WorldWideScience

Sample records for bearing piles

  1. Evaluation of axial pile bearing capacity based on pile driving analyzer (PDA) test using Neural Network

    Science.gov (United States)

    Maizir, H.; Suryanita, R.

    2018-01-01

    A few decades, many methods have been developed to predict and evaluate the bearing capacity of driven piles. The problem of the predicting and assessing the bearing capacity of the pile is very complicated and not yet established, different soil testing and evaluation produce a widely different solution. However, the most important thing is to determine methods used to predict and evaluate the bearing capacity of the pile to the required degree of accuracy and consistency value. Accurate prediction and evaluation of axial bearing capacity depend on some variables, such as the type of soil, diameter, and length of pile, etc. The aims of the study of Artificial Neural Networks (ANNs) are utilized to obtain more accurate and consistent axial bearing capacity of a driven pile. ANNs can be described as mapping an input to the target output data. The method using the ANN model developed to predict and evaluate the axial bearing capacity of the pile based on the pile driving analyzer (PDA) test data for more than 200 selected data. The results of the predictions obtained by the ANN model and the PDA test were then compared. This research as the neural network models give a right prediction and evaluation of the axial bearing capacity of piles using neural networks.

  2. 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...

  3. 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.

  4. Contribution to Estimating Bearing Capacity of Pile in Clayey Soils

    Directory of Open Access Journals (Sweden)

    Drusa Marián

    2016-12-01

    Full Text Available The estimation of real geotechnical parameters is key factor for safe and economic design of geotechnical structures. One of these are pile foundations, which require proper design and evaluation due to accessing more deep foundation soil and because remediation work of not bearable piles or broken piles is a crucial operation. For this reason, geotechnical field testing like cone penetration test (CPT, standard penetration (SPT or dynamic penetration test (DP are realized in order to receive continuous information about soil strata. Comparing with rotary core drilling type of survey with sampling, these methods are more progressive. From engineering geologist point of view, it is more important to know geological characterization of locality but geotechnical engineers have more interest above the real geotechnical parameters of foundation soils. The role of engineering geologist cannot be underestimated because important geological processes in origin or during history can explain behaviour of a geological environment. In effort to streamline the survey, investigation by penetration tests is done as it is able to provide enough information for designers. This paper deals with actual trends in pile foundation design; because there are no new standards and usable standards are very old. Estimation of the bearing capacity of a single pile can be demonstrated on the example of determination of the cone factor Nk from CPT testing. Then results were compared with other common methods.

  5. The effect of loading rate on pile bearing capacity of saturated sand

    NARCIS (Netherlands)

    Archeewa, E.

    2005-01-01

    Pile load tests are commonly used by engineers to determine its bearing capacity. At present, there are three methods of pile load tests: the static, the dynamic and the quasi-static test. The static pile load test is done by applying an axial load on the pile with a long duration. The dynamic and

  6. Optimization of bearing capacity and unsymmetrical settlement of vertical pile group using genetic algorithm

    Directory of Open Access Journals (Sweden)

    Saeed Ghaffarpour Jahromi

    2016-06-01

    Full Text Available Capacity of pile group is the summation of the individual piles capacity with influence of spacing between the piles. Pile groups usually have the same length, so if the spacing between piles is too close, the zones of stress around the pile will overlap and the ultimate load of the group is less than the sum of the individual pile capacities especially in the case of friction piles, where the efficiency of pile group is much less. In this research the optimization of bearing capacity and unsymmetrical settlement of cap in the vertical pile group using genetic algorithm were studied. Friction pile in granular soil, with different length and arrangement were investigated to find the best performance of the group for the axial stiffness, bearing capacity and unsymmetrical settlement. The criterion of optimization is the volume of concrete needs for piles and cap. Two patterns of 5×5 pile groups (row variation and squared variation are studied in this research. The analysis of pile group to find bearing capacity was conducted using the finite element software (Fb-pier and for optimization used evolutionary genetic algorithm method.

  7. A Vertical Bearing Capacity Experimental Analysis of Prestressed Concrete Piles Based on Material Constitutive Relation of Piles and Soil

    Directory of Open Access Journals (Sweden)

    Yi Fan

    2016-01-01

    Full Text Available The purpose of the paper is to research the vertical bearing capacity and settlement idiosyncracies of prestressed concrete piles. In-situ experiments, which was carried out by anchor-pile beam counterforce device, and numerical analysis methods was adopted as research methods on 3 tested piles. Mohr-Coulomb model was employed as the constitutive model of soil mass and isotropic elastic damage model as the constitutive model of piles to analyze its yield functions. Furthermore, the basic idea of modelling large deformation problems was analyzed based on Finite Difference Method (FDM. The comparison results was obtained in the paper and it suggested that the simulated data is highly identical with the experimental ones. Load-settlement curve basically presents a quadratic function form.

  8. 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.

  9. Seismic Bearing Capacity of Strip Footings on Pile-Stabilized Slopes

    Directory of Open Access Journals (Sweden)

    Maryam Haghbin

    2016-06-01

    Full Text Available This paper develops an analytical method to calculate seismic bearing capacity of a strip footing, which is located on a slope reinforced with rows of pile. The resistance of passive pile is determined based on normal and shear stress of the soil around the pile, which is then compared to other analytical methods. This comparison indicates an acceptable agreement. The variants of the study include location of pile rows, location of footing with respect to the slope crest, foundation depth, and horizontal seismic coefficient. The footing seismic bearing capacity is calculated based on seismic slope stability with limit analysis method (yield acceleration coefficient of reinforced slope with pile row as well as soil stability beneath the footing by means of virtual retaining wall method. The main objective is to determine and establish the relation between various parameters and seismic bearing capacities of the footing, and to find the best location of the pile row that gives the best improvement in the footing seismic bearing capacity. Results indicate that stabilizing the earth slope with rows of piles has a significant effect on the improvement of seismic bearing capacity of the footing. In addition, the results of the present method are compared with those, reported by others, to demonstrate a reasonable agreement.

  10. The Ultimate Pile Bearing Capacity from Conventional and Spectral Analysis of Surface Wave (SASW) Measurements

    Science.gov (United States)

    Faizah Bawadi, Nor; Anuar, Shamilah; Rahim, Mustaqqim A.; Mansor, A. Faizal

    2018-03-01

    A conventional and seismic method for determining the ultimate pile bearing capacity was proposed and compared. The Spectral Analysis of Surface Wave (SASW) method is one of the non-destructive seismic techniques that do not require drilling and sampling of soils, was used in the determination of shear wave velocity (Vs) and damping (D) profile of soil. The soil strength was found to be directly proportional to the Vs and its value has been successfully applied to obtain shallow bearing capacity empirically. A method is proposed in this study to determine the pile bearing capacity using Vs and D measurements for the design of pile and also as an alternative method to verify the bearing capacity from the other conventional methods of evaluation. The objectives of this study are to determine Vs and D profile through frequency response data from SASW measurements and to compare pile bearing capacities obtained from the method carried out and conventional methods. All SASW test arrays were conducted near the borehole and location of conventional pile load tests. In obtaining skin and end bearing pile resistance, the Hardin and Drnevich equation has been used with reference strains obtained from the method proposed by Abbiss. Back analysis results of pile bearing capacities from SASW were found to be 18981 kN and 4947 kN compared to 18014 kN and 4633 kN of IPLT with differences of 5% and 6% for Damansara and Kuala Lumpur test sites, respectively. The results of this study indicate that the seismic method proposed in this study has the potential to be used in estimating the pile bearing capacity.

  11. Bearing capacity of helical pile foundation in peat soil from different, diameter and spacing of helical plates

    Science.gov (United States)

    Fatnanta, F.; Satibi, S.; Muhardi

    2018-03-01

    In an area dominated by thick peat soil layers, driven piles foundation is often used. These piles are generally skin friction piles where the pile tips do not reach hard stratum. Since the bearing capacity of the piles rely on the resistance of their smooth skin, the bearing capacity of the piles are generally low. One way to increase the bearing capacity of the piles is by installing helical plates around the pile tips. Many research has been performed on helical pile foundation. However, literature on the use of helical pile foundation on peat soil is still hardly found. This research focus on the study of axial bearing capacity of helical pile foundation in peat soil, especially in Riau Province. These full-scale tests on helical pile foundation were performed in a rectangular box partially embedded into the ground. The box is filled with peat soil, which was taken from Rimbo Panjang area in the district of Kampar, Riau Province. Several helical piles with different number, diameter and spacing of the helical plates have been tested and analysed. The tests result show that helical pile with three helical plates of uniform diameter has better bearing capacity compared to other helical piles with varying diameter and different number of helical plates. The bearing capacity of helical pile foundation is affected by the spacing between helical plates. It is found that the effective helical plates spacing for helical pile foundation with diameter of 15cm to 35cm is between 20cm to 30cm. This behaviour may be considered to apply to other type of helical pile foundations in peat soil.

  12. Study on load-bearing characteristics of a new pile group foundation for an offshore wind turbine.

    Science.gov (United States)

    Lang, Ruiqing; Liu, Run; Lian, Jijian; Ding, Hongyan

    2014-01-01

    Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect.

  13. Study on Load-Bearing Characteristics of a New Pile Group Foundation for an Offshore Wind Turbine

    Science.gov (United States)

    Liu, Run; Lian, Jijian; Ding, Hongyan

    2014-01-01

    Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect. PMID:25250375

  14. Improving the bearing capacity of footing on soft clay with sand pile with/without skirts

    OpenAIRE

    Nazir, Ashraf Kamal; Azzam, Wasim R.

    2010-01-01

    This paper presents the results of laboratory model tests for studying the improvement of soft clay layer by using both partially replaced sand piles with/without confinement. This research is performed to study the effect of sand pile to improve the bearing capacity and to control the settlement. Also the research aimed at investigating the variation of subgrade modulus, and the induced failure mechanism of shallow circular footing on replaced soil with/without skirts. The results show that ...

  15. Improving the bearing capacity of footing on soft clay with sand pile with/without skirts

    Directory of Open Access Journals (Sweden)

    Ashraf Kamal Nazir

    2010-12-01

    Full Text Available This paper presents the results of laboratory model tests for studying the improvement of soft clay layer by using both partially replaced sand piles with/without confinement. This research is performed to study the effect of sand pile to improve the bearing capacity and to control the settlement. Also the research aimed at investigating the variation of subgrade modulus, and the induced failure mechanism of shallow circular footing on replaced soil with/without skirts. The results show that the improvement of load bearing capacity is remarkable; using both partially replaced sand pile with and without confinement by skirts. The adopted technique can substantially modify the stress displacement curve of the footing rested on soft clay layer, significantly decreases the settlement and the replaced soil block inside the skirts behave as deep foundation. Therefore, the bearing capacity failure mechanism of a footing rested on soft clay can be modified from exclusive settlement to general bearing capacity failure at the tip of confined replaced sand column.

  16. Analysis of Bearing Capacity Pile Foundation with Using Capwap Software for Testing Pile Driving Analyzer (pda) at Fasfel Development Project Parlimbungan Ketek Sikara-Kara Mandailing Natal District (north Sumatera)

    Science.gov (United States)

    Oberlyn Simanjuntak, Johan; Suita, Diana

    2017-12-01

    Pile foundation is one type deep foundation that serves to distribute the load of hard soil structure loading which has a high bearing capacity that is located deep enough inside the soil. To determine the bearing capacity of the pile and at the same time control the Calendring results, the Pile Driving Analyzer (PDA) test at 8 pile sections from the 84 point piling section (10% of the number sections), the results were analyzed by CAPWAP SOFTWARE, and the highest bearing capacity of Ru 177 ton and the lowest bearing capacity of 111 tons, is bigger than the plan load which load plans that is 60,9 tons. Finally the PDA safe is bearing bearing capacity of the load planning.

  17. The Use of Tactile Sensors and PIV Analysis for Understanding the Bearing Mechanism of Pile Groups.

    Science.gov (United States)

    You, Zhijia; Chen, Yulong

    2018-02-06

    Model tests were carried out in dry silica sand under pile loading and visualizing observation to investigate the behavior of a pile group. The pile group consisted of nine cylindrical model piles of 40 mm in diameter in most tests or three rectangular parallelepiped model piles in the visualizing observation. Pile spacings of 200 mm and 100 mm between pile centers were used in the models. Tactile sensors were installed to measure the pressure distribution in the ground and colored sand layer with particle image velocimetry (PIV) analysis to reveal the ground deformation in addition to strain gauges inside the model piles to investigate the interaction among group piles. The tests results showed that a narrower spacing between piles resulted in a wider affected area of the ground and the interaction was more significant below the tips.

  18. Model Test Research on the End Bearing Behavior of the Large-Diameter Cast-in-Place Concrete Pile for Jointed Rock Mass

    Directory of Open Access Journals (Sweden)

    Jingwei Cai

    2016-01-01

    Full Text Available For large-diameter, cast-in-place concrete piles, the end bearing capacity of a single pile is affected by discontinuous surfaces that exist in natural rock masses when the bearing layer of the pile end is located in the rock layer. In order to study the influence of the jointed dip angle on the bearing characteristics of the pile end, the discrete element models are adopted to simulate the mechanical characteristics of the jointed rock masses, and the model tests of the failure mode of the jointed rock masses were also designed. The results of the numerical calculations and modeling tests show that the joints, which have a filtering effect on the internal stress of the bedrock located at the pile end, change the load transferring paths. And the failure mode of the jointed rock foundation also changes as jointed dip angle changes. The rock located at the pile end generally presents a wedge failure mode. In addition, the Q-S curves obtained by model tests show that the ultimate end bearing capacity of a single pile is influenced by the jointed dip angle. The above results provide an important theoretical basis for how to correctly calculate end resistance for a cast-in-place concrete pile.

  19. Axial compressive bearing capacity of piles in oil-contaminated sandy soil using FCV

    NARCIS (Netherlands)

    Mohammadi, Amirhossein; Ebadi, Taghi; Eslami, Abolfazl; Zee, van der S.E.A.T.M.

    2018-01-01

    Oil and its derivatives contaminate many soils and not only affect their chemical and biological properties but also their geotechnical properties. As oil contamination may deteriorate the functioning of piles, this paper addresses the effects of oil contamination on soil–pile interactions. Axial

  20. Evaluation of bearing capacity of piles from cone penetration test data.

    Science.gov (United States)

    1999-11-01

    This study presents an evaluation of the performance of eight cone penetration test (CPT) methods in predicting the ultimate load carrying capacity of square precast prestressed concrete (PPC) piles driven into Louisiana soils. A search in the DOTD f...

  1. Investigating of Factors Affecting the Bearing Capacity and Settlement of the Composite Pile Group under Vertical Load

    Directory of Open Access Journals (Sweden)

    Saeed Ghaffarpour Jahromi

    2015-12-01

    Full Text Available The goal of this research is to study the effect of the space between long and short piles beneath combined deep foundation caps on the forces acting on piles and the resulting summit, all done by considering variables such as; short pile length, soil pad stiffness (cushion, short pile stiffness and long pile stiffness, using a modeling and numerical analysis method. Modeling and numerical analysis are performed using the Abacus software, which results indicated that by increasing the space between short and long piles, the compressive axial tension acting on short piles rises and the compressive axial tension acting on long piles almost reduces, and also increasing the space between short and long piles will reduce the resulting summit and by rising the elastic modulus of short piles the summit reduces and increasing the elastic modulus of long and short piles results in reducing the summit.

  2. Influence of Installation Effects on Pile Bearing Capacity in Cohesive Soils – Large Deformation Analysis Via Finite Element Method

    Directory of Open Access Journals (Sweden)

    Konkol Jakub

    2017-03-01

    Full Text Available In this paper, the whole process of pile construction and performance during loading is modelled via large deformation finite element methods such as Coupled Eulerian Lagrangian (CEL and Updated Lagrangian (UL. Numerical study consists of installation process, consolidation phase and following pile static load test (SLT. The Poznań site is chosen as the reference location for the numerical analysis, where series of pile SLTs have been performed in highly overconsolidated clay (OCR ≈ 12. The results of numerical analysis are compared with corresponding field tests and with so-called “wish-in-place” numerical model of pile, where no installation effects are taken into account. The advantages of using large deformation numerical analysis are presented and its application to the pile designing is shown.

  3. Finite element analysis of gravel pile composite foundation under flexible foundation of Airport Engineering

    Science.gov (United States)

    Luo, Min

    2018-02-01

    On the basis of consulting data, the bearing mechanism of gravel pile composite foundation is analyzed in this paper. The use of ANSYS software under flexible foundation according to the plum blossoms gravel pile additional stress between pile and soil additional stress distribution, load on pile top stress and pile bearing rate of modulus ratio between pile and soil on the pile top stress and rate of pile bearing capacity, pile-soil effect the stress ratio was calculated and analyzed, providing reasonable design reference for the design of gravel pile composite foundation.

  4. Introduction of effective piles in a base structure

    Directory of Open Access Journals (Sweden)

    В.Б. Кашка

    2005-03-01

    Full Text Available  Design features of effective piles such as СВ and their advantages in use are considered at the device of the pile bases in comparison with widely widespread types of piles. From results of comparative tests of piles under static pressing loading in different earth conditions the tendency of redistribution of bearing (carrying ability between a trunk and expansions an effective pile such as СВ was determined on earth conditions.

  5. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 1 - mechanical properties of FRP piles.

    Science.gov (United States)

    2014-10-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 1, Mechanical Properties of FRP Piles. : Mechanical and geotechnic...

  6. 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...... design methods. The methods proposed by Fleming et al. and Reese & O’Neill seem to produce the best match with the test results....

  7. Some Remarks on Foundation Pile Testing Procedures

    Science.gov (United States)

    Rybak, Jarosław

    2017-10-01

    This work presents the review of pile capacity testing techniques. In an overview, the key points in pile designing are: determination of the appropriate computational schemes, reliable data on loads and the properties of structural materials (in particular, of the soil mass, which is marked by the greatest variability). The procedure of constructing a pile foundation should include: carrying out soil tests in the scope that ensures safe designing, selecting a piling technology that is relevant both to geotechnical conditions and expected loads, drafting a piling design together with the design of load tests, setting up a testing station for further load tests, static and/or dynamic tests of pile load capacity, preceded by supplementary soil tests when the conditions of test pile installation fail to comply with the design assumptions or when the pile length exceeds the depth of the previously investigated soil, making documentation of load capacity tests (with an additional correction of the piling design), the actual piling (ongoing analysis of pile driving logs and, if necessary, testing the piles’ integrity), drawing up the as-built documentation. Unfortunately, the design is corrected after the load test have been conducted only if the piles fail to show the designed bearing capacity. The designer is then obliged to revise the design assumptions on the basis of tests results. If the test results account for the a greater bearing capacity than necessary and it would be recommendable to limit the extent of the planned (i.e. set out in the contract) piling works, usually neither the contractor nor the designer, nor even the Construction Site Supervisor, acting for the benefit of the Investor, are willing to take on the responsibility for reducing the scope of the piling works. The necessity of conducting additional control tests before and during the implementation of the construction project is often treated by the investors as an attempt at extorting extra

  8. Thermomechanical Behavior of Energy Pile Embedded in Sandy Soil

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    Xu Huang

    2018-01-01

    Full Text Available The traditional energy pile (solid energy pile has been implemented for decades. However, the design of different kinds of energy piles is still not well understood. In this study, a series of model tests were performed on an aluminum pipe energy pile (PEP in dry sandy soil to investigate the thermal effects on the mechanical behaviors of pipe energy pile. The thermal responses of the PEP were also analyzed. Steady temperatures of the PEP under different working conditions were also compared with that of the solid energy pile. Different loading tests were carried out on four pipe energy piles under three different temperatures of 5, 35, and 50°C, respectively. The bearing capacity change can be interpreted through the load-displacement curves. Experiment results were also compared with the solid energy pile to evaluate bearing capacities of the PEP and the solid energy pile under different temperature conditions. The mobilized shaft resistance was also calculated and compared with the solid energy pile data and the results show that the PEP has a similar load transfer mechanism with the solid energy pile. It could also be found that, for PEPs under working load, plastic displacement would appear after a whole heating cycle.

  9. 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...

  10. The pile EL3; Pile EL3

    Energy Technology Data Exchange (ETDEWEB)

    Robert, J.; Raievski, V. [Commissariat a l' Energie Atomique, Paris (France). Centre d' Etudes Nucleaires; Hainzelin, J. [Chantiers de l' Atlantique (Penhoet-Loire), 75 - Paris (France)

    1959-07-01

    The programme of the high flux laboratory pile EL3 was laid down in october 1954. It is a heavy-water moderated and cooled pile. The fuel rods are of uranium metal with 1.6 per cent - 2 per cent of molybdenum, with aluminium canning. The maximum thermal flux in the moderator is 10{sup 14} n/cm{sup 2}/s. Studies began in january 1955, construction in may 1955, and the first divergence took place in July 1957. This report gives a general description of the pile and its adjacent buildings, the physical study of the pile, and certain technological studies carried out for the construction of EL3. (author) [French] Le programme de la pile laboratoire a haut flux EL3, a ete fixe en octobre 1954. C'est une pile moderee et refroidie a l'eau lourde. Les barres de combustible sont en uranium metal a 1,6 pour cent - 2 pour cent de molybdene, gainees a l'aluminium. Le flux thermique maximum dans le moderateur est de 10{sup 14} n/cm{sup 2}/s. Les etudes ont commence en janvier 1955, la construction en mai 1955, la premiere divergence a eu lieu en juillet 1957. On trouvera dans ce rapport, une description generale de la pile et de ses batiments annexes, l'etude physique de la pile et un certain nombre d'etudes technologiques executees pour la construction d'EL3. (auteur)

  11. Integrity and As-built capacity of bored pile group

    International Nuclear Information System (INIS)

    Shaw, D.E.; Kissenpfennig, J.F.; Huemmer, M.R.

    1983-01-01

    This paper discusses the application of statistical methods to the reliability evaluation of cast-in-place concrete piles. The difficulties associated with pile construction can lead to larger uncertainties than would be associated with normal reinforced concrete structures both due to uncertainty in concrete quality and end bearing capacity. These uncertainties can be dealt with through the use of statistical methods. A statistical model of an individual pile is formulated along with a methodology for determining necessary statistical parameters from results of concrete batch tests, core strength tests and visual logs, sonic geophysical testing methods, and proof tests. Strength models for both static vertical and seismic horizontal loadings are discussed. The overall safety of a pile foundation is dependent upon the distribution of individual pile strength as well as the additional reliability due to the use of a large number of parallel load paths provided by a pile group foundation. The paper presents a mechanical model of global pile behavior which accounts for individual pile ductility along with the possibility of redistribution of loads from weaker to stronger piles. The use of the Monte Carlo method to determine the overall reliability of the pile foundation is discussed. Numerical results for both individual pile behavior as well as overall foundation behavior are presented. (orig.)

  12. Precipitation of uraninite in chlorite-bearing veins of the hydrothermal alteration zone (argile de pile) of the natural nuclear reactor at Bangombe, Republic of Gabon

    International Nuclear Information System (INIS)

    Eberly, P.; Ewing, R.; Janeczek, J.

    1995-01-01

    This paper describes the mineralogy of a phyllosilicate/uraninite/galena-bearing vein located within the hydrothermal alteration halo associated with the Bangombe reactor. Phyllosilicates within the vein include a trioctahedral Al-Mg-Fe chlorite (ripidolite), Al-rich clay (kaolinite and/or donbassite) and illite. Textural relations obtained by backscattered-electron imaging suggest that ripidolite crystallized first among the sheet silicates. Uraninite is spatially associated with ripidolite and probably precipitated at a later time. While energy-dispersive X-ray analyses suggest that the uranium phase is predominantly uraninite, coffinite or other phases may also be present

  13. Experimental Verification of Integrity of Low-Pressure Injection Piles Structure - Pile Internal Capacity

    Science.gov (United States)

    Pachla, Henryk

    2017-12-01

    The idea of strengthening the foundation using injection piles lies in transferring loads from the foundation to the piles anchorage in existing structure and formed in the soil. Such a system has to be able to transfer loads from the foundation to the pile and from the pile onto the soil. Pile structure often reinforced with steel element has to also be able to transfer such a loading. According to the rules of continuum mechanics, the bearing capacity of such a system and a deformation of its individual elements can be determined by way of an analysis of the contact problem of three interfaces. Each of these surfaces is determined by different couples of materials. Those surfaces create: pile-foundation anchorage, bonding between reinforcement and material from which the pile is formed and pilesoil interface. What is essential is that on the contact surfaces the deformation of materials which adhere to each other can vary and depends on the mechanical properties and geometry of these surfaces. Engineering practice and experimental research point out that the failure in such structures occurs at interfaces. The paper is concentrating on presenting the experiments on interaction between cement grout and various types of steel reinforcement. The tests were conducted on the special low pressure injection piles widely used to strengthen foundations of already existing structures of historical buildings due to the technology of formation and injection pressure.

  14. Experimental Verification of Integrity of Low-Pressure Injection Piles Structure – Pile Internal Capacity

    Directory of Open Access Journals (Sweden)

    Pachla Henryk

    2017-12-01

    Full Text Available The idea of strengthening the foundation using injection piles lies in transferring loads from the foundation to the piles anchorage in existing structure and formed in the soil. Such a system has to be able to transfer loads from the foundation to the pile and from the pile onto the soil. Pile structure often reinforced with steel element has to also be able to transfer such a loading. According to the rules of continuum mechanics, the bearing capacity of such a system and a deformation of its individual elements can be determined by way of an analysis of the contact problem of three interfaces. Each of these surfaces is determined by different couples of materials. Those surfaces create: pile-foundation anchorage, bonding between reinforcement and material from which the pile is formed and pilesoil interface. What is essential is that on the contact surfaces the deformation of materials which adhere to each other can vary and depends on the mechanical properties and geometry of these surfaces. Engineering practice and experimental research point out that the failure in such structures occurs at interfaces. The paper is concentrating on presenting the experiments on interaction between cement grout and various types of steel reinforcement. The tests were conducted on the special low pressure injection piles widely used to strengthen foundations of already existing structures of historical buildings due to the technology of formation and injection pressure.

  15. 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

  16. 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.

  17. The pile EL3

    International Nuclear Information System (INIS)

    Robert, J.; Raievski, V.

    1959-01-01

    The programme of the high flux laboratory pile EL3 was laid down in october 1954. It is a heavy-water moderated and cooled pile. The fuel rods are of uranium metal with 1.6 per cent - 2 per cent of molybdenum, with aluminium canning. The maximum thermal flux in the moderator is 10 14 n/cm 2 /s. Studies began in january 1955, construction in may 1955, and the first divergence took place in July 1957. This report gives a general description of the pile and its adjacent buildings, the physical study of the pile, and certain technological studies carried out for the construction of EL3. (author) [fr

  18. Mechanical and deformation analyses of pile foundation for supporting structure of off-shore wind turbine at Changhua coast in Taiwan

    Science.gov (United States)

    Wang, W. C.; Lin, D. G.

    2015-12-01

    This study investigates the bearing capacities and mechanical behaviors of pile foundation installed on the seabed of wind farm near Chang-Hua coast of western Taiwan for the supporting structure of offshore wind turbine. A series of three-dimensional (3-D) numerical modeling of pile foundation subjected to various types of combined loading were carried out using Plaix-3D finite element program to investigate the interactive behaviors between soil and pile. In the numerical modeling, pile diameter, pile length and pile spacing were selected as design parameters to inspect their effects on the bearing capacities and deformation behaviors of the pile foundation. For a specific design parameter combination, one can obtain the corresponding loading-displacement curve, various ultimate bearing capacities, V-H (Vertical-Horizontal combined loading) ultimate bearing capacity envelope, and p-ycurve of pile foundation. Numerical results indicate that: (1) Large displacement and plastic points at ultimate state mostly distribute and concentrate in the topsoil of seabed and around pile head. (2) The soil resistance on the soil-pile interface is ascending with the increases of depth, pile diameter and pile length. (3) The vertical and horizontal bearing capacities of pile group increase significantly with the increase of pile diameter. (4) The vertical and bending moment capacities of pile group increase greatly with the increase of pile length whereas the horizontal capacity is almost insensitive to pile length. (5) The bending moment of pile is highly influenced by the pile spacing. (6) For different design parameters, the shape of ultimate bearing capacity envelopes of pile group on V-H plane is similar while the envelopes will expand as the design parameters increase. For different loading levels of bending moment, the envelopes on V-H plane will contract gradually as the bending moment loading increasing.

  19. PROCESS DIAGRAMS FOR INSTALLATION OF DRIVEN PILES IN PENETRATED WELLS

    Directory of Open Access Journals (Sweden)

    Kovalev Vladimir Aleksandrovich

    2017-03-01

    Full Text Available This article presents the main options of improved and newly devised designs and process diagrams for installation of foundations made of driven, or jack, piles in the penetrated wells with expanded shoe, mainly in weak wet (waterlogged and water-saturated soils. The article presents six options of process diagrams for installation of driven piles in penetrated wells, listing the main procedures: for well-compacted weak soils, for the case when the water ingress is excluded, for the case when it is necessary to increase the load-bearing capacity of pile's bearing face in the waterlogged soils, for the case when the load-bearing capacity of the pile shall be increased both for the end and for the sides, for the case when peat or other biogenous water-saturated soils are present at the bottom of the well, and for the case when there is no contracted zone nor practical possibility to ensure the stability of the walls. The proposed six options of process diagrams for installation of the driven piles in penetrated wells provide expansion of their area of application regarding the soil conditions, increase of load-bearing capacity, and possibility of using jack systems for driving the piles under conditions of dense urban development.

  20. Pile foundation of nuclear power plant structures

    International Nuclear Information System (INIS)

    Jurkiewicz, W.J.; Thomaz, E.; Rideg, P.; Girao, M.

    1978-01-01

    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)

  1. An experimental study on mechanical properties of fiber-reinforced concrete of energy piles

    Directory of Open Access Journals (Sweden)

    Songying Zhao

    2017-07-01

    Full Text Available The technology of energy piles for heat storage involves turning the concrete piles buried beneath the ground into a part of the ground-source heat pump system and burying the heat-transfer tubes in the foundation piles, which are regarded as heat transfer wells. The heat transfer tubes are embedded in the concrete foundation piles, destroying the mechanical bearing capacity of the piles and damaging the safety of the buildings. Thus, considering the structural stability and the degree of heat transfer of concrete piles, as well as the selection of material for the foundation piles, the mixing ratio of the material of the energy piles is experimentally studied by the orthogonal method. The optimum mixing ratio of the energy pile is thus obtained. A concrete test block is used to conduct a static load test and splitting test to verify the mixing ratio of the concrete of the energy pile. The results show that steel fiber can be used to enhance the bearing capacity of the storage pile as a reinforcement material. Under a reasonable ratio, the reinforced pile can absolutely meet the original design requirements. Ordinary Portland cement or composite Portland cement can be used as cementitious materials for energy piles. Through an experiment, it is proved that the composite Portland cement can better meet the requirements of the concrete foundation piles than the cementitious material. As thermal conductivity materials, the addition of industrial graphite and scrap copper slag can improve the thermal conductivity of the pile, but it can also reduce the mechanical properties of the pile. It is necessary to control it in a certain range and not to add a large amount of graphite just to improve the thermal conductivity.

  2. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 6 - FRP composite pile axial compression testing.

    Science.gov (United States)

    2015-04-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 6, FRP Composite Pile Axial Compression : Testing. : Hollow and conc...

  3. Seismic Dynamic Damage Characteristics of Vertical and Batter Pile-supported Wharf Structure Systems

    Directory of Open Access Journals (Sweden)

    Li Jiren

    2015-10-01

    Full Text Available Considering a typical steel pipe pile-supported wharf as the research object, finite element analytical models of batter and vertical pile structures were established under the same construction site, service, and geological conditions to investigate the seismic dynamic damage characteristics of vertical and batter pile-supported wharf structures. By the numerical simulation and the nonlinear time history response analysis of structure system and the moment–axial force relation curve, we analyzed the dynamic damage characteristics of the two different structures of batter and vertical piles under different seismic ground motions to provide reasonable basis and reference for designing and selecting a pile-supported wharf structure. Results showed that the axial force of batter piles was dominant in the batter pile structure and that batter piles could effectively bear and share seismic load. Under the seismic ground motion with peak ground acceleration (PGA of 350 Gal and in consideration of the factors of the design requirement of horizontal displacement, the seismic performance of the batter pile structure was better than that of the vertical pile structure. Under the seismic ground motion with a PGA of 1000 Gal, plastic failure occurred in two different structures. The contrastive analysis of the development of plastic damage and the absorption and dissipation for seismic energy indicated that the seismic performance of the vertical pile structure was better than that of the batter pile structure.

  4. Stress transfer from pile group in saturated and unsaturated soil using theoretical and experimental approaches

    Directory of Open Access Journals (Sweden)

    al-Omari Raid R.

    2017-01-01

    Full Text Available Piles are often used in groups, and the behavior of pile groups under the applied loads is generally different from that of single pile due to the interaction of neighboring piles, therefore, one of the main objectives of this paper is to investigate the influence of pile group (bearing capacity, load transfer sharing for pile shaft and tip in comparison to that of single piles. Determination of the influence of load transfer from the pile group to the surrounding soil and the mechanism of this transfer with increasing the load increment on the tip and pile shaft for the soil in saturated and unsaturated state (when there is a negative pore water pressure. Different basic properties are used that is (S = 90%, γd = 15 kN / m3, S = 90%, γd = 17 kN / m3 and S = 60%, γd =15 kN / m3. Seven model piles were tested, these was: single pile (compression and pull out test, 2×1, 3×1, 2×2, 3×2 and 3×3 group. The stress was measured with 5 cm diameter soil pressure transducer positioned at a depth of 5 cm below the pile tip for all pile groups. The measured stresses below the pile tip using a soil pressure transducer positioned at a depth of 0.25L (where L is the pile length below the pile tip are compared with those calculated using theoretical and conventional approaches. These methods are: the conventional 2V:1H method and the method used the theory of elasticity. The results showed that the method of measuring the soil stresses with soil pressure transducer adopted in this study, gives in general, good results of stress transfer compared with the results obtained from the theoretical and conventional approaches.

  5. 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.

  6. Pile Driving Analysis for Pile Design and Quality Assurance

    Science.gov (United States)

    2017-08-01

    Driven piles are commonly used in foundation engineering. The most accurate measurement of pile capacity is achieved from measurements made during static load tests. Static load tests, however, may be too expensive for certain projects. In these case...

  7. FIELD INVESTIGATIONS OF PILED-RAFT FOUNDATIONS WITH SHORT-LENGTH CONIC PILES IN BUILDING AREAS OF MINSK

    Directory of Open Access Journals (Sweden)

    V. A. Sernov

    2015-01-01

    Full Text Available In recent time piled foundations are extensively applied due to an increase of storeys in buildings constructed in Minsk and load increment on the soil. Preference is given to this approach even in the case when relatively firm soil occurs in the top part of the foundation bed. In this case maximum usage of the foundation bed bearing capacity and reduction of foundation cost are considered as top-priority tasks for designers. One of the ways to increase the bearing capacity of piled foundations is the necessity to take into account resistance of foundation bed soil located under raft bottom. The raft as well as a shallow foundation is capable to transfer a significant part of building load into the soil. Such approach makes it possible to reduce a number of piles in the foundation or shorten their length. Then it results in shortening of the construction period and significant reduction in zero cycle. However up to the present moment reliable calculation methods that permit to take into account soil resistance in the raft base. An analysis of previous investigations on the matter executed by various researchers and a number of field investigations have been carried out with the purpose to develop the proposed methods.The paper presents results of field investigations on foundations consisting of short stamped tapered piles which are joined together with the help of the raft fragment. Strength and deformation characteristics of the bases are increasing while making such foundations in the fill-up soil. In this case the filled-up ground layer becomes a bearing layer both for piles and rafts as well. Improvement of high-plastic clay-bearing soil properties is ensured by ramming dry concrete mix under pile foot. The paper describes an experience on application of the piled-raft foundation in complicated engineering and geological conditions while constructing the Orthodox Church in Minsk.

  8. Uranium absorption study pile

    International Nuclear Information System (INIS)

    Raievski, V.; Sautiez, B.

    1959-01-01

    The report describes a pile designed to measure the absorption of fuel slugs. The pile is of graphite and comprises a central section composed of uranium rods in a regular lattice. RaBe sources and BF 3 counters are situated on either side of the center. A given uranium charge is compared with a specimen charge of about 560 kg, and the difference in absorption between the two noted. The sensitivity of the equipment will detect absorption variations of about a few ppm boron (10 -6 boron per gr. of uranium) or better. (author) [fr

  9. Technology of pile dynamic testing

    OpenAIRE

    Holeyman, Alain; The 4th International Conference on the Application of Stress-Wave Theory to Piles

    1992-01-01

    Because of the recent larger availability and higher performance of pile testing and monitoring equipment, pile dynamic testing has become part of many present day civil engineering projects. This report covers the past and state-of-the-art technological aspects of pile dynamic testing: testing methods, loading equipment, and measurements, including their acquisition and interpretation. Three major pile dynamic testing methods are distinguished based on means and objectives: high-strain testi...

  10. Characterizing hand-piled fuels

    Science.gov (United States)

    Clinton S. Wright; Paige C. Eagle; Cameron S. Balog

    2010-01-01

    Land managers throughout the West pile and burn surface fuels to mitigate fire hazard in dry forests. Whereas piling was historically conducted with heavy machinery following commercial harvesting operations, land managers are increasingly prescribing the use of hand piling and burning to treat surface fuels created by thinning and brush cutting. An estimate of the...

  11. Research on Bored Bearing Characteristics in Xi’an

    Directory of Open Access Journals (Sweden)

    Zhang Lipeng

    2015-01-01

    Full Text Available To analyze the influence of different soil properties on pile foundation load-bearing characteristics, taking a section of railway in Xi’an and a bridge of Xi’an as test area, and by field static load test to study load transfer characteristics after the test piles under axial pressure, including the distribution of axial force, pile lateral friction, tip resistance traits, ultimate bearing capacity determine, and compare with the theory bearing capacity. Experimental results show that, adjacent soil properties change large, axial force and lateral friction mutation at the junction of corresponding soil layer. Silty clay in different parts is below ground, and its lateral friction plays much difference. Pile lateral friction plays an important role in bearing capacity, but the role of round gravel soil end bearing capacity to pile bearing capacity can’t be ignored. Tests calculate pile bearing capacity significantly larger than standardized formula calculation bearing capacity, which are respectively 55.35% and 119.1%. And give the similar project condition the suggested values of pile bearing capacity and soil friction, to provide reference for similar pile foundation design.

  12. Test Exponential Pile

    Science.gov (United States)

    Fermi, Enrico

    The Patent contains an extremely detailed description of an atomic pile employing natural uranium as fissile material and graphite as moderator. It starts with the discussion of the theory of the intervening phenomena, in particular the evaluation of the reproduction or multiplication factor, K, that is the ratio of the number of fast neutrons produced in one generation by the fissions to the original number of fast neutrons, in a system of infinite size. The possibility of having a self-maintaining chain reaction in a system of finite size depends both on the facts that K is greater than unity and the overall size of the system is sufficiently large to minimize the percentage of neutrons escaping from the system. After the description of a possible realization of such a pile (with many detailed drawings), the various kinds of neutron losses in a pile are depicted. Particularly relevant is the reported "invention" of the exponential experiment: since theoretical calculations can determine whether or not a chain reaction will occur in a give system, but can be invalidated by uncertainties in the parameters of the problem, an experimental test of the pile is proposed, aimed at ascertaining if the pile under construction would be divergent (i.e. with a neutron multiplication factor K greater than 1) by making measurements on a smaller pile. The idea is to measure, by a detector containing an indium foil, the exponential decrease of the neutron density along the length of a column of uranium-graphite lattice, where a neutron source is placed near its base. Such an exponential decrease is greater or less than that expected due to leakage, according to whether the K factor is less or greater than 1, so that this experiment is able to test the criticality of the pile, its accuracy increasing with the size of the column. In order to perform this measure a mathematical description of the effect of neutron production, diffusion, and absorption on the neutron density in the

  13. 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.

  14. Simplified calculation methods for all-vertical-piled wharf in offshore deep water

    Science.gov (United States)

    Wang, Yuan-zhan; He, Lin-lin

    2017-04-01

    All-vertical-piled wharf is a kind of high-piled wharf, but it is extremely different from the traditional ones in some aspects, such as the structural property, bearing characteristics, failure mechanism, and static or dynamic calculation methods. In this paper, the finite element method (FEM) and theoretical analysis method are combined to analyze the structural property, bearing behavior and failure mode of the all-vertical-piled wharf in offshore deep water, and to establish simplified calculation methods determining the horizontal static ultimate bearing capacity and the dynamic response for the all-vertical-piled wharf. Firstly, the bearing capability and failure mechanism for all-vertical-piled wharf are studied by use of FEM, and the failure criterion is put forward for all-vertical-piled wharf based on the `plastic hinge'. According to the failure criterion and P-Y curve method, the simplified calculation method of the horizontal static ultimate bearing capacity for all-vertical-piled wharf is proposed, and it is verified that the simplified method is reasonable by comparison with the FEM. Secondly, the displacement dynamic magnification factor for the all-vertical-piled wharf under wave cyclic loads and ship impact loads is calculated by the FEM and the theory formula based on the single degree of freedom (SDOF) system. The results obtained by the two methods are in good agreement with each other, and the simplified calculation method of the displacement dynamic magnification factor for all-vertical-piled wharf under dynamic loads is proposed. Then the simplified calculation method determining the dynamic response for the all-vertical-piled wharf is proposed in combination with P-Y curve method. That is, the dynamic response of the structure can be obtained through the static calculation results of P-Y curve method multiplied by the displacement dynamic magnification factor. The feasibility of the simplified dynamic response method is verified by

  15. Construction technology of high-rise pile cap foundation of offshore wind power in Taiwan Strait

    Science.gov (United States)

    Li, C. Y.; Chi, Y.; Sun, X. Q.; Han, Y. P.; Chen, X.; Zhao, L. C.; Zhang, H.

    2017-11-01

    Offshore wind farms promise to become an important source of energy in the near future. The high-rise pile cap foundation is one of the typical foundation types for offshore wind turbine. This paper introduces the structural characteristics and construction technology of high-rise pile cap foundation, aiming at the characteristics of the sea area of Taiwan Strait and combining with engineering examples. The construction technology of high-rise pile cap foundation is expounded emphatically from the manufacture and transportation of steel pipe piles, pile foundation construction and bearing platform construction. Compared with the traditional construction technology, the construction technologies used in this project are safer and more reliable. The construction period of piles cap foundation is shortened by 10 ∼ 48 days. The construction technology provides reference for offshore wind power foundation construction.

  16. Stress Analysis of CFG Pile Composite Foundation in Consolidating Saturated Mine Tailings Dam

    Directory of Open Access Journals (Sweden)

    Jinxing Lai

    2016-01-01

    Full Text Available Cement fly-ash gravel (CFG pile is a widely used ground reinforcement technique. This paper aims to address the mechanical characteristics of CFG composite foundation in consolidating saturated mine tailings (MTs dam. The field static load tests were employed to explore the bearing capacity of the CFG composite foundation, and finite element (FE models in three dimensions validated through comparison with experimental results were used to discuss the pile-soil stress distribution and pile-soil stress ratio of the CFG composite foundation. The results indicate that the distribution of earth pressure and pile stress is relatively homogeneous and stable over depth and load, while the development of CFG composite foundation bearing capacity is insufficient, in which the developed bearing capacity of CFG piles is less than 50% of its characteristic value. Additionally, compared with the laboratory model test results, the pile-soil stress ratio decreases with the increasing of the load in FEM results proved to better conform to the actual engineering conditions. Furthermore, the deformation modulus and thickness of cushion exert significant influence on pile-soil stress ratio and integral bearing capacity of CFG composite foundation.

  17. THE RELIABILITY ANALYSIS OF EXISTING REINFORCED CONCRETE PILES IN PERMAFROST REGIONS

    Directory of Open Access Journals (Sweden)

    Vladimir S. Utkin

    2017-06-01

    Full Text Available The article describes the general problem of safe operation of buildings and structures with the dynamics of permafrost in Russia and other countries. The global warming on Earth will lead to global disasters such as failures of buildings and structures. The main reason of these failures will be a reduction of bearing capacity and the reliability of foundations. It is necessary to organize the observations (monitoring for the process of reducing the bearing capacity of foundations to prevent such accidents and reduce negative consequences, to development of preventive measures and operational methods for the piles reliability analysis. The main load-bearing elements of the foundation are reinforced concrete piles and frozen ground. Reinforced concrete piles have a tendency to decrease the bearing capacity and reliability of the upper (aerial part and the part in the soil. The article discusses the problem of reliability analysis of existing reinforced concrete piles in upper part in permafrost regions by the reason of pile degradation in the contact zone of seasonal thawing and freezing soil. The evaluation of the probability of failure is important in itself, but also it important for the reliability of foundation: consisting of piles and frozen soil. Authors offers the methods for reliability analysis of upper part of reinforced concrete piles in the contact zone with seasonally thawed soil under different number of random variables (fuzzy variables in the design mathematical model of a limit state by the strength criterion.

  18. Mono pile foundation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lyngesen, S.; Brendstrup, C.

    1997-02-01

    The use of mono piles as foundations for maritime structures has been developed during the last decades. The installation requirements within the offshore sector have resulted in equipment enabling driving of piles up to 3-4 m to large penetration depths. The availability of this equipment has made the use of large mono piles feasible as foundations for structures like wind turbines. The mono pile foundations consists of three parts; the bare pile, a conical transition and a boat landing. All parts are prefitted at the yard in order to minimise the installation work that has to be carried out offshore. The study of a mono pile foundations for a 1.5 MW wind turbine has been conducted for two locations, Horns Rev and Roedsand. Three different water depths: 5, 8 and 11 m have been investigated in the study. The on-site welding between pile and conical transition is performed by an automatic welding machine. Final testing and eventually repair of the weld are conducted at least 16 hours after welding. This is followed by final installation of J-tube, tie-in to subsea cables and installation of the impressed current system for corrosive protection of the mono pile. The total cost for procurement and installation of the mono pile using the welded connection is estimated. The price does not include procurement and installation of access platform and boat landing. These costs are estimated to 250.000 DKK. Depending on water depth the cost of the pile ranges from 2,2 to 2,7 million DKK. Procurement and fabrication of the pile are approx. 75% of the total costs. The remaining 25% are due to installation. The total costs are very sensitive to the unit price of pile steel. During the project it became obvious that ice load has a very large influence on the dimensions of the mono pile. (EG)

  19. 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.

  20. Use of geothermal piles combined with pile foundations

    Directory of Open Access Journals (Sweden)

    Ivan Kuzytskyi

    2016-07-01

    Full Text Available The possibility of use of geothermal piles in conditions of cold climate is considered. Full-scale experiment is conducted for using this technology in Kiev. Obtained results testify about a possibility for using the system in conditions of Ukraine, but this technology requires more detailed study and simulation of multiannual cycle of use of geothermal piles 

  1. 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.

  2. Pile technology section, annual report for 1955

    Energy Technology Data Exchange (ETDEWEB)

    1956-03-15

    This report is the 1955 annual report from the Pile Technology Section at Hanford. It summarizes work on pile engineering, pile materials, physics research, metallurgy, and fuel technology, related to the production reactors at Hanford.

  3. 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.

  4. Development of a new simplified load testing method of a pile. Kui no shinsaika shikenho no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, H.; Maruyama, O. (Japan Railway Construction Public Corp., Tokyo (Japan)); Fujioka, T. (Chiyoda Corp., Tokyo (Japan)); Kato, H. (Daido Concrete Co. Ltd., Tokyo (Japan))

    1992-10-15

    It is preferable to use a vertically loading test to verify bearing power of a pile. However, the conventional standard loading test could not be used easily because of much expense required for reactive piles and a loading device. Accordingly, a new load testing method was developed. The method places a load on a jack mounted initially near a pile tip, and measures the load on the jack, its vertical displacement and the strain and displacement in the pile including the pile head at each depth. Thus, the relationship between circumferential friction force at each part of the pile and the displacement, and the relationship between the jack load and the downward displacement are derived, which are converted to the relationship between the load on the pile head against the pile head loading and the amount of subsidence, using a load transmission analysis. The method features no necessity of reactive piles or loading girders, capability of measuring separately the circumferential friction force and the tip bearing power, safety, short construction time, and inexpensiveness. The jacks include types that are recovered after a test and not recovered. This new load testing method has been used on 18 different kinds of piles, in addition to verification test at sandy alluvial fan areas between Takasaki and Karuizawa in the planned Hokuriku Shinkansen line. 11 figs.

  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 labor...

  6. Adaptação de métodos semi-empíricos para estimar capacidade de carga de estacas de pequeno diâmetro no solo de Londrina, Estado do Paraná = Adaptation of the semi-empiric methods to calculate small diameter piles bearing capacity in the soil of Londrina City, Paraná State

    Directory of Open Access Journals (Sweden)

    Miriam Gonçalves Miguel

    2005-07-01

    Full Text Available A cidade de Londrina, Estado do Paraná, possui um perfil geotécnicoconstituído de uma camada superficial de solo argilo-siltoso, poroso, laterítico e muitas vezes colapsível, que se estende até a profundidade máxima de 12 metros. As estacas utilizadas em obras de pequeno a médio porte se encontram totalmente embutidas nesta camada, sofrendo a influência de seu comportamento laterítico e colapsível. Os métodos clássicos brasileiros de estimativa de capacidade de carga de estacas tornam-se conservadores, frente aos resultados reais, quando aplicados em solos lateríticos e, contra a segurança, quando aplicados em solos colapsíveis, isto é, na condição crítica ao colapso. Este trabalho avalia os coeficientes de ajuste das resistências de ponta e ao atrito lateral para esses métodos, no caso de estacas apiloadas, sendo estes coeficientes obtidos pela retro-análise de resultados de provas de carga estática à compressão, realizadas no Campo Experimental de Engenharia Geotécnica da Universidade Estadual de Londrina.The city of Londrina, Paraná, has a typical geotechnical profile defined by a superficial layer of porous silty clay with maximum depth of about 12 meters, that shows lateritic characteristics, andmany times, collapsibility. Casts in place piles are often used for small buildings in the region and are fully embedded in this soil layer. Therefore, this type of foundation is subjected to the lateritic and occasionally collapsible influence of soil. Brazilian pile bearing capacity methods may yield conservative results when applied to tropical soils, as far as the lateritic origin in concerned. On the other hand, it can be unsafe if collapsibility prevails. This paper evaluates coefficients to adjust both point and lateral resistance of cast in place small diameter piles in the situation described. The work was carried out at the Londrina State University Geotechnical Experimental Site, and back analysis from static

  7. Bore pile foundation tall buildings closed in the heritage building

    Science.gov (United States)

    Triastuti, Nusa Setiani

    2017-11-01

    Bore pile foundation for high building surroundings heritage building should be not damage. Construction proses must good, no necking, no mixed deep water, no sliding soil, nonporous concrete. Objective the execution of bore pile so that heritage buildings and neighboring buildings that are old do not experience cracks, damage and tilting. The survey methodology was observe the process of the implementation of the dominant silt, clay soil, in addition a limited space and to analyze the results of loading tests, investigations of soil and daily reports. Construction process determines the success of the structure bore pile in high building structure bearing, without damaging a heritage building. Attainment the hard soil depth, density concrete, observable clean reinforcement in the implementation. Monitoring the implementation of, among others, the face of the ground water little reduce in the area and outside the footprint of the building, no impact of vibration drilling equipment, watching the mud content on the water coming out at the time of drilling, concrete volume was monitored each 2 m bore depth of pile, The result researched heritage building was not damage. The test results bore pile axial, lateral analyzed the results have the appropriate force design required.

  8. Study on Dynamic Characteristics of Heavy Machine Tool-Composite Pile Foundation-Soil

    Directory of Open Access Journals (Sweden)

    CAI Li-Gang

    2014-09-01

    Full Text Available Heavy duty computer numerical control machine tools have characteristics of large self-weight, load and. The insufficiency of foundation bearing capacity leads to deformation of lathe bed, which effects machining accuracy. A combined-layer foundation model is created to describe the pile group foundation of multi-soil layer in this paper. Considering piles and soil in pile group as transversely isotropic material, equivalent constitutive relationship of composite foundation is constructed. A mathematical model is established by the introduction of boundary conditions, which is based on heavy duty computer numerical control machine tools-composite pile foundation-soil interaction system. And then, the response of different soil and pile depth is studied by a case. The model improves motion accuracy of machine tools.

  9. Seismic response of pile foundations and pile forces caused by kinematic and inertial interaction

    International Nuclear Information System (INIS)

    Hartmann, H.G.; Waas, G.

    1985-01-01

    The horizontal motion and pile forces of pile groups subjected to earthquake excitation are analysed. The piles are modelled as linear elastic beam elements embedded in a layered linear visco-elastic soil medium. Pile-soil-pile interaction is included. The earthquake excitation results from vertically propagating shear waves. Kinematic and inertial interaction effects on foundation motion and pile forces are studied for a single pile, a small pile group and a large pile group. Soft and stiff soil conditions are considered, and the effect of a flexible vs. a rigid halfspace below the soil layers is shown. (orig.)

  10. Polar bear use of a persistent food subsidy: insights from non-invasive genetic sampling in Alaska

    Science.gov (United States)

    Peacock, Elizabeth; Herreman, Jason

    2013-01-01

    Remains of bowhead whales (Balaena mysticetus) harvested by Iñupiat whalers are deposited in bone piles along the coast of Alaska and have become persistent and reliable food sources for polar bears (Ursus maritimus). The importance of bone piles to individuals and the population, the patterns of use, and the number, sex, and age of bears using these resources are poorly understood. We implemented barbed-wire hair snaring to obtain genetic identities from bears using the Point Barrow bone pile in winter 2010–11. Eighty-three percent of genotyped samples produced individual and sex identification. We identified 97 bears from 200 samples. Using genetic mark–recapture techniques, we estimated that 228 bears used the bone pile during November to February, which would represent approximately 15% of the Southern Beaufort Sea polar bear subpopulation, if all bears were from this subpopulation. We found that polar bears of all age and sex classes simultaneously used the bone pile. More males than females used the bone pile, and males predominated in February, likely because 1/3 of adult females would be denning during this period. On average, bears spent 10 days at the bone pile (median  =  5 days); the probability that an individual bear remained at the bone pile from week to week was 63% for females and 45% for males. Most bears in the sample were detected visiting the bone pile once or twice. We found some evidence of matrilineal fidelity to the bone pile, but the group of animals visiting the bone pile did not differ genetically from the Southern Beaufort Sea subpopulation, nor did patterns of relatedness. We demonstrate that bowhead whale bone piles may be an influential food subsidy for polar bears in the Barrow region in autumn and winter for all sex and age classes.

  11. Underwater noise reduction of marine pile driving using a double pile.

    Science.gov (United States)

    2015-12-01

    Impact pile driving of steel piles in marine environments produces extremely high sound levels in the water. : It has been shown that current pile driving noise attenuation techniques, such as bubble curtains and : cofferdams, provide limited noise r...

  12. Energy piles. A fundamental energy pile; Energiepfaehle. Eine fundamentale Energiequelle

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Holger; Beldermann, Nico [GF-Tec GmbH, Roedermark (Germany)

    2013-03-01

    The Maintower, the new airport in Berlin/Brandenburg, a lot of Ikea buildings, and also small office buildings or residential buildings may exchange energy with the underground by means of pile fundaments. At the correct planning and execution, energy piles are low-cost geothermal power plants which sustainable generate heating and cooling for the buildings standing on them. Even more energy can be generated safely under compliance with the groundwater protection by means of a new development of the material and the transfer.

  13. Design Implementation of Pile Foundation

    OpenAIRE

    Jaiswal, Manish

    2017-01-01

    The objective of this Bachelor’s thesis was to design a pile foundation for a residential building. The aim was to identify aspects affecting pile foundation design in a challenging environment because the building was to be built on a reclaimed land from the Baltic sea and almost half of the foundation slab would extend into the sea, resulting in very high lateral forces due to ice loading during winter. The site was to be stabilised using deep soil mixing columns. To enable the design,...

  14. Experiment of the bottle pile

    International Nuclear Information System (INIS)

    Mazancourt, R. de

    1957-10-01

    After a presentation of the experimental conditions (pile status and condition, atmospheric conditions and detector locations, establishment of flux maps), the authors reports the performed data analysis: general principles, least square method, graphical determination. Results are discussed in the case of gold (analysis of rough counts, analysis after extraction of the second harmonic) and indium (rough counts, cadmium rate)

  15. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 4B : material & construction specifications : final report.

    Science.gov (United States)

    2015-07-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 4B, Materials and Construction Specifications. : This technical report...

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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...

  2. Modeling of Batter Pile Behavior under Lateral Soil Movement

    Science.gov (United States)

    Chen, C. Y.; Hsu, H. Q.

    2017-06-01

    Pile foundation is frequently used when structures are located on weak sublayers or are at risk from lateral loadings such as earthquakes. The design of pile foundations has recently become crucial to stop slope movement. To understand the behavior of pile foundations subjected to lateral soil movement, the three-dimensional Fast Lagrangian Analysis of Continua (FLAC3D) program was used to perform numerical simulations, which can reduce the cost of field testing. Vertical piles and batter piles were combined into 3 × 3 pile groups, and the response of batter piles to soil movement was analyzed. The outer batter piles led to an increased bending moment in the middle, vertical pile row. Increasing the pile spacing and the presence of battered piles reduced the pile group’s displacement. The batter pile group’s maximum bending moment was smaller than the vertical pile group’s in sand soil, but 5-8 times higher in clay soil.

  3. Geology and hydrology in the vicinity of the inactive uranium mill tailings pile, Ambrosia Lake, New Mexico

    International Nuclear Information System (INIS)

    Purtymun, W.D.; Wienke, C.L.; Dreesen, D.R.

    1977-06-01

    A study was made of the geology and hydrology of the immediate area around a uranium mill at Ambrosia Lake, New Mexico. The mill was in operation from June 1958 through April 1963 and produced 2.7 x 10 9 kg of tailings. The possible environmental consequences of this inactive tailings pile must first be delineated so that stabilization needs and future stabilization success can be properly assessed. The Ambrosia Lake area is underlain by over 1000 m of alternating shales, siltstones, and sandstones that dip gently to the northeast into the San Juan Basin. Water-bearing sandstones make up less than 25 percent of this sedimentary section. Water quality in the sandstones is fair to poor, with total dissolved solids ranging from 500 to 2000 mg/l. The present total volume of tailings is estimated at 1.5 x 10 6 m 3 and ranges in thickness from about 1 to 10 m. The tailings pile is underlain by the Mancos shale which dips to the northeast. The shale is about 120 m thick with three interbedded silty sandstones that are about 9 m in thickness. One of these sandstones outcrops beneath the western part of the pile; the eastern part of the pile is underlain by shale. Ground water in the shales and sandstones beneath the pile is recharged by runoff north of the pile and from three ponds located north, northeast, and east of the pile. The movement of water in shale and sandstones is to the southwest. Secondary recharge to the water in the shales and sandstone is from the basin within the tailings pile. Water in the southeast part of the tailings basin is forming a ground water mound above the underlying sediments. The major transport mechanisms of tailings and possible contaminants from the pile include wind erosion, surface water runoff, movement of ground water beneath the pile, and gaseous diffusion from the pile

  4. Undrained behavior of auger cast-in-place piles in multilayered soil

    Directory of Open Access Journals (Sweden)

    Fathi M. Abdrabbo

    2013-06-01

    Full Text Available Auger cast-in-place piles (ACIP are often installed through multilayered soil profiles, which make accurate predictions of the performance of the piles more complex than piles constructed in either clay or sand deposits. This study is intended to shed some light on the undrained behavior of ACIP embedded in stratified soil and to explore a methodology to predict the ultimate pile loads. The study is based on practical measurements of load–displacement relationships of 51 static loading tests of full-scale ACIP installed through multilayered soil profiles. The study revealed that the normalized load–displacement relationships of the tested piles have deterministic range with upper and lower bounds. Equations for these bounds and the mean load–displacement relationship are developed in this study. There is a deficiency in the literature concerning the calculations of ultimate loads for piles embedded in multilayered soil. Therefore, this paper presents an attempt to estimate the ultimate pile load in undrained conditions utilizing two approaches. The first approach assumed the failure pattern of the soil beneath the pile base to be punching into the sand followed by general shear failure in clay underneath. The end-bearing resistance at the pile tip was estimated by implementing Meyerhof and Hanna’s [24] shallow foundation procedure. The second approach assessed the depth of the influence zone below the pile tip using isobars of pressure around and below the pile tip due to a point load, based on the theory of elasticity and characterization of a semi-infinite soil mass (Martins [3]. Soil layers, within the zone of influence, were considered to be an equivalent geomaterial with shear strength parameters computed by weighted average of shear strength parameters of the soil sub-layers. For comparison purposes, the ultimate pile load of each test was interpreted experimentally using the method proposed by Chin (1970. Reasonable agreement was

  5. Application of a distributed optical fiber sensing technique in monitoring the stress of precast piles

    International Nuclear Information System (INIS)

    Lu, Y; Shi, B; Wei, G Q; Zhang, D; Chen, S E

    2012-01-01

    Due to its ability in providing long distance, distributed sensing, the optical fiber sensing technique based on a Brillouin optical time domain reflectometer (BOTDR) has a unique advantage in monitoring the stability and safety of linear structures. This paper describes the application of a BOTDR-based technique to measure the stress within precast piles. The principle behind the BOTDR and the embedding technique for the sensing optical fiber in precast piles is first introduced, and then the analysis method and deformation and stress calculation based on distributed strain data are given. Finally, a methodology for using a BOTDR-based monitoring workflow for in situ monitoring of precast piles, combined with a practical example, is introduced. The methodology requires implantation of optical fibers prior to pile placement. Field experimental results show that the optical fiber implantation method with slotting, embedding, pasting and jointing is feasible, and have accurately measured the axial force, side friction, end-bearing resistance and bearing feature of the precast pile according to the strain measuring data. (paper)

  6. Steel Sheet Pile Walls in Soft Soil

    OpenAIRE

    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 issued in 1997. This code offers possibilities for cheaper and safer steel sheet piling, in comparison with the existing design criteria used in most countries. Two of these design criteria with w...

  7. Hydraulic structures with defective sheet pile walls

    OpenAIRE

    Ahmed, Ashraf A.; Johnston, Harold T.; Oyedele, Lukumon

    2013-01-01

    A sheet pile wall driven to form a barrier wall below the floor of a hydraulic structure is frequently assumed to be watertight. Although the leakage through the interlocks of the sheet piles is usually small, damage and other factors can result in significant leakage. Consequently, this assumption is rarely, if ever, satisfied in reality. The present study used a finite-element model to investigate the effect of leaks through sheet piles driven under the floor of a hydraulic structure on see...

  8. Characterizing Axial Stiffness of Individual Batter Piles with Emphasis on Elevated, Laterally Loaded, Clustered Pile Groups

    Science.gov (United States)

    2016-11-01

    mudline. The piles are 2 ft diameter, concrete-filled pipe piles. Fortunately, the CPGA software discussed subsequently had enough flexibility to...being an axial stiffness modifier, A designating the cross-sectional area of the concrete-filled pipe pile, E designating the pile’s (composite...stiffness modifier, A designates the cross-sectional area of the concrete-filled pipe pile, E designates its (composite) Young’s Modulus, and Le is the

  9. Underwater Sound Propagation from Marine Pile Driving.

    Science.gov (United States)

    Reyff, James A

    2016-01-01

    Pile driving occurs in a variety of nearshore environments that typically have very shallow-water depths. The propagation of pile-driving sound in water is complex, where sound is directly radiated from the pile as well as through the ground substrate. Piles driven in the ground near water bodies can produce considerable underwater sound energy. This paper presents examples of sound propagation through shallow-water environments. Some of these examples illustrate the substantial variation in sound amplitude over time that can be critical to understand when computing an acoustic-based safety zone for aquatic species.

  10. Use of pile driving analysis for assessment of axial load capacity of piles : [technical summary].

    Science.gov (United States)

    2012-01-01

    The dynamic response of a pile during driving is very : complex, involving the interactions of the hammer, cushion, : pile and soil during application of an impact load. : The first analysis aimed at simulating a hammer blow on : a pile was published...

  11. Bearing system

    Science.gov (United States)

    Kapich, Davorin D.

    1987-01-01

    A bearing system includes backup bearings for supporting a rotating shaft upon failure of primary bearings. In the preferred embodiment, the backup bearings are rolling element bearings having their rolling elements disposed out of contact with their associated respective inner races during normal functioning of the primary bearings. Displacement detection sensors are provided for detecting displacement of the shaft upon failure of the primary bearings. Upon detection of the failure of the primary bearings, the rolling elements and inner races of the backup bearings are brought into mutual contact by axial displacement of the shaft.

  12. 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

  13. Detection of tube leaks in piles

    Energy Technology Data Exchange (ETDEWEB)

    Upson, U.L.

    1960-01-20

    This report discusses the use of liquid ammonia as a tracer for the detection of cooling water leaks into the piles. It is both safe and cheap and can be detected by methods adaptable to direct-reading instrumentation on a continuous-flow sample. Moderate capital costs and materials costs of less than $50 per pile test are anticipated.

  14. Design method of large-diameter rock-socketed pile with steel casing

    Science.gov (United States)

    Liu, Ming-wei; Fang, Fang; Liang, Yue

    2018-02-01

    There is a lack of the design and calculation method of large-diameter rock-socketed pile with steel casing. Combined with the “twelfth five-year plan” of the National Science & Technology Pillar Program of China about “Key technologies on the ports and wharfs constructions of the mountain canalization channels”, this paper put forward the structured design requirements of concrete, steel bar distribution and steel casing, and a checking calculation method of the bearing capacity of the normal section of the pile and the maximum crack width at the bottom of the steel casing. The design method will have some degree of guiding significance for the design of large-diameter rock-socketed pile with steel casing.

  15. An analysis of the static load test on single square pile of 40x40 cm2, using finite element method in Rusunawa project, Jatinegara, Jakarta

    Science.gov (United States)

    Harasid, Harun; Roesyanto; Iskandar, Rudi; Silalahi, Sofyan A.

    2018-03-01

    Piling Foundation is one of the foundations which is used to penetrate its load through soil layer. The power carried by the piling is obtained from the end bearing capacity, that is, the compressive end piling and friction bearing capacity obtained from friction bearing and adhesive capacity between the piling and the soil around it. The investigation on the Standard Penetration Test is aimed to get the description of soil layer, based on the type and color of soil through visual observation, and soil characteristics. SPT data can be used to calculate bearing capacity. Besides investigating the SPT, this study is also been equipped by taking the samples in laboratory and loading test on the piling and Ducth Cone Penetrometer (DCP) data to confirm its bearing capacity. This study analyzed bearing capacity and settlement in the square pile of 40X40 cm in diameter in a single pile or grouped, using an empirical method, AllPile program, Plaxis program, and comparing the result with interpreting its loading test in the foundation of Rusunawa project, Jatinegara, Jakarta. The analysis was been done by using the data on soil investigation and laboratory by comparing them with Mohr-Coulomb soil model. Ultimate bearing capacity from the SPT data in the piling of 15.4 meters was 189.81 tons and the parameter of soil shear strength was 198.67 tons. The sander point, based on Aoki and De Alencar bearing capacity was 276.241 tons and based on Mayerhoff it was 305.49 tons. Based on the loading test of bearing capacity, unlimited bearing capacity for the three methods was Davisson (260 tons), Mazurkiewich (270 tons), and Chin (250 tons). The efficiency of grouped piles according to Converse-Library Equation method = 0.73, according to Los Angeles Group Action Equation method = 0.59, and according to Sheila-Keeny method = 0.94. Bearing capacity based on piling strength was 221.76 tons, bearing capacity based on calendaring data was 201.71 tons, and lateral bearing capacity of a

  16. 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

  17. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 7 : final report : thesis.

    Science.gov (United States)

    2015-05-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 7, Final Report - Thesis. : This final report covers Tasks 1, 2, 3, 5 ...

  18. Neural networks and principle component analysis approaches to predict pile capacity in sand

    Directory of Open Access Journals (Sweden)

    Benali A

    2018-01-01

    Full Text Available Determination of pile bearing capacity from the in-situ tests has developed considerably due to the significant development of their technology. The project presented in this paper is a combination of two approaches, artificial neural networks and main component analyses that allow the development of a neural network model that provides a more accurate prediction of axial load bearing capacity based on the SPT test data. The retropropagation multi-layer perceptron with Bayesian regularization (RB was used in this model. This was established by the incorporation of about 260 data, obtained from the published literature, of experimental programs for large displacement driven piles. The PCA method is proposed for compression and suppression of the correlation between these data. This will improve the performance of generalization of the model.

  19. Reliability-Based Design and Quality Control of Bored Piles

    NARCIS (Netherlands)

    Bach, D.

    2014-01-01

    Bored piles are a type of deep foundations which have been and are being widely used in construction engineering such as high-rise buildings, bridges, jetties, and so on. Although bored piles have remarkable advantages over driven piles, the quality of bored piles is frequently affected by many

  20. Soil heating during burning of forest slash piles and wood piles

    Science.gov (United States)

    Matt D. Busse; Carol J. Shestak; Ken R. Hubbert

    2013-01-01

    Pile burning of conifer slash is a common fuel reduction practice in forests of the western United States that has a direct, yet poorly quantified effect on soil heating. To address this knowledge gap, we measured the heat pulse beneath hand-built piles ranging widely in fuel composition and pile size in sandy-textured soils of the Lake Tahoe Basin. The soil heat pulse...

  1. Modeling Laterally Loaded Single Piles Accounting for Nonlinear Soil-Pile Interactions

    Directory of Open Access Journals (Sweden)

    Maryam Mardfekri

    2013-01-01

    Full Text Available The nonlinear behavior of a laterally loaded monopile foundation is studied using the finite element method (FEM to account for soil-pile interactions. Three-dimensional (3D finite element modeling is a convenient and reliable approach to account for the continuity of the soil mass and the nonlinearity of the soil-pile interactions. Existing simple methods for predicting the deflection of laterally loaded single piles in sand and clay (e.g., beam on elastic foundation, p-y method, and SALLOP are assessed using linear and nonlinear finite element analyses. The results indicate that for the specific case considered here the p-y method provides a reasonable accuracy, in spite of its simplicity, in predicting the lateral deflection of single piles. A simplified linear finite element (FE analysis of piles, often used in the literature, is also investigated and the influence of accounting for the pile diameter in the simplified linear FE model is evaluated. It is shown that modeling the pile as a line with beam-column elements results in a reduced contribution of the surrounding soil to the lateral stiffness of the pile and an increase of up to 200% in the predicted maximum lateral displacement of the pile head.

  2. Displacement pile installation effects in sand

    NARCIS (Netherlands)

    Beijer-Lundberg, A.

    2015-01-01

    Installation effects govern the post-installation behaviour of displacement piles in sand. These effects are currently not completely understood. Suitable experimental techniques to model these installation effects include field, laboratory and experimental models. In the current thesis a

  3. Performance of pile supported sign structures : [brief].

    Science.gov (United States)

    2015-05-01

    Sign structures in Wisconsin are typically supported by drilled shaft foundations or spread : footing foundations. However, when the soil conditions are not suitable to be supported on : drilled shafts or spread footings, a group of piles could suppo...

  4. New trends in pile safety instrumentation

    International Nuclear Information System (INIS)

    Furet, J.

    1961-01-01

    This report addresses the protection of nuclear piles against damages due to operation incidents. The author discusses the current trends in the philosophy of safety of atomic power piles, identifies the parameters which define safety systems, presents tests to be performed on safety chains, comments the relationship between safety and the decrease of the number of pile inadvertent shutdowns, discusses the issues of instrument failures and chain multiplicity, comments the possible improvement of the operation of elements which build up safety chains (design simplification, development of semiconductors, replacement of electromechanical relays by static relays), the role of safety logical computers and the development of automatics in pile safety, presents automatic control as a safety factor (example of automatic start-up), and finally comments the use of fuses

  5. ATLAS Pile-up and Overlay Simulation

    CERN Document Server

    Novak, Tadej; The ATLAS collaboration

    2017-01-01

    The high luminosity of the LHC results in a significant background to interesting physics events known as pile-up. ATLAS uses several methods for simulating the effects of pile-up. The mostly used method is a direct simulation of background events where multiple simulated background events are combined for each physics event. For some physics processes, a more accurate simulation can be achieved by overlaying real proton-proton collisions on a simulated hard-scatter process. Overlay is also being investigated for a premixed pile-up background to reduce CPU usage and I/O stress during the simulation. Embedding replaces the muons found in Z→mumu decays in data with simulated taus at the same 4-momenta, thus preserving the underlying event and pileup from the original data event. This talk compares the pile-up simulation methods used at the ATLAS experiment pointing their benefits and drawbacks.

  6. A simplified algorithm for the design of piled raft foundations applied for the case study of a building erected within Żoliborz-Szczęśliwice glacial tunnel valley

    Directory of Open Access Journals (Sweden)

    Kacprzak Grzegorz

    2015-06-01

    Full Text Available A common engineering solution for excessive settlement with raft foundation (s is the use of piles in order to reduce the vertical displacements, in this method, the whole structural load is transferred to the piles. This is an overly cautious approach, and there remains a need to find an optimal design method for a building’s foundations. Such a solution may be the piled raft foundation, which allows a reduction of the number of piles due to the integration of the raft in the bearing capacity of the foundation. The aim of the article is to estimate the contribution of foundation elements such as the raft and the piles in the bearing capacity of a residential building located in Warsaw, where the geological conditions are characterized by organic soil layers, principally of gyttja.

  7. Applicability of recycled aggregates in concrete piles for soft soil improvement.

    Science.gov (United States)

    Medeiros-Junior, Ronaldo A; Balestra, Carlos Et; Lima, Maryangela G

    2017-01-01

    The expressive generation of construction and demolition waste is stimulating several studies for reusing this material. The improvement of soft soils by concrete compaction piles has been widely applied for 40 years in some Brazilian cities. This technique is used to improve the bearing capacity of soft soils, allowing executing shallow foundations instead of deep foundations. The compaction piles use a high volume of material. This article explored the possibility of using recycled aggregates from construction waste to replace the natural aggregates in order to improve the bearing capacity of the soft soil, regarding its compressive strength. Construction wastes from different stages of a construction were used in order to make samples of concrete with recycled aggregates. The strength of concretes with natural aggregates was compared with the strength of concretes with recycled (fine and coarse) aggregates. Results show that all samples met the minimum compressive strength specified for compaction piles used to improve the bearing capacity of soft soils. The concrete with recycled aggregate from the structural stage had even higher resistances than the concrete with natural aggregates. This behaviour was attributed to the large amount of cementitious materials in the composition of this type of concrete. It was also observed that concrete with recycled fine aggregate has a superior resistance to concrete with recycled coarse aggregate.

  8. Grouting of uranium mill tailings piles

    International Nuclear Information System (INIS)

    Boegly, W.J. Jr.; Tamura, T.; Williams, J.D.

    1984-03-01

    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

  9. Numerical analysis for sea wave loading on the pile foundation of detached structures by using CADMAS-SURF

    Science.gov (United States)

    Matsuda, Tatsuya; Miura, Kinya; Sawada, Yayoi

    2017-10-01

    This study investigated the characteristics of wave forces loading on the detached structure that consisted of an upper structure and a pile foundation. In this study, structure stability was also considered on the results obtained from previous studies on the instability of seabed induced by wave force. When a wave force acted on the structure, an external force acted on the pile foundation as if pulling out the foundation on the outer harbor side and pushing it in on the inner harbor. The effective stress in seabed was increase so the pile foundation was considered to maintain sufficient bearing capacity. Subsequently, when the bearing capacity of the ground was decreased because the water pressure in the ground surface layer decreased, the pile foundation will be aggravated settled down. The external force acting on the pile foundation was not same on outer harbor and inner harbor with the form of the upper structure. As a result, we found that the strain will be generated on the structure.

  10. Magnetic Bearing

    OpenAIRE

    Anbuselvan. T; Vinothkumar. K; Sai Vikash. M

    2013-01-01

    The use of bearings is essential to all types of machines, especially in marine aspects they provide the function of supporting heavier component in a desired position. These bearings have contact with the rotating part and causes surface wear which can be controlled by lubrication. Researches have raised the standards of performance for rotating equipment by providing robust, cost effective, easy to implement magnetic bearing solutions. Use of magnetic bearings in ships can be more advantag...

  11. Journal bearing

    Science.gov (United States)

    Menke, John R.; Boeker, Gilbert F.

    1976-05-11

    1. An improved journal bearing comprising in combination a non-rotatable cylindrical bearing member having a first bearing surface, a rotatable cylindrical bearing member having a confronting second bearing surface having a plurality of bearing elements, a source of lubricant adjacent said bearing elements for supplying lubricant thereto, each bearing element consisting of a pair of elongated relatively shallowly depressed surfaces lying in a cylindrical surface co-axial with the non-depressed surface and diverging from one another in the direction of rotation and obliquely arranged with respect to the axis of rotation of said rotatable member to cause a flow of lubricant longitudinally along said depressed surfaces from their distal ends toward their proximal ends as said bearing members are rotated relative to one another, each depressed surface subtending a radial angle of less than 360.degree., and means for rotating said rotatable bearing member to cause the lubricant to flow across and along said depressed surfaces, the flow of lubricant being impeded by the non-depressed portions of said second bearing surface to cause an increase in the lubricant pressure.

  12. Measurement and Analysis of Horizontal Vibration Response of Pile Foundations

    Directory of Open Access Journals (Sweden)

    A. Boominathan

    2007-01-01

    Full Text Available Pile foundations are frequently used in very loose and weak deposits, in particular soft marine clays deposits to support various industrial structures, power plants, petrochemical complexes, compressor stations and residential multi-storeyed buildings. Under these circumstances, piles are predominantly subjected to horizontal dynamic loads and the pile response to horizontal vibration is very critical due to its low stiffness. Though many analytical methods have been developed to estimate the horizontal vibration response, but they are not well validated with the experimental studies. This paper presents the results of horizontal vibration tests carried out on model aluminium single piles embedded in a simulated Elastic Half Space filled with clay. The influence of various soil and pile parameters such as pile length, modulus of clay, magnitude of dynamic load and frequency of excitation on the horizontal vibration response of single piles was examined. Measurement of various response quantities, such as the load transferred to the pile, pile head displacement and the strain variation along the pile length were done using a Data Acquisition System. It is found that the pile length, modulus of clay and dynamic load, significantly influences the natural frequency and peak amplitude of the soil-pile system. The maximum bending moment occurs at the fundamental frequency of the soil-pile system. The maximum bending moment of long piles is about 2 to 4 times higher than that of short piles and it increases drastically with the increase in the shear modulus of clay for both short and long piles. The active or effective pile length is found to be increasing under dynamic load and empirical equations are proposed to estimate the active pile length under dynamic loads.

  13. 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...... to resemble full scale dimension of piles used in offshore pile foundations today. In this report is given a detailed description of the soil preparation and pile installation procedures as well data acquisition methods....

  14. Seismic behavior analysis of piled drums

    International Nuclear Information System (INIS)

    Aoki, H.; Kosaka, T.; Mizushina, T.; Shimizu, M.; Uji, S.; Tsuchiya, H.

    1987-01-01

    In general, low level radioactive waste is packed in drums and stored in a warehouse being piled vertically, or laid horizontally. To observe the behavior of piled drums during an earthquake, an experimental study was reported. The experimental study is limited by the vibrating platform capacity. To carry out these tests up to the supporting limit is not recommended, in view of the vibrating platform curing as well as the operators' security. It is very useful to develop the analytical method for simulating the behavior of the drums. In this report, a computer program of piled drum's dynamic motion is shown, and the analytical result is referred to the experimental result. From the result of experiment on piled drums, the sliding effect has been found to be very important for the stability of drum, and the rocking motion observed, showing a little acceleration is less than the static estimated value. Behavior of piled drums is a complex phenomena comprising of sliding, rocking and jumping

  15. GAS BEARING

    Science.gov (United States)

    Skarstrom, C.W.

    1960-09-01

    A gas lubricated bearing for a rotating shaft is described. The assembly comprises a stationary collar having an annular member resiliently supported thereon. The collar and annular member are provided with cooperating gas passages arranged for admission of pressurized gas which supports and lubricates a bearing block fixed to the rotatable shaft. The resilient means for the annular member support the latter against movement away from the bearing block when the assembly is in operation.

  16. Thrust bearing

    Science.gov (United States)

    Anderson, W. J. (Inventor)

    1976-01-01

    A gas lubricated thrust bearing is described which employs relatively rigid inwardly cantilevered spokes carrying a relatively resilient annular member or annulus. This annulus acts as a beam on which are mounted bearing pads. The resilience of the beam mount causes the pads to accept the load and, with proper design, responds to a rotating thrust-transmitting collar by creating a gas film between the pads and the thrust collar. The bearing may be arranged for load equalization thereby avoiding the necessity of gimbal mounts or the like for the bearing. It may also be arranged to respond to rotation in one or both directions.

  17. Radiation Protection in the Experimental Pile Marius

    International Nuclear Information System (INIS)

    Cohendy, G.

    1962-01-01

    Measurements made around the experimental pile 'Marius' made it possible to determine the valid characteristics of the slabs designed to improve the biological protection by covering the charge and discharge pits. These measurements also made it possible to evaluate the risks occurring when the pile is operating at various Powers and to make a reasonable estimate of the value of the ratio of the total danger due to neutrons (thermal and fast) and γ radiation and to the danger due only to the γ radiation. A knowledge of this ratio makes it possible to make satisfactory evaluations with a single apparatus which is really portable. (author) [fr

  18. Synthesis of concrete bridge piles prestressed with CFRP systems.

    Science.gov (United States)

    2017-06-01

    The Texas Department of Transportation frequently constructs prestressed concrete piles for use in bridge : foundations. Such prestressed concrete piles are typically built with steel strands that are highly susceptible to : environmental degradation...

  19. Reactor G1 - Flux charts in the flat pile

    International Nuclear Information System (INIS)

    Genthon, J.P.

    1957-10-01

    Experimental flux charts are available for different pile conditions. Data in these charts are given as points. The flux density at each point is the result of the irradiation and counting of a detector, followed by plotting of this count. All these flux density measurements are relative. The different flux charts studied are always relative to the fiat pile, loading side; this will give us: - the flat pile full for the Laplacian measurement; - the flat pile full for the study of the variation of the cadmium ratio; - the flat pile, central canal empty; - the flat pile, central canal plugged with graphite; - the flat pile, central canal containing a cadmium rod; - the flat pile, central canal containing a thorium rod. (author) [fr

  20. The effect of pile parameters on the factor of safety of piled-slopes using 3D numerical analysis

    Directory of Open Access Journals (Sweden)

    Ahmed Abdelaziz

    2017-12-01

    Full Text Available Slope stability can be achieved using different methods. Piles are commonly used to stabilize slopes or to improve slope stability. Stabilized slopes with piles are numerically studied in the current paper. A 3 dimensional (3D finite element study is carried out to investigate the effect of different parameters on the stability of slopes stabilized with piles. A 3D finite element model was developed using the finite element program PLAXIS. The 3D model was verified using experimental data from the literature for a stabilized silty sand slope in a large-scale physical model. A parametric study was undertaken to study the effect of pile position, pile inclination, pile length and pile diameter on the factor of safety of the piled-slopes. The findings of the research were compared to other findings from the literature. The results show that using the 3D aspect gives more insight into the complicated slope stability problem. The study determines the optimum location of the pile and its optimum inclination to achieve the maximum stability. It shows that after a certain length of the pile, increasing the pile length becomes unnecessary and that the diameter of the pile has a relatively minor effect on the factor of safety of piled-slopes.

  1. Polar Bears

    Science.gov (United States)

    Amstrup, Steven C.; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

    2002-01-01

    Polar bears (Ursus maritimus) are hunted throughout most of their range. In addition to hunting polar bears of the Beaufort Sea region are exposed to mineral and petroleum extraction and related human activities such as shipping road-building, and seismic testing (Stirling 1990).Little was known at the start of this project about how polar bears move about in their environment, and although it was understood that many bears travel across political borders, the boundaries of populations had not been delineated (Amstrup 1986, Amstrup et al. 1986, Amstrup and DeMaster 1988, Garner et al. 1994, Amstrup 1995, Amstrup et al. 1995, Amstrup 2000).As human populations increase and demands for polar bears and other arctic resources escalate, managers must know the sizes and distributions of the polar bear populations. Resource managers also need reliable estimates of breeding rates, reproductive intervals, litter sizes, and survival of young and adults.Our objectives for this research were 1) to determine the seasonal and annual movements of polar bears in the Beaufort Sea, 2) to define the boundaries of the population(s) using this region, 3) to determine the size and status of the Beaufort Sea polar bear population, and 4) to establish reproduction and survival rates (Amstrup 2000).

  2. Pile group program for full material modeling and progressive failure.

    Science.gov (United States)

    2008-12-01

    Strain wedge (SW) model formulation has been used, in previous work, to evaluate the response of a single pile or a group of piles (including its : pile cap) in layered soils to lateral loading. The SW model approach provides appropriate prediction f...

  3. 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 pi...

  4. Construction of Steel Pipe Sheet Piles with Newly Developed Joint ...

    African Journals Online (AJOL)

    H-joint in steel pipe sheet piles (SPSP) is introduced and developed, the joint is made by welding a cylindrical steel pile on either side of an H steel section, welding is continuous along their lengths therefore it is completely waterproof with high strength; the two connected piles are installed simultaneously hence short ...

  5. Application Study of Self-balanced Testing Method on Big Diameter Rock-socketed Piles

    Directory of Open Access Journals (Sweden)

    Qing-biao WANG

    2013-07-01

    Full Text Available Through the technological test of self-balanced testing method on big diameter rock-socketed piles of broadcasting centre building of Tai’an, this paper studies and analyzes the links of the balance position selection, the load cell production and installation, displacement sensor selection and installation, loading steps, stability conditions and determination of the bearing capacity in the process of self-balanced testing. And this paper summarizes key technology and engineering experience of self-balanced testing method of big diameter rock-socketed piles and, meanwhile, it also analyzes the difficult technical problems needed to be resolved urgently at present. Conclusion of the study has important significance to the popularization and application of self-balanced testing method and the similar projects.

  6. 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

  7. Laterally Loaded Partially Prestressed Concrete Piles

    Science.gov (United States)

    1989-09-01

    of an extensive test program onl laterali y ioadeu. partially pr- estressed concrete fender piles. The study Included service load range as well ats...12,000-psi design strength). Configura- tion G utilized 14 r:- estress strand, in an unsymmetric pattern. To provide a uniform concrete prestress of 540

  8. 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.

  9. 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

  10. Dynamic behaviour of raft and pile foundations tests and computational models. Pt. 1

    International Nuclear Information System (INIS)

    Betbeder, J.; Garnier, J.C.; Gauvain, J.; Jeandidier, C.

    1981-01-01

    Pile foundations are commonly used for many types of buildings where the bearing capacity of soil is poor. For nuclear power plants buildings, however, there seems to be a fairly general reluctancy to accept design on piles, as it is considered difficult to demonstrate the safety of these foundations with respect to earthquakes, due to the relative lack of validation of the currently available aseismic design methods. Being conscious that pile foundations might be worth considering for future nuclear sites in France and that the reliability of design methods should be backed by experimental data, ELECTRICITE DE FRANCE decided in 1978 to undertake a series of tests, aimed at assessing the validity of computational models for seismic behaviour of pile foundations and trying to define better models if necessary. These tests on reduced scale structure, including various types of raft and pile foundations and different kinds of dynamic excitation (harmonic, earthquake simulation, impulsive release of a static force) have been made at the NICE airport site. The present paper deals with the general description of the tests and the first part of interpretation work, limited to in-structure harmonic excitation and earthquake simulation tests analyzed by simple spring -dashpot analytical models. The two following papers (K5-6 and K5-7) are devoted to specialized topics in relation with the interpretation of tests, i-e ground motions analysis for earthquake simulation and research work on a new computational model. Although preliminary conclusions can be drawn from the results obtained so far, further work will be necessary to reach a conclusive assessment on this difficult subject. (orig.)

  11. DETERMINING A SUFFICIENT DEPTH OF PILE FOUNDATION ON THE PERTAMINA GRAVING DOCK DESIGN SORONG PAPUA

    Directory of Open Access Journals (Sweden)

    Franto Novico

    2017-07-01

    Full Text Available Engineering geological aspect and bearing capacity of pile foundation are significant for safety of upper structure, especially for substantial constructions such as a docking ship. Moreover, it provides effectiveness and cost efficiency when applies in rural areas of Indonesia. This is due to lack of docking ship appropriately built at rural areas particularly in eastern areas of Indonesia. Karim island of Papua even though is a small island yet is very strategic as Pertamina place its transitory function on that island connecting its oil supply route to Sorong. Appropriate docking ship construction is required to aim the effective and efficient port management. Choosing the most suitable structure for a docking is also the key. Graving dock structure has been chosen by Pertamina as the most appropriate type of structure for the docking ship in Karim Island. The structure of graving dock planned to be built in Karim island Papua, is projected to be able to serve the maximum 7500 DWT ship capacity, with approximately dimension is 125 x 25 x 8 meters. Therefore, to support the plan, type and design of the best foundation is the key. There are two methods could be done in determining the type and bearing capacity foundation. Field and laboratory test applied ASTM, field observation result by applying Meyerhoff theory and laboratorial analysis derived from Tarzaghi theory. Those observation and analysis has confirmed that the soil layer at the graving dock design consists of three layers, those are; cover layer, silt-clay layer and clay rock unit. Therefore, the most suitable foundation to be constructed in that area is a pile massive foundation, with depth of pile foundation approximately -20 m below the land surface, and the ultimate point load pile massive for 30x30 cm - 75x75 cm dimension approximately 79.76 – 406.25 ton, and frictional resistance value approximately 24.59-61.48 ton.

  12. 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

  13. 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...... 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...

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

    DEFF Research Database (Denmark)

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

    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...

  15. 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

    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......, 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....

  16. 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.

  17. The Effects of Time on Soil Behaviour and Pile Capacity

    DEFF Research Database (Denmark)

    Augustesen, Anders

    When designing pile foundations, static design equations, pile driving formulae, static loading tests or stress wave analyses can be employed to estimate the axial capacity of single piles. Both laboratory and field tests show that soil exhibits time-dependent behaviour. An important result...... is that soil gains additional strength and stiffness with time due to time-dependent processes such as ageing. Similarly, results show that the capacity of piles increases, to a certain extent, with time after installation due to time-dependent processes in the soil. However, most design methods do not take...... 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...

  18. Starting up a programme of atomic piles using compressed gas

    International Nuclear Information System (INIS)

    Horowitz, J.; Yvon, J.

    1959-01-01

    1) An examination of the intellectual and material resources which have directed the French programme towards: a) the natural uranium and plutonium system, b) the use of compressed gas as heat transfer fluid (primary fluid). 2) The parts played in exploring the field by the pile EL2 and G1, EL2 a natural uranium, heavy water and compressed gas pile, G1 a natural uranium, graphite and atmospheric air pile. 3) Development of the neutronics of graphite piles: physical study of G1. 4) The examination of certain problem posed by centres equipped with natural uranium, graphite and compressed carbon dioxide piles: structure, special materials, fluid circuits, maximum efficiency. Economic aspects. 5) Aids to progress: a) piles for testing materials and for tests on canned fuel elements, b) laboratory and calculation facilities. 6) Possible new orientations of compressed gas piles: a) raising of the pressure, b) enriched fuel, c) higher temperatures, d) use of heavy water. (author) [fr

  19. Model tests on single piles in soft clay

    Energy Technology Data Exchange (ETDEWEB)

    Pan, J.L. [Durham Univ., Durham, (United Kingdom). School of Engineering; Goh, A.T.C.; Wong, K.S.; Teh, C.I. [Nanyang Technological Univ., (Singapore). Geotechnical Research Centre

    2000-08-04

    The behaviour of single stainless steel piles subjected to lateral soft clay soil movement was investigated in laboratory model tests in an effort to determine the ultimate soil pressure acting along the pile shaft. A custom designed apparatus was manufactured and calibrated for the test which measured the limiting soil pressures acting along the model pile shaft. The ultimate soil pressure was determined based on the maximum value of this measurement. The results show that the ultimate soil pressure for single passive piles was about 10 times the undrained shear strength, and the magnitude of the soil translation needed to fully mobilize the ultimate soil pressure on the single passive piles was about half the pile width. Further experimental study is needed to examine the effects of the pile end fixity, flexibility and shape and to confirm the effects of sample size and the disturbance due to soil sample preparation. 17 refs., 10 figs.

  20. 3D FEM Analysis of a Pile-Supported Riverine Platform under Environmental Loads Incorporating Soil-Pile Interaction

    Directory of Open Access Journals (Sweden)

    Denise-Penelope N. Kontoni

    2018-01-01

    Full Text Available An existing riverine platform in Egypt, together with its pile group foundation, is analyzed under environmental loads using 3D FEM structural analysis software incorporating soil-pile interaction. The interaction between the transfer plate and the piles supporting the platform is investigated. Two connection conditions were studied assuming fixed or hinged connection between the piles and the reinforced concrete platform for the purpose of comparison of the structural behavior. The analysis showed that the fixed or hinged connection condition between the piles and the platform altered the values and distribution of displacements, normal force, bending moments, and shear forces along the length of each pile. The distribution of piles in the pile group affects the stress distribution on both the soil and platform. The piles were found to suffer from displacement failure rather than force failure. Moreover, the resulting bending stresses on the reinforced concrete plate in the case of a fixed connection between the piles and the platform were almost doubled and much higher than the allowable reinforced concrete stress and even exceeded the ultimate design strength and thus the environmental loads acting on a pile-supported riverine offshore platform may cause collapse if they are not properly considered in the structural analysis and design.

  1. Horizontal vibrations of piles in a centrifuge

    International Nuclear Information System (INIS)

    Bourdin, B.

    1987-01-01

    The aim of the thesis is the study of soil dynamics for important structures like nuclear power plants, offshore platforms, dams etc. Experimental results of horizontal vibrations on a pile partially anchored in a soil scale model put into a centrifuge are presented. Mechanical similitude conditions from equilibrium equations or rheologic laws are described. After a description of testing equipment (centrifuge, electrodynamic excitator) experimental results are interpreted with a model. Non-linearities on frequency response curves are characterized [fr

  2. Uplift Capacity of Inclined Underreamed Piles Subjected to Vertical Load

    Science.gov (United States)

    Rahman, Md. Akilur; Sengupta, Siddhartha

    2017-12-01

    Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Inclined (batter) piles are used to support such structures, and to carry the horizontal and vertical loads resulted from the overturning moments. Though studies have been done with inclined piles having no underream bulb, little information is available in the literature about estimating the uplift capacity of inclined underreamed piles. In the present study laboratory experiments have been done with vertically loaded model piles having no underream as well as with one and two underreams. The piles were positioned at angle of inclination of θ = 0°, 10°, 20°, 30° (with vertical); and placed in locally available sand under vertical uplift load. Three different pile stem diameters (D = 20, 25, and 35 mm) were used. The corresponding pile length to stem diameter (l/D) ratio were 18, 14, and 10 respectively. Experiments had been conducted with two relative different densities (45 and 70%) of sand. The failure uplift loads were obtained in each case. It had been found that for inclined piles increase in number of underream bulbs from 0 to 2 was quite effective in resisting uplift loads corresponding to piles having l/D equals to 10. The percentage decreases in uplift capacity corresponding to increase in inclination angle were more pronounced for piles with double underreams.

  3. Integrity Testing of Pile Cover Using Distributed Fibre Optic Sensing

    Directory of Open Access Journals (Sweden)

    Yi Rui

    2017-12-01

    Full Text Available The integrity of cast-in-place foundation piles is a major concern in geotechnical engineering. In this study, distributed fibre optic sensing (DFOS cables, embedded in a pile during concreting, are used to measure the changes in concrete curing temperature profile to infer concrete cover thickness through modelling of heat transfer processes within the concrete and adjacent ground. A field trial was conducted at a high-rise building construction site in London during the construction of a 51 m long test pile. DFOS cables were attached to the reinforcement cage of the pile at four different axial directions to obtain distributed temperature change data along the pile. The monitoring data shows a clear development of concrete hydration temperature with time and the pattern of the change varies due to small changes in concrete cover. A one-dimensional axisymmetric heat transfer finite element (FE model is used to estimate the pile geometry with depth by back analysing the DFOS data. The results show that the estimated pile diameter varies with depth in the range between 1.40 and 1.56 m for this instrumented pile. This average pile diameter profile compares well to that obtained with the standard Thermal Integrity Profiling (TIP method. A parametric study is conducted to examine the sensitivity of concrete and soil thermal properties on estimating the pile geometry.

  4. Interesting Developments in Testing Methods Applied to Foundation Piles

    Science.gov (United States)

    Sobala, Dariusz; Tkaczyński, Grzegorz

    2017-10-01

    Both: piling technologies and pile testing methods are a subject of current development. New technologies, providing larger diameters or using in-situ materials, are very demanding in terms of providing proper quality of execution of works. That concerns the material quality and continuity which define the integral strength of pile. On the other side we have the capacity of the ground around the pile and its ability to carry the loads transferred by shaft and pile base. Inhomogeneous nature of soils and a relatively small amount of tested piles imposes very good understanding of small amount of results. In some special cases the capacity test itself form an important cost in the piling contract. This work presents a brief description of selected testing methods and authors remarks based on cooperation with Universities constantly developing new ideas. Paper presents some experience based remarks on integrity testing by means of low energy impact (low strain) and introduces selected (Polish) developments in the field of closed-end pipe piles testing based on bi-directional loading, similar to Osterberg idea, but without sacrificial hydraulic jack. Such test is suitable especially when steel piles are used for temporary support in the rivers, where constructing of conventional testing appliance with anchor piles or kentledge meets technical problems. According to the author’s experience, such tests were not yet used on the building site but they bring a real potential especially, when the displacement control can be provided from the river bank using surveying techniques.

  5. Review of vibration effect during piling installation to adjacent structure

    Science.gov (United States)

    Rahman, Nurul Aishah Abd; Musir, Adhilla Ainun; Dahalan, Nurol Huda; Ghani, Abdul Naser Abdul; Khalil, Muhamad Kasimi Abd

    2017-12-01

    Basically, many major structures across the world such as towers, high rise building, houses and bridges utilize pile as a support material. The use of pile is important to strengthen the structures. However, this has led to another problem to the nearest surrounding structures resulted from pile driving. As part of a construction work, unavoidable pile driving activity generates a vibration towards the surrounding structures if uncontrolled may cause damage to the adjacent structure. As the current construction works are frequently located in urban areas where the distance between the nearest building structures is not far, vibration may cause damage to nearby structures. Knowing which part of the building that is mostly affected by various vibration patterns from the impact of pile driving is crucial. Thus, it is very important to predict the impact of vibration during piling installation work. This paper reviews the vibrations generated by piling activity toward surrounding structures in terms sources of vibration, impact of piling installation, pile-soil interaction, and factors affecting the vibration impact of building as well as to study the parameters involved in vibration generation during piling works.

  6. Integrity Testing of Pile Cover Using Distributed Fibre Optic Sensing

    Science.gov (United States)

    Rui, Yi; Kechavarzi, Cedric; O’Leary, Frank; Barker, Chris; Nicholson, Duncan; Soga, Kenichi

    2017-01-01

    The integrity of cast-in-place foundation piles is a major concern in geotechnical engineering. In this study, distributed fibre optic sensing (DFOS) cables, embedded in a pile during concreting, are used to measure the changes in concrete curing temperature profile to infer concrete cover thickness through modelling of heat transfer processes within the concrete and adjacent ground. A field trial was conducted at a high-rise building construction site in London during the construction of a 51 m long test pile. DFOS cables were attached to the reinforcement cage of the pile at four different axial directions to obtain distributed temperature change data along the pile. The monitoring data shows a clear development of concrete hydration temperature with time and the pattern of the change varies due to small changes in concrete cover. A one-dimensional axisymmetric heat transfer finite element (FE) model is used to estimate the pile geometry with depth by back analysing the DFOS data. The results show that the estimated pile diameter varies with depth in the range between 1.40 and 1.56 m for this instrumented pile. This average pile diameter profile compares well to that obtained with the standard Thermal Integrity Profiling (TIP) method. A parametric study is conducted to examine the sensitivity of concrete and soil thermal properties on estimating the pile geometry. PMID:29257094

  7. Geomorphic reclmation of a coal refuse pile

    Science.gov (United States)

    Hopkinson, L. C.; Quaranta, J.

    2017-12-01

    Geomorphic reclamation is a technique that may offer opportunities to improve mine reclamation in Central Appalachia. The design approach is based on constructing a steady-state, mature landform condition and takes into account the long-term climatic conditions, soil types, terrain grade, and vegetation. Geomorphic reclamation has been applied successfully in semi-arid regions but has not yet been applied in Central Appalachia. This work describes a demonstration study where geomorphic landforming techniques are being applied to a coarse coal refuse pile in southern West Virginia, USA. The reclamation design includes four geomorphic watersheds that radially drain runoff from the pile. Each watershed has one central draining channel and incorporates compound slope profiles similarly to naturally eroded slopes. Planar slopes were also included to maintain the impacted area. The intent is to alter the hydrology to decrease water quality treatment costs. The excavation cut and fill volumes are comparable to those of more conventional refuse pile reclamation designs. If proven successful then this technique can be part of a cost-effective solution to improve water quality at active and future refuse facilities, abandoned mine lands, bond forfeiture sites, landfills, and major earthmoving activities within the region.

  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. Impedance function of a group of vertical piles

    International Nuclear Information System (INIS)

    Wolf, J.P.; Arx, G.A. von

    1978-01-01

    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)

  10. The reactor Cabri; La pile cabri

    Energy Technology Data Exchange (ETDEWEB)

    Ailloud, J.; Millot, J.P. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1964-07-01

    exceptional circumstances... - experimental investigations on power excursions linked with precise initial conditions: the aim of this work is to define the basis for theoretical research, and the limits beyond which the risks of explosion cease to be negligible. The research work will be done so as to enable checking with outside reactor experiments and to continue them in the explosion field. - studies of the behaviour of the reactor control-instrumentation. - experimental investigations related with transient operation with initial short life (study of boiling, temperature measurements, vacuum pressure and fraction...) with the aim of defining the hypotheses of a theory on swimming-pool reactor kinetics related to heat transfer phenomena, - investigations of the behaviour of fuels in reactors (these experiments are planned to be carried out in loops) Preliminary experimental results. CABRI went critical on the 21 December 1963. The first transient experiments are expected for March 1964. (authors) [French] II devenait necessaire de construire en France une pile qui permette d'etudier les conditions de fonctionnement des installations futures, de choisir, tester et mettre au point les dispositifs de securite a adopter. On a choisi une pile a eau, type de pile qui correspond aux constructions les plus nouvelles du CEA en matiere de piles laboratoire ou d'universite; il importe en effet de pouvoir evaluer les risques presentes et d'etudier les possibilites d'augmentation de puissance constamment demandees par les utilisateurs: il est particulierement interessant d'eclaircir les phenomenes d'oscillation de puissance et les risques de calefaction (burn out). Les programmes de travaux sur CABRI seront harmonises avec les travaux effectues sur les Spert americains de meme type; lors de sa construction des contacts fructueux ont ete etablis avec les specialistes americains qui ont defini les premiers de ces reacteurs. La communication donne une

  11. Hydrodynamic bearings

    CERN Document Server

    Bonneau, Dominique; Souchet, Dominique

    2014-01-01

    This Series provides the necessary elements to the development and validation of numerical prediction models for hydrodynamic bearings. This book describes the rheological models and the equations of lubrication. It also presents the numerical approaches used to solve the above equations by finite differences, finite volumes and finite elements methods.

  12. Contiguous Pile Wall as a Deep Excavation Supporting System

    OpenAIRE

    Venkata Ramasubbarao GODAVARTHI; Dineshbabu MALLAVALLI; Ramya PEDDI; Neelesh KATRAGADDA; Prudhvikrishna MULPURU

    2012-01-01

    Providing space for parking, public amenities, etc in multi-storey buildings at town centres has created a need to go deep excavations into ground. Deep excavations are supported by systems like conventional retaining walls, sheet pile walls, braced walls, diaphragm walls and pile walls. This article describes various excavation supporting systems that are in vogue essentially contiguous pile wall and its advantages. A detailed design methodology of an excavation supporting system is furnishe...

  13. Numerical Study on Soil Arching Effects of Stabilizing Piles

    OpenAIRE

    Fan, Fusong; Chen, Guangqi; Hu, Xinli; Wang, Wei

    2015-01-01

    The Soil arching effect, the transfer of soil pressure from the yielding soil to the piles support, is a phenomena commonly encountered in geotechnical engineering for stabilizing landslides. In this paper, the (finite element method) FEM and (discontinuous deformation analysis) DDA were used to study on the soil arching effects of stabilizing piles in landslides. This paper proposes a method for two dimensional numerical simulation to perform three dimensional soil-pile interaction so that t...

  14. Contiguous Pile Wall as a Deep Excavation Supporting System

    Directory of Open Access Journals (Sweden)

    Venkata Ramasubbarao GODAVARTHI

    2012-08-01

    Full Text Available Providing space for parking, public amenities, etc in multi-storey buildings at town centres has created a need to go deep excavations into ground. Deep excavations are supported by systems like conventional retaining walls, sheet pile walls, braced walls, diaphragm walls and pile walls. This article describes various excavation supporting systems that are in vogue essentially contiguous pile wall and its advantages. A detailed design methodology of an excavation supporting system is furnished in this study. A case study on the Contiguous pile wall retaining system for supporting a deep excavation at a town centre is presented.

  15. Critical sizes and flux distributions in the shut down pile

    International Nuclear Information System (INIS)

    Banchereau, A.; Berthier, P.; Genthon, J.P.; Gourdon, C.; Lattes, R.; Martelly, J.; Mazancourt, R. de; Portes, L.; Sagot, M.; Schmitt, A.P.; Tanguy, P.; Teste du Bailler, A.; Veyssiere, A.

    1957-01-01

    An important part of the experiments carried out on the reactor G1 during a period of shut-down has consisted in determinations of critical sizes, and measurements of flux distribution by irradiations of detectors. This report deals with the following points: 1- Critical sizes of the flat pile, the long pile and the uranium-thorium pile. 2- Flux charts of the same piles, and study of an exponential experiment. 3- Determination of the slit effect. 4- Calculation of the anisotropy of the lattice. 5- Description of the experimental apparatus of the irradiation measurements. (author) [fr

  16. Natural radioactivity at CBPP waste pile

    International Nuclear Information System (INIS)

    Kovac, Jadranka; Marovic, Gordana

    2008-01-01

    Electrical power requirements will necessitate doubling the present generating capacity in Croatia in the future. As a result, environmental discharges associated with the coal power industry will considerably increase. Burning of coal is one source of enhanced radiation exposure to naturally occurring elements, particularly members of uranium and thorium decay chains. By coal burning (in CBPP at about 1700 C degrees) the activity originating from uranium and thorium is redistributed from underground (where the impact on humanity is nil) and liberated into the environment. Most of the radioactive substances are concentrated in the ash and slag, which are heavy and drop to the bottom of a furnace, lately transported to deposit pile, from where some activity may leach into aquifer, or be dispersed by wind. Lighter fly ash, however, is carried up the chimney and into the atmosphere and irradiates people and contaminates food crops. Also, 222 Rn escapes into the atmosphere during incineration, while the non-gaseous members of the uranium decay series remain in the ash and slag. Extensive investigations have been performed in the coal burning power plant (CBPP) Plomin in Croatia and at deposit pile. A network of radon escalation measurements, in-situ gamma-spectrometric measurements and monitoring of waste pile were organized. The results of the measurements confirm that the ash/slag deposite site are well monitored and involve all the necessary protective measures. All obtained data can be used as a valuable database for future estimations and modeling of the impact of radioactive pollution to the marine environment. (author)

  17. 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 (eyewitness of a crater formed by a stony meteorite; (b) undetected thermal 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

  18. Environmentally Friendly Solution to Ground Hazards in Design of Bridges in Earthquake Prone Areas Using Timber Piles

    Science.gov (United States)

    Sadeghi, H.

    2015-12-01

    Bridges are major elements of infrastructure in all societies. Their safety and continued serviceability guaranties the transportation and emergency access in urban and rural areas. However, these important structures are subject to earthquake induced damages in structure and foundations. The basic approach to the proper support of foundations are a) distribution of imposed loads to foundation in a way they can resist those loads without excessive settlement and failure; b) modification of foundation ground with various available methods; and c) combination of "a" and "b". The engineers has to face the task of designing the foundations meeting all safely and serviceability criteria but sometimes when there are numerous environmental and financial constrains, the use of some traditional methods become inevitable. This paper explains the application of timber piles to improve ground resistance to liquefaction and to secure the abutments of short to medium length bridges in an earthquake/liquefaction prone area in Bohol Island, Philippines. The limitations of using the common ground improvement methods (i.e., injection, dynamic compaction) because of either environmental or financial concerns along with the abundance of timber in the area made the engineers to use a network of timber piles behind the backwalls of the bridge abutments. The suggested timber pile network is simulated by numerical methods and its safety is examined. The results show that the compaction caused by driving of the piles and bearing capacity provided by timbers reduce the settlement and lateral movements due to service and earthquake induced loads.

  19. Visual in-pile fuel disruption experiments

    International Nuclear Information System (INIS)

    Cano, G.L.; Ostensen, R.W.; Young, M.F.

    1978-01-01

    In a loss-of-flow (LOF) accident in an LMFBR, the mode of disruption of fuel may determine the probability of a subsequent energetic excursion. To investigate these phenomena, in-pile disruption of fission-heated irradiated fuel pellets was recorded by high speed cinematography. Instead of fuel frothing or dust-cloud breakup (as used in the SAS code) massive and very rapid fuel swelling, not predicted by analytical models, occurred. These tests support massive fuel swelling as the initial mode of fuel disruption in a LOF accident. (author)

  20. Bearing structures

    International Nuclear Information System (INIS)

    Lee, A.S.; Preece, G.E.

    1988-01-01

    A hydrostatic bearing for the lower end of the vertical shaft of a sodium pump comprises a support shell encircling the shaft and a bush located between the shell and shaft. Liquid sodium is fed from the pump outlet to the bush/shaft and bush/shell interfaces to provide hydrostatic support. The bush outer surface and the shell inner surface are of complementary part-spherical shape and the bush floats relative to the shaft so that the bush can align itself with the shaft axis. Monitoring of the relative rotational speed of the bush with respect to the shaft (such rotation being induced by the viscous drag forces present) is also performed for the purposes of detecting abnormal operation of the bearing or partial seizure, at least one magnet is rotatable with the bush, and a magnetic sensor provides an output having a frequency related to the speed of the bush. (author)

  1. Camshaft bearing arrangement

    Energy Technology Data Exchange (ETDEWEB)

    Aoi, K.; Ozawa, T.

    1986-06-10

    A bearing arrangement is described for the camshaft of an internal combustion engine or the like which camshaft is formed along its length in axial order with a first bearing surface, a first cam lobe, a second bearing surface, a second cam lobe, a third bearing surface, a third cam lobe and a fourth bearing surface, the improvement comprising first bearing means extending around substantially the full circumference of the first bearing surface and journaling the first bearing surface, second bearing means extending around substantially less than the circumference of the second bearing surface and journaling the second bearing surface, third bearing means extending around substantially less than the circumference of the third bearing surface and journaling the third bearing surface, and fourth bearing means extending around substantially the full circumference of the fourth bearing surface and journaling the first bearing surface.

  2. Lateral resistance of piles near vertical MSE abutment walls.

    Science.gov (United States)

    2013-03-01

    Full scale lateral load tests were performed on eight piles located at various distances behind MSE walls. The objective of the testing was to determine the effect of spacing from the wall on the lateral resistance of the piles and on the force induc...

  3. Piling up technology of goods irradiated by single plate source

    International Nuclear Information System (INIS)

    Xia Hezhou; Chen Yuxia; Cao Hongyun; Lin Yong; Zhou guoquan

    1999-01-01

    In the irradiation process of piling up goods in static state, four irradiation working sites and single plate source was adopted. The results showed that piling up in this way remarkably raised the irradiation quality of goods. The utilization rate of radioactive ray reached 22.27%

  4. Visualization of soil arching in flexible piled embankments

    Indian Academy of Sciences (India)

    Abstract. Piled embankments rely on soil arching, but, when geogrid reinforce- ments 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 ...

  5. Visualization of soil arching in flexible piled embankments

    Indian Academy of Sciences (India)

    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 ...

  6. 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.

  7. Visualization of soil arching in flexible piled embankments

    Indian Academy of Sciences (India)

    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 ...

  8. Effect of piles on the seismic response of mosques minarets

    Directory of Open Access Journals (Sweden)

    Mohamed Ahmed Abdel-Motaal

    2014-03-01

    Minaret (60.0-m height was studied to investigate the effects of soil stiffness, pile length, diameter, and arrangement, on the minaret and pile dynamic behavior. Comparison between study results and conventional analysis method is illustrated. Study results, discussion, and conclusion are given.

  9. Alteration and arenization processes of granitic waste rock piles from former uranium Mines in Limousin, France.

    Science.gov (United States)

    Kanzari, Aisha; Boekhout, Flora; Gérard, Martine; Galoisy, Laurence; Phrommavanh, Vannapha; Descostes, Michael

    2014-05-01

    France counts approximately 200 former uranium mines, 50 of which are located in the Limousin region. Mining activities between 1945 and 2001 have generated close to 200 000 tons of waste rocks in the Limousin, with uranium levels corresponding essentially to the geological background. Waste rock piles from three former mining sites in this region, were selected according to their age, uranium content and petrological signature. These sites are part of the two-mica granitic complex of St Sylvestre massif, formed 324 million years ago. Granitic blocks that build up the waste rock piles have experienced different processes and intensities of alteration before their emplacement at the surface. These processes are responsible for the petrological heterogeneity throughout the waste rock pile at the time of construction. It is important to make a distinction within waste rocks between natural-cut-off waste rocks and economic-cut-off waste rocks. The latter represents a minority and is linked to stock prices. Natural-cut-off waste rocks contain about 20 ppm of uranium; economic-cut-off waste rocks contain about 100 to 300 ppm of uranium. The aims of this study are to 1) assess the neo-formation of U-bearing minerals hosted by these rocks, and 2) to characterize the weathering processes since the construction of the rock piles, including both mechanical and chemical processes. The structure of the waste rocks piles, from metric blocks to boulders of tens centimeters, induces an enhanced weathering rate, compared to a granitic massif. Mechanical fracturing and chemical leaching by rainwater (arenization) of the waste rocks produce a sandy-silty alteration phase. Silty-clay weathering aureoles of submetric-granitic blocks evolving into technic soil are mainly located below growing birch trees. Sampling on the rock piles was restricted to surface rocks. Samples collected consist mainly of granites, and rare lamprophyres with a high radiometric signal, thereby especially

  10. 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.

  11. Optimal Design of Sheet Pile Wall Embedded in Clay

    Science.gov (United States)

    Das, Manas Ranjan; Das, Sarat Kumar

    2015-09-01

    Sheet pile wall is a type of flexible earth retaining structure used in waterfront offshore structures, river protection work and temporary supports in foundations and excavations. Economy is an essential part of a good engineering design and needs to be considered explicitly in obtaining an optimum section. By considering appropriate embedment depth and sheet pile section it may be possible to achieve better economy. This paper describes optimum design of both cantilever and anchored sheet pile wall penetrating clay using a simple optimization tool Microsoft Excel ® Solver. The detail methodology and its application with examples are presented for cantilever and anchored sheet piles. The effects of soil properties, depth of penetration and variation of ground water table on the optimum design are also discussed. Such a study will help professional while designing the sheet pile wall penetrating clay.

  12. The influence of connecting pile cap-column in the mechanisms of break in the two pile caps

    Directory of Open Access Journals (Sweden)

    A. C. MESQUITA

    Full Text Available Abstract The paper analyzes the two pile caps with partially embedded socket and subject a center load. Three models were experimentally tested, varying the type of conformation of the column and walls of the socket, with a smooth, the other rough, and a monolithic two pile cap, used for reference. The roughening of the column-socket interface was examined with the aim of verifying the difference of the distribution of compressive and tensile stresses in the strut an tie model used for design. The experimental test to show that the two pile caps with conformation rough of the column and walls of the socket, support more load in comparison with two pile caps with smooth of the column and walls of the socket. Both however underperformed the monolithic two pile cap, with values of 66% and 36% respectively.

  13. Digitalisation in atomic pile control (1962)

    International Nuclear Information System (INIS)

    Furet, J.

    1962-01-01

    A brief survey is first given of the general theorems of Boodle's algebra and of sequence systems using D.A. Huffmans theory. Some indications are then given concerning the setting-up and the operation of digital computers and also of the principal codes used in digital techniques. It is then shown how digitalisation in atomic pile control makes it possible to use new techniques having the following advantages in particular: greater working safety, a higher degree of centralisation, and suppression of the linear elements. A few examples are given of the application of these techniques to control, particularly with respect to the measurement of the neutronic power and of the period and also of course, to the treatment of the data and the sequence automatisms. The advantage of using digital techniques in the shutdown channels is also examined. Finally a review is given of the technology and the viability of the control devices used. (author) [fr

  14. Evaluation of end bearing capacity of drilled shafts in sand by ...

    African Journals Online (AJOL)

    Drilled shafts are a common type of pile foundations which are often used as foundations for buildings, bridges and other structures. The end bearing capacity of drilled shafts, which plays an important role in their design particularly in sandy soils, has traditionally been estimated using empirical or semi-empirical methods.

  15. The Metal Hoard from Pile in Scania, Sweden

    DEFF Research Database (Denmark)

    Vandkilde, Helle

    The metal hoard from Pile has branded the onset of the rich Nordic Bronze Age since its discovery in 1864 at the coast of Scania in southwestern Sweden. Yet, this book provides the first detailed documentation, scientific examination and historical interpretation. Indeed, Pile emerges as the earl......The metal hoard from Pile has branded the onset of the rich Nordic Bronze Age since its discovery in 1864 at the coast of Scania in southwestern Sweden. Yet, this book provides the first detailed documentation, scientific examination and historical interpretation. Indeed, Pile emerges...... as the earliest, finest and among the largest of the Nordic sacrificial deposits of metalwork in watery settings. In this book, Pile figures as a place at the brim of the sea as much as an ensemble of exquisite things and coppers that arrived to Scandinavia from various parts of Europe around 2000 BCE. Pile...... was a maritime node and a landing place for exogenous metals and exotic daggers and rings, but also a site where the smith produced coveted axes for wider distribution locally and regionally. Such robust axes of ‘Pile-type’ boosted the political economy of Southern Scandinavia 2100-1700 BCE while adding to a hot...

  16. 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.

  17. Field Test of Driven Pile Group under Lateral Loading

    Science.gov (United States)

    Gorska, Karolina; Rybak, Jaroslaw; Wyjadlowski, Marek

    2017-12-01

    All the geotechnical works need to be tested because the diversity of soil parameters is much higher than in other fields of construction. Horizontal load tests are necessary to determine the lateral capacity of driven piles subject to lateral load. Various load tests were carried out altogether on the test field in Kutno (Poland). While selecting the piles for load tests, different load combinations were taken into account. The piles with diverse length were chosen, on the basis of the previous tests of their length and integrity. The subsoil around the piles consisted of mineral soils: clays and medium compacted sands with the density index ID>0.50. The pile heads were free. The points of support of the “base” to which the dial gauges (displacement sensors) were fastened were located at the distance of 0.7 m from the side surface of the pile loaded laterally. In order to assure the independence of measurement, additional control (verifying) geodetic survey of the displacement of the piles subject to the load tests was carried out (by means of the alignment method). The trial load was imposed in stages by means of a hydraulic jack. The oil pressure in the actuator was corrected by means of a manual pump in order to ensure the constant value of the load in the on-going process of the displacement of the pile under test. On the basis of the obtained results it is possible to verify the numerical simulations of the behaviour of piles loaded by a lateral force.

  18. Three-dimensional analysis of two-pile caps

    Directory of Open Access Journals (Sweden)

    T.E.T. Buttignol

    Full Text Available This paper compares the results between a non-linear three-dimensional numerical analysis of pile caps with two piles and the experimental study conducted by Delalibera. It is verified the load-carrying capacity, the crack pattern distribution, the principal stress in concrete and steel, the deflection and the fracture of the pile cap. The numerical analysis is executed with the finite-element software ATENA 3D, considering a perfect bond between concrete and steel. The numerical and experimental results are presented and have demonstrated a good approximation, reasserting the results of the experimental model and corroborating the theory.

  19. Elementary calculation of the shutdown delay of a pile

    International Nuclear Information System (INIS)

    Yvon, J.

    1949-04-01

    This study analyzes theoretically the progress of the shutdown of a nuclear pile (reactor) when a cadmium rod is introduced instantaneously. For simplification reasons, the environment of the pile is considered as homogenous and only thermal neutrons are considered (delayed neutrons are neglected). Calculation is made first for a plane configuration (plane vessel, plane multiplier without reflector, and plane multiplier with reflector), and then for a cylindrical configuration (multiplier without reflector, multiplier with infinitely thick reflector, finite cylindrical piles without reflector and with reflector). The self-sustain conditions are calculated for each case and the multiplication length and the shutdown delay are deduced. (J.S.)

  20. Monitoring moisture content, temperature, and humidity in whole-tree pine chip piles

    Science.gov (United States)

    John Klepac; Dana Mitchell; Jason Thompson

    2015-01-01

    Two whole-tree chip piles were monitored for moisture content, temperature, and relative humidity from October 8th, 2010 to March 16th, 2011 at a location in south Alabama. Initial moisture content samples were collected immediately after chips were delivered to the study location on October 8th for Pile 1 and October 22nd for Pile 2. During pile construction, Lascar...

  1. Estimating volume, biomass, and potential emissions of hand-piled fuels

    Science.gov (United States)

    Clinton S. Wright; Cameron S. Balog; Jeffrey W. Kelly

    2009-01-01

    Dimensions, volume, and biomass were measured for 121 hand-constructed piles composed primarily of coniferous (n = 63) and shrub/hardwood (n = 58) material at sites in Washington and California. Equations using pile dimensions, shape, and type allow users to accurately estimate the biomass of hand piles. Equations for estimating true pile volume from simple geometric...

  2. A Simple Algorithm for Analyzing a Piled Raft by Considering Stress Distribution

    Directory of Open Access Journals (Sweden)

    Alireza Saeedi Azizkandi

    2014-12-01

    Full Text Available Numerous techniques have been presented by different researchers to analyze piled raft. In order to analyze pile foundation, soil can be modeled as spring, continuous medium, or porous media. Pile can also be modeled as spring or continuous medium. This study includes three main stages: a short description of different types of analysis methods of pile foundation, writing a computer program based on the finite element method (FEM for analyzing piled raft foundation (in this program, foundation is modeled as a flexible plate, soil and pile are modeled by Winkler springs, and comparison of different concepts of pile group design.

  3. 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.

  4. 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.

  5. 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.

  6. 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....

  7. Assessment of Soil Arching Factor for Retaining Wall Pile Foundations

    Science.gov (United States)

    2017-03-31

    Despite the prevalence of the soldier piles retaining wall systems as temporary and even permanent shoring systems along state highways, relatively little is known on the effect of the foreslope bench width and the slope inclination on the arching ca...

  8. Field testing of jet-grouted pile : [summary].

    Science.gov (United States)

    2014-01-01

    In many areas of Florida, local geology dictates the use of deep foundations for transportation structures bridges, noise walls, signage, etc. When concrete piles are used, they are either prestressed at the casting yard, cast in situ through a h...

  9. Update LADOTD policy on pile driving vibration management.

    Science.gov (United States)

    2012-02-01

    The main objective of this project was to update the current Louisiana Department of Transportation and Development (LADOTD) policy on pile driving vibration risk management with a focus on how to determine an appropriate vibration monitoring area. T...

  10. New Mathematical Modelling of Stabilizing Pile with Prestressed Tieback Anchors

    Directory of Open Access Journals (Sweden)

    Cheng Huang

    2013-01-01

    Full Text Available This paper presents a novel mathematical modelling for analyzing stabilizing piles with prestressed tieback anchors. The new differential equations governing the mechanical response of the stabilizing pile are formulated and the boundary conditions considering the tie-back anchors are mathematically specified. Then, the system of differential equations is numerically solved by the high-accuracy Runge-Kutta finite difference method. A simple computer program has been written on the platform of MATLAB to run the procedure of the proposed algorithm. This approach is entirely different from the traditional finite element method used to design the anchored piles. The FEM is employed to verify the feasibility of the developed method. The comparative case study indicates that the proposed method has more higher modeling and computing efficiency than the FEM and can be an alternative method for designing the anchored pile used for slope stabilization.

  11. Influence of cantilevered sheet pile deflection on adjacent roadways.

    Science.gov (United States)

    2009-06-01

    Cantilevered sheet pile walls are often used adjacent roadways as temporary support during construction. Excess movement of these walls has led to excessive roadway distress causing additional repairs to be necessary. This study assessed the effects ...

  12. Performance assessment of deteriorated and retrofitted steel HP piles.

    Science.gov (United States)

    2016-06-01

    Steel piles are known to deteriorate at high rates in Nebraska, partially as a result of exposure to weathering, and partially due to corrosive soils. The Nebraska Department of Roads (NDOR) employs a reinforced concrete jacket to slow the progressio...

  13. 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...

  14. Centrifuge modelling of drained lateral pile - soil response

    DEFF Research Database (Denmark)

    Klinkvort, Rasmus Tofte

    tests were used to investigate the pile - soil interaction to gain a better in-sight into the complex problem. A monotonic test series was carried out initially and then pile - soil interaction curves were deduced from these tests and compared with methodologies used today. The results indicate...... to predict the accumulation of displacement and change in secant stiffness using the observations seen in the centrifuge. With the centrifuge test observation as basis, an cyclic pile - soil interaction element was developed. The element can be used in Winkler type analysis where the soil is modelled...... of rigid piles. The tests have been performed in homogeneously dense dry or saturated Fontainebleau sand in order to mimic simplified drained offshore soil conditions. Approximately half of the tests have been carried out to investigate the centrifuge procedure in order to create a methodology of testing...

  15. 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 (1977...... 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.......Monopile foundations have been used in a large extent to support offshore wind turbines (OWT), being considered as a reliable and cost effective design solution. The accurate estimation of their dynamic response characteristics is essential, since the design of support structures for OWTs has been...

  16. Application of Submerged Grouted Anchors in Sheet Pile Quay Walls

    OpenAIRE

    Mollahasani, Ali

    2014-01-01

    Sheet pile walls are one of the oldest earth retention systems utilized in civil engineering projects. They are used for various purposes; such as excavation support system, cofferdams, cut-off walls under dams, slope stabilization, waterfront structures, and flood walls. Sheet pile walls are one of the most common types of quay walls used in port construction. The worldwide increases in utilization of large ships for transportation have created an urgent need of deepening the seabed within p...

  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. 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.......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....

  19. 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.

  20. Seismological analysis of group pile foundation for reactor

    International Nuclear Information System (INIS)

    Wang Demin.

    1984-01-01

    In the seismic analysis for reactor foundation of nuclear power plant, the local raise of base mat is of great significance. Base on the study of static and dynamic stability as well as soil-structure interaction of group piles on stratified soil, this paper presents a method of seismic analysis for group piles of reactor foundation at abroad, and a case history is enclosed. (Author)

  1. Emissions from prescribed burning of timber slash piles in Oregon

    Science.gov (United States)

    Aurell, Johanna; Gullett, Brian K.; Tabor, Dennis; Yonker, Nick

    2017-02-01

    Emissions from burning piles of post-harvest timber slash (Douglas-fir) in Grande Ronde, Oregon were sampled using an instrument platform lofted into the plume using a tether-controlled aerostat or balloon. Emissions of carbon monoxide, carbon dioxide, methane, particulate matter (PM2.5), black carbon, ultraviolet absorbing PM, elemental/organic carbon, filter-based metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzodioxins/dibenzofurans (PCDD/PCDF), and volatile organic compounds (VOCs) were sampled to determine emission factors, the amount of pollutant formed per amount of biomass burned. The effect on emissions from covering the piles with polyethylene (PE) sheets to prevent fuel wetting versus uncovered piles was also determined. Results showed that the uncovered ("wet") piles burned with lower combustion efficiency and higher emission factors for VOCs, PM2.5, PCDD/PCDF, and PAHs. Removal of the PE prior to ignition, variation of PE size, and changing PE thickness resulted in no statistical distinction between emissions. Results suggest that dry piles, whether covered with PE or not, exhibited statistically significant lower emissions than wet piles due to better combustion efficiency.

  2. Numerical Simulation Study on Lateral Displacement of Pile Foundation and Construction Process under Stacking Loads

    Directory of Open Access Journals (Sweden)

    Yan-yan Cai

    2018-01-01

    Full Text Available Lateral displacement of pile foundation is crucial to the safety of an overall structure. In this study, a numerical simulation on the lateral displacement of pile foundation under stacking loads was conducted to determine its relation with different influencing factors. Simulation results demonstrated that stacking loads at the pile side mostly influence the lateral displacement of pile foundation. The lateral displacement of pile foundation increases by one order of magnitude when the stacking loads increase from 100 kPa to 300 kPa. Other influencing factors are less important than stacking loads. Lateral displacements of the pile body and at the pile top can be reduced effectively by increasing the deformation modulus of surface soil mass, reducing the thickness of soft soil, and expanding pile diameter. Our analysis indicates that a nonlinear relationship exists between the lateral displacement at the pile top and the pile diameter. The lateral resistance of the pile body can be enhanced by coupling the stacking load along piles and the axial force at the pile top. An actual large-scale engineering project was chosen to simulate the effects of postconstructed embankment on lateral displacement and axial force of bridge pile foundation under different construction conditions and to obtain the lateral displacement of the pile body and the negative frictional resistance caused by soft soil compression under stacking loads. On the basis of the calculated results, engineering safety and stability were evaluated, and a guide for the design and construction was proposed.

  3. Corrosion Activity on CFRP-Strengthened RC Piles of High-Pile Wharf in a Simulated Marine Environment

    Directory of Open Access Journals (Sweden)

    Ning Zhuang

    2017-01-01

    Full Text Available We report test results from an experimental study to investigate the effectiveness of carbon fiber-reinforced polymer (CFRP against reinforcing steel bar corrosion. Twelve reinforced-concrete pile specimens of 180 mm square by 1,600 mm long were cast. Three pile specimens were corroded to 5% steel mass loss and then strengthened with CFRP sheets; four specimens were strengthened by using CFRP sheets, whereas the remaining five specimens were not strengthened. The specimens were placed in a simulated marine environment, and corrosion was induced by an impressed current technique. At different theoretical corrosion degrees, nondestructive tests were performed to investigate the corrosion activity of the pile specimens, and destructive tests were performed to determine reinforcing steel bar mass loss. Based on the findings, the effectiveness of the CFRP-strengthened RC piles under aggressive marine environmental conditions was established.

  4. The Supercritical Pile Model for GRBs

    Science.gov (United States)

    Kazanas, Demos

    2006-01-01

    We present the spectral and temporal radiative signatures expected within the Supercritical Pile model of Gamma Ray Bursts (GRB). This model is motivated by the need for a process that provides the dissipation necessary in GRB and presents a well defined scheme for converting the energy stored in the relativistic protons of the Relativistic Blast Waves (RBW) associated with GRB into radiation; at the same time it leads to spectra which exhibit a peak in the burst nuF(sub nu) distribution at an energy E(sub p) approximately equal to 1 MeV in the observer s frame, in agreement with observation and largely independent of the Lorentz factor GAMMA of the associated relativistic outflow. Furthermore, this scheme does not require (but does not preclude) acceleration of particles at the shock other than that provided by the isotropization of the flow bulk kinetic energy on the RBW frame. In the present paper we model in detail the evolution of protons, electrons and photons from a RBW to produce detailed spectra of the prompt GRB phase as a function of time from across a very broad range spanning roughly 4 log10 GAMMA decades in frequency. The model spectra are in general agreement with observations and provide a means for the delineating of the model parameters through direct comparison with trends observed in GRB properties.

  5. 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)

    Lehtikangas, P.; Lundkvist, H.

    1991-01-01

    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

  6. 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.

  7. 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.

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

    Directory of Open Access Journals (Sweden)

    Priyanka Kumari

    2016-04-01

    Full Text Available 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.

  9. 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.

  10. 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

    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......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 the surrounding soil implies upward shear stresses at the soil–pile interface leading to tensile vertical stresses in the pile. In the current case, they exceed the tensile strength of concrete. The tensile vertical stresses peak after 35-50 years. However, the heave of the soil continues for additional 300 years...

  11. Investigation of a North Sea oil platform drill cuttings pile

    International Nuclear Information System (INIS)

    Hartley, J.P.; Watson, T.N.

    1993-01-01

    A comprehensive study of the drill cuttings pile at North West Hutton was undertaken in August, 1992. Fifty one wells have been drilled in the field, mainly using mineral oil based drill fluids, with the cuttings discharged to sea. The cuttings pile was mapped using a 3D side scan sonar system and the periphery was defined by towed side scan sonar and gamma ray spectrometer surveys. The pile was cored by vibrocorer to a maximum depth of 2.35m. The cores were assessed geotechnically and subsampled for physical and chemical analyses. Environmental impact was investigated by grab sampling at 12 stations out to 7,500m, selected on the basis of cuttings distribution. The results are relevant to the corrosion and long-term environmental effects of oily cuttings piles, the remove/leave alone debate, and abandonment planning. The cores were subsampled for hydrocarbon, trace metals and sulphide content and grain size analysis. Metals analyses included identification of metal species to estimate bioavailability and implications of pile disturbance. Estimates of oil migration within the pile are made from correlation of the chemical analyses results with the drilling history, in particular the change from diesel to low toxicity base oil in 1984. Strong gradients were found in the faunal data which correlate well with the physical and chemical results. Dense populations of opportunists species were present adjacent to the platform, including a novel molluscan opportunist. This is the first comprehensive study of an oily cuttings pile and is a contribution to the debate on their long term impact and fate on abandonment

  12. Passive magnetic bearing configurations

    Science.gov (United States)

    Post, Richard F [Walnut Creek, CA

    2011-01-25

    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  13. Improved gas thrust bearings

    Science.gov (United States)

    Anderson, W. J.; Etsion, I.

    1979-01-01

    Two variations of gas-lubricated thrust bearings extend substantially load-carrying range over existing gas bearings. Dual-Action Gas Thrust Bearing's load-carrying capacity is more than ninety percent greater than that of single-action bearing over range of compressibility numbers. Advantages of Cantilever-mounted Thrust Bearing are greater tolerance to dirt ingestion, good initial lift-off characteristics, and operational capability over wide temperature range.

  14. Multi-scale sensitivity analysis of pile installation using DEM

    Science.gov (United States)

    Esposito, Ricardo Gurevitz; Velloso, Raquel Quadros; , Eurípedes do Amaral Vargas, Jr.; Danziger, Bernadete Ragoni

    2017-12-01

    The disturbances experienced by the soil due to the pile installation and dynamic soil-structure interaction still present major challenges to foundation engineers. These phenomena exhibit complex behaviors, difficult to measure in physical tests and to reproduce in numerical models. Due to the simplified approach used by the discrete element method (DEM) to simulate large deformations and nonlinear stress-dilatancy behavior of granular soils, the DEM consists of an excellent tool to investigate these processes. This study presents a sensitivity analysis of the effects of introducing a single pile using the PFC2D software developed by Itasca Co. The different scales investigated in these simulations include point and shaft resistance, alterations in porosity and stress fields and particles displacement. Several simulations were conducted in order to investigate the effects of different numerical approaches showing indications that the method of installation and particle rotation could influence greatly in the conditions around the numerical pile. Minor effects were also noted due to change in penetration velocity and pile-soil friction. The difference in behavior of a moving and a stationary pile shows good qualitative agreement with previous experimental results indicating the necessity of realizing a force equilibrium process prior to any load-test to be simulated.

  15. Evaluation of bearing capacity of piles from cone penetration test data.

    Science.gov (United States)

    2007-12-01

    A statistical analysis and ranking criteria were used to compare the CPT methods and the conventional alpha design method. Based on the results, the de Ruiter/Beringen and LCPC methods showed the best capability in predicting the measured load carryi...

  16. Ground Vibration Isolation of Multiple Scattering by Using Rows of Tubular Piles as Barriers

    Directory of Open Access Journals (Sweden)

    Miao-miao Sun

    2014-01-01

    Full Text Available A new formal solution for the multiple scattering of plane harmonic waves by a group of arbitrary configuration tubular piles in an elastic total space is derived. Each order of scattering satisfies prescribed boundary conditions at the interface of tubular piles, which is delivered as the sum of incident and scattering waves. The first order performs the scattering wave by each scattered pile and the subsequent orders resulted from the excitation of each pile of first order of scattering from the remaining tubular piles. Advanced scattering orders can be regarded as the same manners. Several series of scattering coefficients are figured out with the aids of addition theorem so that the exact steady-state solution for the scattered displacement and stress is obtained. Particularly, when internal diameter of tubular piles tends to be infinitely small, it degenerates to a solid pile problem. By imposing the normalized displacement amplitudes and transmissibility indices, the influences of specific parameters such as scattering orders, internal and external diameter ratio of piles, pile material rigidity, position and distances between tubular pile and pile rows, and pile numbers are discussed. Certain recommended conclusions have been drawn as the guidelines of practical engineering design for discontinuous barrier of tubular piles.

  17. Seismic soil-structure interaction of foundations with large piles

    International Nuclear Information System (INIS)

    Zeevaert, L.

    1996-01-01

    In seismic regions with soft soil deposits subjected to ground surface subsidence, there is the necessity to support the weight of constructions on large diameter piles or piers hearing on deep firm strata. To justify the action of these elements working under flexo compression and shear, it is necessary to perform calculations of soil pile interaction from a practical engineering point of view and estimate the order of magnitude of the forces and displacements to which these elements will be subjected during the seismic action assigned to the foundation. In this paper we defined a pier as a large diameter pile constructed on site. Furthermore, in the seismic analysis it is necessary to evaluate the seismic pore water pressure to learn on the effective seismic soil stresses close to the ground surface. (author)

  18. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    in dry sand by use of centrifuge modelling and to compare the findings with the standard p-y curves. It has been chosen to apply piles with an embedment length of 6 to 10 times the diameter of the applied piles. The general static behaviour of monopiles in dry sand has based on centrifuge tests been...... initial response and a higher ultimate capacity. The initial stiffness of the soil-structure interaction measured in the centrifuge tests, equivalent to initial stiffness of p-y curves, shows a dependency of depth and diameter. Control issues in relation to cyclic tests have resulted in tests...... on the structure and the productivity of the turbine. Current design practice for monopiles are based on p-y curves developed for slender piles with a diameter of 0.6 m. The focus on the structure stiffness has entailed a significant research on the soil-structure interaction for large diameter monopiles...

  19. ESTIMATION OF AGING EFFECTS OF PILES IN MALAYSIAN OFFSHORE LOCATIONS

    Directory of Open Access Journals (Sweden)

    JERIN M. GEORGE

    2017-04-01

    Full Text Available An increasing demand for extending life and subsequently higher loading requirements of offshore jacket platforms are among the key problems faced by the offshore industry. The Aging effect has been proved to increase the axial capacity of piles, but proper methods to estimate and quantify these effects have not been developed. Borehole data from ten different Malaysian offshore locations have been analysed and they were employed to estimate the setup factor for different locations using AAU method. The setup factors found were used in the Skov and Denver equation to calculate capacity ratios of the offshore piles. The study showed that there will be an average improvement in the axial capacity of offshore piles by 42.2% and 34.9% for clayey and mixed soils respectively after a time equal to the normal design life (25 years of a jacket platform.

  20. Statistical Estimation of Subgrade Reaction Coefficient For Horizontally Loaded Piles

    International Nuclear Information System (INIS)

    Honjo, Yusuke; Zaika, Yulvi; Pokharel, Gyaneswor

    2002-01-01

    Appropriate horizontal subgrade reaction (k h ) is required to evaluate stress and displacement in horizontal loading pile. In order to obtain more accurate prediction of pile behavior, statistical analysis is employed. Based on 21 data set gathered on horizontal loading piles, inverse analysis and regression analysis are carried out. The main value and uncertainty are obtained by inverse analysis, could be employed in the regression analysis. The relationship between the lateral resistant constant (k c ) and SPT N value takes into account in correlated and uncorrelated condition. The results are compared with Port and Harbor Technical Research Institute (JPHA, 1999) and Japan Highway Bridge Specification IV (JRA, 1996). The computed values are found to be very close to the JPHA line and within the range of JRA lines in diameter 0.5 m and 2 m

  1. Cascades of pile-up and dead time

    International Nuclear Information System (INIS)

    Pomme, S.

    2008-01-01

    Count loss through a cascade of pile-up and dead time is studied. Time interval density-distribution functions and throughput factors are presented for counters with a series arrangement of pile-up and extending or non-extending dead time. A counter is considered, where an artificial dead time is imposed on every counted event, in order to control the length and type of dead time. For such a system, it is relatively easy to determine an average count-loss correction factor via a live-time clock gated by the imposed dead-time signal ('live-time mode'), or otherwise to apply a correction factor based on the inversion of the throughput function ('real-time mode'). However, these techniques do not account for additional loss through pulse pile-up. In this work, counting errors associated with neglecting cascade effects are calculated for measurements in live-time and real-time mode

  2. Constituent-level pile-up mitigation techniques in ATLAS

    CERN Document Server

    The ATLAS collaboration

    2017-01-01

    Pile-up of simultaneous proton-proton collisions at the LHC has a significant impact on jet reconstruction. In this note the performance of several pile-up mitigation techniques is evaluated in detailed simulations of the ATLAS experiment. Four algorithms that act on the jet-constituent level are evaluated: SoftKiller, the cluster vertex fraction algorithm and Voronoi and constituent subtraction. We find that application of these constituent-level algorithms improves the resolution of low-transverse-momentum jets. The improvement is significant for collisions with 80-200 simultaneous proton-proton collisions envisaged in future runs of the LHC.

  3. Centrifuge modelling of a laterally cyclic loaded pile

    DEFF Research Database (Denmark)

    Klinkvort, Rasmus Tofte; Leth, Caspar Thrane; Hededal, Ole

    2010-01-01

    A total number of 9 static and 6 cyclic centrifuge tests on laterally loaded piles in very dense, dry sand was erformed. The prototype dimensions of the piles were 1 meter in diameter and penetration depths varying from 6 to 10 meters. The static tests were used to investigate the initial subgrade...... reaction modulus and as a reference for cyclic tests. For the cyclic tests the accumulation of deflections and the change in secant stiffness of the soil from repetitive loading were investigated. From all the tests carried out accumulations of deflections were seen. rom the centrifuge tests it was seen...

  4. Load and resistance factor design of bridge foundations accounting for pile group-soil interaction.

    Science.gov (United States)

    2015-11-01

    Pile group foundations are used in most foundation solutions for transportation structures. Rigorous and reliable pile design methods are : required to produce designs whose level of safety (probability of failure) is known. By utilizing recently dev...

  5. Load rating and retrofit testing of bridge timber piles subjected to eccentric loading.

    Science.gov (United States)

    2012-11-01

    This report first evaluated the load rating procedure currently in use by the Illinois Department of Transportation (IDOT) for rating timber : piles supporting multiple-span, simply supported bridges. For simplicity, these piles are often rated under...

  6. Assessment and evaluation of timber piles used in Nebraska for retrofit and rating.

    Science.gov (United States)

    2014-04-01

    The cost of an effective retrofitting and rehabilitation of timber piles is less than cost of replacing the piles. However, some of the retrofit options used in Nebraska failed to result in the expected performance levels. Further, design and detaili...

  7. Production and marketing of wood piling and poles in the Northeast

    Science.gov (United States)

    Myron D. Ostrander

    1953-01-01

    Since the earliest colonial settlements along the northeastern seaboard, wood piling has been used for wharves and piers and other waterfront structures. As waterside industries and waterborne commerce grew, the demand for wood piling grew.

  8. Behavior of Pile to Bent Cap Connections Subjected to Seismic Forces

    Science.gov (United States)

    2012-06-01

    Currently the South Carolina Department of Transportation employs a detail of a plain pile embedment for the : connection between precast prestressed piles and cast-in-place bent caps. This connection has proved beneficial in terms : of time and cost...

  9. The response of pile-guided floats subjected to dynamic loading : volume I final report.

    Science.gov (United States)

    2014-08-01

    Pile : - : Guided floats can be a desirable alternative to stationary berthing structures. Both floats and guide piles are subjected to dynamic : forces such as wind generated waves and impacts from vessels. This project developed a rational basis fo...

  10. Analytical Method Used to Calculate Pile Foundations with the Widening Up on a Horizontal Static Impact

    Science.gov (United States)

    Kupchikova, N. V.; Kurbatskiy, E. N.

    2017-11-01

    This paper presents a methodology for the analytical research solutions for the work pile foundations with surface broadening and inclined side faces in the ground array, based on the properties of Fourier transform of finite functions. The comparative analysis of the calculation results using the suggested method for prismatic piles, piles with surface broadening prismatic with precast piles and end walls with precast wedges on the surface is described.

  11. THREE-DIMENSIONAL NONLINEAR FINITE ELEMENT MODELING FOR LATERALLY LOADED VERTICAL PILES

    Directory of Open Access Journals (Sweden)

    M. Kubilay KELESOĞLU

    2006-01-01

    Full Text Available This paper presents a study for laterally loaded free head concrete piles using the finite element method (FEM. The finite element mesh is constituted from three-dimensional elements. The pile and soil boundary are defined cylindrically while lateral load is defined as single concentrated load from the top of the pile head. Various types of soil and pile properties are analysed and the load-deformation curves for different types of soils namely, sands and clays are evaluated.

  12. Out-of-pile and in-pile temperature noise investigations: a survey of methods results and models

    International Nuclear Information System (INIS)

    Dentico, G.; Giovannini, R.; Marseguerra, M.; Pacilio, N.; Taglienti, S.; Tosi, V.; Vigo, A.; Oguma, R.

    1982-01-01

    A review is given of the main results obtained from temperature noise measurements performed in out-of-pile sodium loops on fast fuel element mock-ups. Sources of data were thermocouples placed in the central axis of the channel downstream from the bundle end. Autoregressive moving average (ARMA) models have been applied to several temperature time series; the analysis shows that a simple ARMA (3, 2) model adequately accounts for the observed fluctuations. Finally, highlights of a heat transfer stochastic model are also reported together with a preliminary validation against in-pile experimental data. (author)

  13. 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

  14. Experimental study on performance of laterally loaded plumb and battered piles in layered sand

    Directory of Open Access Journals (Sweden)

    Bushra S. Albusoda

    2017-09-01

    Full Text Available This study introduces a series of single and pile group model tests subjected to lateral loads in . multilayered sand from Karbala, Iraq. The aim of this study is to investigate: the performance of the pile groups subjected to lateral loads; in which the pile batter inclination angle is changed; the effect of pile spacing (s/d ratio, the influence of using different number of piles and pile group configuration. Results revealed that the performance of single negative (Reverse Battered piles with inclination of 10° and 20° show a gain of 32% and 76 % in the ultimate lateral capacity over the regular ones. For pile groups, the use of a combination of regular, negative and positive battered piles in different angles of inclination within the same group shows a significant increase in the ultimate lateral load carrying capacity. Increasing the spacing between piles in groups of the same category shows an increase in the group efficiency, also changing the piles number within the group by using different patterns will influence the ultimate lateral resistance of the pile group.

  15. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.24 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products composed thereof may be...

  16. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may be...

  17. Three dimensional modeling of laterally loaded pile groups resting in sand

    Directory of Open Access Journals (Sweden)

    Amr Farouk Elhakim

    2016-04-01

    Full Text Available Many structures often carry lateral loads due to earth pressure, wind, earthquakes, wave action and ship impact. The accurate predictions of the load–displacement response of the pile group as well as the straining actions are needed for a safe and economic design. Most research focused on the behavior of laterally loaded single piles though piles are most frequently used in groups. Soil is modeled as an elastic-perfectly plastic model using the Mohr–Coulomb constitutive model. The three-dimensional Plaxis model is validated using load–displacement results from centrifuge tests of laterally loaded piles embedded in sand. This study utilizes three dimensional finite element modeling to better understand the main parameters that affect the response of laterally loaded pile groups (2 × 2 and 3 × 3 pile configurations including sand relative density, pile spacing (s = 2.5 D, 5 D and 8 D and pile location within the group. The fixity of the pile head affects its load–displacement under lateral loading. Typically, the pile head may be unrestrained (free head as the pile head is allowed to rotate, or restrained (fixed head condition where no pile head rotation is permitted. The analyses were performed for both free and fixed head conditions.

  18. Rehabilitating slash pile burn scars in upper montane forests of the Colorado Front Range

    Science.gov (United States)

    Paula J. Fornwalt; Charles C. Rhoades

    2011-01-01

    Slash pile burning is widely conducted by land managers to dispose of unwanted woody fuels, yet this practice typically has undesirable ecological impacts. Simple rehabilitation treatments may be effective at ameliorating some of the negative impacts of pile burning on plants and soils. Here, we investigated: (1) the impacts of slash pile burning on soil nitrogen and...

  19. Free vibration of semi-rigid connected Reddy–Bickford piles ...

    Indian Academy of Sciences (India)

    The literature on free vibration analysis of Bernoulli–Euler and timoshenko piles embedded in elastic soil is plenty, but that of Reddy–Bickford piles partially embedded in elastic soil with/without axial force effect is fewer. The soil that the pile partially embedded in is idealized by Winkler model and is assumed to be ...

  20. 75 FR 67951 - Takes of Marine Mammals Incidental to Specified Activities; Piling and Structure Removal in...

    Science.gov (United States)

    2010-11-04

    ... mammals, by harassment, incidental to derelict creosote piling and structure removal within the Woodard... authorization to take, by harassment, small numbers of marine mammals incidental to derelict creosote piling and... restoration effort. The piles designated to be removed have been treated with creosote, a wood preservative...

  1. 75 FR 48941 - Takes of Marine Mammals Incidental to Specified Activities; Piling and Structure Removal in...

    Science.gov (United States)

    2010-08-12

    ..., by harassment, incidental to derelict creosote piling and structure removal within the Woodard Bay... incidental to derelict creosote piling and structure removal associated with a habitat restoration project... proposed project involves the removal of 615 creosote treated wood pilings and overwater creosoted...

  2. Experiments with needle bearings

    Science.gov (United States)

    Ferretti, Pericle

    1933-01-01

    Experiments and results are presented in testing needle bearings, especially in comparison with roller bearings. Reduction in coefficient of friction is discussed as well as experimental methods and recording devices.

  3. Pigeon-Frequented Areas, Garbage Piles and Dog Faeces as ...

    African Journals Online (AJOL)

    A study was carried out to establish the presence of Cryptococcus neoformans and Candida species in two pigeon-frequented areas; garbage piles from two separate sites in Nairobi, and dog faeces from Small animal clinic, University of Nairobi, Kabete. The sampling included both solid materials and air. Potato Dextrose ...

  4. Design and construction of precast piles with stainless reinforcing steel.

    Science.gov (United States)

    2014-02-01

    The service life of prestressed concrete piles is, in part, dictated by the time required to corrode the steel once : chloride ions are at the surface of the steel. Stainless steel materials, although limited in availability in strand : form, have a ...

  5. Vision-based autonomous grasping of unknown piled objects

    International Nuclear Information System (INIS)

    Johnson, R.K.

    1994-01-01

    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

  6. Finite element analysis of soil-sheet pile interaction

    Science.gov (United States)

    Nyby, D. W.

    A finite element model which accurately and economically models soil-sheet pile structures was developed. The model was used to analyze cantilever and anchored sheet pile walls. The finite element model includes transition and interface elements. The transition element has the capability of conforming to the displaced shape of the sheet pile elements on one side (cubic element) and soil elements on the other sides (bilinear element). The interface element models the frictional resistance between the soil and the sheet pile. It behaves elastically below a threshold force level (Coulomb friction) and perfectly plastic above this value. The soil is modeled using nonlinear constitutive relations. These relations are used for both the transition elements and the bilinear elements. The economy of the finite element model was increased in two ways. Closed-form integration was used to reduce the computational effort and an equation solver was used which takes advantage of the banded, symmetric, and positive-definite characteristics of the global stiffness matrix.

  7. 20051655 - Petronas, Capacity of Driven Piles Offshore Malaysia

    DEFF Research Database (Denmark)

    Augustesen, Anders

    This report presents the results of work carried out by Aalborg Univesity for NGI related to the effects of ageing on the axial capacity of piles in clay and sand. The document is the fourth of four notes regarding the subject and it includes a recommended approach to account for ageing effects...

  8. 20051655 - Petronas, Capacity of Driven Piles Offshore Malaysia

    DEFF Research Database (Denmark)

    Augustesen, Anders

    This document is one of four notes concerning the effects of time (in this case ageing) on the vertical capacity of piles. It includes summaries of relevant publications related to the topic. Further, focus has been paid to publications that deal with quantification of setup and not the mechanisms...

  9. Numerical experiments with rubble piles : equilibrium shapes and spins

    NARCIS (Netherlands)

    Richardson, Derek C.; Elankumaran, Pradeep; Sanderson, Robyn E.

    2005-01-01

    We present numerical experiments investigating the shape and spin limits of self-gravitating "perfect" rubble piles that consist of identical, smooth, rigid, spherical particles with configurable normal coefficient of restitution and no sliding friction. Such constructs are currently employed in a

  10. Aerial sampling of emissions from biomass pile burns in ...

    Science.gov (United States)

    Emissions from burning piles of post-harvest timber slash in Grande Ronde, Oregon were sampled using an instrument platform lofted into the plume using a tether-controlled aerostat or balloon. Emissions of carbon monoxide, carbon dioxide, methane, particulate matter (PM2.5 µm), black carbon, ultraviolet absorbing PM, elemental/organic carbon, semi-volatile organics (polycyclic aromatic hydrocarbons and polychlorinated dibenzodioxins/dibenzofurans), filter-based metals, and volatile organics were sampled for determination of emission factors. The effect on emissions from covering or not covering piles with polyethylene sheets to prevent fuel wetting was determined. Results showed that the uncovered (“wet”) piles burned with lower combustion efficiency and higher emissions of volatile organic compounds. Results for other pollutants will also be discussed. This work determined the emissions from open burning of forest slash wood, with and without plastic sheeting. The foresters advocate the use of plastic to keep the slash wood dry and aid in the controlled combustion of the slash to reduce fuel loading. Concerns about the emissions from the burning plastic prompted this work which conducted an extensive characterization of dry, wet, and dry with plastic slash pile emissions.

  11. Aerial Sampling of Emissions from Biomass Pile Burns in Oregon

    Science.gov (United States)

    Emissions from burning piles of post-harvest timber slash in Grande Ronde, Oregon were sampled using an instrument platform lofted into the plume using a tether-controlled aerostat or balloon. Emissions of carbon monoxide, carbon dioxide, methane, particulate matter (PM2.5 µm), ...

  12. Piles, tabs and overlaps in navigation among documents

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper

    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...

  13. Rapid pile load tests in the geotechnical centrifuge

    NARCIS (Netherlands)

    Holscher, P.; Van Tol, A.F.; Huy, N.Q.

    2012-01-01

    Centrifiige experiments were carried out to gain insight into the factors that affect the mobilized resistance during rapid load testing on piles in sand. The influence of generated pore water pressure during rapid load tests is shidied, and its effect on the commonly used unloadmg point method to

  14. Digitalisation in atomic pile control (1962); La digitalisation 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

    A brief survey is first given of the general theorems of Boodle's algebra and of sequence systems using D.A. Huffmans theory. Some indications are then given concerning the setting-up and the operation of digital computers and also of the principal codes used in digital techniques. It is then shown how digitalisation in atomic pile control makes it possible to use new techniques having the following advantages in particular: greater working safety, a higher degree of centralisation, and suppression of the linear elements. A few examples are given of the application of these techniques to control, particularly with respect to the measurement of the neutronic power and of the period and also of course, to the treatment of the data and the sequence automatisms. The advantage of using digital techniques in the shutdown channels is also examined. Finally a review is given of the technology and the viability of the control devices used. (author) [French] On rappelle d'abord ici les theoremes generaux de l'algebre de Boole et des systemes a sequences en s'appuyant sur la theorie de D.A. Huffmann. On donne ensuite quelques indications sur l'agencement et le fonctionnement des calculateurs digitaux ainsi que les principaux codes utilises dans les techniques digitales. On montre alors comment la digitalisation dans le controle des piles atomiques permet d'utiliser de nouvelles techniques presentant principalement les avantages suivants: securite de fonctionnement plus grande, centralisation plus elevee et suppression des elements lineaires. Un certain nombre d'exemples sont donnes sur l'application de ces techniques au controle, particulierement en ce qui concerne la mesure de la puissance neutronique, de la periode et aussi bien entendu du traitement des informations et des automatismes a sequences. On analyse aussi l'avantage de l'utilisation des techniques digitales dans les chaines de securite. Enfin, un apercu est donne

  15. Enhanced mixing downstream of a pile in an estuarine flow

    Science.gov (United States)

    Lass, H. U.; Mohrholz, V.; Knoll, M.; Prandke, H.

    2008-11-01

    We studied the impact on stratification and mixing of a bridge pile in a stratified shear flow at the Western Bridge of the Great Belt Fixed Link, Denmark, in January and April 2006. Stratification was measured with high horizontal resolution by towed CTD chains and dissipation of turbulent kinetic energy was measured by a free-falling MSS 90 microstructure profiler equipped with shear probes. Background stratification and current were measured by standard CTD and a bottom-mounted ADCP, respectively. The spatial and temporal variability of the flow field close behind a single pile was measured by an ADCP mounted on a small catamaran tethered to this pile. A shear background flow of varying strength was observed with an inflow of up to 80 cm s - 1 in the surface layer and an outflow of 10 cm s - 1 in the bottom layer. The brackish surface layer was separated from the saline Kattegat water in the bottom layer by an intermediate layer resulting in a Brunt-Väisälä frequency of up to 100 cycles per hour (cph). The maximum Reynolds number ( Re) and internal Froude number ( Fr) were 4.6 × 10 6 and 1.3, respectively. Eddies occurred downstream of a pile with a characteristic diameter of the pile and a frequency corresponding to a von Kármán vortex street when near-surface Fr > 0.7. Enhanced mixing was observed in the von Kármán vortex streets, which caused an increase in salinity by a few psu in the surface mixed layer of the eddy up to 400 m downstream of the piles. Differential advection by cross-channel circulation smeared out laterally from the wakes' salinity anomalies and turbulence. The dissipation of turbulent kinetic energy in the intermediate layer increased by an order of magnitude downstream of the piles as a function of Fr when Fr > 0.7. This enhanced mixing reduced the mean potential energy anomaly downstream by some 10 Jm - 3 in the upper 15 m depth and caused an upstream-directed baroclinic pressure gradient of the same order as the barotropic

  16. Teddy Bear Stories

    DEFF Research Database (Denmark)

    van Leeuwen, Theo; Caldas-Coulthardt, Carmen

    2014-01-01

    This paper presents a semiotic analysis of a key cultural artefact, the teddy bear. After introducing the iconography of the teddy bear, it analyses different kinds of stories to show how teddy bears are endowed with meaning in everyday life: stories from children's books, reminiscenses by adults...... about their childhood teddy bears, and children's accounts of what they do with teddy bears, both written for school and told 'out of school', The chapter sees teddy bears as artefacts that provide a cultural channeling for the child's need of a transitional object and argues that the meanings of teddy...... bears have traditionally centred on interpersonal relations within the nuclear family, but have recently been institutionalized and commercialized....

  17. A Numerical Simulation of Base Shear Forces and Moments Exerted by Waves on Large Diameter Pile

    Directory of Open Access Journals (Sweden)

    You-liang Cheng

    2017-01-01

    Full Text Available To solve the problem of the dynamic variation of wave force diameter of pile foundation for offshore wind turbines, wave force and moment of large diameter pile foundation can be calculated. In this paper, simulation technique is used to calculate the wave force and moment of different large diameter pile foundation, and the base shear force and moment of the interval 20-degree phase angle are obtained by the base line of the pile. Under the action of a certain load, the complete stress variation of the pile foundation is obtained. According to the basic principle of diffraction theory, the process curve of large diameter pile, and analysis of wave force, diffraction force changes in a certain period of time interval. The results show that the wave after the large diameter pile formed around the vortex, large diameter pile base shear, and moment dynamic change is nonlinear in a complete cycle, the diameter of the pile increases by 0.5 m, and the wave force increases by about 5%, the results show that it provides certain reference value for the offshore pile foundation pile with large diameter primary site. Some significant results for practical application are discussed.

  18. An experimental study on pile spacing effects under lateral loading in sand.

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    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.

  19. Field Tests to Investigate the Penetration Rate of Piles Driven by Vibratory Installation

    Directory of Open Access Journals (Sweden)

    Zhaohui Qin

    2017-01-01

    Full Text Available Factors directly affecting the penetration rate of piles installed by vibratory driving technique are summarized and classified into seven aspects which are driving force, resistance, vibratory amplitude, energy consumption, speeding up at the beginning, pile plumbness keeping, and slowing down at the end, from the mechanism and engineering practice of the vibratory pile driving. In order to find out how these factors affect the penetration rate of the pile in three major actors of vibratory pile driving: (i the pile to be driven, (ii the selected driving system, and (iii the imposed soil conditions, field tests on steel sheet piles driven by vibratory driving technique in different soil conditions are conducted. The penetration rates of three different sheet pile types having up to four different lengths installed using two different vibratory driving systems are documented. Piles with different lengths and types driven with or without clutch have different penetration rates. The working parameters of vibratory hammer, such as driving force and vibratory amplitude, have great influences on the penetration rate of the pile, especially at the later stages of the sinking process. Penetration rate of piles driven in different soil conditions is uniform because of the different penetration resistance including shaft friction and toe resistance.

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

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    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. PMID:24453900

  1. Bending Moment Calculations for Piles Based on the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Yu-xin Jie

    2013-01-01

    Full Text Available Using the finite element analysis program ABAQUS, a series of calculations on a cantilever beam, pile, and sheet pile wall were made to investigate the bending moment computational methods. The analyses demonstrated that the shear locking is not significant for the passive pile embedded in soil. Therefore, higher-order elements are not always necessary in the computation. The number of grids across the pile section is important for bending moment calculated with stress and less significant for that calculated with displacement. Although computing bending moment with displacement requires fewer grid numbers across the pile section, it sometimes results in variation of the results. For displacement calculation, a pile row can be suitably represented by an equivalent sheet pile wall, whereas the resulting bending moments may be different. Calculated results of bending moment may differ greatly with different grid partitions and computational methods. Therefore, a comparison of results is necessary when performing the analysis.

  2. Bearings: Technology and needs

    Science.gov (United States)

    Anderson, W. J.

    1982-01-01

    A brief status report on bearing technology and present and near-term future problems that warrant research support is presented. For rolling element bearings a material with improved fracture toughness, life data in the low Lambda region, a comprehensive failure theory verified by life data and incorporated into dynamic analyses, and an improved corrosion resistant alloy are perceived as important needs. For hydrodynamic bearings better definition of cavitation boundaries and pressure distributions for squeeze film dampers, and geometry optimization for minimum power loss in turbulent film bearings are needed. For gas film bearings, foil bearing geometries that form more nearly optimum film shapes for maximum load capacity, and more effective surface protective coatings for high temperature operation are needed.

  3. Development of in-pile test and evaluation technology

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yung Hwan; Park, Jong Man; Joo, Kee Nam; Park, Duk Keun; Park, Se Jin; Oh, Jong Myung; Kim, Tae Ryong; Park Jin Suk; Lee, Jae Han [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-08-01

    To develop the in-pile test and evaluation technologies using KMRR, basic design of instrumented capsule and auxiliary system for material irradiation test and the related studies are performed. First, reactor and test hole characteristics are summarized, and conceptual design requirements of capsule to KMRR are reviewed. And fundamental principles and criteria for the instrumented capsule design are summarized. Basic design and analysis of instrumented capsule are performed, and design of capsule supporting system are also performed and structural integrity of the system is analyzed. Based on the prior studies, test mock-ups are designed and manufactured, and thermohydraulic and vibration tests are prepared. And, as in-pile test evaluation technologies, KMRR neutron dosimetry and mechanical tests related to material irradiation are investigated. 67 figs, 30 tabs, 41 refs. (Author).

  4. Collapse mechanisms and strength prediction of reinforced concrete pile caps

    DEFF Research Database (Denmark)

    Jensen, Uffe G.; Hoang, Linh Cao

    2012-01-01

    This paper describes an upper bound plasticity approach for strength prediction of reinforced concrete pile caps. A number of collapse mechanisms are identified and analysed. The procedure leads to an estimate of the load-carrying capacity and an identification of the critical collapse mechanism....... Calculations have been compared with nearly 200 test results found in the literature. Satisfactory agreement has been found. The analyses are conducted on concentrically loaded caps supported by four piles. The paper briefly outlines how the approach may be extended to more complicated loadings and geometries....... It is argued that the upper bound approach may be a useful complement to the widely used lower bound strut-and-tie method. Especially when dealing with strength assessment of existing structures....

  5. The Supercritical Pile Model: Prompt Emission Across the Electromagnetic Spectrum

    Science.gov (United States)

    Kazanas, Demos; Mastichiadis, A.

    2008-01-01

    The "Supercritical Pile" GRB model is an economical model that provides the dissipation necessary to convert explosively the energy stored in relativistic protons in the blast wave of a GRB into radiation; at the same time it produces spectra whose luminosity peaks at 1 MeV in the lab frame, the result of the kinematics of the proton-photon - pair production reaction that effects the conversion of proton energy to radiation. We outline the fundamental notions behind the "Supercritical Pile" model and discuss the resulting spectra of the prompt emission from optical to gamma-ray energies of order Gamma^2 m_ec^2, (Gamma is the Lorentz factor of the blast wave) present even in the absence of an accelerated particle distribution and compare our results to bursts that cover this entire energy range. Particular emphasis is given on the emission at the GLAST energy range both in the prompt and the afterglow stages of the burst.

  6. Accelerating transient drainage from UMTRA Project tailings piles

    International Nuclear Information System (INIS)

    1990-09-01

    The period between the completion of construction of the tailings disposal cell and the establishment of equilibrium moisture content and seepage conditions is considered to be the period of transient drainage. Transient drainage may be due to factors such as construction water, precipitation, or residual water from the milling process. Transient seepage rates usually exceed steady state seepage rates. If the transient seepage rate causes contaminant levels to exceed groundwater compliance standards, then an alternative groundwater compliance strategy or technical approach to reduce or mitigate the effects of the drainage must be adopted. This study examines methods to accelerate the transient drainage of soils and hence to remove excess pore water from tailings in UMTRA Project disposal cells. The technical and economic feasibility of possible methods is examined. In order to perform comparative economical analyses of the various methods, an example tailings pile is postulated. This pile is considered to be 300 meters by 300 meters by 10 meters in thickness

  7. From the pile of Volta to fuel cells

    CERN Multimedia

    2000-01-01

    Volta designed his pile by associating two different metals and liquid conducting electricity. He recognized the possibility of increasing the "voltage" by placing cells in series (a pile). This invention led to a wonderful development of science and technology, including the concept of fuel cell in 1839 by GROVE. But efficient research began only in the 20th century after the development of electrochemical thermodynamics by Nemst. His assistants conducted research on fuel cell designed by Bacon before world warII, developed NASA for the Apollo space flights. Research for effecient and clean electricity generation has led to the defferent kinds of fuel cells now under development (APC, PAPC, PAMPC, MCPC and SOPC) which will be briefly described with their applications.

  8. Polar bears, Ursus maritimus

    Science.gov (United States)

    Rode, Karyn D.; Stirling, Ian

    2017-01-01

    Polar bears are the largest of the eight species of bears found worldwide and are covered in a pigment-free fur giving them the appearance of being white. They are the most carnivorous of bear species consuming a high-fat diet, primarily of ice-associated seals and other marine mammals. They range throughout the circumpolar Arctic to the southernmost extent of seasonal pack ice.

  9. In-pile experimental facility needs for LMFR safety research

    International Nuclear Information System (INIS)

    Kawata, Norio; Niwa, Hajime

    1994-01-01

    Although the achievement of the safety research during the past years has been significant, there still exists a strong need for future research, especially when there is prospect for future LMFR commercialization. In this paper, our current views are described on future research needs especially with a new in-pile experimental facility. The basic ideas and progress are outlined of a preliminary feasibility study. (author)

  10. Thermal response testing of precast pile heat exchangers

    DEFF Research Database (Denmark)

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

    The report is organized as follows: first, the concept of TRT is explained. Second, the test sites are described. Third, the field work is presented and a summary of the future work regarding the methodology to treat the data from the tests is provided. Finally, further documentation of the field...... of the fieldwork, the pile heat exchangers and the TRT equipment is extended in diverse appendices....

  11. In-pile loop experiments in water chemistry and corrosion

    International Nuclear Information System (INIS)

    Kysela, J.; Jindrich, K.; Masarik, V.; Fric, Z.; Chotivka, V.; Hamerska, H.; Vsolak, R.; Erben, O.

    1986-08-01

    Methods and techniques used were as follows: (a) Method of polarizing resistance for remote monitoring of instantaneous rate of uniform corrosion. (b) Out-of-pile loop at the temperature 350 degC, pressure 19 MPa, circulation 20 kgs/h, testing time 1000 h. (c) High temperature electromagnetic filter with classical solenoid and ball matrix for high pressure filtration tests. (d) High pressure and high temperature in-pile water loop with coolant flow rate 10 000 kgs/h, neutron flux in active channel 7x10 13 n/cm 2 .s, 16 MPa, 330 degC. (e) Evaluation of experimental results by chemical and radiochemical analysis of coolant, corrosion products and corrosion layer on surface. The results of measurements carried out in loop facilities can be summarized into the following conclusions: (a) In-pile and out-of-pile loops are suitable means of investigating corrosion processes and mass transport in the nuclear power plant primary circuit. (b) In studying transport phenomena in the loop, it is necessary to consider the differences in geometry of the loop and the primary circuit, mainly the ratio of irradiated and non-irradiated surfaces and volumes. (c) In the experimental facility simulating the WWER-type nuclear power plant primary circuit, solid suspended particles of a chemical composition corresponding most frequently to magnetite or nickel ferrite, though with non-stoichiometric composition Me x 2+ Fe 3-x 3+ O 4 , were found. (d) Continuous filtration of water by means of an electromagnetic filter removing large particles of corrosion products leads to a decrease in radioactivity of the outer epitactic layer only. The effect of filtration on the inner topotactic layer is negligible

  12. The MOZART in-pile tritium extraction experiment

    International Nuclear Information System (INIS)

    Briec, M.

    1990-01-01

    In-pile tritium extraction behavior of various ceramics was compared in the MOZART experiment. The influence of temperature and purge gas composition was studied. The experimental results are analyzed by taking into account the processes of diffusion in the grain and desorption at grain surface. This analysis confirms that a better knowledge of the desorption process is necessary for a satisfactory explanation of the experimental data

  13. Placement of mass concrete for cast-in-place concrete piling : the effects of heat of hydration of mass concrete for cast-in-place piles.

    Science.gov (United States)

    2008-12-01

    This report describes models, ABAQUS and Schmidt, to predict the peak temperature in the center of cast-in-place concrete piling. Five concrete piles with varying diameters and made up of concrete mixes with different percentage of fly ash are used. ...

  14. Program of in-pile IASCC testing under the simulated actual plant condition. Development of technique for in-pile IASCC initiation test in JMTR

    International Nuclear Information System (INIS)

    Ugachi, Hirokazu; Tsukada, Takashi; Kaji, Yoshiyuki; Nagata, Nobuaki; Dozaki, Koji; Takiguchi, Hideki

    2003-01-01

    Irradiation assisted stress corrosion cracking (IASCC) is caused by the synergistic effects of neutron irradiation, stress and corrosion by high temperature water. It is, therefore, essential to perform in-pile SCC tests, which are material tests under the conditions simulating those of actual LWR operation, in order to clarify the precise mechanism of the phenomenon, though mainly out-of-pile SCC tests for irradiated materials have been carried out in this research field. There are, however, many difficulties to perform in-pile SCC tests. Performing in-pile SCC tests, essential key techniques must be developed. Hence as a part of development of the key techniques for in-pile SCC tests, we have embarked on development of the test technique which enables us to obtain the information concerning the effect of such parameters as applied stress level, water chemistry, irradiation conditions, etc. on the crack initiation behavior. Although it is difficult to detect the crack initiation in in-pile SCC tests, the crack initiation can be evaluated by the detection of specimen rupture if the cross section area of the specimen is small enough. Therefore, we adopted the uniaxial constant loading (UCL) test with small tensile specimens. This paper will describe the current status of the development of several techniques for in-pile SCC initiation tests in JMTR and the results of the performance tests of the designed testing unit using the out-of-pile loop facility. (author)

  15. EcoBears

    DEFF Research Database (Denmark)

    Nielsen, Nick; Pedersen, Sandra Bleuenn; Sørensen, Jens Ager

    2015-01-01

    In this paper, we introduce the EcoBears concept that aims to augment household appliances with functional and aesthetic features to promote their "use'' and "longevity of use'' to prevent their disposal. The EcoBears also aim to support the communication of environmental issues in the home setting....... We present our initial design and implementation of the EcoBears that consist of two bear modules (a mother and her cub). We also present our preliminary concept validations and lessons learned to be considered for future directions....

  16. Cost analysis of continuous flight auger piles construction in Egypt

    Directory of Open Access Journals (Sweden)

    Hossam E. Hosny

    2016-09-01

    Full Text Available Continuous Flight Auger (CFA piling is widely used in the Egyptian construction industry. There is a dramatic fluctuation in pricing of executing this work package within short periods as a result of unsteady changes in supply-demand equilibrium. Consequently, there is an urgent need for the use of a scientific approach in estimating construction costs. Accordingly, it is crucial to consider the different cost elements of CFA piling construction as a step to reach an accurate and realistic cost estimate to be used by contractors in tendering. This research aims to study these cost elements based on an expert judgment, site observations and statistical analysis in order to develop an effective tool to estimate the total construction cost of the CFA piles in any future project. Expert survey was performed to draw detailed information to construct a cost breakdown structure (CBS that was used as a basis for developing the proposed cost model. The developed cost model is then validated through the application on fifty two projects. Such projects were carefully selected in different sizes, purposes and locations. Then the collected data were exposed to statistical analysis techniques. An average percentage error of 4.1% was observed upon comparing the estimated costs with the actual costs of these projects. A sensitivity analysis was then performed to recognize the most effective cost factors. The developed recommended model was used by some experienced contractors in the Egyptian market who expressed their satisfaction with the model.

  17. Enhanced In-Pile Instrumentation at the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    J. Rempe; D. Knudson; J. Daw; T. Unruh; B. Chase; K. Condie

    2011-06-01

    Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility (NSUF) in 2007 to support the development and deployment of enhanced in-pile sensors. This paper reports results from this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and real-time flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted.

  18. NEET In-Pile Ultrasonic Sensor Enablement-Final Report

    Energy Technology Data Exchange (ETDEWEB)

    J. Daw; J. Rempe; J. Palmer; P. Ramuhalli; R. Montgomery; H.T. Chien; B. Tittmann; B. Reinhardt; P. Keller

    2014-09-01

    Ultrasonic technologies offer the potential to measure a range of parameters during irradiation of fuels and materials, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes under harsh irradiation test conditions. There are two primary issues that currently limit in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. The harsh nature of in-pile testing and the variety of desired measurements demand that an enhanced signal processing capability be developed to make in-pile ultrasonic sensors viable. To address these issues, the NEET ASI program funded a three year Ultrasonic Transducer Irradiation and Signal Processing Enhancements project, which is a collaborative effort between the Idaho National Laboratory, the Pacific Northwest National Laboratory, the Argonne National Laboratory, and the Pennsylvania State University. The objective of this report is to document the objectives and accomplishments from this three year project. As summarized within this document, significant work has been accomplished during this three year project.

  19. In-pile loop experiments in water chemistry and corrosion

    International Nuclear Information System (INIS)

    Kysela, J.

    1986-09-01

    Results on the study of Zr-1% Nb alloy corrosion, in out-of and in-pile loops simulating the working conditions of the VVER-440 reactor (Soviet, PWR type), covered the time period May 1982-April 1986 were reported, as well as, results on transport and filtration of corrosion products. Methods and techniques used in the study included remote measurement of corrosion rate by polarizing resistance, out-of-pile loop at the temperature 350 deg. C, pressure 19 MPa, circulation 20 kgs/h and in-pile water loop with constant flow rate 10,000 kgs/h, pressure 16 MPa, temperature 330 deg. C and neutron flux 7x10 13 n/cm 2 .s. It was shown that solid suspended particles with chemical composition corresponding most frequently to magnetite or nickelous ferrite, though with non-stoichiometric composition Me x 2+ Fe 3- x 3+ O 4 were found. Continuous filtration of water by means of electromagnetic filter leads to a decrease of radioactivity of the outer epitactic layer only. Effect of filtration on the inner topotactic layer is negligible. The corrosion rates for the above-mentioned parameters are given

  20. STABILIZATION OF A FAILED SLOPE WITH PILED STRUCTURES

    Directory of Open Access Journals (Sweden)

    M. Rifat KAHYAOĞLU

    2008-01-01

    Full Text Available Neogene aged units of a densely populated region of Western Turkey along the Aegean Sea coastline is susceptible to landslides causing frequent economic loss especially following raining seasons. Several landslides took place in the area covering a narrow band of the coastline between Izmir and Söke (Aydın. Countermeasures against these relatively small-scale slope failures in the region often involve construction of either reinforced concrete retaining walls or stabilizing piles, which can be easily constructed by local contractors. In this study borings, in-situ and laboratory soil mechanics tests, geophysical and geological investigations have been performed in order to investigate the landslide occurred in the yard of an elementary school in Söke township. The analysis of two rows of piled retaining system constructed to reuse the school building against a potential slides are presented. Three inclinometer measurements have been performed after completion of the bored pile system. It has been concluded that the measured and the calculated displacement values are both small. There is no problem of the built project by means of moments and displacements.

  1. Piloting procedure for a pile running below critical level

    International Nuclear Information System (INIS)

    Lacour, J.; Raievski, V.

    1957-01-01

    The knowledge of the subcritical state of a reactor in the course of starting up makes it possible to avoid passing too quickly through the critical state. The problem arises every time the pile is put into action again following, for example, an appreciable modification in the fuel charge, or an accidental fall of the security rods during a run at high flux or at high temperature. The method described provides a mean of knowing at each moment the anti-reactivity value of the pile by means of a direct-reading instrument mounted on the control board. This result is obtained by superimposing a fixed frequency oscillation on the normal movement of a control rod, and reading on a phase-meter the dephasing of the neutron density. Theory shows, and experiments confirm, that for a given frequency the dephasing depends only on the lifetime of the fast neutrons, the characteristics of the slow neutrons and the anti-reactivity of the pile. The minimum time necessary for an anti-reactivity determination is equal to a modulation period (from 1 to 4 seconds). (authors) [fr

  2. Impact Simulations on the Rubble Pile Asteroid (2867) Steins

    Science.gov (United States)

    Deller, Jakob; Snodgrass, Colin; Lowry, Stephen C.; Price, Mark C.; Sierks, Holger

    2014-11-01

    Images from the OSIRIS camera system on board the Rosetta spacecraft (Keller et al. 2010) has revealed several interesting features on asteroid (2867) Steins. Its macro porosity of 40%, together with the shape that looks remarkably like a YORP evolved body, both indicate a rubble pile structure. A large crater on the southern pole is evidence for collisional evolution of this rubble pile asteroid. We have developed a new approach for simulating impacts on asteroid bodies that connects formation history to their collisional evolution. This is achieved by representing the interior as a ‘rubble pile’, created from the gravitational aggregation of spherical ‘pebbles’ that represent fragments from a major disruption event. These ‘pebbles’ follow a power law size function and constitute the building blocks of the rubble pile. This allows us to explicitly model the interior of rubble pile asteroids in hyper-velocity impact simulations in a more realistic way. We present preliminary results of a study validating our approach in a large series of simulated impacts on a typical small main belt rubble pile asteroid using the Smoothed Particle Hydrodynamics solver in Autodyn. We show that this approach allows us to explicitly follow the behavior of a single ‘pebble’, while preserving the expected properties of the bulk asteroid as known from observations and experiments (Holsapple 2009). On the example of Steins, we use this model to investigate if surface features like the northern hill at 75/100 degrees lon/lat distance to the largest crater (Jorda et al. 2012), or the catena of depletion pits, can be explained by the displacement of large fragments in the interior of the asteroid during the impact. We do this by following the movement of pebbles below the surface feature in simulations that recreate the shape of the impact crater.Acknowledgements: Jakob Deller thanks the Planetary Science Institute for a Pierazzo International Student Travel Award that funds

  3. 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

  4. Fluorine lubricated bearing technology

    Science.gov (United States)

    Mallaire, F. R.

    1973-01-01

    An experimental program was conducted to evaluate and select materials for ball bearings intended for use in liquid fluorine and/or FLOX. The ability of three different ball-separator materials, each containing nickel, to form and transfer a nickel fluoride film to provide effective lubrication at the required areas of a ball bearing operating in liquid fluorine was evaluated. In addition, solid lubrication of a ball bearing operating in liquid fluorine by either a fused fluoride coating applied to all surfaces of the ball separator or by a fluoride impregnation of porous sintered material ball separators was evaluated. Less bearing wear occurred when tests were conducted in the less reactive FLOX. Bearings fabricated from any of the materials tested would have relatively short wear lives and would require frequent replacement in a reusable engine.

  5. Full-Scale Physical Modeling Of The System "Granular Media—Steel Sheet Piling"

    Science.gov (United States)

    Dubrovskyy, M. P.; Meshcheryakov, G. N.; Petrosyan, V. N.; Dubrovska, O. M.

    2011-12-01

    This paper considers the problem of determination of real parameters of the cross-sectional values of sheet piling walls made of U-profile piles (moment of inertia and section modulus) and their drivability regarding piles interaction with granular media (for example, sandy soil). Among main factors which influence on this one can mention soil friction in the interlocks and the transmission of longitudinal shear forces in the interlocks of the sheet piles. In reality granular media-interlock interaction depends mainly on installation method and properties of the granular media. Study of dependencies between applied forces and friction in the interlocks by full-scale physical modeling during press-in regarding pile-pile interaction and granular media properties was aiming to refine calculation model as well as to provide reliable numerical modeling and design of the considered system.

  6. Investigation of Redistribution of Pile Foundation Forces Under Successive Loading of Its Elements

    Science.gov (United States)

    Sedin, Vladimir; Bikus, Kateryna; Kovba, Vladislav

    2017-12-01

    Redistribution of pile foundation forces under successive loading of its elements was investigated under laboratory conditions. A segment of pile foundation model was taken for use in the case study. Load tests on the pile foundation model segment, without joining its elements (pile and plate, which turns into grillage) and based on different combinations of static loadings were conducted. This proved that the loading of a plate causes skin friction on some length of the pile side surface as well as providing additional loading and settlement. Test results have shown that application of successive elements enables the foundation to carry loads up to 13% higher than in the case of a standard pile foundation loading with the same settlement rates.

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

    International Nuclear Information System (INIS)

    Horton, H.L.

    1985-01-01

    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

  8. Numerical Estimation of the Pile Toe and Shaft Unit Resistances During the Installation Process in Sands

    Directory of Open Access Journals (Sweden)

    Konkol Jakub

    2015-03-01

    Full Text Available Numerical simulations of a pile jacking were carried out. A Coupled Eulerian-Lagrangian (CEL formulation was used to treat with large deformation problems. An Abaqus, a commercial Finite Element Method software suit, was used as a computing environment. The Mohr-Coulomb constitutive model was applied and the Coulomb model of friction was used to describe pile-soil interaction. Calculations were made for three different pile diameters. Toe and shaft unit resistances versus depth for each pile were investigated and plotted. CPT-based solutions were compared with the results of numerical simulations.

  9. Optimal Pile Arrangement for Minimizing Excess Pore Water Pressure Build-Up

    DEFF Research Database (Denmark)

    Barari, Amin; Saadati, Meysam; Ibsen, Lars Bo

    2013-01-01

    Numerical analysis of pile group in a liquefiable soil was considered to investigate the influence of pile spacing on excess pore pressure distribution and liquefaction potential. The analysis is conducted using a two-dimensional plain strain finite difference program considering a nonlinear...... constitutive model for sandy soil, strength and stiffness reduction, and pile-soil interaction. The Mohr-Coulomb constitutive model coupled with Byrne pore pressure build-up model have been employed in the analysis. Numerical analysis results show that pile groups have significant influence on the dynamic...... response of sandy soil as they reduce the amount of excess pore pressure development during seismic shaking and may even prevent liquefaction....

  10. Development of p-y curves of laterally loaded piles in cohesionless soil.

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2014-01-01

    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.

  11. 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

    This study is related to the design of anti-slide piles for several landslides in Wanzhou city located in the Three Gorges area. Due to the construction of the Three Gorges Reservoir the hydro-geological conditions in this area have deteriorated significantly, leading to larger instability problems. China has invested a lot of money in slope stabilization measures for the treatment of landslides in the Three Gorges area. One of the methods for the stabilization of large landslides is the design of anti-sliding piles. This paper focuses on extensive slope stability analysis and modeling of the mechanical behavior of the landslide masses, and the parameters required for designing the number, size and dimensions of reinforced concrete stabilization piles. The study focuses on determining the rock parameters, anchor depth, and the pile and soil interaction coefficient. The study aims to provide guidelines for anti-slide pile stabilization works for landslides in the Wanzhou area. The research work contains a number of aspects. First a study is carried out on the distribution of pressures expected on the piles, using two different methods that take into account the expected pore water pressure and seismic acceleration. For the Ercengyan landslide , the Limit Equilibrium Method and Strength Reduction Method of FEM are compared through the results of the landslide pressure distributions on the piles and stress fields in the piles. The second component is the study of the required anchor depth of antislide piles, which is carried out using a statistical analysis with data from 20 landslides that have been controlled with anti-sliding piles. The rock characteristics of the anchor locations were obtained using laboratory tests, and a classification of rock mass quality is made for the anchors of antislide piles. The relationship between the critical anchor height and the angle of the landslide slip surface is determined. Two different methods are presented for the length

  12. Comparative Model Tests of SDP and CFA Pile Groups in Non-Cohesive Soil

    Directory of Open Access Journals (Sweden)

    Krasiński Adam

    2015-02-01

    Full Text Available The research topic relates to the subject of deep foundations supported on continuous flight auger (CFA piles and screw displacement piles (SDP. The authors have decided to conduct model tests of foundations supported on the group of piles mentioned above and also the tests of the same piles working as a single. The tests are ongoing in Geotechnical Laboratory of Gdaňsk University of Technology. The description of test procedure, interpretation and analysis of the preliminary testing series results are presented in the paper.

  13. Determination Of Pile Quality Using Low Strain Integrity Testing And Automatic Signal Matching

    OpenAIRE

    Özüdoğru, Tolga Yılmaz

    2007-01-01

    Low strain pile integrity testing which utilizes one dimensional wave propagation theory makes it possible to detect major discontinuities or defects (cavities, cracks, decrease and increase in cross-section) within a pile quickly and economically. In this study, pile integrity testing data of 187 piles in two close sites located in Büyükçekmece are analyzed. The test method utilized in this project is the sonic echo method, and the test itself is specifically called the “Sonic Integrity Test...

  14. Simplified Model for the Hybrid Method to Design Stabilising Piles Placed at the Toe of Slopes

    Directory of Open Access Journals (Sweden)

    Dib M.

    2018-01-01

    Full Text Available Stabilizing precarious slopes by installing piles has become a widespread technique for landslides prevention. The design of slope-stabilizing piles by the finite element method is more accurate comparing to the conventional methods. This accuracy is because of the ability of this method to simulate complex configurations, and to analyze the soil-pile interaction effect. However, engineers prefer to use the simplified analytical techniques to design slope stabilizing piles, this is due to the high computational resources required by the finite element method. Aiming to combine the accuracy of the finite element method with simplicity of the analytical approaches, a hybrid methodology to design slope stabilizing piles was proposed in 2012. It consists of two steps; (1: an analytical estimation of the resisting force needed to stabilize the precarious slope, and (2: a numerical analysis to define the adequate pile configuration that offers the required resisting force. The hybrid method is applicable only for the analysis and the design of stabilizing piles placed in the middle of the slope, however, in certain cases like road constructions, piles are needed to be placed at the toe of the slope. Therefore, in this paper a simplified model for the hybrid method is dimensioned to analyze and design stabilizing piles placed at the toe of a precarious slope. The validation of the simplified model is presented by a comparative analysis with the full coupled finite element model.

  15. Ultra-precision bearings

    CERN Document Server

    Wardle, F

    2015-01-01

    Ultra-precision bearings can achieve extreme accuracy of rotation, making them ideal for use in numerous applications across a variety of fields, including hard disk drives, roundness measuring machines and optical scanners. Ultraprecision Bearings provides a detailed review of the different types of bearing and their properties, as well as an analysis of the factors that influence motion error, stiffness and damping. Following an introduction to basic principles of motion error, each chapter of the book is then devoted to the basic principles and properties of a specific type of bearin

  16. Steel Sheet Piles - Applications and Elementary Design Issues

    Science.gov (United States)

    Sobala, Dariusz; Rybak, Jarosław

    2017-10-01

    High-intensity housing having been carried out in town’s centres causes that many complex issues related to earthworks and foundations must be resolved. Project owners are required to ensure respective number of parking bays, which in turn demands 2-3 storeys of underground car parks. It is especially difficult to fulfil in dense buildings of old town areas where apart from engineering problems, very stringent requirements of heritage conservator supervision are also raised. The problems with ensuring stability of excavation sidewalls need to be, at the same time, dealt with analysis of foundations of neighbouring structures, and possible strengthening them at the stages of installing the excavation protection walls, progressing the excavations and constructing basement storeys. A separate problem refers to necessity of constructing underground storeys below the level of local groundwater. This requires long-term lowering of water table inside excavation while at possibly limited intervention in hydrological regime beyond the project in progress. In river valleys such “hoarding off” the excavation and cutting off groundwater leads to temporary or permanent disturbances of groundwater run-off and local swellings. Traditional way to protect vertical fault and simultaneously to cut-off groundwater inflow consists in application of steel sheet pilings. They enable to construct monolithic reinforced concrete structures of underground storeys thus ensuring both their tightness and high rigidity of foundation. Depending on situation, steel sheet pilings can be in retrieving or staying-in-place versions. This study deals with some selected aspects of engineering design and fabrication of sheet piling for deep excavations and underground parts of buildings.

  17. Clear-water scour at single piers and pile groups

    OpenAIRE

    Lança, Rui Miguel Madeira

    2013-01-01

    The major damage to bridges at river crossings occurs during floods. Damage is caused for various reasons, one of the main reasons being the riverbed scour at bridge foundations. Local scour is induced by the flow field generated around piers typically inserted in movable bed rivers. In Portugal, the tragic accident of Entre-os-Rios was mostly due to scour at one of the bridge piers. Physical and economic reasons lead to bridge foundations composed of a pier column founded on a pile cap...

  18. In-pile experimental device for Sirene thermionic converters

    International Nuclear Information System (INIS)

    Bliaux, J.; Durand, J.; Lazare-Chopard, G.

    1969-01-01

    The irradiation device described here, was built for in pile life tests of 100 We SIRENE converters. The nuclear converter is located in a sealed vacuum chamber, which is plugged at the lower end of a coaxial tubing acting as electrical leads. The output power is available on a variable resistive load on the bank of the reactor pool. Thermal, electrical and neutronic parameters of the converter are recorded. Since 1967, two permanent devices allowed five experiments in the swimming pool TRITON (CEN-FAR) and the results, obtained till now, are presented. (authors) [fr

  19. In-pile gamma spectrometry and irradiation control at Osiris

    International Nuclear Information System (INIS)

    Farny, G.; Destot, M.; Corre, J.; Texier, D.; Faugere, J.L.; Mouchnino, M.

    1975-01-01

    A new gamma spectrometry facility is available near Osiris reactor core, at Saclay. This device enables nuclear fuels to be examined in loops or capsules all along their irradiation, a few minutes being sufficient to transfer the fuel from the irradiation place to the measurement bench. So, spacelike and timelike history of a lot of fission products, especially short-lived radionuclides, can be observed. Using such in-pile spectrometry device, of original design, allows to avoid radioactive decay corrections and the risks of any information less. Performance of the device is given together with some preliminary results and their interpretation [fr

  20. Study on Computer Numerical Simulation of Driving Static Pressure Pile

    Science.gov (United States)

    Hong, Ji; Xueyi, Yu

    The method to study soil compaction effect caused by driving static pressure pile was proposed with the holes expansion principle analysis. It uses FEM (finite element method) computer numerical simulation to research holes expansion commonly. The expansion of holes radius changes from a0 to 2a0 corresponding to original one from zero to R. Comparing with conclusions obtained from other theories, FEM computer numerical simulation is valid for the analysis of holes expansion. Comparing with the traditional holes expansion principle, it expands the application scope and can be extended to analyze other cross-section forms of holes.

  1. 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...... within the clay sample by carrying out the experiments at different g fields. The findings suggest that the normalised shape of the p-y curves can be predicted within a sufficient accuracy using the current methodology but that the ultimate lat-eral resistance is underestimated at shallow depths...

  2. Investigation of the bio pile treatment for oily sludge

    Science.gov (United States)

    Bai, He; Wang, Xinxin; Chen, Yu; Cao, Xingtao; Ma, Zhengzhao; Guo, Bing; Zhao, Guangyu; Li, Chen

    2017-05-01

    With the rapid development of petro-chemical industry as well as the stricter requirement of environmental protection, the treatment of oily sludge is around the corner for the petroleum companies. A pilot experiment had been carried out in this study to investigate the changes of n-alkanes, polycyclic aromatic hydrocarbons and total petroleum hydrocarbons in the oily sludge. Results show that the oil content in the sludge decreased to 5023 mg/kg within 90 days, which provide technical support for the engineering application of bio pile treatment

  3. Investigation of Bearing Technology

    National Research Council Canada - National Science Library

    Maciag, Walter

    1998-01-01

    .... They eliminate roller needles and balls in bearings. Since the GC design does not require lubrication maintenance, there is no need for the u-joint cross to contain lubrication reservoirs and distribution channels and their input fitting...

  4. DW_BEAR

    Data.gov (United States)

    Department of Homeland Security — Subset of BEAR (Bi-Weekly Examination Analysis and Reporting) data used for financial audit remediation reporting within the Coast Guard Business Intelligence (CGBI)...

  5. Horizontal Displacement Control in Course of Lateral Loading of a Pile in a Slope

    Science.gov (United States)

    Muszyński, Zbigniew; Rybak, Jarosław

    2017-10-01

    Standard procedures concerning axial and lateral capacity testing of foundation piles usually consist of a single loading cycle. Constant load steps or constant settlement increments may be applied in the test. Such a procedure significantly differs from in-situ conditions of pile loading, which can be cyclic – especially in the case of the constructions, which are subject to wind load. Several tests were performed to observe the behaviour of the driven piles subject to fast cyclic loading in horizontal direction (lateral load). The manner in which the load tests were performed made it possible to determine the displacement of the 40×40 cm pile in the least favourable loading scheme, i.e. the lateral load capacity of the pile oriented towards the embankment slope. The piles were originally designed for the foundation of noise barriers along the highway. Some of the piles were broken in course of driving and a cautious check of their behaviour under load was requested before the assembling of the entire structure. Eight load tests were carried out altogether. While selecting the piles for further load tests, the representativeness of the random sample was taken into account. The piles with diverse cross section and length were chosen, on the basis of the previous low strain tests of their integrity. The subsoil around the piles consisted of medium and coarse sands with the density index ID>0.67. The pile heads were free. The points of support of the reference frame to which the sensors were fastened were located at the distance of 0.6 m from the side surface of the pile loaded laterally. In order to assure the independence of measurement, additional control (verifying) geodetic survey of the displacements of the piles subject to the load tests was carried out. The research conducted at Wroclaw University of Technology made it possible to collect and summarize the results of displacement measurements in course of static load testing of driven piles in a slope

  6. Gear bearing drive

    Science.gov (United States)

    Weinberg, Brian (Inventor); Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor)

    2011-01-01

    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  7. Rolling bearing analysis

    CERN Document Server

    Harris, Tedric A

    2001-01-01

    One of the most well-known experts in the field brings cutting-edge research to practitioners in the new edition of this important reference. Covers the improved mathematical calculations for rolling bearing endurance developed by the American Society of Mechanical Engineers and the Society of Lubrication and Tribology Engineers. Updated with new material on Condition-Based Maintenance, new testing methods, and new bearing materials.

  8. Load responsive hydrodynamic bearing

    Science.gov (United States)

    Kalsi, Manmohan S.; Somogyi, Dezso; Dietle, Lannie L.

    2002-01-01

    A load responsive hydrodynamic bearing is provided in the form of a thrust bearing or journal bearing for supporting, guiding and lubricating a relatively rotatable member to minimize wear thereof responsive to relative rotation under severe load. In the space between spaced relatively rotatable members and in the presence of a liquid or grease lubricant, one or more continuous ring shaped integral generally circular bearing bodies each define at least one dynamic surface and a plurality of support regions. Each of the support regions defines a static surface which is oriented in generally opposed relation with the dynamic surface for contact with one of the relatively rotatable members. A plurality of flexing regions are defined by the generally circular body of the bearing and are integral with and located between adjacent support regions. Each of the flexing regions has a first beam-like element being connected by an integral flexible hinge with one of the support regions and a second beam-like element having an integral flexible hinge connection with an adjacent support region. A least one local weakening geometry of the flexing region is located intermediate the first and second beam-like elements. In response to application of load from one of the relatively rotatable elements to the bearing, the beam-like elements and the local weakening geometry become flexed, causing the dynamic surface to deform and establish a hydrodynamic geometry for wedging lubricant into the dynamic interface.

  9. The transfer matrix method applied to steel sheet pile walls

    Science.gov (United States)

    Kort, D. A.

    2003-05-01

    This paper proposes two subgrade reaction models for the analysis of steel sheet pile walls based on the transfer matrix method. In the first model a plastic hinge is generated when the maximum moment in the retaining structure is exceeded. The second model deals with a beam with an asymmetrical cross-section that can bend in two directions.In the first part of this paper the transfer matrix method is explained on the basis of a simple example. Further the development of two computer models is described: Plaswall and Skewwall.The second part of this paper deals with an application of both models. In the application of Plaswall the effect of four current earth pressure theories to the subgrade reaction method is compared to a finite element calculation. It is shown that the earth pressure theory is of major importance on the calculation result of a sheet pile wall both with and without a plastic hinge.In the application of Skewwall the effectiveness of structural measures to reduce oblique bending is investigated. The results are compared to a 3D finite element calculation. It is shown that with simple structural measures the loss of structural resistance due to oblique bending can be reduced.

  10. UNMANNED AERIAL VEHICLE USE FOR WOOD CHIPS PILE VOLUME ESTIMATION

    Directory of Open Access Journals (Sweden)

    M. Mokroš

    2016-06-01

    Full Text Available The rapid development of unmanned aerial vehicles is a challenge for applied research. Many technologies are developed and then researcher are looking up for their application in different sectors. Therefore, we decided to verify the use of the unmanned aerial vehicle for wood chips pile monitoring. We compared the use of GNSS device and unmanned aerial vehicle for volume estimation of four wood chips piles. We used DJI Phantom 3 Professional with the built-in camera and GNSS device (geoexplorer 6000. We used Agisoft photoscan for processing photos and ArcGIS for processing points. Volumes calculated from pictures were not statistically significantly different from amounts calculated from GNSS data and high correlation between them was found (p = 0.9993. We conclude that the use of unmanned aerial vehicle instead of the GNSS device does not lead to significantly different results. Tthe data collection consumed from almost 12 to 20 times less time with the use of UAV. Additionally, UAV provides documentation trough orthomosaic.

  11. Out of pile testing of the PHWR fuel bundles

    International Nuclear Information System (INIS)

    Mahender Dev; Raghunathan, S.; Agarwal, G.K.; Patel, R.J.; Agarwal, R.G.

    2002-01-01

    In PHWRs fuel bundle resides in the form of a string in the coolant channels. These fuel bundles are required to be replaced periodically with the help of fuelling machine and spent fuel is discharged to the spent-fuel bay through fuel transfer system. During complete refuelling operation, and during residence in channel fuel bundle experiences various kinds of loads like drag force, impact force, force applied by Fuelling Machine ram and force applied by various actuators in fuel transfer system. These fuel bundles are manufactured indigenously and require out of pile testing for qualification of design as well as manufacturing process. In 220 MWe PHWRs, 19-element split spacer fuel bundle is used whereas in 500 MWe PHWRs 37-element fuel bundle will be used. A comprehensive programme was conducted to generate, basic data like estimation of loads coming on fuel bundles, experimental data generation about friction factor and pressure drop and carrying out of pile testing of 19-element fuel bundles in Integral Thermal Facility at Hall-7. The 37-element fuel bundles were tested in fuel locator test facility at simulated reactor conditions for pressure drop test, endurance test and cross flow test. The 37-element bundles have also been tested for flow-induced vibration during residence in the reactor. The paper describes the experimental techniques and setups, for simulating the reactor condition and determining the effect of those conditions on the fuel bundles. (author)

  12. In-pile Thermal Conductivity Characterization with Time Resolved Raman

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xinwei

    2018-03-19

    Executive Summary The project is designed to achieve three objectives: (1) Develop a novel time resolved Raman technology for direct measurement of fuel and cladding thermal conductivity. (2) Validate and improve the technology development by measuring ceramic materials germane to the nuclear industry. (3) Conduct instrumentation development to integrate optical fiber into our sensing system for eventual in-pile measurement. We have developed three new techniques: time-domain differential Raman (TD-Raman), frequency-resolved Raman (FR-Raman), and energy transport state-resolved Raman (ET-Raman). The TD-Raman varies the laser heating time and does simultaneous Raman thermal probing, the FR-Raman probes the material’s thermal response under periodical laser heating of different frequencies, and the ET-Raman probes the thermal response under steady and pulsed laser heating. The measurement capacity of these techniques have been fully assessed and verified by measuring micro/nanoscale materials. All these techniques do not need the data of laser absorption and absolute material temperature rise, yet still be able to measure the thermal conductivity and thermal diffusivity with unprecedented accuracy. It is expected they will have broad applications for in-pile thermal characterization of nuclear materials based on pure optical heating and sensing.

  13. Noise and pile-up in liquid sampling calorimeters

    International Nuclear Information System (INIS)

    Franzini, P.

    1988-01-01

    The design and construction of detectors for the SSC presents new challenges and requires electronics of priorly unavailable performance. Most detector elements produce minute signals which can be lost in the ever present noise from thermal fluctuation and the finite charge of the electron. The author presents in these notes a pedagogical introduction to noise and pile-up, as applicable to liquid sampling calorimeters, beginning with a brief, only descriptive, introduction to amplifiers and the physical origins of noise. He then studies the particular case of noise in charge measurements, in particular for calorimeters, where parallel noise is usually negligible. By a physical example he discusses optimal filtering, proving that gaussian filters are not optimal. The scaling laws of noise versus source capacitance and filter bandwidth or shaping time, are emphasized. An explicit example for pulse shapes peaking at 1 μs is computed and extrapolated to 0.1 μs, more appropriate for an SSC detector. Solutions for the several problems arising at short shaping times are discussed and the conditions for optimal preamp-detector matching (for minimum noise) are derived. He also briefly discusses pile-up and its scaling laws. Correlations between signal samples at different times are considered and computed for an example. Correlations are necessary to compute the noise in signals reconstructed from sampling

  14. Acoustic emission intensity analysis of corrosion in prestressed concrete piles

    Science.gov (United States)

    Vélez, William; Matta, Fabio; Ziehl, Paul

    2014-02-01

    Corrosion of steel strands in prestressed concrete (PC) bridges may lead to substantial damage or collapse well before the end of the design life. Acoustic Emission (AE) is a suitable nondestructive technique to detect and locate corrosion in reinforced and prestressed concrete, which is key to prioritize inspection and maintenance. An effective tool to analyze damage-related AE data is intensity analysis (IA), which is based on two data trends, namely Severity (average signal strength of high amplitude hits) and Historic Index (ratio of the average signal strength of the most recent hits to the average of all hits). IA criteria for corrosion assessment in PC were recently proposed based on empirical evidence from accelerated corrosion tests. In this paper, AE data from prestressed and non-prestressed concrete pile specimens exposed to salt water wet-dry cycling for over 600 days are used to analyze the relation between Severity and Historic Index and actual corrosion. Evidence of corrosion is gained from the inspection of decommissioned specimens. The selection of suitable J and K parameters for IA is discussed, and an IA chart with updated corrosion criteria for PC piles is presented.

  15. Pile driving models for the evaluation of soil penetration resistance measurements from planetary subsurface probes

    Science.gov (United States)

    Kömle, Norbert I.; Poganski, Joshua; Kargl, Günter; Grygorczuk, Jerzy

    2015-05-01

    design of future penetration devices and for the evaluation of soil-mechanical properties from measured penetration data. The most sensitive soil parameter controlling penetration progress per stroke is the ultimate static bearing capacity of the ground. Although the method used for our calculations is essentially the same as that applied by Smith (1962) for describing the behaviour of long and heavy piles in geotechnical engineering, it is found that the penetration process for such small and light weight systems takes place in a quite different way. While for the former secondary oscillations are irrelevant for the determination of the permanent set caused by one stroke, in the latter the penetration in response to one hammer stroke takes place in many small increments, until a stable depth is reached. Our model describes the full dynamic behaviour of the system over an arbitrary time span and has the potential to be adapted to systems with other geometrical dimensions and masses, as long as the diameter/length ratio of the probe remains reasonably small.

  16. Analysis Method for Laterally Loaded Pile Groups Using an Advanced Modeling of Reinforced Concrete Sections

    Directory of Open Access Journals (Sweden)

    Stefano Stacul

    2018-02-01

    Full Text Available A Boundary Element Method (BEM approach was developed for the analysis of pile groups. The proposed method includes: the non-linear behavior of the soil by a hyperbolic modulus reduction curve; the non-linear response of reinforced concrete pile sections, also taking into account the influence of tension stiffening; the influence of suction by increasing the stiffness of shallow portions of soil and modeled using the Modified Kovacs model; pile group shadowing effect, modeled using an approach similar to that proposed in the Strain Wedge Model for pile groups analyses. The proposed BEM method saves computational effort compared to more sophisticated codes such as VERSAT-P3D, PLAXIS 3D and FLAC-3D, and provides reliable results using input data from a standard site investigation. The reliability of this method was verified by comparing results from data from full scale and centrifuge tests on single piles and pile groups. A comparison is presented between measured and computed data on a laterally loaded fixed-head pile group composed by reinforced concrete bored piles. The results of the proposed method are shown to be in good agreement with those obtained in situ.

  17. Effect of heat build-up on carbon emissions in chimato compost piles ...

    African Journals Online (AJOL)

    A study was conducted to determine impacts of heat build-up of chimato compost piles TD0, TD20, TD40, TD50, TD60, TD80 and TD100, made by blending maize stalks with 0, 20, 40, 50, 60, 80 and 100% Tithonia diversifolia, respectively, on carbon losses and emissions during composting. Compost piles temperatures ...

  18. Comparison between Dynamic Responses of Hollow and Solid Piles for Offshore Wind Turbine Foundations

    DEFF Research Database (Denmark)

    Bayat, Mehdi; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    2013-01-01

    the dynamic behavior of soil and interaction between soil and piles. To avert damage to offshore foundation, it becomes necessary to identify and quantify the soil-structure interaction and the related damping effects on the system. In this study, a single pile is investigated by means of boundary integral...

  19. Testing protocol for predicting driven pile behavior within pre-bored soil : research project capsule.

    Science.gov (United States)

    2014-02-01

    The objective of this project is to compile the state-of-the-art and best practice : results available on the subject of pre-bored piles and develop a research and : instrumentation testing plan for fi eld data collection and select multiple pile : d...

  20. In-situ grouting of uranium-mill-tailings piles: an assessment

    International Nuclear Information System (INIS)

    Tamura, T.; Boegly, W.J. Jr.

    1983-05-01

    Passage in 1978 of the Uranium Mill Tailings Radiation Control Act (UMTRCA) initiated a program of remedial action for 22 existing mill tailings piles generated in the period 1940 to 1970 as part of the nation's defense and nuclear power programs. The presence of these piles poses potential health and environmental contamination concerns. Possible remedial actions proposed include multilayer covers over the piles to reduce water infiltration, reduce radon gas releases, and reduce airborne transport of tailings fines. In addition, suggested remedial actions include (1) the use of liners to prevent groundwater contamination by leachates from the piles and (2) chemical stabilization of the tailings to retain the radioactive and nonradioactive sources of contamination. Lining of the piles would normally be applicable only to piles that are to be moved from their present location such that the liner could be placed between the tailings and the groundwater. However, by using civil engineering techniques developed for grouting rocks and soils for strength and water control, it may be possible to produce an in situ liner for piles that are not to be relocated. The Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project Office requested that ORNL assess the potential application of grouting as a remedial action. This report examines the types of grouts, the equipment available, and the costs, and assesses the possibility of applying grouting technology as a remedial action alternative for uranium mill tailings piles

  1. Thermal integrity profiling for augered cast-in-place piles – implementation plan : summary.

    Science.gov (United States)

    2017-09-01

    Auger-cast-in-place (ACIP) piles are created when an auger the diameter and length of the desired pile is drilled into the ground. Concrete is pumped through the central axis of the auger as it is withdrawn, pulling up excavated soil as concrete fill...

  2. A study of the effect of driving on pre-bored piles

    Science.gov (United States)

    Mabsout, Mounir; Sadek, Salah

    2003-02-01

    A finite element model for pile-driving analysis is developed and used to investigate the behaviour of pre-bored piles, which are then driven the last 1.25 or 2.25 m to their final design depth. The study was conducted for the case of saturated clays. The model traces the penetration of the pile into the soil and accommodates for large deformations. The non-linear behaviour of the clay in this study is predicted using the bounding-surface-plasticity model, as applied to isotropic cohesive soils. The details of the 3-D numerical modelling and computational schemes are presented. A significant difference was observed in the pile displacement during driving, and in the computed soil resistance at the pile tip, particularly at the earliest driving stages. No difference in soil resistance at the soil pile interface along the pile shaft was detected between the pre-bored piles whether driven 1.25 or 2.25 m.

  3. 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 to a...

  4. Main issues of pile foundation at waterfront development and its prevention method

    Science.gov (United States)

    Manap, N.; Tan, K. Y.; Syahrom, N.

    2017-12-01

    Pile foundation is widely used in construction and building marine structures. This is because pile foundation is an important structure and should have long-term durability. However, in waterfront development, a lot of issues from the seawater should be considered distinctively because it consists of many problems that can affect the building structure especially the foundation of the building. Thus, a research should be conducted to identify issues of pile foundation at waterfront development and determine its prevention methods. The research was carried out through interviews with the developers and contractors from the projects of Lexis Hibiscus at Port Dickson, Negeri Sembilan and Redevelopment for Deep-Water Facilities at Quay 6 in Pasir Gudang, Johor, Malaysia. The objectives of this research are to identify issues of pile foundation and to determine the prevention methods of pile foundation issues at waterfront development. All respondents agreed that the main issues of pile foundations at waterfront development are the wave and tide condition. The prevention methods of the issue faced at waterfront development that are most frequently used for the pile foundation are coating system and concrete cover. This research is beneficial to all developers and contractors to ensure pile foundations at waterfront development can be protected by using the prevention methods.

  5. Effect of relative pile’s stiffness on lateral pile response under loading of large eccentricity

    DEFF Research Database (Denmark)

    Zania, Varvara; Hededal, Ole; Klinkvort, R.T.

    2015-01-01

    The wide application of monopiles as foundations for offshore wind turbines has raised the issue of the suitability of the p –y curves proposed by API for lateral pile loading, since the latter were developed after full-scale tests on flexible and slender piles. This study investigates the role o...

  6. Behavior of Skin Friction of Piles subjected to Top-downward and ...

    African Journals Online (AJOL)

    ... the different resistance of the soil-pile system. In-situ and FEM results show lower shaft resistance when the pile is subjected to base-upward compression than when it is compressed from the top. The ratio of skin friction of 0.85 is obtained, the ratio is expected to be different for different soils. Journal of Civil Engineering, ...

  7. Physical deterioration of preservative treated poles and pilings exposed to salt water

    Science.gov (United States)

    Grant T. Kirker; Jessie Glaeser; Stan T. Lebow; Frederick Green III; Carol A. Clausen

    2011-01-01

    This report details the results of laboratory analyses of wooden pilings sent to the USDA Forest Products Laboratory in March 2011. These samples were removed from coastal wooden posts, poles, piles, and deck boards. A total of 22 samples, consisting of either core borings or surface fiber samples, were removed from four installations along the South Carolina coast....

  8. Nondestructive evaluation of potential quality of creosote-treated piles removed from service

    Science.gov (United States)

    Xiping. Wang; Robert J. Ross; John R. Erickson; John W. Forsman; Gary D. McGinnis; Rodney C. De Groot

    2001-01-01

    Stress-wave-based nondestructive evaluation methods were used to evaluate the potential quality and modulus of elasticity (MOE) of wood from creosote-treated Douglas-fir and southern pine piles removed from service. Stress-wave measurements were conducted on each pile section. Stress-wave propagation speeds were obtained to estimate the MOE of the wood. Tests were then...

  9. Numerical Modelling of Large-Diameter Steel Piles at Horns Rev

    DEFF Research Database (Denmark)

    Augustesen, Anders Hust; Brødbæk, K. T.; Møller, M.

    2009-01-01

    as foundation for a wind turbine at Horns Rev located in the Danish sector of the North Sea. The outer diameter of the pile is 4 m and the subsoil at the location consists primarily of sand. The behaviour of the pile is investigated under realistic loading conditions by means of a traditional Winkler...

  10. Improving agreement between static method and dynamic formula for driven cast-in-place piles : [technical brief].

    Science.gov (United States)

    2013-08-01

    Many transportation facility structures in Wisconsin are founded on driven round, closed-end, steel, pipe piles. The piles are driven to capacity and then filled with concrete. The Wisconsin Department of Transportation (WisDOT) has designed and driv...

  11. 77 FR 55459 - Takes of Marine Mammals Incidental to Specified Activities; Piling and Fill Removal in Woodard...

    Science.gov (United States)

    2012-09-10

    ... 12- to 24-in diameter pilings, along with associated pier superstructure, will be removed near but... continuous noise, such as that produced by vibratory pile extraction, are 190 dB root mean square (rms) re: 1...

  12. Watchable Wildlife: The Black Bear

    Science.gov (United States)

    Lynn L. Rogers

    1992-01-01

    Black bears are the bears people most often encounter. Black bears live in forests over much of North America, unlike grizzlies that live only in Alaska, northern and western Canada, and the northern Rocky Mountains. This brochure presents the latest information on black bear life and how this species responds to an ever-increasing number of campers, hikers, and...

  13. Climate Drives Polar Bear Origins

    Science.gov (United States)

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

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

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo

    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...... used as foundation for modern offshore wind energy converters. The aim of the present work is to investigate the pile behaviour for non-slender piles by means of small-scale testing. The pile behaviour is investigated and compared for both static and cyclic loading. When conducting small-scale tests...... 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...

  15. Numerical Investigation on the Thermo-mechanical Behavior of a Quadratic Cross Section Pile Heat Exchanger

    DEFF Research Database (Denmark)

    Pagola, Maria Alberdi; Madsen, Søren; Jensen, Rasmus Lund

    2017-01-01

    Pile heat exchangers are traditional foundation piles with built in heat exchangers. As such, the footing of the building both serves as a structural component and a heating/cooling supply element. The existing geotechnical design standards do not consider the nature of thermo-active foundations...... and, therefore, there is a need to develop guidelines to design them properly. This paper contributes by studying the thermo-mechanical behavior of the precast piles which are 15-meter long and have a quadratic cross section and a W-shape pipe heat exchanger. This article aims to numerically assess...... the additional changes in the pile load transfer generated by its heating and cooling. In addressing this objective, a preliminary multi-physical finite element analysis is conducted which serves as a tool for exploring: i) the thermally induced mechanical stresses within the concrete and on the pile-soil axial...

  16. Settlement Analysis of Saturated Tailings Dam Treated by CFG Pile Composite Foundation

    Directory of Open Access Journals (Sweden)

    Jinxing Lai

    2016-01-01

    Full Text Available Cement fly ash gravel (CFG pile composite foundation is an effective and economic foundation treatment approach, which is significant to building foundation, subgrade construction, and so forth. The present paper aims at investigating the settlement behaviors of saturated tailings dam soft ground under CFG pile composite foundation treatment, in which FEM and laboratory model test were utilized. The proposed findings demonstrate that CFG pile treatment is effective in reinforcing saturated tailings dam and loading has little influence on settlement of soil between piles. The variation of soil between piles settlement in FEM has a good agreement with the laboratory model test. Additionally, the cushion deformation modulus has a small effect on the composite foundation settlement, although the cushion thickness will generate certain influence on the settlement distribution of the composite foundation.

  17. Evaluation of an Improved Technique for Geosynthetic-Reinforced and Pile-Supported Embankment

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2015-01-01

    Full Text Available With a large number of applications of conventional technique for geosynthetic-reinforced and pile-supported (GRPS embankment (called CT embankment, many deficiencies have been exposed. In view of the deficiencies, an improved technique, fixed-geosynthetic-reinforced and pile-supported embankment (called FGT embankment, is developed. To investigate the performance of the FGT embankment, the comparison analyses and parametric studies are conducted by Finite Element Method (FEM. The influencing factors investigated include elastic modulus of soil, tensile stiffness of geosynthetics, pile length, pile spacing, and pile elastic modulus. In addition, the cost evaluation for the FGT embankment and CT embankment is also made. The results show that the FGT embankment can significantly reduce the settlement and differential settlement, enhance the stability, and provide an economical and effective measure for the construction of high embankment at the bridge approach.

  18. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    Energy Technology Data Exchange (ETDEWEB)

    Testa, M., E-mail: marianna.testa@lnf.infn.it

    2016-07-11

    The large rate of multiple simultaneous proton–proton interactions, or pile-up, generated by the Large Hadron Collider in Run 1 required the development of many new techniques to mitigate the adverse effects of these conditions. The methods employed to correct for the impact of pile-up on jet energy, shapes and multiplicity with the ATLAS detector are presented here. They include energy correction techniques based on estimates of the average pile-up energy density and jet-to-vertex association techniques. Extensions of these methods to reduce the impact of pile-up on jet shapes use both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC are also shown.

  19. Probabilistic pseudostatic analysis of pile in laterally spreading ground: Two layer soil profile

    Directory of Open Access Journals (Sweden)

    Reda Farag

    2014-06-01

    Full Text Available Coupling the finite element model of pile under lateral spread with the Monte Carlo Simulation is frequently prohibited by excessive lengthily computations. In the present paper, a simplified pseudostatic method is integrated with an improved response surface scheme to evaluate the reliability of pile subjected to lateral spread. The pseudostatic model takes both geometric and soil nonlinearities into account, while, the response surface formulation takes; load, geometry, material and model uncertainties into consideration. First; the improved response surface scheme is suggested and validated with the help of a simple example. Then, the pseudostatic model of a full size pile under lateral spread is integrated with the improved response surface scheme in order to assess the pile reliability. In the considered example, for both operational and structural possible modes of failure, it has been found that the most influential random variables are lateral displacement, and pile radius, respectively.

  20. Dynamic soil-pile-interaction effects on eigenfrequency and damping of slender structures

    DEFF Research Database (Denmark)

    Zania, Varvara

    2014-01-01

    of the dynamic soil-pile-interaction on the natural vibration characteristics of the flexibly supported structure. For this purpose a two-step iterative procedure has been developed based on two analytical solutions. The frequency dependent dynamic stiffness and damping coefficients are taken into consideration......-conservative overestimation of the eigenfrequency and underestimation of damping especially for small slenderness ratios and high flexibility factor of the soil – pile system (short, rigid piles). The observed trends become even more prominent as the height of the slender structure increases. The effect of the monopile...... after a rigorous solution of horizontal soil – pile vibration, while the modified SSI eigenperiod and damping are calculated accounting for the cross coupling stiffness and damping terms of the soil – pile system. Disregarding the off diagonal terms is considered inappropriate since it results to non...

  1. Study of the light emitted in the moderation of a heavy-water pile

    International Nuclear Information System (INIS)

    Breton, D.

    1958-06-01

    During the running of a reactor which uses water as a neutron moderator, a bluish light is seen to appear inside the liquid. A detailed study of this radiation, undertaken on the Fontenay-aux-Roses pile, has shown that the spectrum is identical with that which characterises the light produced by the Cerenkov effect. The light intensity as a function of the pile power grows exponentially as a function of time when the pile diverges, with a lifetime equal to that of the rise in power. An examination of the various particles present in the pile has led to the conclusion that only electrons with an energy greater than 260 keV con produce the Cerenkov light. The light source thus produced is about 2.10 6 photons/cm 2 of water, when the pile power equals 1 watt. (author) [fr

  2. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    CERN Document Server

    Testa, Marianna; The ATLAS collaboration

    2015-01-01

    The large rate of multiple simultaneous proton-proton interactions, or pile-up, generated by the Large Hadron Collider in Run I required the development of many new techniques to mitigate the adverse effects of these conditions. This presentation shows the methods employed to correct for the impact of pile-up on jet energy, jet shapes, and even spurious additional jets. Energy correction techniques that incorporate sophisticated estimates of the average pile-up energy density and tracking information are described in detail. Jet-to-vertex association techniques are also presented. We also describe the extension of these techniques to ameliorate the effect of pile-up on jet shapes using both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC will be also discussed.

  3. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    CERN Document Server

    Testa, Marianna; The ATLAS collaboration

    2015-01-01

    The large rate of multiple simultaneous proton-proton interactions, or pile-up, generated by the Large Hadron Collider in Run I required the development of many new techniques to mitigate the adverse effects of these conditions. The methods employed to correct for the impact of pile-up on jet energy, shapes and multiplicity with the ATLAS detector are here presented. They include energy correction techniques based on estimates of the average pile-up energy density and jet-to-vertex association techniques. Extensions of these methods to reduce the impact of pile-up on jet shapes use both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC are also shown.

  4. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    International Nuclear Information System (INIS)

    Testa, M.

    2016-01-01

    The large rate of multiple simultaneous proton–proton interactions, or pile-up, generated by the Large Hadron Collider in Run 1 required the development of many new techniques to mitigate the adverse effects of these conditions. The methods employed to correct for the impact of pile-up on jet energy, shapes and multiplicity with the ATLAS detector are presented here. They include energy correction techniques based on estimates of the average pile-up energy density and jet-to-vertex association techniques. Extensions of these methods to reduce the impact of pile-up on jet shapes use both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC are also shown.

  5. Numerical Simulation by using Soldiers Pile of the Embankment on Semarang-Solo Highway

    Science.gov (United States)

    Tumanduk, M. S. S. S.; Maki, T. S.; Pangkey, T. U. Y.; Pandeiroth, Y. C.

    2018-02-01

    Semarang-Solo highway works section II Gedawang-Penggaron constitutes a labile area. It is thought to be effect of the existence of coat clay shale which have moulded. For the purpose of anticipating the embankment mass movement it is placed line bored pile and stringed up (soldiers pile). The objective of this research is to know the efficient use of soldier’s pile of the embankment on Semarang-Solo highway section II Gedawang-Penggaron pursuant based upon numerical simulation. The result of analysis depicts that original slope in a stabil state with horizontal displacement which equal to 0.06 m and safety factor (SF) which equal to 1.31. The strengthened embankment with bored pile is not effective to give am SF improvement at slope so that, at this phase, the slope cannot be slid to be safe enough from landslide namely with horizontal displacement which equal to 0.20 m and SF which equal to 1.09. The effect of traffic load horizontal displacement is which equal to 0.21 m with SF which equal to 1.00. The earthquake simulation results horizontal displacement which equal to 0.75 m with SF which equal to 1.00. Long variation of bored pile of phase II by neglecting bored pile phase III at the depth 35 m yields horizontal displacement which equal to 0.03 m and SF optimum which equal to 2.17. The variation of pile location by placing bored pile under embankment slope foot with distance from the location of bored pile of phase II which equal to 20 m without changing the profile of the existing bored pile creates the horizontal displacement which equals to 0.02 m with SF which equal to 2.29. The result of the horizontal displacement and SF of the two alternative is safer compared to the existing condition (SF>1.5).

  6. Assessing the Extent of Sediment Contamination Around Creosote-treated Pilings Through Chemical and Biological Analyses

    Science.gov (United States)

    Stefansson, E. S.

    2008-12-01

    Creosote is a common wood preservative used to treat marine structures, such as docks and bulkheads. Treated dock pilings continually leach polycyclic aromatic hydrocarbons (PAHs) and other creosote compounds into the surrounding water and sediment. Over time, these compounds can accumulate in marine sediments, reaching much greater concentrations than those in seawater. The purpose of this study was to assess the extent of creosote contamination in sediments, at a series of distances from treated pilings. Three pilings were randomly selected from a railroad trestle in Fidalgo Bay, WA and sediment samples were collected at four distances from each: 0 meters, 0.5 meters, 1 meter, and 2 meters. Samples were used to conduct two bioassays: an amphipod bioassay (Rhepoxynius abronius) and a sand dollar embryo bioassay. Grain size and PAH content (using a fluorometric method) were also measured. Five samples in the amphipod bioassay showed significantly lower effective survival than the reference sediment. These consisted of samples closest to the piling at 0 and 0.5 meters. One 0 m sample in the sand dollar embryo bioassay also showed a significantly lower percentage of normal embryos than the reference sediment. Overall, results strongly suggest that creosote-contaminated sediments, particularly those closest to treated pilings, can negatively affect both amphipods and echinoderm embryos. Although chemical data were somewhat ambiguous, 0 m samples had the highest levels of PAHs, which corresponded to the lowest average survival in both bioassays. Relatively high levels of PAHs were found as far as 2 meters away from pilings. Therefore, we cannot say how far chemical contamination can spread from creosote-treated pilings, and at what distance this contamination can still affect marine organisms. These results, as well as future research, are essential to the success of proposed piling removal projects. In addition to creosote-treated pilings, contaminated sediments must

  7. Acoustic dose-behavioral response relationship in sea bass (Dicentrarchus labrax) exposed to playbacks of pile driving sounds

    NARCIS (Netherlands)

    Kastelein, Ronald A.; Jennings, Nancy; Kommeren, Aimée; Helder-Hoek, Lean; Schop, Jessica

    2017-01-01

    The foundations of offshore wind turbines are attached to the sea bed by percussion pile driving. Pile driving sounds may affect the behavior of fish. Acoustic dose-behavioral response relationships were determined for sea bass in a pool exposed for 20 min to pile driving sounds at seven mean

  8. 76 FR 51947 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in the Columbia...

    Science.gov (United States)

    2011-08-19

    ... the Columbia River. The facility would allow shipping of potash (salts containing potassium in water... piles and removal of 177 wood piles. Because elevated sound levels from pile driving have the potential... handling equipment, storage structures, utilities, and internal access roads on the site, a marine berth...

  9. Effects of Diameter on Initial Stiffness of P-Y Curves for Large-Diameter Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo; Augustesen, Anders Hust

    2010-01-01

    -pile interaction. Hence, a modified expression for the p-y curves for statically loaded piles in sand is proposed in which the initial slope of the p-y curves depends on the depth below the soil surface, the pile diameter and the internal angle of friction. The evaluation is based on three-dimensional numerical...

  10. Radial Halbach Magnetic Bearings

    Science.gov (United States)

    Eichenberg, Dennis J.; Gallo, Christopher A.; Thompson, William K.

    2009-01-01

    Radial Halbach magnetic bearings have been investigated as part of an effort to develop increasingly reliable noncontact bearings for future high-speed rotary machines that may be used in such applications as aircraft, industrial, and land-vehicle power systems and in some medical and scientific instrumentation systems. Radial Halbach magnetic bearings are based on the same principle as that of axial Halbach magnetic bearings, differing in geometry as the names of these two types of bearings suggest. Both radial and axial Halbach magnetic bearings are passive in the sense that unlike most other magnetic bearings that have been developed in recent years, they effect stable magnetic levitation without need for complex active control. Axial Halbach magnetic bearings were described in Axial Halbach Magnetic Bearings (LEW-18066-1), NASA Tech Briefs, Vol. 32, No. 7 (July 2008), page 85. In the remainder of this article, the description of the principle of operation from the cited prior article is recapitulated and updated to incorporate the present radial geometry. In simplest terms, the basic principle of levitation in an axial or radial Halbach magnetic bearing is that of the repulsive electromagnetic force between (1) a moving permanent magnet and (2) an electric current induced in a stationary electrical conductor by the motion of the magnetic field. An axial or radial Halbach bearing includes multiple permanent magnets arranged in a Halbach array ("Halbach array" is defined below) in a rotor and multiple conductors in the form of wire coils in a stator, all arranged so the rotary motion produces an axial or radial repulsion that is sufficient to levitate the rotor. A basic Halbach array (see Figure 1) consists of a row of permanent magnets, each oriented so that its magnetic field is at a right angle to that of the adjacent magnet, and the right-angle turns are sequenced so as to maximize the magnitude of the magnetic flux density on one side of the row while

  11. Quantification of sodium pentobarbital residues from equine mortality compost piles.

    Science.gov (United States)

    Payne, J; Farris, R; Parker, G; Bonhotal, J; Schwarz, M

    2015-04-01

    Sodium pentobarbital, a euthanasia drug, can persist in animal carcasses following euthanasia and can cause secondary toxicosis to animals that consume the remains. This experiment was conducted to observe the effects of composting on euthanized horse carcass degradation and sodium pentobarbital residues in compost material up to 367 d. Six separate compost bins were constructed on pastureland. Three bins served as the control while 3 served as the treatment. The carbonaceous material, or bulking agent, consisted of hardwood chips mixed with yard waste wetted to approximately 50% moisture content. Bulking agent was added to each bin at a depth of 0.46 m, creating the pad. A licensed veterinarian provided 6 horse carcasses for use in the experiment. These horses had required euthanasia for health reasons. All horses were weighed and then sedated with an intravenous injection of 8 mL of xylazine. After sedation the 3 horses in the treatment group were euthanized by intravenous injection of 60 mL of sodium pentobarbital. The 3 control group horses were anesthetized by intravenous injection of 15 mL of ketamine hydrochloride and then humanely euthanized by precise gunshot to the temporal lobe. Following euthanasia, each carcass was placed on the center of the pad and surrounded with 0.6 m of additional bulking agent. Serum and liver samples were obtained immediately following death. Compost samples were obtained on d 7, 14, 28, 56, 84, 129, 233, and 367 while soil samples were obtained on d -1 and 367. Each sample was analyzed for sodium pentobarbital concentration. Compost pile and ambient temperatures were also recorded. Composting successfully degraded soft tissue with only large bones remaining. Data illustrate that sodium pentobarbital was detectable up to 367 d in compost piles with no clear trend of concentration reduction. Drug residues were detected in soil samples indicating that sodium pentobarbital leached from the carcass and through the pad. These

  12. Evidence for the incorporation of lead into barite from waste rock pile materials

    Energy Technology Data Exchange (ETDEWEB)

    COURTIN-NOMADE, ALEXANDRA; SOUBRAND-COLIN, MARILYNE; MARCUS, MATTHEW A.; FAKRA, SIRINE .C

    2008-01-21

    Because Pb is one of the most toxic elements and is found as a major contaminant in mining environments, this study aims to identify the distribution of this element in host phases issued from the alteration of mine wastes. The sampling location was a former mine near Oakland, California (USA). This mine was once a source of sulfide minerals from which sulfuric acid was made. The material discussed in this paper was collected in iron hardpans that were formed within the waste rock pile resulting from the excavation work. In most contaminated environments (soils, mine waste), secondary metal-bearing phases arising from alteration processes are usually fine-grained (from 10 {micro}m to less than 1 {micro}m) and highly heterogeneous, requiring the use of micron-scale techniques. We performed micro-Raman spectroscopy, microscanning X-ray diffraction (SXRD), and microextended X-ray near edge spectroscopy (XANES) to determine the relationships between Pb and a Ba/Fe-rich host phase. Micro-Raman spectroscopy suggests that Pb is preferentially incorporated into barite rather than goethite. Results from micro-Raman experiments show the high sensitivity of this analytical tool to the incorporation of Pb into barite by being especially sensitive to the variations of the S-O bond and showing the characteristic bands due to the contribution of Pb. This association is confirmed and is well-illustrated by micro-SXRD mineral species maps showing the correlation between Pb and barite. Microfocused XANES indicates that Pb is present as Pb{sup 2+}, agreeing with the in situ physicochemical parameters.

  13. Out-of-pile fatigue tests on Zircaloy CANDU sheaths

    International Nuclear Information System (INIS)

    Roth, Maria; Ciocanescu, Marin; Gheorghiu, Constantin; Pitigoi, Vasile; Ducu, Catalin; Malinovschi, Viorel

    2005-01-01

    The paper outlines the achievements in the nuclear research field of cooperation on Nuclear Fuel performed as part of the collaboration under the Memorandum of Understanding, settled between Atomic Energy of Canada Limited (AECL) and Institute for Nuclear Research (ICN), The sheath behavior was simulated using out-of-pile fatigue tests, in conditions identical with those met during the operation in power cycling of CANDU reactor, except for irradiation. A special test rig, designed and carried-out at ICN ensured the experimental requirements according to the Canadian testing procedure. The description of the experimental setup and monitoring of testing parameters were also done. The fatigue life time, expressed as number of cycles to rupture (N), was measured as a function of the total strain amplitude (e) induced in the Zircaloy-4 sheath samples. Strain-Life time fatigue dependence (e-N) under low cycle fatigue conditions was also verified using the Coffin-Manson correlation. (authors)

  14. Supercritical water loop for in-pile materials testing

    Energy Technology Data Exchange (ETDEWEB)

    Ruzickova, M.; Vsolak, R.; Hajek, P.; Zychova, M.; Fukac, R. [Research Centre Rez Ltd., Husinec-Rez (Czech Republic)

    2011-07-01

    The Supercritical Water Loop (SCWL) has been designed and built within the HPLWR Phase 2 project, with the objective of testing materials under supercritical water conditions and radiation. The design parameters are set to 25MPa and 600{sup o}C in the testing area, where material samples shall be located. The loop has recently undergone pressure and leakage tests, during which the strength and tightness of the loop were proved. The loop has been also subjected to the first trial operation at nearly maximum operating parameters (temperature 550 {sup o}C was reached); loop operation was steady during several days. Presently, loop operation is envisaged in order to test the loop's long term operation ability. Samples of a material that needs further testing under out- of-pile conditions shall be exposed in the loop; the choice shall be made in agreement with the results of the WP4 - Materials of the HPLWR Phase 2 project. (author)

  15. Large deformation finite element analysis of undrained pile installation

    Science.gov (United States)

    Konkol, Jakub; Bałachowski, Lech

    2016-03-01

    In this paper, a numerical undrained analysis of pile jacking into the subsoil using Abaqus software suit has been presented. Two different approaches, including traditional Finite Element Method (FEM) and Arbitrary Lagrangian-Eulerian (ALE) formulation, were tested. In the first method, the soil was modelled as a two-phase medium and effective stress analysis was performed. In the second one (ALE), a single-phase medium was assumed and total stress analysis was carried out. The fitting between effective stress parameters and total stress parameters has been presented and both solutions have been compared. The results, discussion and verification of numerical analyzes have been introduced. Possible applications and limitations of large deformation modelling techniques have been explained.

  16. Large deformation finite element analysis of undrained pile installation

    Directory of Open Access Journals (Sweden)

    Konkol Jakub

    2016-03-01

    Full Text Available In this paper, a numerical undrained analysis of pile jacking into the subsoil using Abaqus software suit has been presented. Two different approaches, including traditional Finite Element Method (FEM and Arbitrary Lagrangian–Eulerian (ALE formulation, were tested. In the first method, the soil was modelled as a two-phase medium and effective stress analysis was performed. In the second one (ALE, a single-phase medium was assumed and total stress analysis was carried out. The fitting between effective stress parameters and total stress parameters has been presented and both solutions have been compared. The results, discussion and verification of numerical analyzes have been introduced. Possible applications and limitations of large deformation modelling techniques have been explained.

  17. Electrochemical reduction of water. Development of a flat cell pile

    International Nuclear Information System (INIS)

    Viguie, J.C.

    1978-01-01

    The working conditions of an electrolyser are described. Great variations of water vapor concentrations through the battery makes us advocate for piling up flat cells working under a constant potential. A 50 cm 2 half cathodic cell has been fabricated. The solid electrolyte is made of zirconia (0,91 ZrO 2 , 0,09 Y 2 O 3 ) associated with an embedded layer of nickel powder as the cathode. The disc is supported by an honeycomb shaped ceramic which is covered by a layer of nickel. The most promising method for solid electrolyte fabrication is the powder compaction and sintering process. The plasma jet projection gave interesting results and can be considered as an alternative process. A test set working at 850 0 C is on the way. It will give informations on the stability of the prepared parts and allow us to measure the characteristics of the planar cell [fr

  18. Analytical investigation of pile-soil interaction in sand under axial and lateral loads

    Science.gov (United States)

    Abdel-Mohti, Ahmed; Khodair, Yasser

    2014-03-01

    This paper presents a numerical study of pile-soil interaction due to application of axial and lateral loads to piles in sand. The pile-soil interaction was analyzed using the finite difference (FD) software LPILE and two finite element (FE) software. The three-dimensional (3D) FE models of pile-soil interaction have been created using Abaqus/Cae and SAP2000. Various types of soft soil were studied, such as loose, medium, and dense sand. A lateral displacement of 2 cm was applied to the top of the pile while maintaining a zero slope in a guided fixation. A combined lateral and axial load of 300 kN was also studied. The paper compared between the bending moments and lateral displacements along the depth of the pile obtained from the FD solutions and FE analyses. A parametric study was conducted to study the effect of crucial design parameters such as the modulus of elasticity of soil and the number of nonlinear soil springs that can be used to model the soil. A good agreement between the results obtained by the FE models and the FD solution was observed. Also, the FE models were capable of predicting the pile-soil interaction for all types of soft soil.

  19. Hybrid superconductor magnet bearings

    Science.gov (United States)

    Chu, Wei-Kan

    1995-01-01

    Hybrid superconductor magnet bearings (HSMB's) utilize high temperature superconductors (HTS's) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS's, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, we present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  20. Heat transfer in gas-cooled piles; Echanges thermiques dans les piles a gaz

    Energy Technology Data Exchange (ETDEWEB)

    Le Foll, J.; Gelin, P.; Robert, E. de [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Measurements under steady flow conditions gave the distribution of the local heat transfer coefficient along the cross section perimeter of a longitudinally finned can. The distribution is generally affected by strong irregularities which make the elementary theory of heat transfer along the fins inapplicable. We studied systematically the above mentioned distribution and established however that heat transfer properties were rendered similar to those of an annular channel cross-section with isotherms heat exchange perimeter by application of two non-dimensional parameters. These parameters may be calculated by integration on the specific channel cross section and will generally permit to reach a sufficient approximation. Although the computation is rather difficult the evaluation of the parameters is more easily done by electrical analogy measurements and there even exits a possibility to learn directly about the effect of slight changes of the can outer perimeter. Now, the channel as a whole is rated to such performances as are apt to keep the can temperature below a given limiting value, generally by making the assumption that the properties of the cross section remain identical through-out the channel. Usually, however, there are many separate fuel elements along the channel and consequently flux and heat transfer coefficient distribution and local temperature values on the can may be significantly disturbed compared to the simpler case above mentioned. We must therefore bear in mind to design the fuel elements to avoid end caps becoming in turn overheated. Moreover, fuel end caps may be more heavily stressed than the other parts of the can which results in a lower value of the temperature limit and it must be remembered they lie nearer fuel hotter parts on the rod axis, precisely where fuel discontinuity, to make matters worse, may cause the flux to show a rise. The flux rise was computed on an electronic machine and subsequently measured directly

  1. Multivariate adaptive regression splines and neural network models for prediction of pile drivability

    Directory of Open Access Journals (Sweden)

    Wengang Zhang

    2016-01-01

    Full Text Available Piles are long, slender structural elements used to transfer the loads from the superstructure through weak strata onto stiffer soils or rocks. For driven piles, the impact of the piling hammer induces compression and tension stresses in the piles. Hence, an important design consideration is to check that the strength of the pile is sufficient to resist the stresses caused by the impact of the pile hammer. Due to its complexity, pile drivability lacks a precise analytical solution with regard to the phenomena involved. In situations where measured data or numerical hypothetical results are available, neural networks stand out in mapping the nonlinear interactions and relationships between the system's predictors and dependent responses. In addition, unlike most computational tools, no mathematical relationship assumption between the dependent and independent variables has to be made. Nevertheless, neural networks have been criticized for their long trial-and-error training process since the optimal configuration is not known a priori. This paper investigates the use of a fairly simple nonparametric regression algorithm known as multivariate adaptive regression splines (MARS, as an alternative to neural networks, to approximate the relationship between the inputs and dependent response, and to mathematically interpret the relationship between the various parameters. In this paper, the Back propagation neural network (BPNN and MARS models are developed for assessing pile drivability in relation to the prediction of the Maximum compressive stresses (MCS, Maximum tensile stresses (MTS, and Blow per foot (BPF. A database of more than four thousand piles is utilized for model development and comparative performance between BPNN and MARS predictions.

  2. Geochemistry and toxicity of a large slag pile and its drainage complex in Sudbury, Ontario.

    Science.gov (United States)

    Souter, Laura; Watmough, Shaun A

    2017-12-15

    Slag piles from mining activities are common worldwide, but in contrast to mine tailings the environmental impact of runoff from slag piles is less documented. This study was designed to assess the geochemistry and potential toxicity of water draining a large, 62.2ha slag pile in Sudbury, Ontario. The Coniston slag pile contains 12-20Mt of slag from smelting local Ni-Cu ore between 1913 and 1972. Slag leaching experiments confirmed slag is a source of sulphate (SO 4 ), heavy metals (including Fe, Al, Ni, Co, Cu, Zn, Pb, Cr, Mn) and base cations (Ca, K, Mg, Na). Concentrations of some metals draining through slag in column experiments were similar to concentrations measured at the base of the slag pile, although base cations, SO 4 and pH were much higher, possibly because of water inputs interacting with the surrounding basic glaciolacustrine landscape. The high pH rapidly precipitates metals, leading to high accumulations in surface sediments in the pond-wetland complex draining from the pile. Away from the pile's base, vegetation cover increases, which increases dissolved organic carbon (DOC) and nutrient concentrations in runoff along with metals with strong binding affinities (e.g. Cu). Total metal concentration in water and sediment exceed provincial guidelines, particularly near the slag pile, however WHAM7 modeling indicated the free metal ion concentration in water is very low. Nevertheless, 48-h toxicity experiments showed that water with greater concentrations of solutes collected close to the slag negatively impacts D. magna, suggesting water draining the slag pile can adversely impact biota in nearby drainage areas. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2014-01-01

    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. PMID:24574932

  4. Pile-up and defective pulse rejection by pulse shape discrimination in surface barrier detectors

    International Nuclear Information System (INIS)

    Sjoeland, K.A.; Kristiansson, P.

    1994-01-01

    A technique to reject pile-up pulses and defective tail pulses from surface barrier detectors by the use of pulse shape discrimination is demonstrated. The electronic implementation of the pulse shape discrimination is based upon the zero crossing technique and for data reduction multiparameter techniques are used. The characteristic τ value for pile-up rejection is shown to be less than 56 ns. Its effect on detection limits from tail reduction in Particle Elastic Scattering Analysis (PESA) and pile-up peak suppression is discussed. ((orig.))

  5. Case Study of CPT-based Design Methods for Axial Capacity of Driven Piles in Sand

    DEFF Research Database (Denmark)

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

    2012-01-01

    . Thus, several CPT-based methods have been proposed for the design of offshore driven piles in cohesionless soil such as the UWA-05, ICP-05, and NGI-99 methods. This article treats a case study where the API-method as well as the UWA-05 and NGI-99 methods are compared using CPT-data from an offshore...... loaded offshore driven piles in cohesionless soil has until now been the β-method given in API. The API-method is based on the effective overburden pressure at the depth in question. Previous studies show deviations between full-scale load test measurements of the axial pile capacity and the predictions...

  6. Comparing heat flow models for interpretation of precast quadratic pile heat exchanger thermal response tests

    DEFF Research Database (Denmark)

    Alberdi Pagola, Maria; Poulsen, Søren Erbs; Loveridge, Fleur

    2018-01-01

    This paper investigates the applicability of currently available analytical, empirical and numerical heat flow models for interpreting thermal response tests (TRT) of quadratic cross section precast pile heat exchangers. A 3D finite element model (FEM) is utilised for interpreting five TRTs...... by inverse modelling. The calibrated estimates of soil and concrete thermal conductivity are consistent with independent laboratory measurements. Due to the computational cost of inverting the 3D model, simpler models are utilised in additional calibrations. Interpretations based on semi-empirical pile G-functions...... the potential of applying TRTs for sizing quadratic, precast pile heat exchanger foundations....

  7. Environment Impact Analysis of Shield Passing Alongside Bridge Pile Platform Using Three Dimensional Numerical Simulation

    Science.gov (United States)

    Shang, Yanliang; Shi, Wenjun; Han, Tongyin; Qin, Zhichao; Du, Shouji

    2017-10-01

    The shield method has many advantages in the construction of urban subway, and has become the preferred method for the construction of urban subway tunnel. Taking Shijiazhuang metro line 3 (administrative center station - garden park station interval) Passing alongside bridge as the engineering background, double shield crossing the bridge pile foundation model was set up. The deformation and internal force of the pile foundation during the construction of the shield were analyzed. Pile stress caused by shield construction increases, but the maximum stress is less than the design strength; the maximum surface settlement caused by the construction of 10.2 mm, the results meet the requirements of construction.

  8. Treating jet correlations in high pile-up at hadron colliders

    Directory of Open Access Journals (Sweden)

    F. Hautmann

    2016-03-01

    Full Text Available Experiments in the high-luminosity runs at the Large Hadron Collider face the challenges of very large pile-up. Primary techniques to deal with this are based on precise vertex and track reconstruction. Outside tracker acceptances, however, lie regions of interest for many aspects of the LHC physics program. We explore complementary approaches to pile-up treatment and propose a data-driven jet-mixing method which can be used outside tracker acceptances without depending on Monte Carlo generators. The method can be applied to treat correlation observables and take into account, besides the jet transverse momentum pedestal, effects of hard jets from pile-up.

  9. Beam parameters observations during the second high pile-up collisions fill in 2011

    CERN Document Server

    Trad, G; Buffat, X; Calaga, R; Cornelis, K; Herr, W; Jacquet, D; Papotti, G; Schaumann, M; Venturini Delsolaro, W

    2012-01-01

    On the 25th of October 2011, a physics fill( Fill nr 2252) was dedicated to providing ATLAS & CMS with high pile-up collisions. A peak pile-up (number of inelastic interactions per crossing) μ of almost 35 was achieved. Part of the test was also to bring the pile-up to values < 0.5 and this was achieved by separating the beams in steps. The Head-On collisions were restored after each IP separation to study its effects. In this note observations of the beam parameters evolution (bunch current, emittances and length) are presented. Some conclusions are drawn and suggestions for future MDs are discussed.

  10. Compliant hydrodynamic fluid journal bearing

    Science.gov (United States)

    Warren, E. L. (Inventor)

    1985-01-01

    An air bearing structure is described that prevents destructive bending moments within the top foil. Welds are eliminated by mounting the top bearing foil in the bearing cartridge sleeve without using a space block. Tabs or pins at the end of the top bearing foil are restrained by slots or stops formed in the cartridge sleeve. These structural members are free to move in a direction normal to the shaft while being restrained from movement in the direction of shaft rotation.

  11. Magnetic bearing and motor

    Science.gov (United States)

    Studer, Philip A. (Inventor)

    1983-01-01

    A magnetic bearing assembly (10) has an intermediate rotatable section (33) having an outer cylindrical member (30) coaxially suspended by a torsion wire (72) around an axially polarized cylindrical magnet (32). Axial alignment between the pole faces (40-43) of the intermediate section (33) and end surfaces (50-53) of opposed end bells (20, 22) provides a path of least reluctance across intervening air gaps (60-63) for the magnetic flux emanating from magnet (32). Radial dislocation increases the reluctance and creates a radial restoring force. Substitution of radially polarized magnets 107 fixed to a magnetically permeable cylinder (32') and insertion of pairs of armature coil windings (109-112) between the cylinder pair (33') provides an integral magnetic bearing and torsion motor (100) able to provide arcuately limited rotational drive.

  12. Passive magnetic bearing system

    Science.gov (United States)

    Post, Richard F.

    2014-09-02

    An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

  13. Government Risk-Bearing

    CERN Document Server

    1993-01-01

    The u.s. government bulks large in the nation's financial markets. The huge volume of government-issued and -sponsored debt affects the pricing and volume ofprivate debt and, consequently, resource allocation between competing alternatives. What is often not fully appreciated is the substantial influence the federal government wields overresource allocation through its provisionofcreditandrisk-bearing services to the private economy. Because peopleand firms generally seekto avoid risk, atsomeprice they are willing to pay another party to assume the risk they would otherwise face. Insurance companies are a class of private-sector firms one commonly thinks of as providing these services. As the federal government has expanded its presence in the U.S. economy during this century, it has increasingly developed programs aimed at bearing risks that the private sector either would not take on at any price, or would take on but atapricethoughtto besogreatthatmostpotentialbeneficiarieswouldnotpurchase the coverage. To...

  14. COMPOSITION OF BLACK BEAR MILK.

    Science.gov (United States)

    An analysis of black bear ( Ursus americanus Pallas) milk showed that the total solids, fat and protein were much higher and the lactose lower than...either cow or human milk. In comparison with polar bear (Thalarcotos maritimus ), the black bear milk was lower in fat, protein and total calories. (Author)

  15. Frictionless Bearing Uses Permanent Magnets

    Science.gov (United States)

    1965-01-01

    The purpose of this innovation was to develop a frictionless bearing for high speed, light load applications. The device involves the incorporation of permanent magnets in the bearing design. The repulsion of like magnetic poles provides concentric support of the inner member so that no metallic contact occurs between the bearing surfaces.

  16. Rotating plug bearing and seal

    International Nuclear Information System (INIS)

    Wade, E.E.

    1977-01-01

    Disclosed is a bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing. 19 claims, 3 figures

  17. Radium bearing waste disposal

    International Nuclear Information System (INIS)

    Tope, W.G.; Nixon, D.A.; Smith, M.L.; Stone, T.J.; Vogel, R.A.; Schofield, W.D.

    1995-01-01

    Fernald radium bearing ore residue waste, stored within Silos 1 and 2 (K-65) and Silo 3, will be vitrified for disposal at the Nevada Test Site (NTS). A comprehensive, parametric evaluation of waste form, packaging, and transportation alternatives was completed to identify the most cost-effective approach. The impacts of waste loading, waste form, regulatory requirements, NTS waste acceptance criteria, as-low-as-reasonably-achievable principles, and material handling costs were factored into the recommended approach

  18. Vertical Equilibrium of Sheet Pile Walls with Emphasis on Toe Capacity and Plugging

    DEFF Research Database (Denmark)

    Iversen, Kirsten Malte; Augustesen, Anders Hust; Nielsen, Benjaminn Nordahl

    Constructions including retaining walls are normally established in areas where it is impossible to conduct an excavation with inclined sides. Due to large excavation depths and due to restrictions on the deformations of the wall, it is often necessary to anchor the wall. The limited space makes...... at the pile toe to fulfil vertical equilibrium. The paper describes a case study of sheet pile walls in Aalborg Clay, and the amount of loads transferred as point loads at the pile toe for free and anchored walls is estimated. A parametric study is made for the free wall with regards to the height...... and the roughness of the wall. Due to limitations of the calculation method, the study of the anchored wall only includes variation of the roughness. For the case study, it is found that the vertical equilibrium is fulfilled for the considered free wall. An anchored wall needs a plug forming at the pile toe...

  19. The application of dynamic replacement method in deviation rectification of support pile

    Science.gov (United States)

    Peng, Congwen

    2017-04-01

    The dynamic replacement method is appled widely to the soft soil treatment, but is seldom used in retificating pile deviation. By the ways of dynamic replacement method gravel block can form underground, the gravel block can be treated as reaction-froce base, the magnitude of squeeze force needed for retificating pile deviation is related to the scale of gravel block. Take a sheet pile retaining wall for instance, the treatment scheme and paramters calculating method for deviation rectification of support pile was put forward. The project case demonstrate that this method is effective when the layout of gravel column is reasonable to a certain degree, it is a good reference to similar projects.

  20. Seismic assessment of WSDOT bridges with prestressed hollow core piles : part II.

    Science.gov (United States)

    2009-12-01

    This report investigates the seismic performance of a reinforced concrete : bridge with prestressed hollow core piles. Both nonlinear static and nonlinear dynamic : analyses were carried out. A three-dimensional spine model of the bridge was : ...

  1. Analytical Approach for Load Capacity of Large Diameter Bored Piles Using Field Data

    Directory of Open Access Journals (Sweden)

    Alaa Dawood Salman

    2015-08-01

    Full Text Available An analytical approach based on field data was used to determine the strength capacity of large diameter bored type piles. Also the deformations and settlements were evaluated for both vertical and lateral loadings. The analytical predictions are compared to field data obtained from a proto-type test pile used at Tharthar –Tigris canal Bridge. They were found to be with acceptable agreement of 12% deviation. Following ASTM standards D1143M-07e1,2010, a test schedule of five loading cycles were proposed for vertical loads and series of cyclic loads to simulate horizontal loading .The load test results and analytical data of 1.95m in diameter test pile proved efficiently to carry a working load of 450 tons. The calculated lateral displacements based on a specified coefficient of subgrade reaction are compared to the measured values from dial gauges and strain gauges placed at various locations along the length of the pile.

  2. Numerical Evaluation of Forces on Piled Bridge Foundations in Laterally Spreading Soil

    Science.gov (United States)

    2017-04-01

    The response of piled bridge foundations to liquefaction-induced lateral soil deformation is an important design consideration in seismically active regions. Recent research and case history data suggest that three-dimensional deformation of the appr...

  3. Observations on the electronic equipment employed for making measurements on the pile G1

    International Nuclear Information System (INIS)

    Ailloud, J.; Belin, P.; Meunier, A.; Tarabella, A.

    1957-01-01

    The electronic apparatus employed during the manipulations carried out on the pile G1 is briefly described, with the aim of putting on record the inconveniences encountered in the course of the operation of this equipment. (author) [fr

  4. Numerical analysis of energy piles under different boundary conditions and thermal loading cycles

    Directory of Open Access Journals (Sweden)

    Khosravi Ali

    2016-01-01

    Full Text Available The thermo- mechanical behavior of energy piles has been studied extensively in recent years. In the present study, a numerical model was adapted to study the effect of various parameters (e.g. heating/cooling temperature, head loading condition and soil stiffness on the thermo-mechanical behavior of an energy pile installed in unsaturated sandstone. The results from the simulations were compared with measurements from a thermal response test on a prototype energy pile installed beneath a 1-story building at the US Air Force Academy (USAFA in Colorado Springs, CO. A good agreement was achieved between the results obtained from the prototype and the numerical models. A parametric evaluation were also carried out which indicated the significance of the stiffness of the unsaturated sandstone and pile’s head loading condition on stress-strain response of the energy pile during heating/cooling cycles.

  5. Durability of precast prestressed concrete piles in marine environment : reinforcement corrosion and mitigation - Part 1.

    Science.gov (United States)

    2011-06-01

    Research conducted in Part 1 has verified that precast prestressed concrete piles in : Georgias marine environment are deteriorating. The concrete is subjected to sulfate and : biological attack and the prestressed and nonprestressed reinforcement...

  6. Durability of precast prestressed concrete piles in marine environment, part 2. Volume 1 : concrete.

    Science.gov (United States)

    2012-06-01

    The overall purpose of this research was to determine methods which may be applied : economically to mitigate corrosion of reinforcement in precast prestressed concrete piles in : Georgias marine environments. The research was divided into two par...

  7. Studies on carbon FRP (CFRP) prestressed concrete bridge columns and piles in marine environment.

    Science.gov (United States)

    1998-11-01

    The main objective of this study was to investigate the feasibility of using concrete piles pretensioned with Carbon Fiber Reinforced Plastics (CFRP) tendons. The study reviews the available literature on mechanical properties of CFRP reinforcement, ...

  8. Evaluation of Pile Response Due to Liquefaction - Induced Lateral Spreading of the Ground

    Science.gov (United States)

    1996-07-01

    This paper reports a cooperative project between teams at Rensselaer Polytechnic Institute (RPI) and Cornell University to evaluate the effect of lateral spreading on pile foundations. Centrifuge tests of lateral spreading and the corresponding perma...

  9. Pulse pile-up in nuclear particle detection systems with rapidly varying counting rates

    International Nuclear Information System (INIS)

    Datlowe, D.W.

    1977-01-01

    Pulse pile-up in nuclear particle detection systems is the distortion of the measured pulse height distribution which occurs when there is a significant probability that more than one particle will arrive within the detector resolving time. This paper treats the problem in cases where the probability of pile-up varies on a time scale comparable to the rise time of the detector system electronics. These variations introduce structure into the pulse height distributions which cannot occur for a time-independent pile-up probability. Three classes of problems which exemplify these effects are as follows: 1) Pile-up rejection circuits. 2) Cascaded nuclear decays, in which the lifetime for emission of a second X-ray is comparable to the detector rise time. 3) Bursts of particles where the intensity is modulated on a time scale comparable to the detector rise time. These problems are solved computationally by an extension of a numerical technique previously developed. (Auth.)

  10. Effects of Pile Driving on the Residency and Movement of Tagged Reef Fish.

    Directory of Open Access Journals (Sweden)

    Joseph D Iafrate

    Full Text Available The potential effects of pile driving on fish populations and commercial fisheries have received significant attention given the prevalence of pile driving occurring in coastal habitats throughout the world. Behavioral impacts of sound generated from these activities on fish typically have a greater area of influence than physical injury, and may therefore adversely affect a greater portion of the local population. This study used acoustic telemetry to assess the movement, residency, and survival of 15 sheepshead (Archosargus probatocephalus and 10 grey snapper (Lutjanus griseus in Port Canaveral, Florida, USA, in response to 35 days of pile driving at a wharf complex. No obvious signs of mortality or injury to tagged fish were evident from the data. Received sound pressure levels from pile strikes on the interior of the wharf, where reef fish primarily occur, were on average 152-157 dB re 1 μPa (peak. No significant decrease in sheepshead daytime residency was observed during pile driving within the central portion of the wharf and area of highest sound exposure, and no major indicators of displacement from the exposure wharf with the onset of pile driving were observed. There was evidence of potential displacement from the exposure wharf that coincided with the start of pile driving observed for 2 out of 4 grey snapper, along with a decrease in daytime residency for a subset of this species with high site fidelity prior to the event. Results indicate that snapper may be more likely to depart an area of pile driving disturbance more readily than sheepshead, but were less at risk for behavioral impact given the lower site fidelity of this species.

  11. Seismic Soil-Pile Interaction Considering Nonlinear Soil Column Behavior in Saturated and Dry Soil Conditions

    OpenAIRE

    Mohammad Moeini; Mehrdad Ghyabi; Kiarash Mohtasham Dolatshahi

    2017-01-01

    This paper investigates seismic soil-pile interaction using the Beam on Nonlinear Winkler Foundation (BNWF) approach. Three soil types are considered to cover all the possible responses, as well as nonlinear site response analysis using finite element method in OpenSees platform. Excitations at each elevation that are output of the site response analysis are used as the input excitation to the soil pile system implementing multi-support excitation method. Spectral intensities of acceleration ...

  12. Anomalous Scaling Behaviors in a Rice-Pile Model with Two Different Driving Mechanisms

    International Nuclear Information System (INIS)

    Zhang Duanming; Sun Hongzhang; Li Zhihua; Pan Guijun; Yu Boming; Li Rui; Yin Yanping

    2005-01-01

    The moment analysis is applied to perform large scale simulations of the rice-pile model. We find that this model shows different scaling behavior depending on the driving mechanism used. With the noisy driving, the rice-pile model violates the finite-size scaling hypothesis, whereas, with fixed driving, it shows well defined avalanche exponents and displays good finite size scaling behavior for the avalanche size and time duration distributions.

  13. A new modelling approach for piled and other ground heat exchanger applications

    OpenAIRE

    Cecinato, F; Loveridge, F; Gajo, A; Powrie, W

    2015-01-01

    Pile heat exchangers have an increasing role to play in the delivery of renewable heating and cooling energy. Traditionally the thermal design of ground heat exchangers has relied upon analytical approaches which take a relatively simple approach to the inside of the heat exchanger. This approach is justified while the heat exchanger diameter remains small. However, as larger diameter piled founda-tions are used as heat exchangers, the transient heat transfer processes operating within the pi...

  14. Similitude Conditions Modeling Geosynthetic-Reinforced Piled Embankments Using FEM and FDM Techniques

    OpenAIRE

    Jennings, Keith; Naughton, Patrick J.

    2012-01-01

    The numerical modelling of geosynthetic-reinforced piled embankments using both the finite element method (FEM) and finite difference method (FDM) are compared. Plaxis 2D (FEM) was utilized to replicate FLAC (FDM) analysis originally presented by Han and Gabr on a unit cell axisymmetric model within a geosynthetic reinforced piled embankment (GRPE). The FEM and FED techniques were found to be in reasonable agreement, in both characteristic trend and absolute value. FEM consistently replicated...

  15. The Method of Calculating the Settlement of Weak Ground Strengthened with the Reinforced Sandy Piles

    Directory of Open Access Journals (Sweden)

    Maltseva Tatyana

    2016-01-01

    Full Text Available The paper presents an engineering method for calculating the weak clay base, strengthened with sandy piles reinforced along the contour. The method is based on the principle of layer-by-layer summation, which is used when designing the bases and foundations. The novelty of the suggested method lies in the taking account of the soil reaction along the pile lateral surface and the impact of external vertical loads on the vertical displacement of the base.

  16. Bearing for liquid metal pump

    International Nuclear Information System (INIS)

    Dickinson, R.J.; Pennell, W.E.; Wasko, J.

    1984-01-01

    A liquid metal pump bearing support comprises a series of tangentially oriented spokes that connect the bearing cylinder to the pump internals structure. The spokes may be arranged in a plurality of planes extending from the bearing cylinder to the pump internals with the spokes in one plane being arranged alternately with those in the next plane. The bearing support structure provides the pump with sufficient lateral support for the bearing structure together with the capability of accommodating differential thermal expansion without adversely affecting pump performance

  17. Bearing, gearing, and lubrication technology

    Science.gov (United States)

    Anderson, W. J.

    1978-01-01

    Results of selected NASA research programs on rolling-element and fluid-film bearings, gears, and elastohydrodynamic lubrication are reported. Advances in rolling-element bearing material technology, which have resulted in a significant improvement in fatigue life, and which make possible new applications for rolling bearings, are discussed. Research on whirl-resistant, fluid-film bearings, suitable for very high-speed applications, is discussed. An improved method for predicting gear pitting life is reported. An improved formula for calculating the thickness of elastohydrodynamic films (the existence of which help to define the operating regime of concentrated contact mechanisms such as bearings, gears, and cams) is described.

  18. Response of a pile group behind quay wall to liquefaction-induced lateral spreading: a shake-table investigation

    Science.gov (United States)

    Tang, Liang; Zhang, Xiaoyu; Ling, Xianzhang; Su, Lei; Liu, Chunhui

    2014-12-01

    The response of pile foundations near a quay wall under liquefaction-induced lateral spreading remains a complex problem. This study presents the results of a shake-table test on a 2×2 pile group behind a sheet-pile quay wall that was subjected to lateral spreading. The quay wall was employed to trigger liquefaction-induced large lateral ground deformation. The discussions focus on the behavior of the pile and the soil and on the bending moment distributions within the group pile and the restoring force characteristics at the superstructure. Overall, the piles exhibited apparent pinning effects that reduced soil deformation. In addition, the rear-row piles near the quay wall experienced larger bending moments than did the front-row piles, indicating significant pile group effects. The tests showed that lateral spreading could be a primary cause of larger monotonic deformations and bending moments. It can also be concluded that the monotonic bending moments were significantly decreased due to the presence of slow soil flow. The stiffness at the superstructure was reduced because of accumulated excess pore pressure before liquefaction, and it was recovered during lateral spreading. The present study further enhances current understanding of the behavior of low-cap pile foundations under lateral spreading.

  19. Modelling temperature-dependent heat production over decades in High Arctic coal waste rock piles

    DEFF Research Database (Denmark)

    Hollesen, Jørgen; Elberling, Bo; Jansson, P.E.

    2011-01-01

    .5–32.5 °C lower and that the pile would have been frozen 12–27 years earlier if the pile had been initially saturated with water, constructed with a thickness half of the original or a combination of both. Simulation show that the pile thickness and waste rock pyrite content are important factors......Subsurface heat production from oxidation of pyrite is an important process that may increase subsurface temperatures within coal waste rock piles and increase the release of acid mine drainage, AMD. Waste rock piles in the Arctic are especially vulnerable to changes in subsurface temperatures...... as the release of AMD normally is limited by permafrost. Here we show that temperatures within a 20 year old heat-producing waste rock pile in Svalbard (78°N) can be modelled by the one-dimensional heat and water flow model (CoupModel) with a new temperature-dependent heat-production module that includes both...

  20. Investigation of pile foundations of nuclear power plants with help of non linear analyses

    International Nuclear Information System (INIS)

    Diaz, B.E.; Schulz, M.; Costa, E.; Vaz, L.E.

    1984-01-01

    A few important 1300 MW PWR nuclear power plants have been built over pile foundations. The design requirements of Nuclear Power Plants prescribe accurate investigation of the as built conditions of the foundation. This study must take into account the actual concrete strength existent among and along the pile shafts of the foundation. In order to simulate the structural response of the foundation up to the failure, a non linear analysis must be performed. In this paper the required computer analysis procedures will be described. It can be verified that the redistribution of the internal forces in this highly hyperstatic soil-structure system can be of two types. The total applied forces over the foundation are redistributed among the piles and for each pile itself a local redistribution of forces takes place along the pile shaft. This type of analysis allows an accurate investigation of the actual safety margin existent in the pile foundation, based on the actual as built conditions of the construction. (Author) [pt

  1. Behavioral responses of a harbor porpoise (Phocoena phocoena) to playbacks of broadband pile driving sounds.

    Science.gov (United States)

    Kastelein, Ronald A; van Heerden, Dorianne; Gransier, Robin; Hoek, Lean

    2013-12-01

    The high under-water sound pressure levels (SPLs) produced during pile driving to build offshore wind turbines may affect harbor porpoises. To estimate the discomfort threshold of pile driving sounds, a porpoise in a quiet pool was exposed to playbacks (46 strikes/min) at five SPLs (6 dB steps: 130-154 dB re 1 μPa). The spectrum of the impulsive sound resembled the spectrum of pile driving sound at tens of kilometers from the pile driving location in shallow water such as that found in the North Sea. The animal's behavior during test and baseline periods was compared. At and above a received broadband SPL of 136 dB re 1 μPa [zero-peak sound pressure level: 151 dB re 1 μPa; t90: 126 ms; sound exposure level of a single strike (SELss): 127 dB re 1 μPa(2) s] the porpoise's respiration rate increased in response to the pile driving sounds. At higher levels, he also jumped out of the water more often. Wild porpoises are expected to move tens of kilometers away from offshore pile driving locations; response distances will vary with context, the sounds' source level, parameters influencing sound propagation, and background noise levels. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Element soil behaviour during pile installation simulated by 2D-DEM

    Science.gov (United States)

    Ji, Xiaohui; Cheng, Yi Pik; Liu, Junwei

    2017-06-01

    The estimation of the skin friction of onshore or offshore piles in sand is still a difficult problem for geotechnical engineers. It has been accepted by many researchers that the mechanism of driving piles in the soil has shared some similarities with that of an element shear test under the constant normal stiffness (CNS) condition. This paper describes the behaviour of an element of soil next to a pile during the process of pile penetration into dense fine sand using the 2D-DEM numerical simulation software. A new CNS servo was added to the horizontal boundary while maintaining the vertical stress constant. This should simulate the soil in a similar manner to that of a CNS pile-soil interface shear test, but allowing the vertical stress to remain constant which is more realistic to the field situation. Shear behaviours observed in these simulations were very similar to the results from previous researchers' lab shearing tests. With the normal stress and shear stress obtained from the virtual models, the friction angle and the shaft friction factor β mentioned in the API-2007 offshore pile design guideline were calculated and compared with the API recommended values.

  3. Element soil behaviour during pile installation simulated by 2D-DEM

    Directory of Open Access Journals (Sweden)

    Ji Xiaohui

    2017-01-01

    Full Text Available The estimation of the skin friction of onshore or offshore piles in sand is still a difficult problem for geotechnical engineers. It has been accepted by many researchers that the mechanism of driving piles in the soil has shared some similarities with that of an element shear test under the constant normal stiffness (CNS condition. This paper describes the behaviour of an element of soil next to a pile during the process of pile penetration into dense fine sand using the 2D-DEM numerical simulation software. A new CNS servo was added to the horizontal boundary while maintaining the vertical stress constant. This should simulate the soil in a similar manner to that of a CNS pile-soil interface shear test, but allowing the vertical stress to remain constant which is more realistic to the field situation. Shear behaviours observed in these simulations were very similar to the results from previous researchers’ lab shearing tests. With the normal stress and shear stress obtained from the virtual models, the friction angle and the shaft friction factor β mentioned in the API-2007 offshore pile design guideline were calculated and compared with the API recommended values.

  4. Laboratory and field study of the performance of helical piles in sandy soil

    Directory of Open Access Journals (Sweden)

    Farhad Nabizadeh

    2016-12-01

    Full Text Available Developing different method in construction of deep footing plays a major role in optimized and economized performing of civil projects especially in problematic soils. One of the common types of deep footing is helical piles which have several advantages such as fast procedure, useful in different soil types, performing without noise and vibration, effective in pressure and tension and etc. In this paper, the performance of 1-helix & 2-helixes and 3-helixes in an un-grouted and grouted with the field and laboratory studies are discussed. Field studies include of helical piles behavior in sand. Laboratory tests with physical FCV modeling is also carried out on the soil of the site. Grouting effect on helical piles resistance is evaluated. Comparison load test results with analytical method were compared. Results show that performance cylindrical in sandy soils in helical piles is not suitable and increasing helical number pile capacity is decreases. Also, after grouting helical pile with three helixes increases more resistant compare to one helix and double helixes.

  5. Static nonlinear analysis of piles cap based on the Continuum Damage Mechanics

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Farani de Souza

    2015-10-01

    Full Text Available The piles cap is an important structural element whose function is to transfer the actions of the superstructure for a group of piles. The visual inspection of the piles cap behavior under service conditions is not possible and, in addition, the knowledge of its actual structural performance is a vital necessity for the constructions overall stability. In this paper, a two-dimensional nonlinear analysis is carried out, by means of Finite Element Method, of a reinforced concrete pile caps with two piles found in the literature. It adopts for the material concrete a constitutive model based on the Continuum Damage Mechanics, with the possibility to provide a tensile and compression differentiated behavior. The steel is described by an elastoplastic bilinear model. The equilibrium path is achieved by Arc Length iteration technique in association with the Newton - Raphson Method. The numerical results obtained with the developed computational code are compared with the available experimental and numerical results and the analytical solution, and have the objective of evaluate the potential of the proposed modeling as an investigation numerical tool to determine the rupture force and the damage distribution in the piles cap.

  6. Design and Preparation of Carbon Based Composite Phase Change Material for Energy Piles.

    Science.gov (United States)

    Yang, Haibin; Memon, Shazim Ali; Bao, Xiaohua; Cui, Hongzhi; Li, Dongxu

    2017-04-07

    Energy piles-A fairly new renewable energy concept-Use a ground heat exchanger (GHE) in the foundation piles to supply heating and cooling loads to the supported building. Applying phase change materials (PCMs) to piles can help in maintaining a stable temperature within the piles and can then influence the axial load acting on the piles. In this study, two kinds of carbon-based composite PCMs (expanded graphite-based PCM and graphite nanoplatelet-based PCM) were prepared by vacuum impregnation for potential application in energy piles. Thereafter, a systematic study was performed and different characterization tests were carried out on two composite PCMs. The composite PCMs retained up to 93.1% of paraffin and were chemically compatible, thermally stable and reliable. The latent heat of the composite PCM was up to 152.8 J/g while the compressive strength of cement paste containing 10 wt % GNP-PCM was found to be 37 MPa. Hence, the developed composite PCM has potential for thermal energy storage applications.

  7. Bearing construction for refrigeration compresssor

    Science.gov (United States)

    Middleton, Marc G.; Nelson, Richard T.

    1988-01-01

    A hermetic refrigeration compressor has a cylinder block and a crankshaft rotatable about a vertical axis to reciprocate a piston in a cylinder on the cylinder block. A separate bearing housing is secured to the central portion of the cylinder block and extends vertically along the crankshaft, where it carries a pair of roller bearings to journal the crankshaft. The crankshaft has a radially extending flange which is journaled by a thrust-type roller bearing above the bearing housing to absorb the vertical forces on the crankshaft so that all three of the roller bearings are between the crankshaft and the bearing housing to maintain and control the close tolerances required by such bearings.

  8. 77 FR 70423 - Black Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC...

    Science.gov (United States)

    2012-11-26

    ... Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC; Notice of..., 2012, Black Bear Hydro Partners, LLC, sole licensee (transferor) and Black Bear Development Holdings, LLC and Black Bear SO, LLC (transferees) filed an application for the partial the transfer of licenses...

  9. Advanced In-pile Instrumentation for Material and Test Reactors

    International Nuclear Information System (INIS)

    Rempe, J.L.; Knudson, D.L.; Daw, J.E.; Unruh, T.C.; Chase, B.M.; Davis, K.L.; Palmer, A.J.; Schley, R.S.

    2013-06-01

    The US Department of Energy sponsors the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) program to promote U.S. research in nuclear science and technology. By attracting new research users - universities, laboratories, and industry - the ATR NSUF facilitates basic and applied nuclear research and development, advancing U.S. energy security needs. A key component of the ATR NSUF effort is to design, develop, and deploy new in-pile instrumentation techniques that are capable of providing real-time measurements of key parameters during irradiation. This paper describes the strategy developed by the Idaho National Laboratory (INL) for identifying instrumentation needed for ATR irradiation tests and the program initiated to obtain these sensors. New sensors developed from this effort are identified; and the progress of other development efforts is summarized. As reported in this paper, INL staff is currently involved in several tasks to deploy real-time length and flux detection sensors, and efforts have been initiated to develop a crack growth test rig. Tasks evaluating 'advanced' technologies, such as fiber-optics based length detection and ultrasonic thermometers are also underway. In addition, specialized sensors for real-time detection of temperature and thermal conductivity are not only being provided to NSUF reactors, but are also being provided to several international test reactors. (authors)

  10. Charge Pricing Optimization Model for Private Charging Piles in Beijing

    Directory of Open Access Journals (Sweden)

    Xingping Zhang

    2017-11-01

    Full Text Available This paper develops a charge pricing model for private charging piles (PCPs by considering the environmental and economic effects of private electric vehicle (PEV charging energy sources and the impact of PCP charging load on the total load. This model simulates users’ responses to different combinations of peak-valley prices based on the charging power of PCPs and user charging transfer rate. According to the regional power structure, it calculates the real-time coal consumption, carbon dioxide emissions reduction, and power generation costs of PEVs on the power generation side. The empirical results demonstrate that the proposed peak-valley time-of-use charging price can not only minimize the peak-valley difference of the total load but also improve the environmental effects of PEVs and the economic income of the power system. The sensitivity analysis shows that the load-shifting effect of PCPs will be more obvious when magnifying the number of PEVs by using the proposed charging price. The case study indicates that the proposed peak, average, and valley price in Beijing should be 1.8, 1, and 0.4 yuan/kWh, which can promote the large-scale adoption of PEVs.

  11. Early corrosion monitoring of prestressed concrete piles using acoustic emission

    Science.gov (United States)

    Vélez, William; Matta, Fabio; Ziehl, Paul H.

    2013-04-01

    The depassivation and corrosion of bonded prestressing steel strands in concrete bridge members may lead to major damage or collapse before visual inspections uncover evident signs of damage, and well before the end of the design life. Recognizing corrosion in its early stage is desirable to plan and prioritize remediation strategies. The Acoustic Emission (AE) technique is a rational means to develop structural health monitoring and prognosis systems for the early detection and location of corrosion in concrete. Compelling features are the sensitivity to events related to micro- and macrodamage, non-intrusiveness, and suitability for remote and wireless applications. There is little understanding of the correlation between AE and the morphology and extent of early damage on the steel surface. In this paper, the evidence collected from prestressed concrete (PC) specimens that are exposed to salt water is discussed vis-à-vis AE data from continuous monitoring. The specimens consist of PC strips that are subjected to wet/dry salt water cycles, representing portions of bridge piles that are exposed to tidal action. Evidence collected from the specimens includes: (a) values of half-cell potential and linear polarization resistance to recognize active corrosion in its early stage; and (b) scanning electron microscopy micrographs of steel areas from two specimens that were decommissioned once the electrochemical measurements indicated a high probability of active corrosion. These results are used to evaluate the AE activity resulting from early corrosion.

  12. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    The development of offshore wind turbines has been in rapid growth since the construction of the first offshore wind farm in 1991 at Vindeby, Denmark. Developing from 11 turbines at a water depth of 2-6 m each with a capacity of 450 kW to the latest farms with up to 175 turbines each with a capac......The development of offshore wind turbines has been in rapid growth since the construction of the first offshore wind farm in 1991 at Vindeby, Denmark. Developing from 11 turbines at a water depth of 2-6 m each with a capacity of 450 kW to the latest farms with up to 175 turbines each...... with a capacity of 3.6 MW and placed at water depths beyond 25 m. Different foundation solutions have over the years been applied for offshore turbines, but monopiles are currently the most applied foundation type and are typically with a pile diameter of 4-6 m and applied up to a water depth of 25 m....... The expected development of offshore wind farms is towards larger farms, larger turbines and larger water depths. Monopiles have been applied widely and it is of interest to investigate the possibilities to further optimize the design and in particular the modelling of the soil-structure interaction...

  13. Viscoelastic modelling of Zircaloy cladding in-pile transient creep

    Energy Technology Data Exchange (ETDEWEB)

    Tulkki, Ville, E-mail: ville.tulkki@vtt.fi; Ikonen, Timo

    2015-02-15

    In fuel behaviour modelling accurate description of the cladding stress response is important for both operational and safety considerations. The cladding creep determines in part the width of the gas gap, the duration to pellet-cladding contact and the stresses to the cladding due to the pellet expansion. Conventionally the strain hardening rule has been used to describe the creep response to transient loads in engineering applications. However, it has been well documented that the strain hardening rule does not describe well results of tests with load drops or reversals. In our earlier work we have developed a model for primary creep which can be used to simulate the in- and out-of-pile creep tests. Since then several creep experiments have entered into public domain. In this paper we develop the model formulation based on the theory of viscoelasticity, and show that this model can reproduce the new experimental results. We also show that the creep strain recovery encountered in experimental measurements can be explained by viscoelastic behaviour.

  14. Introgressive hybridization: brown bears as vectors for polar bear alleles.

    Science.gov (United States)

    Hailer, Frank

    2015-03-01

    The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of Molecular Ecology, Cahill et al. (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof (ABC) Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male-biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the ABC Island population in which an Alaskan brown bear served as a putatively admixture-free reference, Cahill et al. (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach. © 2015 John Wiley & Sons Ltd.

  15. STUDY ON THE REASONABLE EVALUATION OF SOIL PROPERTIES APPLIED IN THE DESIGN OF SHINSO FOUNDATION (JAPANESE STYLE CAISSON TYPE PILE) ON THE SLOPE

    Science.gov (United States)

    Yasuzato, Toshinori; Samizo, Junichi; Maeda, Yoshito; Abe, Tetsuo; Matsuki, Satoshi; Okutani, Junpei

    The objective of this study is to find ways to maximize the design economy of the shinso foundation (Japanese style caisson type pile) on the rock slope through an evaluation of strength properties of the rock before and after plasticity. We investigate the influence of soil properties on the design result by carrying out experiments which give the soil properties before and after plasticity and by doing parametric studies on the soil properties. Experiment using small-scale shinso foundation is performed to verify the validity of result of examinations. Comparison between the experiment and the analytical result reveals the bearing capacity characteristics of the shinso foundation on the slope and gives new insights on the more economical design of the shinso foundation.

  16. Study of technology of pile foundation construction of no.5 main pier of Shoujiang bridge in Wenchuan County

    Science.gov (United States)

    Huang, Xianbin; Liu, Chenyang; Chen, Chunyang; Wangren, Yahong; Xu, Jialin; Xian, Jin

    2018-03-01

    The group of pile foundation of no.5 pier in Shoujiang Bridge needs to overcome the big load of large span continuous steel structure. The length of single pile foundation is 77m and the diameter of single pile foundation is 250cm. It not only faces the flood in the upstream of Shoujiang river, the construction obstacles during summer rain period, but also the reservoir clearance activity of Zipingpu reservoir and the high water level in winter and other water level fluctuation that have huge impact on platform of pile foundation construction. This article introduces the preparation in aspect of personnel, material, equipment and so on of pile foundation construction, and also conduct intensive research on leveling the field, assaying pile location, the embedment of the steel casing, installing the drill, mixing mud, drilling, final hole inspection and clearance, steel cage construction, perfusing concrete under water.

  17. Displacement effects of pile driving during offshore wind farm construction on harbour porpoises (Phocoena Phocoena)

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, Miriam; Diederichs, Ansgar; Wollheim, Laura; Betke, Klaus; Nehls, Georg

    2011-07-01

    Full text: Noise emissions from pile driving during offshore wind farm construction may injure marine mammals in the vicinity and cause large-scale disturbance and habitat displacement. So far little is known about the responses of marine mammals to such noise emissions making it difficult to predict possible impacts on their population and conservation status. We investigated spatial and temporal responses of harbour porpoises to pile driving during construction of 92 mono-pile foundations in the Danish North Sea in 2008 and of 6 tripod and 6 jacket foundations in the German North Sea in 2009. We used passive acoustic monitoring devices that record harbour porpoise echolocation clicks (T-PODs), which were deployed at different distances from the construction site. Noise levels during pile driving were measured at various distances. We found a clear impact of pile driving on the recordings of harbour porpoises, which stayed below average normal levels for up to 72 hours after pile driving in the near vicinity. A negative impact could be detected out to a distance of about 18 km, while at 22 km no negative effect was found. Here porpoise recordings temporarily increased. This shows that effects of wind farm construction reach over considerable distances and last much longer than previously assumed. We further found some differences between the effects of the different types of construction, possibly linked to the varying pile driving durations that were necessary. These results should be considered for future spatial and temporal planning of offshore wind farm constructions. Suitable mitigation measures should be adopted to reduce such far and long reaching effects on harbour porpoises and possibly other marine mammals. (Author)

  18. Computational design of rolling bearings

    CERN Document Server

    Nguyen-Schäfer, Hung

    2016-01-01

    This book comprehensively presents the computational design of rolling bearings dealing with many interdisciplinary difficult working fields. They encompass elastohydrodynamics (EHD), Hertzian contact theory, oil-film thickness in elastohydrodynamic lubrication (EHL), bearing dynamics, tribology of surface textures, fatigue failure mechanisms, fatigue lifetimes of rolling bearings and lubricating greases, Weibull distribution, rotor balancing, and airborne noises (NVH) in the rolling bearings. Furthermore, the readers are provided with hands-on essential formulas based on the up-to-date DIN ISO norms and helpful examples for computational design of rolling bearings. The topics are intended for undergraduate and graduate students in mechanical and material engineering, research scientists, and practicing engineers who want to understand the interactions between these working fields and to know how to design the rolling bearings for automotive industry and many other industries.

  19. Three-dimensional finite element nonlinear dynamic analysis of pile groups for lateral transient and seismic excitations

    International Nuclear Information System (INIS)

    Maheshwari, B.K.; Truman, K.Z.; El Naggar, M.H.; Gould, P.L.

    2004-01-01

    The effects of material nonlinearity of soil and separation at the soil-pile interface on the dynamic behaviour of a single pile and pile groups are investigated. An advanced plasticity-based soil model, hierarchical single surface (HiSS), is incorporated in the finite element formulation. To simulate radiation effects, proper boundary conditions are used. The model and algorithm are verified with analytical results that are available for elastic and elastoplastic soil models. Analyses are performed for seismic excitation and for the load applied on the pile cap. For seismic analysis, both harmonic and transient excitations are considered. For loading on the pile cap, dynamic stiffness of the soil-pile system is derived and the effect of nonlinearity is investigated. The effects of spacing between piles are investigated, and it was found that the effect of soil nonlinearity on the seismic response is very much dependent on the frequency of excitation. For the loading on a pile cap, the nonlinearity increases the response for most of the frequencies of excitation while decreasing the dynamic stiffness of the soil-pile system. (author)

  20. Grease lubrication in rolling bearings

    CERN Document Server

    Lugt, Piet M

    2012-01-01

    The definitive book on the science of grease lubrication for roller and needle bearings in industrial and vehicle engineering. Grease Lubrication in Rolling Bearings provides an overview of the existing knowledge on the various aspects of grease lubrication (including lubrication systems) and the state of the art models that exist today. The book reviews the physical and chemical aspects of grease lubrication, primarily directed towards lubrication of rolling bearings. The first part of the book covers grease composition, properties and rheology, including thermal

  1. Improvement of bearing support lubrication

    Directory of Open Access Journals (Sweden)

    Shehovtseva E. V.

    2016-12-01

    Full Text Available Gas turbine engine bearing supports is an important part in providing product efficiency of general and special-purpose engineering industry. Attempts are being made to increase efficiency of bearing support. Such attempts are caused by the modern tendency of the development of engineering striving for compact machines and units possessing increased reliability and durability. Researches on finding discrepancies in operation of support for this purpose have been executed. The reasons of occurrence the fatigue crumbling on external bearing races at different stages development of working surface damage have been investigated. The basic constructions of support of shaft for the aviation gas turbine engine and methods of their lubrication have been considered. Shortcomings of existing methods of lubrication of bearing supports have been marked. The upgraded construction of the module of gas turbine bearing shaft, which allows to improve conditions of lubrication and bearing cooling as a result of a uniform oil feed to the contact zones of outside bearing race and rolling elements and forced oil removal from contact zones of inside bearing race and rolling elements has been suggested. The task of improving conditions of lubrication supply to an internal holder of the bearing has been solved. The developed design allows applying unconventional methods of lubrication and cooling of a bearing support. Thus it is recommended to use process of regulation of a microrough on working surfaces bearing support during grinding-in. It will allow to improve a stage grinding-in and to increase reliability and durability of bearing support.

  2. Hydrostatic and hybrid bearing design

    CERN Document Server

    Rowe, W B

    1983-01-01

    Hydrostatic and Hybrid Bearing Design is a 15-chapter book that focuses on the bearing design and testing. This book first describes the application of hydrostatic bearings, as well as the device pressure, flow, force, power, and temperature. Subsequent chapters discuss the load and flow rate of thrust pads; circuit design, flow control, load, and stiffness; and the basis of the design procedures and selection of tolerances. The specific types of bearings, their design, dynamics, and experimental methods and testing are also shown. This book will be very valuable to students of engineering des

  3. Synergism Analysis of Bedding Slope with Piles and Anchor Cable Support under Sine Wave Vehicle Load

    Directory of Open Access Journals (Sweden)

    Li Dan-Feng

    2016-01-01

    Full Text Available Slope instability under dynamic load is the technical difficulty in the engineering; the evaluation of slope stability under dynamic load and the control of dynamic load is particularly important. In this paper, taking the right side slope of K27+140 m~380 m typical section (K27 slope for short in Chongqing Fuling-Fengdu-Shizhu expresses highway as an example to calculate and analyze. The K27 slope is under sinusoidal vehicle load and supported by anchor cable and antislide pile to resist downslide strength; at the same time, the combined effect of them is studied. Three-dimensional finite element methodology (FEM is used to simulate the bedding slope with piles and anchor cable support; furthermore, the eigenvalue can be obtained. In order to reduce error of the elastic boundary conditions caused by the reflection effect of wavelengths, the combination of Lysmer surface viscous boundary and traditional ground support boundaries is utilized to analyze and calculate the time-histories during bedding slope under dynamic load. The dynamic response of pile anchor support to resist sliding force is obtained. The concept of the pile anchor supporting coordinate interval is put forward. Furthermore, it is verified that the pile anchor supporting coordinate interval can be used to evaluate the stability of the slope under dynamic load and provide a new method for the control of the dynamic load.

  4. 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.

  5. Numerical simulation of liquefaction susceptibility of soil interacting by single pile

    Directory of Open Access Journals (Sweden)

    Ahmad Asaadi

    2015-06-01

    Full Text Available Previous case histories have shown that soil liquefaction severely damaged many structures supported on pile foundations during earthquakes. As a result, evaluating the potential for instability is an important consideration for the safe and resistant design of deep foundation against earthquakes. In this study, the liquefaction susceptibility of saturated sand interacting by single concrete pile was simulated by means of finite difference method. A nonlinear effective stress analysis was used to evaluate soil liquefaction, and the soil-pile interaction was considered using interface elements. The parameter Ru was defined as the pore water pressure ratio to investigate liquefaction in the soil mass during time. A set of numerical models were carried out by three types of soil mass with various condensation (loose, semi-dense and dense under three ground motion with different predominant frequencies and peak accelerations. The effect of these parameters was studied using excess pore pressure, lateral movement and settlement time histories. It was found that the pile can affect the liquefaction susceptibility of soil by comparing the near pile and free field responses. However, for various soil and earthquake characteristics, it was found that the depth of soil liquefaction and triggering, varies.

  6. Design and Preparation of Carbon Based Composite Phase Change Material for Energy Piles

    Directory of Open Access Journals (Sweden)

    Haibin Yang

    2017-04-01

    Full Text Available Energy piles—A fairly new renewable energy concept—Use a ground heat exchanger (GHE in the foundation piles to supply heating and cooling loads to the supported building. Applying phase change materials (PCMs to piles can help in maintaining a stable temperature within the piles and can then influence the axial load acting on the piles. In this study, two kinds of carbon-based composite PCMs (expanded graphite-based PCM and graphite nanoplatelet-based PCM were prepared by vacuum impregnation for potential application in energy piles. Thereafter, a systematic study was performed and different characterization tests were carried out on two composite PCMs. The composite PCMs retained up to 93.1% of paraffin and were chemically compatible, thermally stable and reliable. The latent heat of the composite PCM was up to 152.8 J/g while the compressive strength of cement paste containing 10 wt % GNP-PCM was found to be 37 MPa. Hence, the developed composite PCM has potential for thermal energy storage applications.

  7. Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

    International Nuclear Information System (INIS)

    Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

    1995-01-01

    A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

  8. Kinematic Interaction and Rocking Effects on the Seismic Response of Viaducts on Pile Foundations

    International Nuclear Information System (INIS)

    Dezi, F.; Carbonari, S.; Leoni, G.

    2008-01-01

    This paper is aimed at providing a contribution for a more accurate and effective design of bridges founded on piles. A numerical model is employed herein to determine the stresses and displacements in the piles taking into account soil-foundation-structure interaction. A 3D finite element approach is developed for piles and superstructure whereas the soil is assumed to be a Winkler-type medium. The method is applied to single piers representative for a class of bridges. Varying the soil layers characteristics and the pile spacing (from 3 to 5 diameters), bending and axial stresses along piles as well as the pier base shear are computed. A comparison with respect to a fixed-base model is provided. Special issues such as the contribution of the soil profile, of the local amplification and of the rocking at the foundation level are discussed. Soil-structure interaction is found to be essential for effective design of bridges especially for squat piers and soft soil

  9. Mechanical analysis about the influence of tunnel excavation on vertical effect of adjacent bridge pile

    Science.gov (United States)

    Tian, Xiaoyan

    2017-08-01

    Tunnel excavation will bring additional deformation and internal force of adjacent bridge piles, if the deformation is large, it will threat the upper structure safety of the bridge. According to the complexity of the existing three - dimensional numerical simulation modeling and the time - consuming calculation, a two - stage analysis method of tunnel excavation based on Winkler foundation model was proposed. Firstly, Loganathan and Polous solutions were used to obtain the vertical displacement of the soil free field at the pile position when tunnel excavated, and the corresponding polynomial fitting displacement curve was taken. Secondly, the differential equation was established by means of the equilibrium condition of micro - element physical force and considering the pile group effect. Then, through the logical derivation, the calculation expressions of the tunnel excavation on the effect of the adjacent bridge pile (settlement, axial force and friction resistance) were obtained. Finally, based on the background of the tunnel project of Yanxing Door Station ˜ Xianning Road Station in Xi’an Metro Line 3, the feasibility and applicability of the proposed method were proved by comparing the calculated values with the numerical simulation values. It provides theoretical guidance for the effective analysis about the influence of tunnel excavation on the adjacent pile foundation effect.

  10. Design and Preparation of Carbon Based Composite Phase Change Material for Energy Piles

    Science.gov (United States)

    Yang, Haibin; Memon, Shazim Ali; Bao, Xiaohua; Cui, Hongzhi; Li, Dongxu

    2017-01-01

    Energy piles—A fairly new renewable energy concept—Use a ground heat exchanger (GHE) in the foundation piles to supply heating and cooling loads to the supported building. Applying phase change materials (PCMs) to piles can help in maintaining a stable temperature within the piles and can then influence the axial load acting on the piles. In this study, two kinds of carbon-based composite PCMs (expanded graphite-based PCM and graphite nanoplatelet-based PCM) were prepared by vacuum impregnation for potential application in energy piles. Thereafter, a systematic study was performed and different characterization tests were carried out on two composite PCMs. The composite PCMs retained up to 93.1% of paraffin and were chemically compatible, thermally stable and reliable. The latent heat of the composite PCM was up to 152.8 J/g while the compressive strength of cement paste containing 10 wt % GNP-PCM was found to be 37 MPa. Hence, the developed composite PCM has potential for thermal energy storage applications. PMID:28772752

  11. Autosizing Control Panel for Needle Bearing

    OpenAIRE

    Prof.A.R.Wadhekar,; Ms Jyoti R. Rajput

    2016-01-01

    A needle roller bearing is a bearing which uses small cylindrical rollers. Bearings are used to reduce friction of any rotating surface. Needle bearings have a large surface in contact with the bearing outer surfaces as compared to ball bearings. There is less added clearance(Diameter of the shaft and the diameter of the bearing are different) so they are much compact. The structure consists of a needle cage which contains the needle rollersthemselves and an outer race (The housin...

  12. Effect of heterogeneity and anisotropy related to the construction method on transfer processes in waste rock piles.

    Science.gov (United States)

    Lahmira, Belkacem; Lefebvre, René; Aubertin, Michel; Bussière, Bruno

    2016-01-01

    Waste rock piles producing acid mine drainage (AMD) are partially saturated systems involving multiphase (gas and liquid) flow and coupled transfer processes. Their internal structure and heterogeneous properties are inherited from their wide-ranging material grain sizes, their modes of deposition, and the underlying topography. This paper aims at assessing the effect of physical heterogeneity and anisotropy of waste rock piles on the physical processes involved in the generation of AMD. Generic waste rock pile conditions were represented with the numerical simulator TOUGH AMD based on those found at the Doyon mine waste rock pile (Canada). Models included four randomly distributed material types (coarse, intermediate, fine and very fine-grained). The term "randomly" as used in this study means that the vertical profile and spatial distribution of materials in waste rock piles (internal structure) defy stratigraphy principles applicable to natural sediments (superposition and continuity). The materials have different permeability and capillary properties, covering the typical range of materials found in waste rock piles. Anisotropy with a larger horizontal than vertical permeability was used to represent the effect of pile construction by benches, while the construction by end-dumping was presumed to induce a higher vertical than horizontal permeability. Results show that infiltrated precipitation preferentially flows in fine-grained materials, which remain almost saturated, whereas gas flows preferentially through the most permeable coarse materials, which have higher volumetric gas saturation. Anisotropy, which depends on pile construction methods, often controls global gas flow paths. Construction by benches favours lateral air entry close to the pile slope, whereas end-dumping leads to air entry from the surface to the interior of the pile by secondary gas convection cells. These results can be useful to construct and rehabilitate waste rock piles to minimize

  13. Permanent-Magnet Meissner Bearing

    Science.gov (United States)

    Robertson, Glen A.

    1994-01-01

    Permanent-magnet meissner bearing features inherently stable, self-centering conical configuration. Bearing made stiffer or less stiff by selection of magnets, springs, and spring adjustments. Cylindrical permanent magnets with axial magnetization stacked coaxially on rotor with alternating polarity. Typically, rare-earth magnets used. Magnets machined and fitted together to form conical outer surface.

  14. Superconducting bearings for flywheel applications

    DEFF Research Database (Denmark)

    Abrahamsen, A.B.

    2001-01-01

    A literature study on the application of superconducting bearings in energy storage flywheel systems. The physics of magnetic levitation and superconductors are presented in the first part of the report, followed by a discussion of the literature found onthe applications of superconducting bearings...

  15. What about the Javan Bear?

    NARCIS (Netherlands)

    Jentink, F.A.

    1898-01-01

    The other day I read in a dutch popular periodical a paper dealing with the different species of Bears and their geographical distribution. To my great surprise the Malayan Bear was mentioned from Java: the locality Java being quite new to me I wrote to the author of that paper and asked him some

  16. In-pile experiments on fuel rod behaviour during a LOCA

    International Nuclear Information System (INIS)

    Sepold, E.H.; Karb, E.H.; Pruessmann, M.

    1981-07-01

    This report describes the results of the Test Series G2/3 within the in-pile experimental program for the investigation of LWR fuel rod behavior. The results were obtained with single rods of a PWR design in the DK loop of the FR2 reactor at the Kernforschungszentrum Karlsruhe (KfK). The in-pile tests with the objective of investigating the influence of a nuclear environment on the mechanisms of fuel rod failure were being performed with irradiated and unirradiated rods. The main parameter of the test program ist the burnup, ranging from 2500 to 35000 MWd/t. The results of test series G2/3 (35000 MWd/t) with respect to the burst data, i.e. burst temperature, burst pressure, and burst strain, do not indicate major differences from the in-pile tests with unirradiated test specimens. (orig.) [de

  17. EQUATIONS OF NONLINEAR SOIL DAMAGE BASED ON RESULTS OF TESTING OF LATERALLY LOADED PILE MODELS

    Directory of Open Access Journals (Sweden)

    Buslov Anatoliy Semenovich

    2012-12-01

    Full Text Available Results of testing of laterally loaded pile models demonstrate that the "load -to-displacement" dependency has a nonlinear character. This dependency may be regarded as linear within the interval of (0.2…0.3 Pul only. Tests were performed in a box with displacement indicators and power equipment. The pile model length was 200 mm, and its diameter was 40 mm. A hollow steel tube was used as the material for tested piles. Based on the analysis of testing results, a pattern of the non-linear damage of the base was formulated. According to the pattern, the increase of the load intensity (damage factor m=Ph/Pul involves an increase in the damage of the continuity, or the rebuff ability of the soil foundation.

  18. The dispersal and impact of salt from surface storage piles the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Reith, C.C.; Louderbough, E.T.

    1986-01-01

    A comprehensive program of ecological studies occurs at the Waste Isolation Pilot Plant (WIPP) in an effort to detect and quantify impacts of excavated salt which is stored on the surface in two piles: one having originated in 1980, the other in 1984. Both piles are surrounded by berms which channel runoff to holding ponds, so nearly all dispersal is due to the resuspension, transport, and deposition of salt particles by wind. Ecological parameters which have been monitored since 1984 include: visual evidence (via photography), soil properties, microbial activity, leaf-litter decomposition, seedling emergence, plant foliar cover, and plant species diversity. These are periodically assessed at experimental plots near the salt piles, and at control plots several kilometers away

  19. 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...... ground heat extraction/injection activity , this paper provides a performance study of the energy pile-based ground source heat pump installation utilising operational data. The study demonstrates that the measured seasonal performance factors so far are lower than expected: 2.7 in heating mode and 4.......2 in cooling mode. Nevertheless, there is room for improvement if novel energy management strategies are applied. This highlights the relevance of considering the daily heating/cooling requirements of the building during the design phase of the heating and cooling system. Moreover, this study demonstrates...

  20. Comparison of Numerical Analyses with a Static Load Test of a Continuous Flight Auger Pile

    Directory of Open Access Journals (Sweden)

    Hoľko Michal

    2014-12-01

    Full Text Available The article deals with numerical analyses of a Continuous Flight Auger (CFA pile. The analyses include a comparison of calculated and measured load-settlement curves as well as a comparison of the load distribution over a pile's length. The numerical analyses were executed using two types of software, i.e., Ansys and Plaxis, which are based on FEM calculations. Both types of software are different from each other in the way they create numerical models, model the interface between the pile and soil, and use constitutive material models. The analyses have been prepared in the form of a parametric study, where the method of modelling the interface and the material models of the soil are compared and analysed.

  1. Boundary Value Problem for Analysis of Portal Double-Row Stabilizing Piles

    Directory of Open Access Journals (Sweden)

    Cheng Huang

    2013-01-01

    Full Text Available This paper presents a new numerical approach for computing the internal force and displacement of portal double-row piles used to stabilize potential landslide. First, the new differential equations governing the mechanical behaviour of the stabilizing pile are formulated and the boundary conditions are mathematically specified. Then, the problem is numerically solved by the high-accuracy Runge-Kutta finite difference method. A program package has been developed in MATLAB depending on the proposed algorithm. Illustrative examples are presented to demonstrate the validity of the developed program. In short, the proposed approach is a practical new idea for analyzing the portal double-row stabilizing pile as a useful supplement to traditional methods such as FEM.

  2. Acoustic Emission Signal Processing Technique to Characterize Reactor In-Pile Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Vivek Agarwal; Magdy Samy Tawfik; James A Smith

    2014-07-01

    Existing and developing advanced sensor technologies and instrumentation will allow non-intrusive in-pile measurement of temperature, extension, and fission gases when coupled with advanced signal processing algorithms. The transmitted measured sensor signals from inside to the outside of containment structure are corrupted by noise and are attenuated, thereby reducing the signal strength and signal-to-noise ratio. Identification and extraction of actual signal (representative of an in-pile phenomenon) is a challenging and complicated process. In this paper, empirical mode decomposition technique is proposed to reconstruct actual sensor signal by partially combining intrinsic mode functions. Reconstructed signal corresponds to phenomena and/or failure modes occurring inside the reactor. In addition, it allows accurate non-intrusive monitoring and trending of in-pile phenomena.

  3. An FPGA-Based Pulse Pile-up Rejection Technique for Photon Counting Imaging Detectors

    International Nuclear Information System (INIS)

    Hu Kun; Li Feng; Chen Lian; Jin Ge; Liang Fu-Tian

    2015-01-01

    A novel FPGA-based pulse pile-up rejection method for single photon imaging detectors is reported. The method is easy to implement in FPGAs for real-time data processing. The rejection principle and entire design are introduced in detail. The photon counting imaging detector comprises a micro-channel plate (MCP) stack, and a wedge and strip anode (WSA). The resolution mask pattern in front of the MCP can be reconstructed after data processing in the FPGA. For high count rates, the rejection design can effectively reduce the impact of the pulse pile-up on the image. The resolution can reach up to 140 μm. The pulse pile-up rejection design can also be applied to high-energy physics and particle detection. (paper)

  4. Fiber optic sensing system for temperature and gas monitoring in coal waste pile combustion environments

    Science.gov (United States)

    Viveiros, D.; Ribeiro, J.; Ferreira, J.; Lopez-Albada, A.; Pinto, A. M. R.; Perez-Herrera, R. A.; Diaz, S.; Lopez-Gil, A.; Dominguez-Lopez, A.; Esteban, O.; Martin-Lopez, S.; Auguste, J.-L.; Jamier, R.; Rougier, S.; Silva, S. O.; Frazão, O.; Santos, J. L.; Flores, D.; Roy, P.; Gonzalez-Herraez, M.; Lopez-Amo, M.; Baptista, J. M.

    2015-09-01

    It is presented an optical fiber sensing system projected to operate in the demanding conditions associated with coal waste piles in combustion. Distributed temperature measurement and spot gas sensing are requirements for such a system. A field prototype has been installed and is continuously gathering data, which will input a geological model of the coal waste piles in combustion aiming to understand their dynamics and evolution. Results are presented on distributed temperature and ammonia measurement, being noticed any significant methane emission in the short time period considered. Carbon dioxide is also a targeted gas for measurement, with validated results available soon. The assessment of this technology as an effective and reliable tool to address the problem of monitoring coal waste piles in combustion opens the possibility of its widespread application in view of the worldwide presence of coal related fires.

  5. Nonlinear control of magnetic bearings

    Science.gov (United States)

    Pradeep, A. K.; Gurumoorthy, R.

    1994-01-01

    In this paper we present a variety of nonlinear controllers for the magnetic bearing that ensure both stability and robustness. We utilize techniques of discontinuous control to design novel control laws for the magnetic bearing. We present in particular sliding mode controllers, time optimal controllers, winding algorithm based controllers, nested switching controllers, fractional controllers, and synchronous switching controllers for the magnetic bearing. We show existence of solutions to systems governed by discontinuous control laws, and prove stability and robustness of the chosen control laws in a rigorous setting. We design sliding mode observers for the magnetic bearing and prove the convergence of the state estimates to their true values. We present simulation results of the performance of the magnetic bearing subject to the aforementioned control laws, and conclude with comments on design.

  6. Flywheel Challenge: HTS Magnetic Bearing

    International Nuclear Information System (INIS)

    Werfel, F N; Floegel-Delor, U; Riedel, T; Rothfeld, R; Wippich, D; Goebel, B

    2006-01-01

    A 200 mm cylindrical engineering prototype high temperature superconducting (HTS) was designed and fabricated. Measurements show that the 17 kg PM rotor can suspend safely 1000 kg in axial direction and 470 kg radially. The rationale for the bearing performance is to stabilize a 400 kg rotor of a new compact 5 kWh/280 kW flywheel energy storage system (COM - FESS). Measurements of the magnetic bearing force, stiffness and drag-torque are presented indicated the successful targeting a milestone in the HTS bearing technology. The influence of the PM configuration and the YBCO temperature on the bearing performance was experimentally studied, providing high-force or high-stiffness behaviour. The axial stiffness 5 kN/mm at 0.5 mm displacement is the highest value of a HTS bearing we know

  7. FEM for stability analysis against overturning of portal water injection sheet pile

    Science.gov (United States)

    Lingyun, Liu; Haiyan, Guo; Qi, Sun

    2006-07-01

    Portal water injection sheet pile (PWISP), as a retaining wall, appeared in seashore engineering in 2000. Although there have been many systematic methods addressing the issue, there are very few focusing on the new structure because of the difficulties in defining the earth pressure between the two piles. A new method is proposed in this paper to obtain the earth pressure between the PWISPs. Stability analysis against overturning follows as a consequence. Using Finite Element Analysis (FEA) software ANSYS, both the nonlinear characteristics of the soil and thos of the contact elements are taken into account to obtain the earth pressure distribution on the contact surface. Based on the results of the FEA, Rankin's theory and the slip plane theory, the formula of the earth pressure on the inner surfaces between the piles is given. Assuming the PWISP as the analysis object and the earth pressure as an outside force acting upon it, the equation of stability against overturning of the PWISP is presented. Finally, some parameters are discussed about the stability of the PWISP against overturning, such as the embedded depth of the front pile, the distance between the two rows of piles, the internal friction angle and the cohesion of the earth. The results show that the increase of the cohesion and the internal friction angle will decrease the distance and the embedded depth, and therefore enhance the stability against overturning. Specifically, when the distance is 1/3 2/3 of the maximal excavation depth, the two rows of piles give the best performance in stability.

  8. Progress In Developing An In-Pile Acoustically Telemetered Sensor Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James A.; Garrett, Steven L.; Heibel, Michael D.; Agarwal, Vivek; Heidrich, Brenden J.

    2016-09-01

    A salient grand challenge for a number of Department of Energy programs such as Fuels Cycle Research and Development ( includes Accident Tolerant Fuel research and the Transient Reactor Test Facility Restart experiments), Light Water Sustainability, and Advanced Reactor Technologies is to enhance our fundamental understanding of fuel and materials behavior under irradiation. Robust and accurate in-pile measurements will be instrumental to develop and validate a computationally predictive multi-scale understanding of nuclear fuel and materials. This sensing technology will enable the linking of fundamental micro-structural evolution mechanisms to the macroscopic degradation of fuels and materials. The in situ sensors and measurement systems will monitor local environmental parameters as well as characterize microstructure evolution during irradiation. One of the major road blocks in developing practical robust, and cost effective in-pile sensor systems, are instrument leads. If a wireless telemetry infrastructure can be developed for in-pile use, in-core measurements would become more attractive and effective. Thus to be successful in accomplishing effective in-pile sensing and microstructure characterization an interdisciplinary measurement infrastructure needs to be developed in parallel with key sensing technology. For the discussion in this research, infrastructure is defined as systems, technology, techniques, and algorithms that may be necessary in the delivery of beneficial and robust data from in-pile devices. The architecture of a system’s infrastructure determines how well it operates and how flexible it is to meet future requirements. The limiting path for the effective deployment of the salient sensing technology will not be the sensors themselves but the infrastructure that is necessary to communicate data from in-pile to the outside world in a non-intrusive and reliable manner. This article gives a high level overview of a promising telemetry

  9. A new method for recovery of cellulose from lignocellulosic bio-waste: Pile processing.

    Science.gov (United States)

    Tezcan, Erdem; Atıcı, Oya Galioğlu

    2017-12-01

    This paper presents a new delignification method (pile processing) for the recovery of cellulose from lignocellulosic bio-wastes, adapted from heap leaching technology in metallurgy. The method is based on the stacking of cellulosic materials in a pile, irrigation of the pile with aqueous reactive solution from the top, lignin and hemicellulose removal and enrichment of cellulose by the reactive solution while percolation occurs through the bottom of the pile, recirculating the reactive solution after adjusting several values such as chemical concentrations, and allow the system run until the desired time or cellulose purity. Laboratory scale systems were designed using fall leaves (FL) as lignocellulosic waste materials. The ideal condition for FL was noted as: 0.1g solid NaOH addition per gram of FL into the irrigating solution resulting in instant increase in pH to about 13.8, later allowing self-decrease in pH due to delignification over time down to 13.0, at which point another solid NaOH addition was performed. The new method achieved enrichment of cellulose from 30% to 81% and removal of 84% of the lignin that prevents industrial application of lignocellulosic bio-waste using total of 0.3g NaOH and 4ml of water per gram of FL at environmental temperature and pressure. While the stirring reactions used instead of pile processing required the same amount of NaOH, they needed at least 12ml of water and delignification was only 56.1%. Due to its high delignification performance using common and odorless chemicals and simple equipment in mild conditions, the pile processing method has great promise for the industrial evaluation of lignocellulosic bio-waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Piled Higher and Deeper: 'The PhD Comics' as a Co-Creative Consumption Experience

    OpenAIRE

    Wohlfeil, Markus; Solé, Mar

    2013-01-01

    Ever since Jorge Cham launched the “Piled Higher and Deeper – The Life (or the Lack Thereof) in Academia” in 1997, this newspaper- and web-based comic strip series has enjoyed a growing popularity among postgraduate research students and academic staff members all over the world, for whom the main protagonists provide a humorous mirror to their own daily experiences of life in academia. Thus, the Piled Higher and Deeper comic strips appeal to a very distinct brand community that is narrowly d...

  11. In pile measurement of creep rate of stainless steel cladding tubes for fast reactor pins

    International Nuclear Information System (INIS)

    Calza Bini, A.; Cosoli, G.; Filacchioni, G.; Lanchi, M.; Nobili, A.; Pesce, E.; Rocca, U.V.; Rotoloni, P.L.

    1975-01-01

    Results are reported of a direct in pile measurement of creep on a cladding sample of 10cm length, under tensile stress of 22.82kg/mm 2 at a temperature of 550 0 during about 500 hours, up to an integrated flux of 2.6.10 20 n/cm 2 . Two identical samples were irradiated in the same temperature and flux conditions to be submitted to out of pile creep measurements together with other unirradiated samples. The aim of this first experiment was mainly to set up the device and to evaluate the kind and the quality of the available data

  12. Noise dependence with pile-up in the ATLAS Tile calorimeter

    CERN Document Server

    Araque Espinosa, Juan Pedro; The ATLAS collaboration

    2015-01-01

    The Tile Calorimeter, TileCal, is the central hadronic calorimeter of the ATLAS experiment and comprises alternating layers of steel (as absorber material) and plastic (as active material), known as tiles. Between 2009 and 2012, the LHC has performed better than expected producing proton-proton collisions at a very high rate. Under these challenging conditions not only the energy from an interesting event will be measured but also a component coming from other collisions. This component is referred to as pile-up noise. Studies carried out to better understand how pile-up affects calorimeter noise under different circumstances are described.

  13. Three dimensional analysis on lateral flow of liquefied ground and its mitigation by sheet pile walls

    Science.gov (United States)

    Kobayashi, Y.; Towhata, I.

    2005-01-01

    Since the design policy of countermeasures to liquefaction is currently prevention of liquefaction, conventional liquefaction analysis aims to predict the possibility of liquefaction at a target site. However, quantitative prediction of ground flow by liquefaction has been studied for new design policy that allows the deformation of liquefied ground if it is not critical. This paper presents a method for prediction of the ground deformation related liquefaction by viscous fluid model. Furthermore, the mitigation effect of a sheet pile wall is assessed by modeling a sheet pile wall as an elastic beam.

  14. Protection measurements on the Ulysse pile during its start-up

    International Nuclear Information System (INIS)

    Tattegrain, A.; Satge, H.

    1963-01-01

    The authors report measurements which aimed at verifying protection calculations made for the Ulysse atomic pile. They measured thermal, epithermal flows and the fast flow (when high enough to be measured). They also measured the gamma flow in some parts of the reactor. The authors describe the protections present on the different faces of the pile. These are made of baryte concrete and borated concrete. They indicate the detectors used to measure the different flows, and discuss the results obtained in the different channels

  15. An adjustable in-pile fan collimator for focusing at a neutron diffractometer

    CERN Document Server

    Stüsser, N

    2002-01-01

    An adjustable in-pile fan collimator was built and tested in a neutron diffraction set-up with a large horizontally curved monochromator for focusing in real and reciprocal space. For small samples, enhancements of intensity up to a factor of five without losing 2 theta-resolution are possible in comparison to a conventional diffractometer equipped with Soller-type collimators. Our geometry will be discussed and compared to both the conventional diffractometer and a focusing arrangement using an in-pile diaphragm.

  16. Physical scale modeling of single free head piles under lateral loading in cohesive soils

    Directory of Open Access Journals (Sweden)

    Edgar Leonardo Salamanca-Medina

    2017-06-01

    Full Text Available This paper presents the results of the small scale modeling of free head wood piles under horizontal loading in cohesive soils, tested in order to compare the results with analytical models proposed by various authors. Characteristic Load (CLM and P-Y Curves methods were used for the prediction of lateral deflections at the head of the piles and the method proposed by Broms for estimating the ultimate lateral load. These predictions were compared with the results of the physical modeling, obtaining a good approximation between them.

  17. The use of irradiation zones in the fuel element lattice of research piles

    International Nuclear Information System (INIS)

    Delattre, P.; Genthon, J.P.

    1960-01-01

    The first part of this report examines the advantages and disadvantages of the various types of canal which may be found in the fuel element lattice of research piles. Some examples relative to the piles EL2 and EL3 are discussed in detail. From the conclusions drawn in the last part, several norms are extracted which make it possible to define the conditions the various canals must fulfil in order that they can be used to the best possible advantage for each type of irradiation. (author) [fr

  18. 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......-scale tests at 1-g the determination of the friction angle and the Young’s modulus of elasticity of the soil are difficult and further these soil parameters varies greatly with depth. These uncertainties were avoided by application of an overburden pressure....

  19. Results of oscillation experiments on the Cesar and Marius piles - Uranium-Plutonium fuels

    International Nuclear Information System (INIS)

    Laponche, Bernard; Brunet, Max; Menessier, Denise; Morier, Francis; Basiuk, Marie-Jose; Tonolli, Jacky; Vanuxeem, Jacqueline

    1969-05-01

    The authors present, comment and discuss results obtained during three measurement campaigns performed on the Cesar and Marius atomic piles between 1965 and 1967 for the determination of some physical quantities (like the Plutonium η or its cross sections) from measurements of two signals which characterize the pile response to a central disturbance caused by the fuel to be studied. They more particularly address mass-corrected signals, the Uranium-235 and Boron calibration of the reactor, the local signal of the equivalent sample to a measured UPu sample. They indicate the different steps of interpretation of these results, present and discuss the measured results

  20. The MIT in-pile loops for coolant chemistry and corrosion studies

    International Nuclear Information System (INIS)

    Driscoll, M.J.; Harling, O.K.; Kohse, G.E.; Ballinger, R.G.

    1988-01-01

    A set of modular subsystems and components have been developed which can be combined in several ways to create in-pile loop facilities for experimental investigation of the effect of LWR reactor coolant chemistry on corrosion, both local and global, and on radionuclide transport and deposition. Care has been taken to scale the systems to achieve close similitude for parameters currently thought to control the phenomena of interest. Initial in-pile runs of the first of these facilities, a PWR coolant chemsitry loop, will take place soon. (author)

  1. Pile/shaft designs using artificial neural networks (i.e., genetic programming) with spatial variability considerations.

    Science.gov (United States)

    2014-03-01

    The work focused on the improvement of FB-DEEPs prediction of skin and tip resistance of concrete : piles and drilled shafts in Florida. For the work, data from 19 concrete pile sites and 18 drilled shaft sites were : collected. This included 458 ...

  2. Piled Higher and Deeper: Insights into 'The PhD Comics' as a Co-Creative Consumption Experience

    OpenAIRE

    Wohlfeil, Markus; Solé, Mar

    2013-01-01

    The Piled Higher and Deeper comic strips appeal to a very distinct brand community that is narrowly defined by common shared experiences as postgraduate researchers. This netnographic study explores whether and to what extent members of Piled Higher and Deeper brand community are getting actively involved in co-creation activities.

  3. 77 FR 69797 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in Port Townsend...

    Science.gov (United States)

    2012-11-21

    ... transfer span, lift towers, tower foundations, and a portion of the bridge seat and replace them with a new... existing transfer span, lift towers, tower foundations, and a portion of the bridge seat. Once the old... to pile installation, a total of 56 piles will be removed using vibratory extraction or a crane...

  4. Protection for work in the pressure tank of the pile G2; Protection des travaux dans le caisson de la pile G2

    Energy Technology Data Exchange (ETDEWEB)

    Chassany, J.Ph.; Rodier, J. [Commissariat a l' Energie Atomique, Service de Protection contre les Radiations, Marcoule (France). Centre d' Etudes Nucleaires

    1961-07-01

    While the pile was shut down after a three-month run at full power, the secondary circuit was cleaned and some alterations were carried out. The pile contained 100 tons of uranium, half of which made up the periphery and was irradiated uranium. The possibility of carrying on work inside the pressure tank was not considered at the time of construction. Because of the heat and the irradiation it was only possible to remain in the pressure tank for a limited period of time, and several operators received doses of the order of 1.5 rem. Cotton clothing gave satisfactory protection against contamination and was more comfortable than the vinyl equipment. The work lasted for 17 days and involved 881 incursions into the pressure tank. (author) [French] Un nettoyage et des modifications ont ete realises dans le circuit secondaire pendant l'arret de la pile apres un fonctionnement de trois mois a pleine puissance. La pile contenait 100 tonnes d'uranium dont la moitie, composant la peripherie, etait de l'uranium irradie. La possibilite d'entreprendre un travail a l'interieur du caisson n'avait pas ete envisage lors de la construction. Le temps de sejour dans le caisson etait a la fois limite par l'irradiation et la chaleur, plusieurs operateurs, ont integre une dose de l'ordre de 1,5 rem. Les vetements de coton ont apporte une protection contre la contamination satisfaisante et un confort relatif par rapport aux equipements de vinyle. L'intervention a dure 17 jours, a comporte 881 entrees dans le caisson. (auteur)

  5. Experimental study of reinforced concrete pile caps with external, embedded and partially embedded socket with smooth interface

    Directory of Open Access Journals (Sweden)

    R. Barros

    Full Text Available On Precast concrete structures the column foundation connections can occur through the socket foundation, which can be embedded, partially embedded or external, with socket walls over the pile caps. This paper presents an experimental study about two pile caps reinforced concrete with external, partially embedded and embedded socket submitted to central load, using 1:2 scaled models. In the analyzed models, the smooth interface between the socket walls and column was considered. The results are compared to a reference model that presents monolithic connections between the column and pile cap. It is observed that the ultimate load of pile cap with external sockets has the same magnitude as the reference pile cap, but the ultimate load of models with partially embedded and embedded socket present less magnitude than the reference model.

  6. Dynamic response of a laterally loaded fixed-head pile group in a transversely isotropic multilayered half-space

    Science.gov (United States)

    Ai, Zhi Yong; Li, Zhi Xiong; Wang, Li Hua

    2016-12-01

    The time-harmonic response of a laterally loaded fixed-head pile group embedded in a transversely isotropic multilayered half-space is investigated using a finite element and indirect boundary element coupling method. The piles are solved by the finite element method (FEM), while the soil can be modeled by the indirect boundary element method (BEM) with the aid of the fundamental solution for a transversely isotropic multilayered half-space in a cylindrical coordinate system. The governing equation of the pile-soil-pile dynamic interaction is established by applying the FEM-BEM coupling method. Numerical examples are carried out to validate the presented theory and to investigate influences of the soil's anisotropy and layering on the dynamic response of pile groups.

  7. International dosimetry experiment on the zero power pile of the Boris Kidric Institute at Vinca (Yugoslavia) (1961)

    International Nuclear Information System (INIS)

    Weill, J.; Furet, J.; Baillet, J.; Donvez, G.; Duchene, J.; Gras, R.; Mercier, R.; Chenouard, J.; Lecomte, J.

    1961-01-01

    On the occasion of the international dosimetry experiment on the zero power pile of the Yugoslavian Atomic Energy Centre at Vinca, the Commissariat a l'energie Atomique had agreed to prepare the measurement and security equipment and see to the manipulation of the heavy water, and in addition was responsible for the operation and the starting up of the pile during the experiment. The measurement and security apparatus, developed at Saclay and installed on the pile for low and high pressure runs, is listed, together with the safety equipment added near the control room. The various operations and manipulations carried out on the pile are described: filling with heavy water, starting up, determination of the critical level, testing the efficiency of the rods, operating the pile during the experiments. By operating to a carefully planned schedule, the experiments were, finished before the date fixed by the International Atomic Agency. (authors) [fr

  8. DESIGN HANDBOOK ON GAS BEARINGS FOR GYROSCOPES.

    Science.gov (United States)

    consisting of a plain journal for supporting radial loads flanked by two spiral-grooved thrust bearings to support double-acting thrust loads; (3) the spiral-grooved journal bearing ; and (4) the spiral-grooved conical bearing.

  9. Hybrid Hydrostatic/Transient Roller Bearing Assembly

    Science.gov (United States)

    Justak, John F.

    1992-01-01

    Proposed bearing assembly for shaft of high-speed turbopump includes both hydrostatic and rolling-element bearings. Rolling-element bearing unloaded at high speed by centrifugal expansion of outer race and transient retainer.

  10. Two pad axially grooved hydrostatic bearing

    Science.gov (United States)

    San Andres, Luis A. (Inventor)

    1995-01-01

    A hydrostatic bearing having two axial grooves on opposite sides of the bearing for breaking the rotational symmetry in the dynamic force coefficients thus reducing the whirl frequency ratio and increasing the damping and stiffness of the hydrostatic bearing.

  11. Deformation Analysis of Fixed Bearing Inclined Plane Thrust Bearing

    Directory of Open Access Journals (Sweden)

    LI Yong--hai

    2017-02-01

    Full Text Available According to the theory of lubrication,Numerical simulation of the deformation of the thrust bearing of the fixed inclined plane was carried out,by finite element numerical analysis method and using the ANSYS software. The mathematical model of the oil film shape control equations about of the deformation and bearing is established. Analytical result showed that the force caused the tile surface generating concave deformation,and convex deformation increased with the height and the size of the load and bearing;Tile surface temperature generated convex deformation and increased with the height and the size of the temperature of bearing bush;The actual deformation of the tile surface is the superposition of the force and the thermal deformation. This conclusion can provide reference for the design and the application of thrust bearing,to reduce the tile surface,which is not conducive to the carrying capacity of the concave deformation.

  12. EFFECT OF BEARING MACROGEOMETRY ON BEARING PERFORMANCE IN ELASTOHYDRODYNAMIC LUBRICATION

    Directory of Open Access Journals (Sweden)

    Emin GÜLLÜ

    2000-01-01

    Full Text Available During manufacturing, ideal dimension and mutual positioning of machine elements proposed in project desing can be achieved only within certain range of tolerances. These tolerances, being classified in two groups, related to micro and macro geometry of machine elements, don't have to effect the functioning of these elements. So, as for all machine elements, investigation of the effects of macro and micro tolerances for journal bearings is important. In this study, we have investigated the effect of macro geometric irregularities of journal bearings on performance characteristics. In this regard, we have studied the change of bearing performance in respect to deviation from ideal circle for an elliptic shaft with small ovality rolling in circular journal bearing.

  13. Bears, Big and Little. Young Discovery Library Series.

    Science.gov (United States)

    Pfeffer, Pierre

    This book is written for children 5 through 10. Part of a series designed to develop their curiosity, fascinate them and educate them, this volume describes: (1) the eight species of bears, including black bear, brown bear, grizzly bear, spectacled bear, sun bear, sloth bear, polar bear, and giant panda; (2) geographical habitats of bears; (3)…

  14. Non-contacting "snubber bearing" for passive magnetic bearing systems

    Science.gov (United States)

    Post, Richard F

    2017-08-22

    A new non-contacting magnetic "snubber" bearing is provided for application to rotating systems such as vehicular electromechanical battery systems subject to frequent accelerations. The design is such that in the equilibrium position the drag force of the snubber is very small (milliwatts). However in a typical case, if the rotor is displaced by as little as 2 millimeters a large restoring force is generated without any physical contact between the stationary and rotating parts of the snubber bearing.

  15. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest). Pile Perch, Striped Seaperch, and Rubberlip Seaperch

    Science.gov (United States)

    1989-07-01

    pile perch Class .. ......... ... Osteichthyes (Figure 1) Order .. .......... .Perciformes Local common names . . pile surfperch, Family...Embiotocidae fork-tail perch, porgy Class .. ......... ... Osteichthyes Geographic range: Port Wrangell, Order .. .......... .Perciformes Alaska, to...SAN DIEGO Figure 2. California distribution of pile perch, striped seaperch, and rubberlip seaperch. 2 Class .... .......... Osteichthyes Ground

  16. Thin Dense Chrome Bearing Insertion Program

    National Research Council Canada - National Science Library

    Rhoads, Mark

    1997-01-01

    .... TDC coated bearings demonstrated improved corrosion and contamination resistance. TDC coated bearings also demonstrated acceptable performance during thermal cycle, oil-off, and induced defect conditions...

  17. Identification and rejection of pile-up jets at high pseudorapidity with the ATLAS detector

    Energy Technology Data Exchange (ETDEWEB)

    Aaboud, M. [Univ. Mohamed Premier et LPTPM, Oujda (Morocco). Faculte des Sciences; Aad, G. [CPPM, Aix-Marseille Univ. et CNRS/IN2P3, Marseille (France); Abbott, B. [Oklahoma Univ., Norman, OK (United States). Homer L. Dodge Dept. of Physics and Astronomy; Collaboration: ATLAS Collaboration; and others

    2017-09-15

    The rejection of forward jets originating from additional proton-proton interactions (pile-up) is crucial for a variety of physics analyses at the LHC, including Standard Model measurements and searches for physics beyond the Standard Model. The identification of such jets is challenging due to the lack of track and vertex information in the pseudorapidity range vertical stroke η vertical stroke > 2.5. This paper presents a novel strategy for forward pile-up jet tagging that exploits jet shapes and topological jet correlations in pile-up interactions. Measurements of the per-jet tagging efficiency are presented using a data set of 3.2 fb{sup -1} of proton-proton collisions at a centre-of-mass energy of 13 TeV collected with the ATLAS detector. The fraction of pile-up jets rejected in the range 2.5 < vertical stroke η vertical stroke < 4.5 is estimated in simulated events with an average of 22 interactions per bunch-crossing. It increases with jet transverse momentum and, for jets with transverse momentum between 20 and 50 GeV, it ranges between 49% and 67% with an efficiency of 85% for selecting hard-scatter jets. A case study is performed in Higgs boson production via the vector-boson fusion process, showing that these techniques mitigate the background growth due to additional proton-proton interactions, thus enhancing the reach for such signatures. (orig.)

  18. Geotechnical maps for recommendation on bored pile capacity in Nakhon Ratchasima municipality, Thailand

    Directory of Open Access Journals (Sweden)

    Suksun Horpibulsuk

    2013-08-01

    Full Text Available This paper presents the development of geotechnical maps in Nakhon Ratchasima municipality, Nakhon Ratchasima province, Thailand based on the boring logs and in situ test results collected from public and private sector sources. The standard penetration number, N was used to identify the soil type. The soil deposits in Nakhon Ratchasima municipality are divided into three layers: medium-to-stiff silty clay with N 50. The medium-to-stiff silty clay layer has a thickness varying from 1.8 to 7.5 metres and an average N value of 14 with a relatively low standard deviation of 1.08. The first hard silty clay layer has a thickness varying from 1.2 to 3.0 metres and an average N value of 42 with a standard deviation of 1.37. For a practical application in foundation engineering in which the pile tips of the bored piles are located in the second hard stratum with N > 50, eight pile tip zones with approximated load capacity are recommended for pile lengths of 3-10 metres.

  19. Allowable temperature rise in tubes of the piles: Precautions against boiling

    Energy Technology Data Exchange (ETDEWEB)

    Woods, W.K.

    1945-09-27

    In the design of the pile, it was considered advisable never to impose so great a heat load on any tube that the available header pressure would be insufficient to sweep the tube free of vapor if boiling should accidentally be initiated in the tube. Figures are given for the maximum temperature rises permissible, as function of header pressure and orifice diameter.

  20. FPGA-Based Pulse Pile-Up Correction With Energy and Timing Recovery.

    Science.gov (United States)

    Haselman, M D; Pasko, J; Hauck, S; Lewellen, T K; Miyaoka, R S

    2012-10-01

    Modern field programmable gate arrays (FPGAs) are capable of performing complex discrete signal processing algorithms with clock rates well above 100 MHz. This, combined with FPGA's low expense, ease of use, and selected dedicated hardware make them an ideal technology for a data acquisition system for a positron emission tomography (PET) scanner. The University of Washington is producing a high-resolution, small-animal PET scanner that utilizes FPGAs as the core of the front-end electronics. For this scanner, functions that are typically performed in dedicated circuits, or offline, are being migrated to the FPGA. This will not only simplify the electronics, but the features of modern FPGAs can be utilized to add significant signal processing power to produce higher quality images. In this paper we report on an all-digital pulse pile-up correction algorithm that has been developed for the FPGA. The pile-up mitigation algorithm will allow the scanner to run at higher count rates without incurring large data losses due to the overlapping of scintillation signals. This correction technique utilizes a reference pulse to extract timing and energy information for most pile-up events. Using pulses acquired from a Zecotech Photonics MAPD-N with an LFS-3 scintillator, we show that good timing and energy information can be achieved in the presence of pile-up utilizing a moderate amount of FPGA resources.

  1. Diverse archaeal community of a bat guano pile in Domica Cave (Slovak Karst, Slovakia)

    Czech Academy of Sciences Publication Activity Database

    Chroňáková, Alica; Horák, Aleš; Elhottová, Dana; Krištůfek, Václav

    2009-01-01

    Roč. 54, č. 5 (2009), s. 436-446 ISSN 0015-5632 R&D Projects: GA MŠk LC06066 Institutional research plan: CEZ:AV0Z60660521; CEZ:AV0Z60220518 Keywords : archaea l community * bat guano pile * Domica Cave Subject RIV: EH - Ecology, Behaviour Impact factor: 0.978, year: 2009

  2. Thermal integrity profiling for augered cast-in-place piles - implementation plan.

    Science.gov (United States)

    2017-08-01

    This study was the second in a two-part research program focused on assessing the feasibility of using thermal integrity profiling (TIP) as a quality assurance tool for Augered Cast-In-Place (ACIP) piles. This was made possible by coordinating with t...

  3. Reducing seismic risk to highway mobility : assessment and design of pile foundations affected by lateral loading.

    Science.gov (United States)

    2013-04-01

    Damage in pile supported structures due to liquefaction and liquefaction induced deformation were reported in past earthquakes around the world (eg, Ansal et al. 1999, Seed et al. 1990, EERI 2010, EERI 2011, GEER 2010a, GEER 2010b, GEER 2011). For ex...

  4. Assessment of Calculation Procedures for Piles in Clay Based on Static Loading Tests

    DEFF Research Database (Denmark)

    Augustesen, Anders; Andersen, Lars

    2008-01-01

    Numerous methods are available for the prediction of the axial capacity of piles in clay. In this paper, two well-known models are considered, namely the current API-RP2A (1987 to present) and the recently developed ICP method. The latter is developed by Jardine and his co-workers at Imperial Col...

  5. Pile sorting innovations: exploring gender norms, power and equity in sub-Saharan Africa.

    Science.gov (United States)

    Bourey, Christine; Stephenson, Rob; Bartel, Doris; Rubardt, Marcie

    2012-01-01

    Understanding gender norms, power and equity is important for developing successful sexual and reproductive health interventions. However, little attention has been given to how to capture the gender ideals and imbalances that inform these relationships in low resource settings. Pile sorting exercises were conducted in four gender-segregated focus groups in Ethiopia and Kenya. Each group received cards illustrated with a man, woman and man and woman together and cards labelled with duties and decisions. Participants discussed and decided together whether men, women or both performed each duty and decision and assigned the cards accordingly. Participants then reflected on and physically manipulated the piles to challenge gender norms, investigate role flexibility and identify agents of social change. Data collected included photographs of the pile sorts and recordings of the discussions. Conducting pile sorting within focus group discussions enabled comparative analyses of gender norms, while enriching data by focusing discussions and encouraging consensus building. Innovative applications facilitated participants' abilities to engage abstract concepts, reflecting on issues of gender norms, power and equity.

  6. Comparison of Numerical Analyses with a Static Load Test of a Continuous Flight Auger Pile

    Science.gov (United States)

    Hoľko, Michal; Stacho, Jakub

    2014-12-01

    The article deals with numerical analyses of a Continuous Flight Auger (CFA) pile. The analyses include a comparison of calculated and measured load-settlement curves as well as a comparison of the load distribution over a pile's length. The numerical analyses were executed using two types of software, i.e., Ansys and Plaxis, which are based on FEM calculations. Both types of software are different from each other in the way they create numerical models, model the interface between the pile and soil, and use constitutive material models. The analyses have been prepared in the form of a parametric study, where the method of modelling the interface and the material models of the soil are compared and analysed. Our analyses show that both types of software permit the modelling of pile foundations. The Plaxis software uses advanced material models as well as the modelling of the impact of groundwater or overconsolidation. The load-settlement curve calculated using Plaxis is equal to the results of a static load test with a more than 95 % degree of accuracy. In comparison, the load-settlement curve calculated using Ansys allows for the obtaining of only an approximate estimate, but the software allows for the common modelling of large structure systems together with a foundation system.

  7. 77 FR 43259 - Takes of Marine Mammals Incidental to Specified Activities; Pile Driving for Honolulu Seawater...

    Science.gov (United States)

    2012-07-24

    ... offshore pipe would pump cold, deep seawater to a pump station onshore. Pile driving operations would... cold, productive coastal waters. In the North Pacific, there are at least three separate humpback... sensitivity of the receptor (Richardson et al., 1995). Marine mammal reactions to sound may depend on sound...

  8. Asymptotic analysis of a pile-up of regular edge dislocation walls

    KAUST Repository

    Hall, Cameron L.

    2011-12-01

    The idealised problem of a pile-up of regular dislocation walls (that is, of planes each containing an infinite number of parallel, identical and equally spaced dislocations) was presented by Roy et al. [A. Roy, R.H.J. Peerlings, M.G.D. Geers, Y. Kasyanyuk, Materials Science and Engineering A 486 (2008) 653-661] as a prototype for understanding the importance of discrete dislocation interactions in dislocation-based plasticity models. They noted that analytic solutions for the dislocation wall density are available for a pile-up of regular screw dislocation walls, but that numerical methods seem to be necessary for investigating regular edge dislocation walls. In this paper, we use the techniques of discrete-to-continuum asymptotic analysis to obtain a detailed description of a pile-up of regular edge dislocation walls. To leading order, we find that the dislocation wall density is governed by a simple differential equation and that boundary layers are present at both ends of the pile-up. © 2011 Elsevier B.V.

  9. Investigation on the Effect of Drained Strength when Designing Sheet Pile Walls

    DEFF Research Database (Denmark)

    Iversen, Kirsten Malte; Nielsen, Benjaminn Nordahl; Augustesen, Anders Hust

    Long sheet pile walls are constructed in the cities as an integrated part of deep excavations for e.g. parking lots, pumping stations, reservoirs, and cut and cover tunnels. To minimise costs, the strength of the soil needs to be determined in the best possible way. The drained strength of clay...

  10. Contaminant transport, revegetation, and trace element studies at inactive uranium mill tailings piles

    International Nuclear Information System (INIS)

    Dreesen, D.R.; Marple, M.L.; Kelley, N.E.

    1978-01-01

    The stabilization of inactive uranium mill tailings piles is presently under study. These studies have included investigations of stabilizing tailings by attempting to establish native vegetation without applying irrigation. Examination of processes which transport tailings or associated contaminants into the environment has been undertaken to better understand the containment provided by various stabilization methods. The uptake of toxic trace elements and radionuclides by vegetation has been examined as a mechanism of contaminant transport. The source terms of 222 Rn from inactive piles have been determined as well as the attenuation of radon flux provided by shallow soil covers. The possibility of shallow ground water contamination around an inactive pile has been examined to determine the significance of ground water transport as a mode of contaminant migration. The rationale in support of trace element studies related to uranium milling activities is presented including the enrichment, migration, and toxicities of trace elements often associated with uranium deposits. Some concepts for the stabilization of inactive piles are presented to extrapolate from research findings to practical applications. 25 references, 8 tables

  11. Durability assessment of concrete sheet piling in the 'De Betuweroute' railway line

    NARCIS (Netherlands)

    Peelen, W.H.A.; Polder, R.B.

    2004-01-01

    Assessment of the durability of prestressed concrete sheet piles under the interference of CP gas pipeline system current, established that due to their low magnitude, these currents do not compromise the required 100-year service life of the structures. The sophisticated numerical modelling tools

  12. Towards a complete physically based forecast model for underwater noise related to impact pile driving.

    Science.gov (United States)

    Fricke, Moritz B; Rolfes, Raimund

    2015-03-01

    An approach for the prediction of underwater noise caused by impact pile driving is described and validated based on in situ measurements. The model is divided into three sub-models. The first sub-model, based on the finite element method, is used to describe the vibration of the pile and the resulting acoustic radiation into the surrounding water and soil column. The mechanical excitation of the pile by the piling hammer is estimated by the second sub-model using an analytical approach which takes the large vertical dimension of the ram into account. The third sub-model is based on the split-step Padé solution of the parabolic equation and targets the long-range propagation up to 20 km. In order to presume realistic environmental properties for the validation, a geoacoustic model is derived from spatially averaged geological information about the investigation area. Although it can be concluded from the validation that the model and the underlying assumptions are appropriate, there are some deviations between modeled and measured results. Possible explanations for the observed errors are discussed.

  13. In Vitro Evaluation and Mechanism Analysis of the Fiber Shedding Property of Textile Pile Debridement Materials

    Science.gov (United States)

    Fu, Yijun; Xie, Qixue; Lao, Jihong; Wang, Lu

    2016-01-01

    Fiber shedding is a critical problem in biomedical textile debridement materials, which leads to infection and impairs wound healing. In this work, single fiber pull-out test was proposed as an in vitro evaluation for the fiber shedding property of a textile pile debridement material. Samples with different structural design (pile densities, numbers of ground yarns and coating times) were prepared and estimated under this testing method. Results show that single fiber pull-out test offers an appropriate in vitro evaluation for the fiber shedding property of textile pile debridement materials. Pull-out force for samples without back-coating exhibited a slight escalating trend with the supplement in pile density and number of ground yarn plies, while back-coating process significantly raised the single fiber pull-out force. For fiber shedding mechanism analysis, typical pull-out behavior and failure modes of the single fiber pull-out test were analyzed in detail. Three failure modes were found in this study, i.e., fiber slippage, coating point rupture and fiber breakage. In summary, to obtain samples with desirable fiber shedding property, fabric structural design, preparation process and raw materials selection should be taken into full consideration. PMID:28773428

  14. Influences of plasticity on a sheet pile phased stochastic FE analysis

    NARCIS (Netherlands)

    Boer, A. de; Waarts, P.H.

    2000-01-01

    The paper deals with the stochastic analysis of the stability of a sheet pile soil structure. Most areas in the Netherlands have layered soil conditions. The decisive parameter in the nonlinear FE analysis is the behaviour of the soil. For layered soil conditions, the correct modelling of the

  15. Analysis of Dynamic Coupling Characteristics of the Slope Reinforced by Sheet Pile Wall

    Directory of Open Access Journals (Sweden)

    H. L. Qu

    2017-01-01

    Full Text Available Large deformation of slope caused by earthquake can lead to the loss of stability of slope and its retaining structures. At present, there have been some research achievements about the slope reinforcement of stabilizing piles. However, due to the complexity of the structural system, the coupling relationship between soil and pile is still not well understood. Hence it is of great necessity to study its dynamic characteristics further. In view of this, a numerical model was established by FLAC3D in this paper, and the deformation and stress nephogram of sheet pile wall in peak ground motion acceleration (PGA at 0.1 g, 0.2 g, and 0.4 g were obtained. Through the analysis, some conclusions were obtained. Firstly, based on the nephogram of motion characteristics and the positions of the slip surface and the retaining wall, the reinforced slope can be divided into 6 sections approximatively, namely, the sliding body parts of A, B, C, D, and E and the bedrock part F. Secondly, the deformation and stress distributions of slope reinforced by sheet pile wall were carefully studied. Based on the results of deformation calculation from time history analysis, the interaction force between structure and soil can be estimated by the difference of peak horizontal displacements, and the structure-soil coupling law under earthquake can be studied by this approach.

  16. Remote-welding technique for assembling in-pile IASCC capsule in hot cell

    International Nuclear Information System (INIS)

    Kawamata, Kazuo; Ishii, Toshimitsu; Kanazawa, Yoshiharu; Iwamatsu, Shigemi; Ohmi, Masao; Shimizu, Michio; Matsui, Yoshinori; Saito, Jun-ichi; Ugachi, Hirokazu; Kaji, Yoshiyuki; Tsukada, Takashi

    2006-01-01

    In order to investigate behavior of the irradiation assisted stress corrosion cracking (IASCC) caused by the simultaneous effects of neutron irradiation and high temperature water environment in such a light water reactor (LWR), it is necessary to perform crack growth tests in an in-pile IASCC capsule irradiated in the Japan Materials Testing Reactor (JMTR). The development of the remote-welding technique is essential for remotely assembling the in-pile IASCC capsule installing the pre-irradiated CT specimens. This report describes a new remote-welding machine developed for assembling the in-pile IASCC capsule. The remote-welding technique that the capsule tube is rotated light under the fixed torch was applied to the machine for the welding of thick and large-diameter tubes. The assembly work of four in-pile IASCC capsules having pre-irradiated CT specimens in the hot cell was succeeded for performing the crack growth test under the neutron irradiation in JMTR. The irradiation test of two capsules has been already finished in JMTR without problems. (author)

  17. 77 FR 2701 - Takes of Marine Mammals Incidental to Specified Activities; Pile Placement for ORPC Maine's...

    Science.gov (United States)

    2012-01-19

    ... animals may have been more tolerant of exposures because of motivation to return to a safe location or... project lead (or other authorized individual) who would then be required to delay pile driving until the... marine mammal, and the lead PSO determines that the cause of the injury or death is unknown and the death...

  18. 77 FR 59904 - Takes of Marine Mammals Incidental to Specified Activities; Pile Driving for Honolulu Seawater...

    Science.gov (United States)

    2012-10-01

    ..., whereas free-ranging animals may have been more tolerant of exposures because of motivation to return to a... pile driving, the observer will notify the on- site project lead (or other authorized individual) who... operations; and (2) notify the onsite project lead (or other authorized individual) if a large whale is seen...

  19. NEET In-Pile Ultrasonic Sensor Enablement-FY 2012 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    JE Daw; JL Rempe; BR Tittmann; B Reinhardt; P Ramuhalli; R Montgomery; HT Chien

    2012-09-01

    Several Department Of Energy-Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development, Advanced Reactor Concepts, Light Water Reactor Sustainability, and Next Generation Nuclear Plant programs, are investigating new fuels and materials for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials when irradiated. The Nuclear Energy Enabling Technology (NEET) Advanced Sensors and Instrumentation (ASI) in-pile instrumentation development activities are focused upon addressing cross-cutting needs for DOE-NE irradiation testing by providing higher fidelity, real-time data, with increased accuracy and resolution from smaller, compact sensors that are less intrusive. Ultrasonic technologies offer the potential to measure a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes, under harsh irradiation test conditions. There are two primary issues associated with in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. Due to the harsh nature of in-pile testing, and the range of measurements that are desired, an enhanced signal processing capability is needed to make in-pile ultrasonic sensors viable. This project addresses these technology deployment issues.

  20. Comparison of Design Methods for Axially Loaded Driven Piles in Cohesionless Soil

    DEFF Research Database (Denmark)

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

    2012-01-01

    For offshore wind turbines on deeper waters, a jacket sub-structure supported by axially loaded piles is thought to be the most suitable solution. The design method recommended by API and two CPT-based design methods are compared for two uniform sand profiles. The analysis show great difference...