions.

  15. Influence of space of double row piles on soil arching effect

    Directory of Open Access Journals (Sweden)

    Zhao bo

    2015-02-01

    Full Text Available FLAC3d software, based on continuous theory, is used to analysis influence of space of double row piles on soil arching effect. The result shows that different from single row pile, double row piles will produce soil arching effect at front pile and rear pile severally, this phenomenon is called multiple soil arching effect; the residual load of front of front row pile will increase,the soil arch zone and the soil arching effect will decrease with the continuous increase of double row pile spacing.At the same time the soil arching effect of rear pile decreases, while the soil arching effect of front pile increases and finally the soil arching effect between front pile and rear pile will be equal.

  16. Experimental on-demand recovery of entanglement by local operations within non-Markovian dynamics.

    Science.gov (United States)

    Orieux, Adeline; D'Arrigo, Antonio; Ferranti, Giacomo; Lo Franco, Rosario; Benenti, Giuliano; Paladino, Elisabetta; Falci, Giuseppe; Sciarrino, Fabio; Mataloni, Paolo

    2015-02-25

    In many applications entanglement must be distributed through noisy communication channels that unavoidably degrade it. Entanglement cannot be generated by local operations and classical communication (LOCC), implying that once it has been distributed it is not possible to recreate it by LOCC. Recovery of entanglement by purely local control is however not forbidden in the presence of non-Markovian dynamics, and here we demonstrate in two all-optical experiments that such entanglement restoration can even be achieved on-demand. First, we implement an open-loop control scheme based on a purely local operation, without acquiring any information on the environment; then, we use a closed-loop scheme in which the environment is measured, the outcome controling the local operations on the system. The restored entanglement is a manifestation of "hidden" quantum correlations resumed by the local control. Relying on local control, both schemes improve the efficiency of entanglement sharing in distributed quantum networks.

  17. Experimental Study of Polymer Electrolyte Membrane Fuel Cell Performance Under Low Operating Temperatures

    International Nuclear Information System (INIS)

    In this study, the performance characteristics of a polymer electrolyte membrane fuel cell (PEMFC) were investigated at low operating temperatures under steady-state and dynamic conditions. The performance of the PEMFC was analyzed according to the external humidifying rate and air stoichiometry. The ohmic resistance was also investigated using EIS tests. At the operating temperature of 35 ℃, voltage fluctuation occurred to a greater degree compared to that at 45 ℃. Therefore, it was found that the air stoichiometry should be higher than 2.5 for the stable operation of the fuel cell. In addition, the relative humidity of the reactant gases should be higher than 60 to reduce the ohmic resistance

  18. ITER: design, construction and operation of te first experimental nuclear fusion reactor

    International Nuclear Information System (INIS)

    The ITER project's mission is to demonstrate the scientific and technological feasibility of fusion power for peaceful purposes and its now under construction at Saint Paul-Lez-Durance (France). The ITER reactor is based on the 'tokamak' concept of plasma magnetic confinement, in which the fusion (deuterium-tritium) fuel is contained in a doughnut-shaped vessel. The plasma is kept away from the vessel walls by strong magnetic fields produced by superconducting coils surrounding the vessel and by an electrical current driven in the plasma. The ITER reactor is designed to generate 500 MW of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10 (Q ≥ 10). ITER will also aim at demonstrating long fusion power production pulses, of at least 1000 seconds, with a fusion power multiplication factor of 5 and, ultimately, of 1 hour duration (only limited by hardware design limits) when full non-inductive operation is demonstrated. The presentation will cover the following aspects of the ITER reactor design, construction and foreseen operation: a) The basis for power production by magnetic confinement tokamak fusion reactors. b) The main features of the ITER tokamak reactor design. c) The key design principles of the ITER tokamak and of the key ancillary systems required for the operational scenarios considered to achieve the project's mission. d) The design and progress in qualification and manufacturing of the key ITER tokamak infrastructure, tokamak components and ancillary systems. e) The operational plan from the initial commissioning phase, through operation with non-nuclear hydrogen-helium plasmas to nuclear operation with deuterium-tritium plasmas and the demonstration of high Q fusion power. (author)

  19. Self operating absorption cooling system using solar energy: Small power experimental plant

    Science.gov (United States)

    Velluet, P.; Dehausse, R.

    This study deals with a solar system for refrigeration specially designed for remote areas conditions. So, it must be very simple and reliable, and in addition it must be also mechanically self-operating. The thermodynamic cycle used is an ammonia-water absorption one. It consumes only thermal energy, which is easily and cheaply converted directly from solar radiation. In order to make a self-operating system, an engine is located between the boiler (at high pressure) and the absorber (at low pressure). It expands ammonia vapor and produces mechanical energy to run the solution pump.

  20. Studying radon exhalation rates variability from phosphogypsum piles in the SW of Spain

    Energy Technology Data Exchange (ETDEWEB)

    López-Coto, I., E-mail: israel.lopez@dfa.uhu.es [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain); Mas, J.L. [Dpto. Física Aplicada I. Escuela Politécnica Superior, University of Sevilla, C/Virgen de Africa 7, 41012 Sevilla (Spain); Vargas, A. [Universitat Politècnica de Catalunya, Instituto de Técnicas Energéticas, Campus Sud Edificio ETSEIB, Planta 0, Pabellón C, Av. Diagonal 647, 08028 Barcelona (Spain); Bolívar, J.P. [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain)

    2014-09-15

    Highlights: • Variability of radon exhalation rates from PG piles has been studied using numerical simulation supported by experimental data. • Most relevant parameters controlling the exhalation rate are radon potential and moisture saturation. • Piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. • A proposed cover here is expected to allow exhalation rates reductions up to 95%. - Abstract: Nearly 1.0 × 10{sup 8} tonnes of phosphogypsum were accumulated during last 50 years on a 1200 ha disposal site near Huelva town (SW of Spain). Previous measurements of exhalation rates offered very variable values, in such a way that a worst case scenario could not be established. Here, new experimental data coupled to numerical simulations show that increasing the moisture contents or the temperature reduces the exhalation rate whilst increasing the radon potential or porosity has the contrary effect. Once the relative effects are compared, it can be drawn that the most relevant parameters controlling the exhalation rate are radon potential (product of emanation factor by {sup 226}Ra concentration) and moisture saturation of PG. From wastes management point of view, it can be concluded that piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. Furthermore, a proposed cover here is expected to allow exhalation rates reductions up to 95%. We established that the worst case scenario corresponds to a situation of extremely dry winter. Under these conditions, the radon exhalation rate (0.508 Bq m{sup −2} s{sup −1}) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bq m{sup −2} s{sup −1})

  1. Transfer of bacteria between biomaterials surfaces in the operating room - An experimental study

    NARCIS (Netherlands)

    Knobben, Bas A. S.; van der Mei, Henny C.; van Horn, Jim R.; Busscher, Henk J.

    2007-01-01

    Bacterial adhesion to and transfer between surfaces is a complicated process. With regard to the success of biomaterials implants, studies on bacterial adhesion and transfer should not be confined to biomaterials surfaces in the human body, but also encompass surfaces in the operating room, where th

  2. Members' Preferences for Co-operative Structures: An Experimental Conjoint Study

    NARCIS (Netherlands)

    Kalogeras, N.; Lans, van der I.A.; Pennings, J.M.E.; Dijk, van G.

    2004-01-01

    Abstract As market conditions change rapidly in the 21st century, questions arise concerning how the organizational structures of co-operatives (co-ops) can meet the challenges that these new conditions pose. This paper introduces a framework to structure marketing co-ops (MCs) based on members¿ pre

  3. Initial Experimental Result of Accurately Controlled Routinely Operated Signal System (ACROSS)

    Institute of Scientific and Technical Information of China (English)

    Liao Chengwang; Zhuang Cantao; Liang Hongsen

    2003-01-01

    The principle of Accurately Controlled Routinely Operated Signal System (ACROSS) isintroduced in this paper. A sample machine is made and tested. The experiment shows that thesignal-stacking technique is effective in improving signal-to-noise ratio and the sompi cepstrummethod is applicable to deconvolute a set of travel times of wave elements from accuratetransfer function data in frequency domain.

  4. Report On Design And Preliminary Data Of Halden In-Pile Creep Rig

    Energy Technology Data Exchange (ETDEWEB)

    Terrani, Kurt A [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Karlsen, T. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    A set of in-pile creep tests is ongoing in the Halden reactor on ORNL’s candidate accident tolerant fuel cladding materials. These tests are meant to provide essential material property information that is needed for an informed analysis of these fuel concepts under normal operating conditions. These tests provide detailed information regarding swelling, thermal creep, and irradiation creep rates of these materials. The results to date have been compared with the limited set of information available in literature that is form irradiation tests in other reactors or out-of-pile tests. Most of the results are in good agreement with prior literature, except for irradiation creep rate of SiC. To elucidate the difference between the HFIR and Halden test results continued testing is necessary. The tests describe in this progress report are ongoing and will continue for at least another year.

  5. Experimental Hydrologic Ensemble Forecast System for Collaborative R&D and Research-to-Operations Transition in NWS

    Science.gov (United States)

    Seo, D.; Liu, Y.; Herr, H.

    2008-12-01

    Providing uncertainty information is one of the most pressing needs of operational hydrologic forecasting in the National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) today. To address this need, the NWS Office of Hydrologic Development (OHD) is developing the EXperimental Ensemble Forecast System (XEFS), an integrated short- to long-range hydrologic ensemble prediction system to be implemented at the NWS River Forecast Centers for experimental operation within the next two years. The baseline system includes the Ensemble Pre-Processor (EPP3), Ensemble Streamflow Prediction (ESP2) subsystem, Hydrologic Model Output Statistics (HMOS) streamflow ensemble processor, Ensemble Post-Processor (EnsPost) and the Ensemble Product Generator (EPG), and will use the service-oriented architecture of the Early Flood Warning System (FEWS) of Deltares. To support in-house and collaborative research and development of hydrologic ensemble prediction and data assimilation capabilities, NWS/OHD is developing a research and development version of XEFS, or R&D XEFS, of which the above baseline system is a subset. In this presentation, we describe the overall framework and major components of the R&D XEFS, progress to date, plans, challenges and opportunities for collaborative R&D and research-to-operations transition of the research outcome into NWS hydrologic operations and services.

  6. Toward next-generation optical networks: a network operator perspective based on experimental tests and economic analysis

    Science.gov (United States)

    Xiao, Xiaojun; Du, Chunsheng; Zhou, Rongsheng

    2004-04-01

    As a result of data traffic"s exponential growth, network is currently evolving from fixed circuit switched services to dynamic packet switched services, which has brought unprecedented changes to the existing transport infrastructure. It is generally agreed that automatic switched optical network (ASON) is one of the promising solutions for the next generation optical networks. In this paper, we present the results of our experimental tests and economic analysis on ASON. The intention of this paper is to present our perspective, in terms of evolution strategy toward ASON, on next generation optical networks. It is shown through experimental tests that the performance of current Pre-standard ASON enabled equipments satisfies the basic requirements of network operators and is ready for initial deployment. The results of the economic analysis show that network operators can be benefit from the deployment of ASON from three sides. Firstly, ASON can reduce the CAPEX for network expanding by integrating multiple ADM & DCS into one box. Secondly, ASON can reduce the OPEX for network operation by introducing automatic resource control scheme. Finally, ASON can increase margin revenue by providing new optical network services such as Bandwidth on Demand, optical VPN etc. Finally, the evolution strategy is proposed as our perspective toward next generation optical networks. We hope the evolution strategy introduced may be helpful for the network operators to gracefully migrate their fixed ring based legacy networks to next generation dynamic mesh based network.

  7. Theater level operations: modeling ground unit logistical requirements in the Joint Warfare Analysis Experimental Prototype

    OpenAIRE

    Wilk, Thomas J.

    1995-01-01

    This study proposes a methodology for modeling the logistics processes for ground units in the Joint Warfare Analysis Experimental Prototype (JWAEP) simulation. The model structure presented in this research allows for the representation of the consumption. movement, and distribution of supplies within the combat units modeled in JWAEP. Also presented is an architecture to model logistical units in JWAEP Methodologies are presented to model both the "push" and "pull" systems of supply. The su...

  8. Apparent stress-strain relationships in experimental equipment where magnetorheological fluids operate under compression mode

    OpenAIRE

    Mazlan, SA; Ekreem, NB; Olabi, Abdul

    2008-01-01

    Abstract: This paper presents an experimental investigation of two different magnetorheological ( MR) fluids, namely, water-based and hydrocarbon-based MR fluids in compression mode under various applied currents. Finite element method magnetics was used to predict the magnetic field distribution inside the MR fluids generated by a coil. A test rig was constructed where the MR fluid was sandwiched between two flat surfaces. During the compression, the upper surface was moved towards the lower...

  9. Comparison of Different Methods for Determination of Pyrite Oxidation Rate in Wate Rock Pile at Mine Doyon, Quebec, Canada

    Science.gov (United States)

    Sracek, O.; Nicholson, R.; Gélinas, P.; Lefebvre, R.

    2004-05-01

    Mine Doyon is a gold mine located close to Noranda, Québec, Canada. The South waste rock pile contains mostly highly friable sericite schists with pyrite content up to 7 wt percent. Oxidation of pyrite resulted in the production of acid mine drainage with pH values of about 2.0, and sulfate concentrations in pore water above 200 g/L. The waste rock material is characterized by high permeability allowing thermally driven convective supply of oxygen at temperatures reaching up to 67oC close to the slopes of the pile. Several methods for the determination of pyrite oxidation rate (POR) in waste rock have been compared and evaluated. Methods based on data collected in situ such as the interpretation of oxygen concentration profiles in waste rock pile and pyrite concentrations in solid phase were compared with the oxygen consumption method (OCM) in the laboratory. Analytical 1-D solution based on oxygen and temperature profiles in the pile was used for preliminary determination of POR. Analytical modeling results were used as an input for 2-D numerical model using TOUGH AMD. POR values based on pyrite mass balance (PMB) in solid phase were also calculated, assuming that average pyrite content in the deep, almost non-oxidized zone of the pile represents pre-oxidation conditions. Calculations were performed for prismatic columns with 1 m2 base. An approach based on dissolved sulfate mass balance was not used because of the lack of data from early stage of the pile and the non-conservative behavior of sulfate (precipitation of gypsum and jarosite in the pile). Finally, the oxygen consumption method (OCM) in the laboratory was based on oxygen concentration decline in headspace of closed chamber, where samples of waste rock sprinkled by water were located. Both fresh samples from mining operation and partially weathered samples collected in the pile were used. A range of POR values (mol(O2).kg-1.s-1) were obtained from the various methods. At Site 6 on the slope of the pile

  10. 桩锚支护技术在深基坑中的应用与控制研究%Study on application and control of the pile-anchor supporting technology in deep foundation

    Institute of Scientific and Technical Information of China (English)

    张永俊

    2016-01-01

    介绍了桩锚支护的技术原理,分析了桩锚支护技术中易出现的问题,从降水作业、钢筋混凝土支护桩、锚索施工等方面,论述了桩锚支护技术在深基坑中的应用,提出了桩锚支护技术的发展方向。%The paper introduces pile-anchor supporting technology principles,analyzes problems easily occurring in pile-anchor supporting tech-nology,discusses the application of pile-anchor supporting technology in deep foundation from aspects of precipitation well operation,steel rein-forced concrete supporting pile,and anchor cable construction,and finally puts forward the development tendency of pile-anchor supporting technology.

  11. Experimental characterization and modelling of a cavitating centrifugal pump operating in fast start-up conditions

    OpenAIRE

    Duplaa, Sébastien; COUTIER-DELGOSHA, Olivier; DAZIN, Antoine; BOIS, Gérard; CAIGNAERT, Guy

    2010-01-01

    International audience The start-up of rocket engine turbopumps is generally performed only in a few seconds. It implies that these pumps reach their nominal operating conditions after only a few rotations. During these first rotations of the blades, the flow evolution in the pump is governed by transient phenomena, based mainly on the flow rate and rotation speed evolution. These phenomena progressively become negligible when the steady behavior is reached. The pump transient behaviour in...

  12. Optimization of an experimental hybrid microgrid operation: reliability and economic issues

    OpenAIRE

    Milo, Aitor; Gaztañaga, Haizea; Etxeberria Otadui, Ion; Bilbao, Endika; Rodríguez Cortés, Pedro

    2009-01-01

    In this paper a hybrid microgrid system, composed of RES (Renewable Energy System) and CHP (Combined Heat and Power) systems together with a battery based storage system is presented. The microgrid is accompanied by a centralized energy management system (CEMS) in order to optimize the microgrid operation both in grid-connected and in stand-alone modes. In grid-connected mode the optimization of the economic exploitation of the microgrid is privileged by applying optim...

  13. Intraperitoneal cytostatics impair early post-operative collagen synthesis in experimental intestinal anastomosesP6.

    OpenAIRE

    Martens, M F; Hendriks, T; Wobbes, T; DE PONT J.J.

    1992-01-01

    Collagen synthesis in intestinal anastomoses has been measured in rats after in vivo administration of cytostatics. The cytostatics were administered during 5 consecutive days either intravenously or intraperitoneally. On day 3 of the course the rats received both an ileal and a colonic anastomosis. The animals were sacrificed 3 and 7 days after operation. The cytostatics regimen used was a combination of 5-fluorouracil, bleomycin and cisplatinum in a dose of 10, 2 and 0.35 mg kg-1 day-1, res...

  14. Experimental design, operation, and results of a 4 kW high temperature steam electrolysis experiment

    Science.gov (United States)

    Zhang, Xiaoyu; O'Brien, James E.; Tao, Greg; Zhou, Can; Housley, Gregory K.

    2015-11-01

    High temperature steam electrolysis (HTSE) is a promising technology for large-scale hydrogen production. However, research on HTSE performance above the kW level is limited. This paper presents the results of 4 kW HTSE long-term test completed in a multi-kW test facility recently developed at the Idaho National Laboratory (INL). The 4 kW HTSE unit consisted of two solid oxide electrolysis stacks electrically connected in parallel, each of which included 40 electrode-supported planar cells. A current density of 0.41 A cm-2 was used for the long-term operating at a constant current mode, resulting in a theoretical hydrogen production rate about 23 slpm. A demonstration of 830 h stable operation was achieved with a degradation rate of 3.1% per 1000 h. The paper also includes detailed descriptions of the piping layout, steam generation and delivery system, test fixture, heat recuperation system, hot zone, instrumentation, and operating conditions. This successful demonstration of multi-kW scale HTSE unit will help to advance the technology toward near-term commercialization.

  15. Preliminary Experimental Results of Integrated Gasification Fuel Cell Operation Using Hardware Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Traverso, Alberto; Tucker, David; Haynes, Comas L.

    2012-07-01

    A newly developed integrated gasification fuel cell (IGFC) hybrid system concept has been tested using the Hybrid Performance (Hyper) project hardware-based simulation facility at the U.S. Department of Energy, National Energy Technology Laboratory. The cathode-loop hardware facility, previously connected to the real-time fuel cell model, was integrated with a real-time model of a gasifier of solid (biomass and fossil) fuel. The fuel cells are operated at the compressor delivery pressure, and they are fueled by an updraft atmospheric gasifier, through the syngas conditioning train for tar removal and syngas compression. The system was brought to steady state; then several perturbations in open loop (variable speed) and closed loop (constant speed) were performed in order to characterize the IGFC behavior. Coupled experiments and computations have shown the feasibility of relatively fast control of the plant as well as a possible mitigation strategy to reduce the thermal stress on the fuel cells as a consequence of load variation and change in gasifier operating conditions. Results also provided an insight into the different features of variable versus constant speed operation of the gas turbine section.

  16. Experimental investigation on operating instability of a dual compensation chamber loop heat pipe

    Institute of Scientific and Technical Information of China (English)

    FENG JianTing; LIN GuiPing; BAI LiZhan

    2009-01-01

    The operating instability of a dual compensation chamber loop heat pipe(DCC-LHP)including temperature hysteresis,reverse flow and temperature oscillation is described and explained in this paper.Test results indicate that the steady state operating temperature under the variable conductance mode is not the same during the power cycle testa with the same heat load,and it is lower during the power reduction cycle than that during the power increase cycle.Orientation has an effect on the heat load range when temperature hysteresis occurs,and the effect of power variation amplitude can be ignored.Reverse flow tends to occur in some of the startups at low heat loads,even if vapor existed in the vapor grooves initially,which is caused by a higher pressure inside the wick due to evaporation in the evaporator core or vapor penetration into it.Temperature oscillation tends to occur in some of the startups at low head loads or some steady-state operations at high heat loads.Especially when the compensation chamber with the bayonet through is above the evaporator,the incidence rate of temperature oscillation is high.

  17. Experimental investigation on operating instability of a dual compensation chamber loop heat pipe

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The operating instability of a dual compensation chamber loop heat pipe (DCC-LHP) including temperature hysteresis, reverse flow and temperature oscillation is described and explained in this paper. Test results indicate that the steady state operating temperature under the variable conductance mode is not the same during the power cycle tests with the same heat load, and it is lower during the power reduction cycle than that during the power increase cycle. Orientation has an effect on the heat load range when temperature hysteresis occurs, and the effect of power variation amplitude can be ignored. Reverse flow tends to occur in some of the startups at low heat loads, even if vapor existed in the vapor grooves initially, which is caused by a higher pressure inside the wick due to evaporation in the evaporator core or vapor penetration into it. Temperature oscillation tends to occur in some of the startups at low head loads or some steady-state operations at high heat loads. Especially when the compensation chamber with the bayonet through is above the evaporator, the incidence rate of temperature oscillation is high.

  18. Remedial action for radioactive waste rock piles in China

    International Nuclear Information System (INIS)

    The Chinese government has conducted remedial action for radioactive waste rock piles since 1990. The radioactive waste rocks produced in the course of geological exploration of uranium deposits are widely distributed over several hundreds of locations in more than 20 provinces in China. The following remedial actions for radioactive waste rock piles have been undertaken in China: 1. Protecting dams for stabilizing the piles have been built. A total length of about 50,000 m of these dams has been completed. 2. Soil layers have been emplaced on the radioactive waste rock piles. The focus of the action is to eliminate the radiation harmful to public health. A total area of 750,000 square meters of soil has been placed on the piles in China. 3. Radioactive waste rock piles have been vegetated. Aesthetic shaping of the landscape in the exploratory district of the uranium deposits is our expectant goal. A total area of about 560,000 square meters of vegetation has been placed on the soil covering the piles. Through these remedial actions, the environmental situation has been extensively improved in the remedial districts. The individual annual effective dose equivalent is less than 1 Sv/a. The radon emission rate is less than 20 pCi/m2.s. The gamma ray external exposure rate has been greatly reduced. Copyright (2001) Material Research Society

  19. Analysis of Wave Fields induced by Offshore Pile Driving

    Science.gov (United States)

    Ruhnau, M.; Heitmann, K.; Lippert, T.; Lippert, S.; von Estorff, O.

    2015-12-01

    Impact pile driving is the common technique to install foundations for offshore wind turbines. With each hammer strike the steel pile - often exceeding 6 m in diameter and 80 m in length - radiates energy into the surrounding water and soil, until reaching its targeted penetration depth. Several European authorities introduced limitations regarding hydroacoustic emissions during the construction process to protect marine wildlife. Satisfying these regulations made the development and application of sound mitigation systems (e.g. bubble curtains or insulation screens) inevitable, which are commonly installed within the water column surrounding the pile or even the complete construction site. Last years' advances have led to a point, where the seismic energy tunneling the sound mitigation systems through the soil and radiating back towards the water column gains importance, as it confines the maximum achievable sound mitigation. From an engineering point of view, the challenge of deciding on an effective noise mitigation layout arises, which especially requires a good understanding of the soil-dependent wave field. From a geophysical point of view, the pile acts like a very unique line source, generating a characteristic wave field dominated by inclined wave fronts, diving as well as head waves. Monitoring the seismic arrivals while the pile penetration steadily increases enables to perform quasi-vertical seismic profiling. This work is based on datasets that have been collected within the frame of three comprehensive offshore measurement campaigns during pile driving and demonstrates the potential of seismic arrivals induced by pile driving for further soil characterization.

  20. Three-dimensional analysis of slopes reinforced with piles

    Institute of Scientific and Technical Information of China (English)

    高玉峰; 叶茂; 张飞

    2015-01-01

    Based on the upper bound of limit analysis, the plane-strain analysis of the slopes reinforced with a row of piles to the 3D case was extended. A 3D rotational failure mechanism was adopted to yield the upper bound of the factor of safety. Parametric studies were carried out to explore the end effects of the slope failures and the effects of the pile location and diameter on the safety of the reinforced slopes. The results demonstrate that the end effects nearly have no effects on the most suitable location of the installed piles but have significant influence on the safety of the slopes. For a slope constrained to a narrow width, the slope becomes more stable owing to the contribution of the end effects. When the slope is reinforced with a row of piles in small space between piles, the effects of group piles are significant for evaluating the safety of slopes. The presented method is more appropriate for assessing the stability of slopes reinforced with piles and can be also utilized in the design of plies stabilizing the unstable slopes.

  1. The Contemporaneity of the British Survey.

    Science.gov (United States)

    Dodson, Charles Brooks

    The seeming remoteness of material studied in a British literature survey course can be frustrating for the teacher. Students may find little relevance in the story of Beowulf or the descriptions of Gulliver's voyages. However, instructors can highlight the contemporaneity of British literary texts by drawing parallels to modern times. For…

  2. British African Caribbean Women and Depression

    Science.gov (United States)

    Adkison-Bradley, Carla; Maynard, Donna; Johnson, Phillip; Carter, Stephaney

    2009-01-01

    Depression is a common condition among women in the United Kingdom. However, little is known about the context of depression among British African Caribbean women. This article offers a preliminary discussion regarding issues and information pertaining to depression among British African Caribbean women. Characteristics and symptoms of depression…

  3. The Current Canon in British Romantics Studies.

    Science.gov (United States)

    Linkin, Harriet Kramer

    1991-01-01

    Describes and reports on a survey of 164 U.S. universities to ascertain what is taught as the current canon of British Romantic literature. Asserts that the canon may now include Mary Shelley with the former standard six major male Romantic poets, indicating a significant emergence of a feminist perspective on British Romanticism in the classroom.…

  4. British and American literatures and English education

    Institute of Scientific and Technical Information of China (English)

    田露

    2011-01-01

    British and American literature teachings and university English the teaching isn't self-contradict,can be complement each other.Strengthen British and American literature teachings,contribute to an improvement our country English education,develop high c

  5. The Falklands War and the British Stage

    Directory of Open Access Journals (Sweden)

    Radu Adrian

    2014-03-01

    Full Text Available The paper examines the way the Falklands War of 1982 was reflected in the creation of British playwrights. Officially, the war was seen as a heroic act, as another glorious page in the book of British history. But for many writers it contained nothing heroic; it was just noisy brandishing of weapons and useless loss of human lives.

  6. Ice bustles on quay piles : field studies and numerical simulations

    Energy Technology Data Exchange (ETDEWEB)

    Loset, S.; Marchenko, A. [Norwegian Univ. of Science and Technology, Trondheim (Norway)]|[Svalbard Univ. Centre, Spitsbergen (Norway)

    2008-07-01

    The additional gravity action created by the accumulation of ice on coastal structures and piles in cold climates may create a potential threat for the safety of the structures, particularly for mooring and fendering of floating structures and jacket-type structures. The gravity action is particularly critical in areas with changes in water level, such as large tide amplitudes. Ice bustle on piles may also increase the water line, thereby creating more horizontal action from moving ice fields. This study examined the growth and properties of ice bustles on quay piles in the Svea coal harbour, Spitsbergen during the winter and spring of 2007. Their formation was found to be related to super-cooling of piles relative to the temperature of surrounding water, when the heat conductivity of the pile material is higher than the heat conductivity of the water. Ice grows laterally from the surface of the pile at larger depths than the thickness of the surrounding level ice. The bustles are kept in place during water level changes because of the high adhesion between the ice and pile. The vertical and horizontal size of ice bustles formed on cylindrical quay steel piles in the study area was about 1.5 m with slightly downward sloping side walls. At high tide, the top surface coincided with the water level while at low tide, it was almost above the water surface. The Comsol Multiphysics 3.3a mathematical model was used to describe the formation of ice bustle around the cylindrical pile. Ice bustle growth was simulated with a constant water level while taking into consideration changes in tide and water level. This paper also described how the size of ice bustle is influenced by meteorological conditions, time and tidal amplitude. 1 refs., 1 tab., 10 figs.

  7. Analysis of static and dynamic pile-soil-jacket behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Azadi, Mohammad Reza Emami

    1998-12-31

    In the offshore industry, recent extreme storms, severe earthquakes and subsidence of the foundation of jacket platforms have shown that new models and methods must take into account the jacket- pile-soil foundation interaction as well as the non-linear dynamic performance/loading effects. This thesis begins with a review of the state of art pile-soil interaction model, recognizing that most existing pile-soil models have been established based on large diameter pile tests on specific sites. The need for site independent and mechanistic pile-soil interaction models led to the development of new (t-z) and (p-y) disk models. These are validated using the available database from recent large diameter pile tests in the North Sea and Gulf of Mexico. The established static disk models are applied for non-linear static analysis of the jacket-pile-soil system under extreme wave loading. Dynamic pile-soil interaction is studied and a new disk-cone model is developed for the non-linear and non-homogeneous soils. This model is applied to both surface and embedded disks in a soil layer with non-linear properties. Simplified non-linear as well as more complex analysis methods are used to study the dynamic response of the jacket platform under extreme sea and seismic loading. Ductility spectra analysis is introduced and used to study the dynamic performance of the jacket systems near collapse. Case studies are used to illustrate the effects of structural, foundation failure characteristics as well as dynamic loading effects on the overall performance of the jacket-pile-soil systems near ultimate collapse. 175 refs., 429 figs., 70 tabs.

  8. Optimising the bio-piling of weathered hydrocarbons within a risk management framework

    Energy Technology Data Exchange (ETDEWEB)

    Hough, R.; Brassington, K.; Sinke, A.; Crossley, J.; Paton, G.; Semple, K.; Risdon, G.; Jacobson, Ch.; Daly, P.; Jackman, S.; Lethbridge, G.; Pollard, S. [Cranfield Univ. (United Kingdom)

    2005-07-01

    Thirty years of research into petroleum microbiology and bio-remediation have bypassed an important observation - that many hydrocarbon contaminated sites posing potential risks to human health harbour weathered, 'mid-distillate' or heavy oils rather than 'fresh product'. Ex-situ bio-piling is an important technology for treating soils contaminated with weathered hydrocarbons. However, its performance continues to be represented by reference to reductions in the hydrocarbon 'load' in the soils being treated, rather than reductions in the risks posed by the hydrocarbon contamination. The absence of 'risk' from the vocabulary of many operators and remediation projects reduces stakeholder (regulatory, investor, landowner, and public) confidence in remediation technologies, and subsequently limits the market potential of these technologies. Stakeholder confidence in the bio-piling of weathered hydrocarbons may be improved by demonstrating process optimisation within a validated risk management framework. To address these issues, a consortium led by Cranfield University's Integrated Waste Management Centre has secured funding from the UK Government's Bio-remediation LINK programme. Project PROMISE (involving BP, SecondSite Regeneration Ltd., Dew Remediation Ltd., TES Bretby (Mowlem Group), technology translators PERA, and academics from Aberdeen, Cranfield and Lancaster Universities) aims to improve market confidence in bio-piling by demonstrating how this treatment may be applied within a risk management context. For weathered hydrocarbons in particular, the underpinning scientific components of process control, waste diagnostics, environmental fate modelling, and risk assessment have yet to be fully integrated to allow bio-piling projects to be verified with improved confidence. The Joint Research Council Review of Bio-remediation recognised this in calling explicitly for the positioning of bio-remediation within a

  9. Optimising the bio-piling of weathered hydrocarbons within a risk management framework

    International Nuclear Information System (INIS)

    Thirty years of research into petroleum microbiology and bio-remediation have bypassed an important observation - that many hydrocarbon contaminated sites posing potential risks to human health harbour weathered, 'mid-distillate' or heavy oils rather than 'fresh product'. Ex-situ bio-piling is an important technology for treating soils contaminated with weathered hydrocarbons. However, its performance continues to be represented by reference to reductions in the hydrocarbon 'load' in the soils being treated, rather than reductions in the risks posed by the hydrocarbon contamination. The absence of 'risk' from the vocabulary of many operators and remediation projects reduces stakeholder (regulatory, investor, landowner, and public) confidence in remediation technologies, and subsequently limits the market potential of these technologies. Stakeholder confidence in the bio-piling of weathered hydrocarbons may be improved by demonstrating process optimisation within a validated risk management framework. To address these issues, a consortium led by Cranfield University's Integrated Waste Management Centre has secured funding from the UK Government's Bio-remediation LINK programme. Project PROMISE (involving BP, SecondSite Regeneration Ltd., Dew Remediation Ltd., TES Bretby (Mowlem Group), technology translators PERA, and academics from Aberdeen, Cranfield and Lancaster Universities) aims to improve market confidence in bio-piling by demonstrating how this treatment may be applied within a risk management context. For weathered hydrocarbons in particular, the underpinning scientific components of process control, waste diagnostics, environmental fate modelling, and risk assessment have yet to be fully integrated to allow bio-piling projects to be verified with improved confidence. The Joint Research Council Review of Bio-remediation recognised this in calling explicitly for the positioning of bio-remediation within a risk management framework. The PERF report (Thermo

  10. Pile mixing increases greenhouse gas emissions during composting of dairy manure

    Science.gov (United States)

    The effect of pile mixing on greenhouse gas (GHG) emissions from stored dairy manure was determined using large flux chambers designed to completely cover pilot-scale manure piles. GHG emissions from piles that were mixed four times during the 80 day trial were about 20% higher than unmixed piles. ...

  11. 40 CFR 761.347 - First level sampling-waste from existing piles.

    Science.gov (United States)

    2010-07-01

    ... existing piles. 761.347 Section 761.347 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... from existing piles. (a) General. Sample piles that are either specifically configured for sampling... alternate sampling plan in accordance with § 761.62(c). (b) Specifically configured piles. A...

  12. Laboratory Testing of Cyclic Laterally Loaded Pile in Cohesionless Soil

    DEFF Research Database (Denmark)

    Roesen, Hanne Ravn; Ibsen, Lars Bo; Hansen, Mette;

    2013-01-01

    in the serviceability limit state. In this paper small-scale testing of a pile subjected to cyclic, lateral loading is treated in order to investigate the effect of cyclic loading. The test setup, which is an improvement of a previous setup, is described and the first results of testing are compared with previous......Offshore wind turbines are normally founded with large diameter monopiles and placed in rough environments subjected to variable lateral loads from wind and waves. A long-term lateral loading may create rotation (tilt) of the pile by change in the pile-soil system which is critical...

  13. Assessing the impact of pile driving upon fish

    OpenAIRE

    Hawkins, Anthony

    2005-01-01

    Pile driving associated with the removal and reconstruction of a jetty was monitored at a busy harbor in the North East of Scotland, adjacent to an important Atlantic salmon river. The main concern was with the impact of noise upon salmon migrating through the lower part of the river estuary. Pile driving was allowed to proceed subject to an agreed program of works to monitor sound levels and ensure least disturbance to salmon. Both percussive and vibratory pile driving took place. Sound-pres...

  14. The Influence of Time on Bearing Capacity of Driven Piles

    DEFF Research Database (Denmark)

    Jensen, J. Lysebjerg; Augustesen, A.; Sørensen, Carsten S.

    2004-01-01

    In Danish engineering practice, one of the ways to determine the ultimate bearing capacity of an axially loaded pile is by means of geostatic formulas. In the equation describing the contribution from the shaft friction to the total bearing capacity for piles located entirely or partly in clay......, a regeneration factor appears. The regeneration factor accounts for effects of dissipation of pore pressure due to pile driving and true time effects such as ageing on the ultimate bearing capacity. Normally the factor is 0.4 but in this paper, the influence of the undrained shear strength and time...

  15. Experimental investigation of a draft tube spouted bed for effects of geometric parameters on operation

    Science.gov (United States)

    Azizaddini, Seyednezamaddin; Lin, Weigang; Dam-Johansen, Kim

    2016-06-01

    Experiments are performed in a draft tube spouted bed (DTSB) to investigate effects of the operating conditions and the geometric parameters on the hydrodynamics. Geometry parameters, such as heights of the entrained zone, draft tube inner diameter, inner angle of the conical section were studied. Increasing the draft tube inner diameter, sharper inner angle of the conical section and higher height of entrained zone increase the internal solid circulation rate and the pressure drop. Even though, for all different configurations, higher gas feeding rate leads to higher internal solid circulation rate considering a maximum value.

  16. Experimental investigation of a draft tube spouted bed for effects of geometric parameters on operation

    DEFF Research Database (Denmark)

    Azizaddini, Seyednezamaddin; Lin, Weigang; Dam-Johansen, Kim

    2016-01-01

    Experiments are performed in a draft tube spouted bed (DTSB) to investigate effects of the operating conditions and the geometric parameters on the hydrodynamics. Geometry parameters, such as heights of the entrained zone, draft tube inner diameter, inner angle of the conical section were studied....... Increasing the draft tube inner diameter, sharper inner angle of the conical section and higher height of entrained zone increase the internal solid circulation rate and the pressure drop. Even though, for all different configurations, higher gas feeding rate leads to higher internal solid circulation rate...

  17. SPoRT: Transitioning NASA and NOAA Experimental Data to the Operational Weather Community

    Science.gov (United States)

    Jedlovec, Gary J.

    2013-01-01

    Established in 2002 to demonstrate the weather and forecasting application of real-time EOS measurements, the NASA Short-term Prediction Research and Transition (SPoRT) program has grown to be an end-to-end research to operations activity focused on the use of advanced NASA modeling and data assimilation approaches, nowcasting techniques, and unique high-resolution multispectral data from EOS satellites to improve short-term weather forecasts on a regional and local scale. With the ever-broadening application of real-time high resolution satellite data from current EOS, Suomi NPP, and planned JPSS and GOES-R sensors to weather forecast problems, significant challenges arise in the acquisition, delivery, and integration of the new capabilities into the decision making process of the operational weather community. For polar orbiting sensors such as MODIS, AIRS, VIIRS, and CRiS, the use of direct broadcast ground stations is key to the real-time delivery of the data and derived products in a timely fashion. With the ABI on the geostationary GOES-R satellite, the data volumes will likely increase by a factor of 5-10 from current data streams. However, the high data volume and limited bandwidth of end user facilities presents a formidable obstacle to timely access to the data. This challenge can be addressed through the use of subsetting techniques, innovative web services, and the judicious selection of data formats. Many of these approaches have been implemented by SPoRT for the delivery of real-time products to NWS forecast offices and other weather entities. Once available in decision support systems like AWIPS II, these new data and products must be integrated into existing and new displays that allow for the integration of the data with existing operational products in these systems. SPoRT is leading the way in demonstrating this enhanced capability. This paper will highlight the ways SPoRT is overcoming many of the challenges presented by the enormous data

  18. British Columbia inland oil spill response plan

    International Nuclear Information System (INIS)

    This paper presents an outline of the organization, procedures and duties of the provincial government in response to inland oil spills stemming from pipeline or tank-farm rupture, train derailment and vehicle accidents in British Columbia. Provincial response strategies were reviewed, along with their relationships to various policies and standards. Public, infrastructure and environmental protection were identified as key factors. Incident notification procedures were detailed, including outlines of roles, event criteria and call for incident management teams. Agreements and cost recovery issues were examined. The characteristics of site response were reviewed, including details of communications, tactical planning, and unified command among local and federal governments. The role of First Nations and responsible parties was also addressed. Details of shore cleanup, wildlife rescue, decontamination, and waste handling strategies were presented. The organization, missions and duties for an incident management team were outlined, along with a summary of operational guidelines and information on team positions and the establishment of joint information centres. The involvement of cooperating agencies was examined. An incident command system was also presented, including details of planning, operations, logistics, and organization. A checklist of individual duties was provided, with details of responsibilities, safety issues and general instructions for all team members. tabs., figs

  19. British Gas HICOM methanation process for SNG production

    Energy Technology Data Exchange (ETDEWEB)

    Ensell, R.L.; Stroud, H.J.F.

    1983-01-01

    The British Gas HICOM methanation process (formerly the HCM process) is an efficient, cost-effective way to make SNG from coal-derived gases. Using it with the British Gas/Lurgi slagging gasifier, for example, can yield coal-to-SNG thermal efficiencies of about 70%. In the HICOM process, a methane-rich gas is made directly from the purified gasifier product gas by reaction with steam over a catalyst; the temperature rise is controlled by hot-gas recycling and split-stream operation. The main attributes of this route are that it eliminates the CO-shift stage, has a high thermal efficiency, requires no selective sulfur removal system, minimizes waste liquor treatment, and has a low capital cost.

  20. Experimental methods to validate measures of emotional state and readiness for duty in critical operations.

    Energy Technology Data Exchange (ETDEWEB)

    Weston, Louise Marie

    2007-09-01

    A recent report on criticality accidents in nuclear facilities indicates that human error played a major role in a significant number of incidents with serious consequences and that some of these human errors may be related to the emotional state of the individual. A pre-shift test to detect a deleterious emotional state could reduce the occurrence of such errors in critical operations. The effectiveness of pre-shift testing is a challenge because of the need to gather predictive data in a relatively short test period and the potential occurrence of learning effects due to a requirement for frequent testing. This report reviews the different types of reliability and validity methods and testing and statistical analysis procedures to validate measures of emotional state. The ultimate value of a validation study depends upon the percentage of human errors in critical operations that are due to the emotional state of the individual. A review of the literature to identify the most promising predictors of emotional state for this application is highly recommended.

  1. Experimental methods to validate measures of emotional state and readiness for duty in critical operations

    International Nuclear Information System (INIS)

    A recent report on criticality accidents in nuclear facilities indicates that human error played a major role in a significant number of incidents with serious consequences and that some of these human errors may be related to the emotional state of the individual. A pre-shift test to detect a deleterious emotional state could reduce the occurrence of such errors in critical operations. The effectiveness of pre-shift testing is a challenge because of the need to gather predictive data in a relatively short test period and the potential occurrence of learning effects due to a requirement for frequent testing. This report reviews the different types of reliability and validity methods and testing and statistical analysis procedures to validate measures of emotional state. The ultimate value of a validation study depends upon the percentage of human errors in critical operations that are due to the emotional state of the individual. A review of the literature to identify the most promising predictors of emotional state for this application is highly recommended

  2. Experimental study of hydrodynamic and operation start of a baffled anaerobic reactor treating sewage

    Directory of Open Access Journals (Sweden)

    Ana Carolina Silveira Perico

    2009-12-01

    Full Text Available It is important to provide individual sanitation systems for sewage peri-urban communities or rural areas to minimize impacts on the environment and human health caused by sewage discharge in natura into water resources. In this context, the anaerobic digestion of effluent has been one of the main considered technologies due to easy implementation, material minimization and reduction in waste production. The objective of this work was to study a Baffled Anaerobic Reactor (BAR including its hydrodynamic characteristics, percentile of inoculum to be applied and reactor operation start. It was concluded that the flow is dispersed with 3.84% of dead spaces and that 20% of the cow manure provided best results; however, due to the high fiber content of the manure, its use is not recommended as inoculum. The BAR system, composed of four chambers, presented good performance for sewage treatment of a rural community in terms of organic substance removal (COD, turbidity and solids meeting effluent disposal standards of these parameters considering the Federal and Minas Gerais State legislation, in Brazil, even in a transient phase of operation, at temperatures below 20°C. However, the effluents from the BAR can’t be released into water bodies without other parameters such as nitrogen, phosphorus, fecal coliforms, and others are investigated to be conforming to those standards.

  3. Finite Element Investigations on the Interaction between a Pile and Swelling Clay

    DEFF Research Database (Denmark)

    Kaufmann, Kristine Lee; Nielsen, Benjaminn Nordahl; Augustesen, Anders Hust

    This paper aims to investigate the interaction between a pile and a swelling soil modelled as a cohesive soil subjected to unloading. The investigations include analyses of the heave of the excavation level, shear stresses at the soil–pile interface and internal pile forces based on a case study...... of Little Belt Clay. The case study involves a circular concrete pile installed in clay immediately after an excavation. The influence of the swelling soil on the soil–pile interaction and the internal pile forces are analysed by solely observing the upper pile part positioned in the swelling zone...

  4. The Experimental Investigation Of The Screen Operation In The Parametric Resonance Conditions

    Directory of Open Access Journals (Sweden)

    Bąk Łukasz

    2015-12-01

    Full Text Available In this paper the experimental studies of the screen working in the parametric resonance condition are discussed. The investigations are conducted for laboratory parametric resonance screen. The measuring test is performed for four cases of tension force values. The full sheet metal instead of the sieve is used. For each considered case the natural frequency of the plate and the parameter modulation frequency are determined. The achieved results are presented and discussed. It is shown that the highest sieve plate amplitude is obtained when the parameter modulation frequency is two times larger than natural frequency of the sieve plate. This parametric resonance vibration was observed only for tension force equal to 4000 N because of the rotational speed limits of electrical vibratos.

  5. Spin-selective recombination reactions of radical pairs: Experimental test of validity of reaction operators

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Kiminori [Department of Chemistry, University of Oxford, Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, Oxford (United Kingdom); Liddell, Paul; Gust, Devens [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona, 85287-1604 (United States); Hore, P. J. [Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, Oxford (United Kingdom)

    2013-12-21

    Spin-selective reactions of radical pairs are conventionally modelled using an approach that dates back to the 1970s [R. Haberkorn, Mol. Phys. 32, 1491 (1976)]. An alternative approach based on the theory of quantum measurements has recently been suggested [J. A. Jones and P. J. Hore, Chem. Phys. Lett. 488, 90 (2010)]. We present here the first experimental attempt to discriminate between the two models. Pulsed electron paramagnetic resonance spectroscopy has been used to investigate intramolecular electron transfer in the radical pair form of a carotenoid-porphyrin-fullerene molecular triad. The rate of spin-spin relaxation of the fullerene radical in the triad was found to be inconsistent with the quantum measurement description of the spin-selective kinetics, and in accord with the conventional model when combined with spin-dephasing caused by rotational modulation of the anisotropic g-tensor of the fullerene radical.

  6. Experimental study of the intra-operative radiation therapy for pancreatic cancer

    International Nuclear Information System (INIS)

    The radiosensitivity of pancreatic cancer, optimum dose of irradiation and the effect of 1-[4'-Hydroxy-2'-Butenoxy) Methyl]-2-Nitrosoimidaole (RK-28) on irradiation were investigated using an experimental pancreatic cancer of hamster and the following results were obtained: i) The mean lethal dose (Do) and the 50 % tumor control dose (TCD50) against the pancreatic cancer were 3.5 Gy and 73.7 ± 6.9 Gy, respectively. These results indicate that the pancreatic cancer is resistant to irradiation, which could be explained by the existence of hypoxic cells consisting of 35 % of the tumor. ii) The dose of intraoperative irradiation (10 - 40 Gy) seemed to be insufficient to bring long-term anti-tumor effect and long-term survival since that dose resulted in only temporary regression of the tumor. iii) The hypoxic cell sensitizer (RK28), which is known to specifically enhance the sensitivity of hypoxic cells to irradiation, lowered TCD50 of the pancreatic cancer to 53.8 ± 1.57 Gy. Therefore, RK-28 was effective in the treatment of the experimental pancreatic cancer (the enhancement ratio : 1.37). When combined with 30 or 40 Gy of irradiation, which is applicable to intraoperative irradiation, RK-28 induced a longer period of tumor suppression and a higher tumor regression ratio than irradiation alone. These results indicate that RK-28 significantly increases the effect of intraoperative irradiation and this combination therapy could possibly induce remarkable effect on tumor regression and long-term survival. (author)

  7. Numerical Simulation for the Soil-Pile-Structure Interaction under Seismic Loading

    Directory of Open Access Journals (Sweden)

    Lifeng Luan

    2015-01-01

    Full Text Available Piles are widely used as reinforcement structures in geotechnical engineering designs. If the settlement of the soil is greater than the pile, the pile is pulled down by the soil, and negative friction force is produced. Previous studies have mainly focused on the interaction of pile-soil under static condition. However, many pile projects are located in earthquake-prone areas, which indicate the importance of determining the response of the pile-soil structure under seismic load. In this paper, the nonlinear, explicit, and finite difference program FLAC3D, which considers the mechanical behavior of soil-pile interaction, is used to establish an underconsolidated soil-pile mode. The response processes of the pile side friction force, the pile axial force, and the soil response under seismic load are also analyzed.

  8. Operator- and software-related post-experimental variability and source of error in 2-DE analysis.

    Science.gov (United States)

    Millioni, Renato; Puricelli, Lucia; Sbrignadello, Stefano; Iori, Elisabetta; Murphy, Ellen; Tessari, Paolo

    2012-05-01

    In the field of proteomics, several approaches have been developed for separating proteins and analyzing their differential relative abundance. One of the oldest, yet still widely used, is 2-DE. Despite the continuous advance of new methods, which are less demanding from a technical standpoint, 2-DE is still compelling and has a lot of potential for improvement. The overall variability which affects 2-DE includes biological, experimental, and post-experimental (software-related) variance. It is important to highlight how much of the total variability of this technique is due to post-experimental variability, which, so far, has been largely neglected. In this short review, we have focused on this topic and explained that post-experimental variability and source of error can be further divided into those which are software-dependent and those which are operator-dependent. We discuss these issues in detail, offering suggestions for reducing errors that may affect the quality of results, summarizing the advantages and drawbacks of each approach. PMID:21394601

  9. Developing Tele-Operated Laboratories for Manufacturing Engineering Education. Platform for E-Learning and Telemetric Experimentation (PeTEX

    Directory of Open Access Journals (Sweden)

    A. Erman Tekkaya

    2010-09-01

    Full Text Available The aim of the PeTEX-project is to establish an e-Learning platform for the development, implementation, and delivery of educational training programs in the field of manufacturing engineering. The PeTEX team designs both: a technical platform for eLearning based on “Moodle” including distributed tele-operated experimentation facilities, and didactic and socio-technical requirements for a successful online learning community. User interfaces are deployed for remote access to instruments, data analysis and multiplexed data access via network protocols. Hence, the platform provides complex tools in order to perform various activities to support the educational process, from telemetric experimentation to virtual project groups for an entire community to the purpose of domain specific learning. This paper describes important steps of interdisciplinary participatory design and development of a remote lab-prototype in the field of manufacturing engineering.

  10. Steady state heat transfer experimental studies of LHC superconducting cables operating in cryogenic environment of superfluid helium

    CERN Document Server

    Santandrea, Dario; Tuccillo, Raffaele; Granieri, Pier Paolo

    The heat management is a basic and fundamental aspect of the superconducting magnets used in the CERN Large Hadron Collider. Indeed, the coil temperature must be kept below the critical value, despite the heat which can be generated or deposited in the magnet during the normal operations. Therefore, this thesis work aims at determining the heating power which can be extracted from the superconducting cables of the LHC, specially through their electrical insulation which represents the main thermal barrier. An experimental measurement campaign in superfluid helium bath was performed on several samples reproducting the main LHC magnets. The heating power was generated in the sample by Joule heating and the temperature increase was measured by means of Cernox bare chip and thermocouples. An innovative instrumentation technique which also includes the in-situ calibration of the thermocouples was developed. A thorough uncertainty analysis on the overall measurement chain concluded the experimental setup. The prese...

  11. EL3 reactor description and safety analysis report; Pile EL3, rapport descriptif et de surete

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1969-02-01

    The EL-3 reactor is an experimental pile. Heterogenous type reactor, water moderated and cooled it uses slightly enriched uranium oxide as fuel (4.5 percent) distributed in vertical cells that constitute the core (the maximum number of cells is 99). It is conceived to function at a maximal thermal power of 20 MW. It supplies a maximum thermal neutron flux of 10{sup 14} neutrons/cm{sup 2}/sec. It has several experimental devices. The EL-3 reactor is surrounded by auxiliary circuits of fluids, in a sealed containment, slightly depressed. The primary heavy water coolant circuit is completely included in this containment. Its cooling is made by the intermediary of a light water secondary circuit by atmospheric refrigerants. The ventilation circuits of the sealed containment and the reactor block do not release air outside, under nornal functioning, by a particularly studied chimney only after filtering and eventually dilution. The eventual contamination of the light water or air by active products is permanently monitored to allow the reactor shutdown and avoid the release in atmosphere of dangerous products. The EL-3 reactor, laying down in may 1955, has diverged in july 1957, made its first ascending in power in december 1957 and reached its complete power in april 1958. The positioning of actual fuel (snow crystal) was made during summer 1964. Reactor with an experimental aim, it is used for theoretical and technological studies by material irradiation in the experimental channels and the core cells, with possibilities to constitute independent loops (relative to the cooling fluids). Thirty vertical channels are devoted to the fabrication of artificial radioelements. [French] La pile EL-3 est une pile experimentale. Du type heterogene, moderee et refroidie a l'eau lourde elle utilise comme combustible de l'oxygene d'uranium faiblement enrichi (4,5 p.cent) reparti en cellules verticales qui constituent le coeur (le nombre maximal de cellules est de, 99

  12. Experimental Research of Variable Operating Performance on Water Source Multi-Connected Air-Conditioning System with Digital Scroll Compressor

    OpenAIRE

    Xingwang Zhu; Xueli Nie; Yanli Lv; Chaoxin Wang; Yugui Su

    2013-01-01

    In this study, we study the water source heat pump and digital scroll compressor and experimentally in the multi-connected air-conditioning system. Variable performance is developed when the unit operates in refrigerating and heating mode. The maximum of refrigerating capacity is 36519.95W when inlet water temperature of the condenser is 30°C and dry-bulb temperature of indoor air is 32°C, at the same time the maximum of EER is 4.33 when inlet water temperature of the condenser is 20°C and dr...

  13. Pre-operational integrated pressure tests at EMO NPP (VVER 440/V 213) and options for their experimental utilization

    International Nuclear Information System (INIS)

    Pre-operational integrated leakage rate and structural integrity tests for the Mochovce NPP are discussed. A programme is presented of experiments proposed during these tests, to be used in investigations of the following phenomena: water drop entrainment from the water pool into the air trap; hydraulic resistance and leaktightness of check valve DN 500; performance of valves DN 250; response of bubble condenser walls to loading; phenomenology of the whole process and verification of some partial analytical and experimental procedures. (Z.S.) 2 figs

  14. PileLine: a toolbox to handle genome position information in next-generation sequencing studies

    Directory of Open Access Journals (Sweden)

    Fdez-Riverola Florentino

    2011-01-01

    Full Text Available Abstract Background Genomic position (GP files currently used in next-generation sequencing (NGS studies are always difficult to manipulate due to their huge size and the lack of appropriate tools to properly manage them. The structure of these flat files is based on representing one line per position that has been covered by at least one aligned read, imposing significant restrictions from a computational performance perspective. Results PileLine implements a flexible command-line toolkit providing specific support to the management, filtering, comparison and annotation of GP files produced by NGS experiments. PileLine tools are coded in Java and run on both UNIX (Linux, Mac OS and Windows platforms. The set of tools comprising PileLine are designed to be memory efficient by performing fast seek on-disk operations over sorted GP files. Conclusions Our novel toolbox has been extensively tested taking into consideration performance issues. It is publicly available at http://sourceforge.net/projects/pilelinetools under the GNU LGPL license. Full documentation including common use cases and guided analysis workflows is available at http://sing.ei.uvigo.es/pileline.

  15. Experimental Research of Variable Operating Performance on Water Source Multi-Connected Air-Conditioning System with Digital Scroll Compressor

    Directory of Open Access Journals (Sweden)

    Xingwang Zhu

    2013-05-01

    Full Text Available In this study, we study the water source heat pump and digital scroll compressor and experimentally in the multi-connected air-conditioning system. Variable performance is developed when the unit operates in refrigerating and heating mode. The maximum of refrigerating capacity is 36519.95W when inlet water temperature of the condenser is 30°C and dry-bulb temperature of indoor air is 32°C, at the same time the maximum of EER is 4.33 when inlet water temperature of the condenser is 20°C and dry-bulb temperature of indoor air is 27°C. The unit operates in heating mode, the maximum of heating capacity and EER is 33275.73W and 3.86 when inlet water temperature of the condenser is 30°C and dry-bulb temperature of indoor air is 20°C.

  16. The Results of Experimental Investigation Recycling Meat and Plant Waste in the Periodic Operation Bioreactor

    Directory of Open Access Journals (Sweden)

    Antonas Misevičius

    2011-12-01

    Full Text Available Waste is unwanted materials that are mainly the result of human activities and one of the sources of environmental pollution. An increase in the world’s population causes a growth in the amounts of waste in the modern world. Every year, the increasing quantities of waste are the major problems these days; therefore, calls for taking effective measures to tackle this problem could be effective tools. The article presents the results of experimental studies on using meat waste and their mixes with herbal waste. The conducted experiments observed the concentrations of methane, hydrogen sulphide and oxygen under periodic mesophilic conditions in the bioreactor. Research has shown that the use of herbal supplements with meat waste produces better results than using only meat waste. The digestion of meat wastes points to an average amount of biogas which is 0.5 m3/m3d, that of meat and herbal waste mixture (19:1 – 0.51 m3/m3d, meat and herbal waste mixture (9:1 – 0.56 m3/m3d. The content of biogas methane was 0.074 m3/m3d, 0.083 m3/m3d, 0.101 m3/m3d respectively.Article in Lithuanian

  17. Experimental study of ELM-like heat loading on beryllium under ITER operational conditions

    Science.gov (United States)

    Spilker, B.; Linke, J.; Pintsuk, G.; Wirtz, M.

    2016-02-01

    The experimental fusion reactor ITER, currently under construction in Cadarache, France, is transferring the nuclear fusion research to the power plant scale. ITER’s first wall (FW), armoured by beryllium, is subjected to high steady state and transient power loads. Transient events like edge localized modes not only deposit power densities of up to 1.0 GW m-2 for 0.2-0.5 ms in the divertor of the machine, but also affect the FW to a considerable extent. Therefore, a detailed study was performed, in which transient power loads with absorbed power densities of up to 1.0 GW m-2 were applied by the electron beam facility JUDITH 1 on beryllium specimens at base temperatures of up to 300 °C. The induced damage was evaluated by means of scanning electron microscopy and laser profilometry. As a result, the observed damage was highly dependent on the base temperatures and absorbed power densities. In addition, five different classes of damage, ranging from ‘no damage’ to ‘crack network plus melting’, were defined and used to locate the damage, cracking, and melting thresholds within the tested parameter space.

  18. Computerised analysis of sulphate action on model concrete piles

    Digital Repository Service at National Institute of Oceanography (India)

    Deshmukh, A.M.; Balasubramanian, S.; Venugopal, C.

    Sulphate action severely affects the durability of marine structures. It is imperative to study precisely the effects of magnesium sulphate on pile foundations in the marine environment. In the present paper an attempt is made to assess and analyse...

  19. 20051655 - Petronas, Capacity of Driven Piles Offshore Malaysia

    DEFF Research Database (Denmark)

    Augustesen, Anders; Andersen, Lars

    This document is the third of four notes concerning the vertical capacity of piles. It includes an assessment of the effect of previous static load testing upon the measured capacity, i.e. preshearing effects....

  20. 20051655 - Petronas, Capacity of Driven Piles Offshore Malaysia

    DEFF Research Database (Denmark)

    Augustesen, Anders

    This document is the second of four notes concerning the effects of time (in this case ageing) on the vertical capacity of piles. It includes a critical review of the relevant publications described in note a....

  1. As Traffic Piles Up, So Does Air Pollution

    Science.gov (United States)

    ... 160914.html As Traffic Piles Up, So Does Air Pollution To minimize exposure, researchers recommend shutting windows and ... Doing so can reduce your exposure to toxic air pollution from a traffic jam by up to 76 ...

  2. Lateral response of pile foundations in liquefiable soils

    Directory of Open Access Journals (Sweden)

    Asskar Janalizadeh

    2015-10-01

    Full Text Available Liquefaction has been a main cause of damage to civil engineering structures in seismically active areas. The effects of damage of liquefaction on deep foundations are very destructive. Seismic behavior of pile foundations is widely discussed by many researchers for safer and more economic design purposes. This paper presents a pseudo-static method for analysis of piles in liquefiable soil under seismic loads. A free-field site response analysis using three-dimensional (3D numerical modeling was performed to determine kinematic loads from lateral ground displacements and inertial loads from vibration of the superstructure. The effects of various parameters, such as soil layering, kinematic and inertial forces, boundary condition of pile head and ground slope, on pile response were studied. By comparing the numerical results with the centrifuge test results, it can be concluded that the use of the p-y curves with various degradation factors in liquefiable sand gives reasonable results.

  3. Airborne thermography of temperature patterns in sugar beet piles

    Science.gov (United States)

    Moore, D. G.; Bichsel, S.

    1975-01-01

    An investigation was conducted to evaluate the use of thermography for locating spoilage areas (chimneys) within storage piles and to subsequently use the information for the scheduling of their processing. Thermal-infrared quantitative scanner data were acquired initially on January 16, 1975, over the storage piles at Moorhead, Minnesota, both during the day and predawn. Photographic data were acquired during the day mission to evaluate the effect of uneven snow cover on the thermal emittance, and the predawn thermography was used to locate potential chimneys. The piles were examined the day prior for indications of spoilage areas, and the ground crew indicated that no spoilage areas were located using their existing methods. Nine spoilage areas were interpreted from the thermography. The piles were rechecked by ground methods three days following the flights. Six of the nine areas delineated by thermography were actual spoilage areas.

  4. Residual settlement calculation of geocell cushion over gravel piles

    Institute of Scientific and Technical Information of China (English)

    陈昌富; 杨宇; 肖淑君; 周志军

    2008-01-01

    The calculation of residual settlement of bidirectional reinforced composite foundation, which is composed of geocell cushion over gravel piles, was studied. The geocell cushion was modeled as a thin flexible plate with large deflection. Based on the Kirchhoff hypothesis, the governing differential equations and boundary conditions of the deformation of geocell cushion under working load were founded using von Karman method and solved by Galerkin method. On theses bases, the gravel piles and inter-pile soils were assumed as Winkler ground with variable spring stiffness so as to execute the approximate calculation of the residual settlement of the bidirectional reinforced composite foundation. The calculation method was verified by two laboratory experiments concerning settlement of embankments. One experiment was with just geocell cushion installed to treat the soft clay under embankments; another one was with both geocell cushion and gravel piles installed. The results show that the calculated settlement curve and the maximum settlement are closed to the observed ones.

  5. Piles, Tabs and Overlaps in Navigation among Documents

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper Anders Søren

    2010-01-01

    Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles. In an experim......Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles....... In an experiment we compared 11 participants’ navigation with these variations and found strong task effects. Overall, overlapping windows were preferred and their structured layout worked well with some tasks. Surprisingly, tabbed documents were efficient in tasks requiring simply finding a document. Piled...... on document navigation and its support by piling....

  6. Interpretation of the TRADE In-Pile source multiplication experiments

    Science.gov (United States)

    Mercatali, Luigi; Carta, Mario; Peluso, Vincenzo

    2006-06-01

    Within the framework of the neutronic characterization of the TRIGA RC-1 reactor in support to the TRADE (TRiga Accelerator Driven Experiment) program, the interpretation of the subcriticality level measurements performed in static regime during the TRADE In-Pile experimental program is presented. Different levels of subcriticality have been measured using the MSA (Modified Source Approximated) method by the insertion of a standard fixed radioactive source into different core positions. Starting from a reference configuration, fuel elements were removed: control rods were moved outward as required for the coupling experiments envisioned with the proton accelerator and fission chambers were inserted in order to measure subcritical count rates. A neutron-physics analysis based on the modified formulation of the source multiplication method (MSM) has been carried out, which requires the systematic solution for each experimental configuration of the homogeneous, both in the forward and adjoint forms, and inhomogeneous Boltzmann equations. By means of such a methodology calculated correction factors to be applied to the MSA measured reactivities were produced in order to take into account spatial and energetic effects creating changes in the detector efficiencies and effective source with respect to the calibration configuration. The methodology presented has been tested against a large number of experimental states. The measurements have underlined the sensitivity of the MSA measured reactivities to core geometry changes and control rod perturbations; the efficiency of MSM factors to dramatically correct for this sensitivity is underlined, making of this technique a relevant methodology in view of the incoming US RACE program to be performed in TRIGA reactors.

  7. An experimental investigation of the air entrainment in the shutdown cooling system during mid-loop operation

    International Nuclear Information System (INIS)

    An experimental study on the air entrainment phenomena during mid-loop operation has been performed for Ulchin 3 and 4 nuclear power plant (UCN 3 and 4). The UCN 3 and 4 is the standard Combustion Engineering (CE) System 80, two-loop, 2825 MWt pressurized water reactor which is currently under construction in Korea. This study was undertaken by Korea Atomic Energy Research Institute to provide a basis for modification of CE system 80 design which has relatively small mid-loop operating range, and to investigate the impact of the air entrainment on the shutdown cooling pump. A 1/4 scale model test was performed for two shutdown cooling suction nozzle configurations, with and without bellmouth entry, to obtain data relative to air ingestion and vortex formation at the shutdown cooling suction nozzle during mid-loop operation. The test model size was determined based on Froude number corresponding to that which occurs in plants by considering that the Weber number and Reynolds number are large enough to ensure that liquid surface tension and viscosity would not significantly affect the vortex formation. An empirical correlation between the flow rate and the critical submergence was obtained with respect to the Froude number. The impact of the air entrainment of the pump was also investigated to select parameters for plant operators to monitor the onset of air entrainment into shutdown cooling system (SCS). Effects of the bellmouth entry on the critical submergence were also investigated. (author)

  8. Processing Satellite Imagery To Detect Waste Tire Piles

    Science.gov (United States)

    Skiles, Joseph; Schmidt, Cynthia; Wuinlan, Becky; Huybrechts, Catherine

    2007-01-01

    A methodology for processing commercially available satellite spectral imagery has been developed to enable identification and mapping of waste tire piles in California. The California Integrated Waste Management Board initiated the project and provided funding for the method s development. The methodology includes the use of a combination of previously commercially available image-processing and georeferencing software used to develop a model that specifically distinguishes between tire piles and other objects. The methodology reduces the time that must be spent to initially survey a region for tire sites, thereby increasing inspectors and managers time available for remediation of the sites. Remediation is needed because millions of used tires are discarded every year, waste tire piles pose fire hazards, and mosquitoes often breed in water trapped in tires. It should be possible to adapt the methodology to regions outside California by modifying some of the algorithms implemented in the software to account for geographic differences in spectral characteristics associated with terrain and climate. The task of identifying tire piles in satellite imagery is uniquely challenging because of their low reflectance levels: Tires tend to be spectrally confused with shadows and deep water, both of which reflect little light to satellite-borne imaging systems. In this methodology, the challenge is met, in part, by use of software that implements the Tire Identification from Reflectance (TIRe) model. The development of the TIRe model included incorporation of lessons learned in previous research on the detection and mapping of tire piles by use of manual/ visual and/or computational analysis of aerial and satellite imagery. The TIRe model is a computational model for identifying tire piles and discriminating between tire piles and other objects. The input to the TIRe model is the georeferenced but otherwise raw satellite spectral images of a geographic region to be surveyed

  9. Mate choice and the operational sex ratio: an experimental test with robotic crabs.

    Science.gov (United States)

    Hayes, C L; Callander, S; Booksmythe, I; Jennions, M D; Backwell, P R Y

    2016-07-01

    The operational sex ratio (OSR: sexually active males: receptive females) predicts the intensity of competition for mates. It is less clear, however, under what circumstances, the OSR predicts the strength of sexual selection - that is, the extent to which variation in mating success is attributable to traits that increase the bearer's attractiveness and/or fighting ability. To establish causality, experiments that manipulate the OSR are required. Furthermore, if it is possible to control for any OSR-dependent changes in the chosen sex (e.g. changes in male courtship), we can directly test whether the OSR affects the behaviour of the choosing sex (e.g. female choice decisions). We conducted female mate choice experiments in the field using robotic models of male fiddler crabs (Uca mjoebergi). We used a novel design with two females tested sequentially per trial. As in nature, the choice of the first female to mate therefore affected the mates available to the next female. In general, we detected significant sexual selection due to female choice for 'males' with larger claws. Importantly, the strength of sexual selection did not vary across five different OSR/density treatments. However, as the OSR decreased (hence the number of available males declined), females chose the 'males' with the largest claws available significantly more often than expected by chance. Possible reasons for this mismatch between the expected and observed effects of the OSR on the strength of sexual selection are discussed. PMID:27087241

  10. Golden Herbs used in Piles Treatment: A Concise Report

    OpenAIRE

    Rajani Chauhan; Km. Ruby; Jaya Dwivedi

    2012-01-01

    Herbal medicine is also called phytomedicine. It is refers to using a plant's seeds, berries, roots, leaves, bark, or flowers for disease treatment.Herbs have many golden phytochemicals or secondary metabolites to treat disease. They have a long tradition of use outside of conventional medicine. Hemorrhoids or Piles treatment through Herbs has been effective and a golden treatment without any side-effects. There are some herbs which is useful in piles treatment such as Aesculus hippocastanum,...

  11. THE NEW STRUCTURE OF A PLATE-PILE FOUNDATION

    Directory of Open Access Journals (Sweden)

    SAMORODOV О. V.

    2016-01-01

    Full Text Available Raising of problem. In the construction of high-rise buildings with significant loads on foundations and bedding at the base of not rocky soils tend to use the most common pile foundation to reduce the deformation and correspond to regulations [1] on the maximum permissible deformation. Monitoring of the stress-strain state (SSS pile foundations constructed buildings shows the existing reserves of bearing capacity on the one hand - soil bases of the second group of limit states, on the other - the foundation of the first group of limit states by regulating the SSS foundation during construction and exploitation. Therefore, are increasingly using more progressive structure of foundations consisting of piles and of plate, as well as methods for their construction [2 - 10], however, in their design there are a number of disadvantages associated with the ambiguity of the application of methods for the calculation of such structures, which allows to do only partial conclusions and recommendations. Purpose. Is proposing the new structure of a plate-pile foundation, which overcomes the drawbacks of the existing design solutions and methods of consruction their, as well as is proposing an engineering method of a determination of basic parameters. Conclusion. Is proposes the new structure of a plate-pile foundation and the method of a determination of basic parameters his in the design of a soil base to the maximum permissible deformation Su buildings. Efficiency of application this type plate-pile foundation obtained by rational distribution resistance between a plate and piles, when under load from the building to the first work fully incorporated plate that allows maximum deformed for plate, and then the piles - due to of the hinge connection with the plate. Thus, depending on the maximum permissible deformation for buildings resistance of plate part of a full load of more than 50%, that significantly reduces the consumption of concrete.

  12. Jointless and Smoother Bridges: Behavior and Design of Piles

    OpenAIRE

    Frosch, Robert J; Chovichien, Voraniti; Durbin, Katrinna; Fedroff, David

    2006-01-01

    Integral abutment bridges have been used in the United States for decades. By eliminating expensive expansion joints, the piles supporting the end bent accommodate the total thermal movement of the bridge. Currently, integral bridges are designed based upon experience, and a rational design specification has not been developed. Furthermore, the interaction of the abutment, pile, and soil remains uncertain. A better understanding regarding the behavior of this system is needed. The objective o...

  13. Axial Non-linear Dynamic Soil-Pile Interaction - Keynote

    OpenAIRE

    Holeyman A.; Whenham V.

    2014-01-01

    This keynote lecture describes recent analytical and numerical advances in the modeling of the axial nonlinear dynamic interaction between a single pile and its embedding soil. On one hand, analytical solutions are developed for assessing the nonlinear axial dynamic response of the shaft of a pile subjected to dynamic loads, and in particular to vibratory loads. Radial inhomogeneity arising from shear modulus degradation is evaluated over a range of parameters and compared with those obtained...

  14. Review of the literature on leachates from coal storage piles

    Energy Technology Data Exchange (ETDEWEB)

    Davis, E.C.; Boegly, W.J. Jr.

    1978-01-01

    Runoff from coal storage piles associated with coal conversion or combustion facilities may represent a potential source of environmental pollution. This report is an assessment of existing information on coal pile leachate. The assessment indicates that few detailed studies have been conducted to date, and these are limited and the results are highly variable. More detailed long-range studies using various types of coal are recommended. These studies should be carried out both in the laboratory and in field-scale experiments.

  15. In-pile test of Qinshan PWR fuel bundle

    International Nuclear Information System (INIS)

    In-pile test of Qinshan Nuclear Power Plant PWR fuel bundle has been conducted in HWRR HTHP Test loop at CIAE. The test fuel bundle was irradiated to an average burnup of 25000 Mwd/tU. The authors describe the structure of (3 x 3-2) test fuel bundle, structure of irradiation rig, fuel fabrication, irradiation conditions, power and fuel burnup. Some comments on the in-pile performance for fuel bundle, fuel rod and irradiation rig were made

  16. Guidelines for the Protection of Steel Piles : Corrosive Marine Environment

    OpenAIRE

    Rhodes, Graham

    2011-01-01

    The corrosion of steel is a common phenomenon. In a marine environment, steel is corroded at an accelerated rate due to the atmospheric conditions. To combat this corrosion, steel piles are coated in order to protect them. As a major supplier of steel piles, Rautaruukki Oyj (Ruukki) commissioned this project in order to streamline their coating process. Currently Ruukki supplies a different coating system for almost every job; the aim of the project was to reduce the number of systems used to...

  17. Pile Structure Program, Projected Start Date : January 1, 2010 (Implementation).

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Chris; Corbett, Catherine [Lower Columbia River Estuary Partnership; Ebberts, Blaine [U.S. Army Corps of Engineers

    2009-07-27

    The 2008 Federal Columbia River Power System Biological Opinion includes Reasonable and Prudent Alternative 38-Piling and Piling Dike Removal Program. This RPA directs the Action Agencies to work with the Estuary Partnership to develop and implement a piling and pile dike removal program. The program has since evolved to include modifying pile structures to enhance their habitat value and complexity by adding large woody debris. The geographic extent of the Pile Structure Program (PSP) includes all tidally-influenced portions of the lower Columbia River below Bonneville Dam; however, it will focus on the mainstem. The overarching goal of the PSP is to enhance and restore ecosystem structure and function for the recovery of federally listed salmonids through the active management of pile structures. To attain this goal, the program team developed the following objectives: (1) Develop a plan to remove or modify pile structures that have lower value to navigation channel maintenance, and in which removal or modification will present low-risk to adjacent land use, is cost-effective, and would result in increased ecosystem function. (2) Determine program benefits for juvenile salmonids and the ecosystem through a series of intensively monitored pilot projects. (3) Incorporate best available science and pilot project results into an adaptive management framework that will guide future management by prioritizing projects with the highest benefits. The PSP's hypotheses, which form the basis of the pilot project experiments, are organized into five categories: Sediment and Habitat-forming Processes, Habitat Conditions and Food Web, Piscivorous Fish, Piscivorous Birds, and Toxic Contaminant Reduction. These hypotheses are based on the effects listed in the Estuary Module (NOAA Fisheries in press) and others that emerged during literature reviews, discussions with scientists, and field visits. Using pilot project findings, future implementation will be adaptively managed

  18. Comparing dynamic and static test results of bored piles

    OpenAIRE

    Long, Michael

    2007-01-01

    Due to increasing time, cost and transportation difficulties, Irish contractors are seeking an alternative to conventional static pile load tests. As a result several firms have adopted dynamic testing techniques to supplement and in some cases to replace conventional static tests. In order to assess the reliability of the systems and to address the concerns of owners and consulting engineers, a database comprising 43 pairs of static and dynamic tests on piles from 24 sites aro...

  19. Installation of a mono pile as a foundation structure of a tidal turbine; Installation eines Monopfahls als Gruendungsstruktur fuer eine Gezeitenturbine

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Stefan [BAUER Spezialtiefbau GmbH, Schrobenhausen (Germany). Bautechnik; Bauer, Thomas [BAUER AG, Schrobenhausen (Germany)

    2012-11-01

    Tidal turbines enable a power generation from the flow energy of the sea. Usually heavy weight structures are used for the foundation of tidal turbines. However, these heavy weight structures are not fixed to the bottom of the sea. A mono pile being embedded in the bottom of the sea is an alternative which is a significant benefit for operators of tidal turbine operator.

  20. Hanford Atomic Products Operation monthly report for March 1956

    Energy Technology Data Exchange (ETDEWEB)

    1956-04-20

    This is the monthly report for the Hanford Laboratories Operation, March, 1956. Metallurgy, reactor fuels, chemistry, dosimetry, separation processes, reactor technology; financial activities, visits, biology operation, physics and instrumentation research, employee relations, pile technology, safety and radiological sciences are discussed.

  1. Slime thickness evaluation of bored piles by electrical resistivity probe

    Science.gov (United States)

    Chun, Ok-Hyun; Yoon, Hyung-Koo; Park, Min-Chul; Lee, Jong-Sub

    2014-09-01

    The bottoms of bored piles are generally stacked with soil particles, both while boreholes are being drilled, and afterward. The stacked soils are called slime, and when loads are applied on the pile, increase the pile settlement. Thus to guarantee the end bearing capacity of bored piles, the slime thickness should be precisely detected. The objective of this study is to suggest a new method for evaluating the slime thickness, using temperature compensated electrical resistivity. Laboratory studies are performed in advance, to estimate and compare the resolution of the electrical resistivity probe (ERP) and time domain reflectometry (TDR). The electrical properties of the ERP and TDR are measured using coaxial type electrodes and parallel type two-wire electrodes, respectively. Penetration tests, conducted in the fully saturated sand-clay mixtures, demonstrate that the ERP produces a better resolution of layer detection than TDR. Thus, field application tests using the ERP with a diameter of 35.7 mm are conducted for the investigation of slime thickness in large diameter bored piles. Field tests show that the slime layers are clearly identified by the ERP: the electrical resistivity dramatically increases at the interface between the slurry and slime layer. The electrical resistivity in the slurry layer inversely correlates with the amount of circulated water. This study suggests that the new electrical resistivity method may be a useful method for the investigation of the slime thickness in bored piles.

  2. Axial Non-linear Dynamic Soil-Pile Interaction - Keynote

    Directory of Open Access Journals (Sweden)

    Holeyman A.

    2014-01-01

    Full Text Available This keynote lecture describes recent analytical and numerical advances in the modeling of the axial nonlinear dynamic interaction between a single pile and its embedding soil. On one hand, analytical solutions are developed for assessing the nonlinear axial dynamic response of the shaft of a pile subjected to dynamic loads, and in particular to vibratory loads. Radial inhomogeneity arising from shear modulus degradation is evaluated over a range of parameters and compared with those obtained by other authors and by a numerical radial discrete model simulating the pile and soil movements from integration of the laws of motion. New approximate non linear solutions for axial pile shaft behaviour developed from general elastodynamic equations are presented and compared to existing linear solutions. The soil non linear behaviour and its ability to dissipate mechanical energy upon cyclic loading are shown to have a significant influence on the mechanical impedance provided by the surrounding soil against pile shaft movement. The limitations of over-simplified modelling of pile response are highlighted.

  3. The Effects of Time on Soil Behaviour and Pile Capacity

    DEFF Research Database (Denmark)

    Augustesen, Anders

    this into account. This implies that the design methods used today do not in general make use of the full capacity of piles. This thesis is based on a number of scientific papers and reports that deal with elements of pile design and time effects in soils in general. With regard to pile design, focus is placed...... on estimation of the axial pile capacity by static design equations and especially the influence of time on pile capacity. In respect of time effects in soils in general focus is placed on observed time-dependent behaviour of soils and models developed to capture this behaviour. The thesis consists of two parts...... based on a set of static loading tests. In the literature it is suggested that the pile capacity increases with the logarithm to time after installation which is confirmed in this thesis. In continuation of this, it is analysed whether the magnitude of the set-up is related to the properties of the clay...

  4. Experimental Research on Comparison of High Strain Dynamic Testing and Static Loading Test on Vertical Bearing Capacity for Large Diameter Manual Hole Digging Pile%大直径人工挖孔桩竖向承载力动静对比试验研究

    Institute of Scientific and Technical Information of China (English)

    洪辉煌

    2015-01-01

    在介绍静载荷试验和高应变法的基础上,结合工程实例对它们的检测结果进行对比,由此检验高应变法检测大直径人工挖孔桩的精度.%Based on the introduction of high strain dynamic testing and static loading test,and combined with the engineering example,the testing results were compared in this paper. Thereout,it could check up the testing precision of high strain dynamic testing on large diameter manual hole digging pile.

  5. Hybrid photovoltaic/diesel green ship operating in standalone and grid-connected mode – Experimental investigation

    International Nuclear Information System (INIS)

    This paper presents the experimental results from the operation of a proto-type green ship in Geoje island, South Korea. As Korea is a peninsula situated between the continent and the sea, its location is ideal for utilizing PV/diesel green ship. After ground testing with a stand-alone PV (photovoltaic) generation system, this PV system was added to a conventional diesel ship. The proto-type green ship consisted of a photovoltaic (PV) generation system, diesel engine, battery energy storage, hybrid control system, and a stand-alone and grid-connected inverter. The aim of the green ship was not only to minimize fuel consumption but also to support the power grid as DG (distributed generation) connected to the smart grid (in land) and micro-grid (in island) in the near future. At the end of this paper, environmental, economic and sensitivity analysis would be discussed mainly based on experimental results. -- Highlights: ► The hybrid PV/diesel green ship operates not only in a stand-alone mode but also when connected to a smart grid. ► The hybrid PV/diesel green ship passed the stability assessment test by the authorized department. ► The payback period of initial investment can be reduced due to the decreasing PV module costs, increasing diesel fuel costs. ► The proposed green ship will decrease the dependence on fossil fuels and extend the energy flow from land to island.

  6. 大直径深层钻孔灌注桩拔除工艺研究%Research on Pulling-out Technology for Long Bored Pile with Large Diameter

    Institute of Scientific and Technical Information of China (English)

    裴迅; 芮大虎; 吴庆红; 葛执礼

    2015-01-01

    According to the characteristics of long and large diameter pile to be pulled out in the open-excavated tunnel ( pile-puling interval) in Zhengzhou, the force on pile body and the pile-pulling technology are studied.Through the analy-sis and calculation on failure mode of soil around the pile and tensile strength of the pile body in pulling-out process, the ef-fective method of resistance reduction is selected to be applied in the engineering practice, and good results are achieved. The solutions of pile body partial enlarged, too large pile lateral friction and pile broken in pile pulling-out operation are summed up, which can serve as reference for the same projects.%结合郑州南站连接线明挖隧道(拔桩区间)拟拔桩基直径大、桩长的特点,对桩体受力特征和拔桩工艺进行了研究。通过拔桩过程中桩周土破坏模式和桩体自身的抗拉强度分析计算,选取有效的减阻方法并应用于工程实践,取得良好效果。最后总结出大直径深层钻孔灌注桩拔除工程中桩身局部扩大、桩侧摩阻力过大和断桩等问题及相应的解决方法,供今后类似工程借鉴。

  7. Specialists' meeting on LMFBR fuel rod behaviour under operational transients, Kalpakkam, India, 3-6 December 1985

    International Nuclear Information System (INIS)

    IWGFR Specialists' Meeting on ''LMFBR Fuel Rod Behaviour Under Operational Transients'' was held in Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam during 3-6 December 1985. The meeting was attended by the representatives of Belgium, France, FRG, India, Italy, US, USSR, IAEA and observers from India. The purpose of the meeting was to provide a forum for the exchange of information on the subject of LMFBR Fuel Rod Behaviour Under Operational Transients. The meeting presentations were divided into sessions devoted to the following topics: Overview of National Programmes (3 papers); In-pile and out-pile experimental facilities and results (5 papers); Modelling and Code work (5 papers). A separate abstract was prepared for each of these papers

  8. PHC管桩接桩问题的检测%Detection of the PHC pipe pile joint of pile problems

    Institute of Scientific and Technical Information of China (English)

    陈军

    2009-01-01

    概括了低应变动测、高应变动测、静载荷试验及孔内摄像等方法检测PHC管桩时的优缺点,分析了管桩接桩问题产生的原因,进而提出了针对此问题的检测方案,从而避免因桩的接头问题引起的建筑物不均匀沉降.%The merits and drawbacks of low strain dynamic testing, dynamic high strain testing, dead load testing and down hole imaging todetect PHC pipe pile were generalized. The pipe pile joint of pile problems occurring reasons were analyzed, then the detected plan against to the problem was proposed, therefore avoided buildings uneven settlement provoked by pile joints problems.

  9. Global performance parameters for different pneumatic bioreactors operating with water and glycerol solution: experimental data and CFD simulation.

    Science.gov (United States)

    Rodriguez, G Y; Valverde-Ramírez, M; Mendes, C E; Béttega, R; Badino, A C

    2015-11-01

    Global variables play a key role in evaluation of the performance of pneumatic bioreactors and provide criteria to assist in system selection and design. The purpose of this work was to use experimental data and computational fluid dynamics (CFD) simulations to determine the global performance parameters gas holdup ([Formula: see text]) and volumetric oxygen transfer coefficient (k L a), and conduct an analysis of liquid circulation velocity, for three different geometries of pneumatic bioreactors: bubble column, concentric-tube airlift, and split tube airlift. All the systems had 5 L working volumes and two Newtonian fluids of different viscosities were used in the experiments: distilled water and 10 cP glycerol solution. Considering the high oxygen demand in certain types of aerobic fermentations, the assays were carried out at high flow rates. In the present study, the performances of three pneumatic bioreactors with different geometries and operating with two different Newtonian fluids were compared. A new CFD modeling procedure was implemented, and the simulation results were compared with the experimental data. The findings indicated that the concentric-tube airlift design was the best choice in terms of both gas holdup and volumetric oxygen transfer coefficient. The CFD results for gas holdup were consistent with the experimental data, and indicated that k L a was strongly influenced by bubble diameter and shape. PMID:26227509

  10. Global performance parameters for different pneumatic bioreactors operating with water and glycerol solution: experimental data and CFD simulation.

    Science.gov (United States)

    Rodriguez, G Y; Valverde-Ramírez, M; Mendes, C E; Béttega, R; Badino, A C

    2015-11-01

    Global variables play a key role in evaluation of the performance of pneumatic bioreactors and provide criteria to assist in system selection and design. The purpose of this work was to use experimental data and computational fluid dynamics (CFD) simulations to determine the global performance parameters gas holdup ([Formula: see text]) and volumetric oxygen transfer coefficient (k L a), and conduct an analysis of liquid circulation velocity, for three different geometries of pneumatic bioreactors: bubble column, concentric-tube airlift, and split tube airlift. All the systems had 5 L working volumes and two Newtonian fluids of different viscosities were used in the experiments: distilled water and 10 cP glycerol solution. Considering the high oxygen demand in certain types of aerobic fermentations, the assays were carried out at high flow rates. In the present study, the performances of three pneumatic bioreactors with different geometries and operating with two different Newtonian fluids were compared. A new CFD modeling procedure was implemented, and the simulation results were compared with the experimental data. The findings indicated that the concentric-tube airlift design was the best choice in terms of both gas holdup and volumetric oxygen transfer coefficient. The CFD results for gas holdup were consistent with the experimental data, and indicated that k L a was strongly influenced by bubble diameter and shape.

  11. Preliminary report on coal pile, coal pile runoff basins, and ash basins at the Savannah River Site: effects on groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, E. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1997-04-28

    Coal storage piles, their associated coal pile runoff basins and ash basins could potentially have adverse environmental impacts, especially on groundwater. This report presents and summarizes SRS groundwater and soil data that have been compiled. Also, a result of research conducted on the subject topics, discussions from noted experts in the field are cited. Recommendations are made for additional monitor wells to be installed and site assessments to be conducted.

  12. British Columbia's new coalbed methane royalty regime

    International Nuclear Information System (INIS)

    The British Columbia Ministry of Energy and Mines is promoting the development of the coalbed methane (CBM) industry in the province in order to make CBM a viable and competitive investment option for industry. It is establishing a regulatory and fiscal regime for CBM development. Issues of concern regarding CBM development include water production, gas production rates, well numbers, and marginal economics. The features of the CBM royalty regime include a new producer cost of service allowance, the creation of a CBM royalty tax bank to collect excess PCOS allowances, and a royalty tax credit for wells drilled by the end of February, 2004. The marginal well adjustment factor threshold has been raised from 180 mcf per day to 600 mcf per day for CBM only. It was noted that royalties will probably not be payable for several years following the first commercial well because royalties are very depending on capital and operating costs, local infrastructure and price. Royalty regimes cannot save CBM from low gas prices, poor resources or economics. 2 figs

  13. Experimental numerical study utilizing CFD in a stratified gasifier operating with biomass; Estudio numerico experimental de un gasificador estratificado que opera con biomasa, utilizando CFD

    Energy Technology Data Exchange (ETDEWEB)

    Rogel Ramirez, Alejandro

    2007-07-01

    The central idea behind this work is the developing of a numeric-experimental model, useful to optimize the biomass stratified gasifier design. Firstly, model validation will be carried up by comparison with reference experimental data available. This study describes a 1-D + 2-D numerical model used to simulate the gasification of pine wood pellets in a stratified downdraft gasifier whereby Eulerian conservation equations are solved for particle and gas phase components, velocities and specific enthalpies. The model takes into account the biomass particle process such as heating up, drying, primary pyrolysis of biomass, secondary pyrolysis of tar, homogeneous reactions and heterogeneous combustion/gasification reactions, and particle size change. This CFD model can be used to predict temperature profiles, gas composition, producer gas lower heating value, and carbon conversion efficiency, and the reactor performance when operating parameters and feed properties are changed. The standard {kappa}-{epsilon} and RNG {kappa}-{epsilon} models were used to simulate the turbulent flow conditions. [Spanish] La idea central del presente trabajo es el desarrollo de un modelo numerico- experimental, para optimizar el diseno de gasificadores estratificados de biomasa. Primeramente, el modelo sera validado utilizando datos experimentales disponibles en la literatura. Este estudio describe un modelo numerico 1-D+2-D, utilizado para simular la gasificacion de 'pelets' de madera de pino en un gasificador estratificado de flujos paralelos, en el que se resuelven ecuaciones de conservacion Eulerianas para los componentes de la fase gaseosa, la fase solida, velocidades y entalpias especificas. El modelo considera procesos como: calentamiento, secado de la biomasa, pirolisis primaria de la madera, pirolisis secundaria de los alquitranes, reacciones homogeneas, reacciones heterogeneas de combustion/gasificacion y cambio en el tamano de la particula. Este modelo CFD puede ser

  14. Retrenchment in British Universities: Lessons Learned.

    Science.gov (United States)

    Simpson, William A.

    1985-01-01

    A study of 14 British universities that underwent severe retrenchment in 1981-1984 is reported, and successful policies, procedures, philosophies, and techniques that may be applicable to institutions in many countries are outlined. (MSE)

  15. British Engineers and Africa 1875-1914

    DEFF Research Database (Denmark)

    Andersen, Casper

    the imperial diasporas, identities and networks that developed as the British engineering profession established connections on the African continent. Using a wide range of primary sources that include correspondence, diaries, technical reports, institutional minutes and periodicals, Andersen reconstructs...

  16. British Universities' Responses to Financial Reductions.

    Science.gov (United States)

    Sizer, John

    1987-01-01

    The impact on nine British universities' of substantial financial reductions in 1980-81 and the policy implications for national funding agencies are examined. Implementation of institutional retrenchment plans and the role of high-level administrators are discussed. (MSE)

  17. Experimental Evaluation of SI Engine Operation Supplemented by Hydrogen Rich Gas from a Compact Plasma Boosted Reformer

    International Nuclear Information System (INIS)

    It is well known that hydrogen addition to spark-ignited (SI) engines can reduce exhaust emissions and increase efficiency. Micro plasmatron fuel converters can be used for onboard generation of hydrogen-rich gas by partial oxidation of a wide range of fuels. These plasma-boosted microreformers are compact, rugged, and provide rapid response. With hydrogen supplement to the main fuel, SI engines can run very lean resulting in a large reduction in nitrogen oxides (NO x ) emissions relative to stoichiometric combustion without a catalytic converter. This paper presents experimental results from a microplasmatron fuel converter operating under variable oxygen to carbon ratios. Tests have also been carried out to evaluate the effect of the addition of a microplasmatron fuel converter generated gas in a 1995 2.3-L four-cylinder SI production engine. The tests were performed with and without hydrogen-rich gas produced by the plasma boosted fuel converter with gasoline. A one hundred fold reduction in NO x due to very lean operation was obtained under certain conditions. An advantage of onboard plasma-boosted generation of hydrogen-rich gas is that it is used only when required and can be readily turned on and off. Substantial NO x reduction should also be obtainable by heavy exhaust gas recirculation (EGR) facilitated by use of hydrogen-rich gas with stoichiometric operation

  18. Irish (Republic) versus British (North West) orthopaedic trainees: what are the differences?

    LENUS (Irish Health Repository)

    Banks, L N

    2012-02-01

    British Trainees have gradually had their working week curtained over the last 8 years. The Republic of Ireland Trainees have not been subjected to the European Working Time Directive prior to 2009 and have therefore worked on average, more hours than their British counterparts. We wanted to see if the differing schemes had an impact on recruiting and training orthopaedic surgeons. We surveyed Republic of Ireland orthopaedic specialist registrars (SpRs) and North West (NW) British SpRs\\/specialist trainees (ST3 and above) to see if there were any discernable differences in working patterns and subsequent training exposure. A standard proforma was given to Irish Trainees and to NW SpRs\\/STs at their National or regional teaching (January\\/February 2009). 62% of Irish and 47% of British NW Trainees responded. Irish trainees were more likely to have obtained a post-graduate degree (p = 0.03). The Irish worked more hours per week (p < 0.001) doing more trauma operative lists (p = 0.003) and more total cases per 6 months than the NW British (p = 0.003). This study suggests that more hours worked, equals more operative exposure, without detriment to the academic side of training. Obviously it is not possible to say whether fewer operations make for a poorer surgeon, but the evidence suggests that it may be true.

  19. Seismic response of tall building considering soil-pile-structure interaction

    Science.gov (United States)

    Han, Yingcai

    2002-06-01

    The seismic behavior of tall buildings can be greatly affected by non-linear soil-pile interaction during strong earthquakes. In this study a 20-storey building is examined as a typical structure supported on a pile foundation for different conditions: (1) rigid base, i.e. no deformation in the foundation: (2) linear soil-pile system; and (3) nonlinear soil-pile system. The effects of pile foundation displacements on the behavior of tall building are investigated, and compared with the behavior of buildings supported on shallow foundation. With a model of non-reflective boundary between the near field and far field, Novak’s method of soil-pile interaction is improved. The computation method for vibration of pile foundations and DYNAN computer program are introduced comprehensively. A series of dynamic experiments have been done on full-scale piles, including single pile and group, linear vibration and nonlinear vibration, to verify the validity of boundary zone model.

  20. Numerical Analysis of the Stability of Embankment Slope Reinforced with Piles

    Institute of Scientific and Technical Information of China (English)

    CUI Wei; ZHANG Zhigeng; YAN Shuwang

    2007-01-01

    The effects of stabilizing piles on the stability of an embankment slope are analyzed by numerical simulation. The shear strength reduction method is used for the analysis, and the soil - pile interaction is simulated with zero-thickness elasto-plastic interface elements. Effects of pile spacing and pile position on the safety factor of slope and the behavior of piles under these conditions are given. The numerical analysis indicates that the positions of the pile have significant influence on the stability of the slope, and the pile needs to be installed in the middle of the slope for maximum safety factors. In the end, the soil arching effect closely associated with the space between stabilizing piles is analyzed. The results are helpful for design and construction of stabilizing piles.