WorldWideScience

Sample records for bridge design

  1. General framework for bridge life cycle design

    Institute of Scientific and Technical Information of China (English)

    Junhai MA; Airong CHEN; Jun HE

    2009-01-01

    Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environ-mental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes.

  2. General design of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Xigang; Yuan Hong; Pei Minshan; Dai Jie; Xu Lin

    2009-01-01

    The main span of Sutong Bridge is a double-pylon, double-plane cable-stayed bridge with steel box girder, which has the world's longest central span of 1 088 m within cable-stayed bridges. To overcome problems caused by severe meteorological conditions, perplexing hydrological conditions, deep buried bedrock and higher navigation level, many new technics and methods were created. Keys including structural system, steel box girder, stayed cable, tower, pier, tower foundation, collision avoidance system, wind-resistance, seismic-resistance, structural nonlinear response and structural static stability were presented individually in this paper.

  3. Design of bridges against large tectonic deformation

    Institute of Scientific and Technical Information of China (English)

    I.Anastasopoulost; G.Gazetas; V.Drosos; T.Georgarakos; R.Kourkoulis

    2008-01-01

    The engineering community has devoted much effort to understanding the response of soil-structure systems to seismic ground motions,but little attention to the effects of an outcropping fault offset.The 1999 earthquakes of Turkey and Taiwan,offering a variety of case histories of structural damage due to faulting,have (re)fueled the interest on the subject.This paper presents a methodology for design of bridges against tectonic deformation.The problem is decoupled in two analysis steps:the first (at the local level) deals with the response of a single pier and its foundation to fault rupture propagating through the soil,and the superstructure is modeled in a simplified manner;and the second (at the global level)investigates detailed models of the superstructure subjected to the support (differential) displacements of Step 1.A parametric study investigates typical models of viaduct and overpass bridges,founded on piles or caissons.Fixed-head piled foundations are shown to be rather vulnerable to faulting-induced deformation.End-bearing piles in particular are unable to survive bedrock offsets exceeding 10 cm.Floating piles perform better,and if combined with hinged pile-to-cap connections,they could survive much larger offsets.Soil resilience is beneficial in reducing pile distress.Caisson foundations are almost invariably successful.Statically-indeterminate superstructures are quite vulnerable,while statically-determinate are insensitive (allowing differential displacements and rotations without suffering any distress).For large-span cantilever construction bridges,where a statically determinate system is hardly an option,inserting resilient seismic isolation bearings is advantageous as long as ample seating can prevent the deck from falling off the supports.An actual application of the developed method is presented for a major bridge,demonstrating the feasibility of design against tectonic deformation.

  4. Jointless and Smoother Bridges: Behavior and Design of Piles

    OpenAIRE

    Frosch, Robert J; Chovichien, Voraniti; Durbin, Katrinna; Fedroff, David

    2006-01-01

    Integral abutment bridges have been used in the United States for decades. By eliminating expensive expansion joints, the piles supporting the end bent accommodate the total thermal movement of the bridge. Currently, integral bridges are designed based upon experience, and a rational design specification has not been developed. Furthermore, the interaction of the abutment, pile, and soil remains uncertain. A better understanding regarding the behavior of this system is needed. The objective o...

  5. Bridges analysis, design, structural health monitoring, and rehabilitation

    CERN Document Server

    Bakht, Baidar

    2015-01-01

    This book offers a valuable guide for practicing bridge engineers and graduate students in structural engineering; its main purpose is to present the latest concepts in bridge engineering in fairly easy-to-follow terms. The book provides details of easy-to-use computer programs for: ·      Analysing slab-on-girder bridges for live load distribution. ·      Analysing slab and other solid bridge components for live load distribution. ·      Analysing and designing concrete deck slab overhangs of girder bridges under vehicular loads. ·      Determining the failure loads of concrete deck slabs of girder bridges under concentrated wheel loads. In addition, the book includes extensive chapters dealing with the design of wood bridges and soil-steel bridges. Further, a unique chapter on structural health monitoring (SHM) will help bridge engineers determine the actual load carrying capacities of bridges, as opposed to their perceived analytical capacities. The chapter addressing structures...

  6. Use of UHPC in Bridge Structures: Material Modeling and Design

    Directory of Open Access Journals (Sweden)

    Oguz Gunes

    2012-01-01

    Full Text Available Ultra-high-performance concrete (UHPC is a promising new class of concrete material that is likely to make a significant contribution to addressing the challenges associated with the load capacity, durability, sustainability, economy, and environmental impact of concrete bridge infrastructures. This paper focuses on the material modeling of UHPC and design of bridge girders made of UHPC. A two-phase model used for modeling the behavior of UHPC was briefly discussed, and the model was implemented in a preliminary design case study. Based on the implemented design and the reported use of UHPC in bridge applications, the advantages, limitations, and future prospects of UHPC bridges were discussed, highlighting the need for innovative research and design to make optimum use of the favorable properties of the material in bridge structures.

  7. Critical traffic loading for the design of prestressed concrete bridge

    International Nuclear Information System (INIS)

    A study has been carried out to determine critical traffic loadings for the design of bridge superstructures. The prestressed concrete girder bridge already constructed in Lahore is selected for the analysis as an example. Standard traffic loadings according to AASHTO (American Association of State Highway and Transportation Officials) and Pakistan Highway Standards are used for this purpose. These include (1) HL-93 Truck, (2) Lane and (3) Tandem Loadings in addition to (4) Military tank loading, (5) Class-A, (6) Class-B and (7) Class-AA loading, (8) NLC (National Logistic Cell) and (9) Volvo truck loadings. Bridge superstructure including transom beam is analyzed Using ASD and LRFD (Load and Resistance Factor Design) provisions of AASHTO specifications. For the analysis, two longer and shorter spans are selected. This includes the analysis of bridge deck; interior and exterior girder; a typical transom beam and a pier. Dead and live loading determination is carried out using both computer aided and manual calculations. Evaluation of traffic loadings is done for all the bridge components to find out the critical loading. HL-93 loading comes out to be the most critical loading and where this loading is not critical in case of bridge decks; a factor of 1.15 is introduced to make it equivalent with HL-93 -Ioading. SAP-2000 (Structural Engineering Services of Pakistan) and MS-Excel is employed for analysis of bridge superstructure subjected to this loading. Internal forces are obtained for the structural elements of the bridge for all traffic loadings mentioned. It is concluded that HL-93 loading can be used for the design of prestressed concrete girder bridge. Bridge design authorities like NHA (National Highway Authority) and different cities development authorities are using different standard traffic loadings. A number of suggestions are made from the results of the research work related to traffic loadings and method of design. These recommendations may be

  8. Bridging the Gap between Instructional Design and Double Loop Learning

    NARCIS (Netherlands)

    Spoelstra, Howard; Rusman, Ellen; Van Bruggen, Jan; Koper, Rob; Matera, Maristella

    2008-01-01

    Spoelstra, H., Rusman, E., Van Bruggen, J., Koper, R., & Matera, M. (2008). Bridging the Gap Between Instructional Design and Double-Loop Learning. International Journal of Web-Based Learning and Teaching Technologies, 3(1), 79-89.

  9. Bridging the Gap between Design and Engineering in Packaging Development

    OpenAIRE

    Ten Klooster, R.; Lutters, D.

    2009-01-01

    Packaging designers often come up with splendid design proposals, without being aware of technical, marketing or economical restrictions. This leads to infeasible proposals, so many packaging design projects fail. To bridge the gap between design and marketing, a tool has been developed that shows several designs to an extensive community. Designers now have the possibility to get feedback of the target market on the design proposals. In a case study (redesigning a packaging), the...

  10. Optimum design of concrete cable-stayed bridges

    Science.gov (United States)

    Martins, Alberto M. B.; Simões, Luís M. C.; Negrão, João H. J. O.

    2016-05-01

    The design of cable-stayed bridges involves a significant number of design variables and design objectives. The concrete cable-stayed bridge optimization is formulated here as a multi-objective optimization problem with objectives of minimum cost, minimum deflections and minimum stresses. A numerical method is developed to obtain the optimum design of such structures. This numerical method includes: structural analysis, sensitivity analysis and optimization. The structural analysis accounts for all the relevant effects (concrete time-dependent effects, construction stages and geometrical nonlinear effects). The structural response to changes in the design variables is achieved by a discrete direct sensitivity analysis procedure, and an entropy-based approach was used for structural optimization. The features and applicability of the proposed method are demonstrated by numerical examples concerning the optimization of a real-sized concrete cable-stayed bridge.

  11. Possibilites for Structural Improvements in the Design of Concrete Bridges

    OpenAIRE

    Spasojevic, Ana

    2006-01-01

    This paper presents the concept and the current state of a research investigating possibilities for further evolutions in medium span concrete road bridges. The main parameters of the study are the structural shape, the type of materials used and their disposition. The study will provide an optimisation of the design of various systems of concrete bridges, with the perspective of introducing new advanced cementitious materials, such as ultra high performance fibre reinforced concrete, UHPFC. ...

  12. Wind Resistant Design of Bridges in Japan Developments and Practices

    CERN Document Server

    Fujino, Yozo; Tanaka, Hiroshi

    2012-01-01

    For long-span bridges, wind action is a dominant factor in their safety and serviceability. A large number of long-span bridges have been built in Japan over the past 30 years, and tremendous amounts of research and technical development have been accomplished in wind resistant design. This book is a compilation of the results of active research and development. Wind resistant design standards generated in Japan are described in the first few chapters. Then comes information such as design wind speed, structural damping, wind tunnel tests, and analyses, which provide the basis of the design standards. Wind-induced vibrations and their control of girders, towers, cables, and other features are explained with examples of field measurements. Comprehensive listings of Japanese experience in vibration control are also presented. Because achieving particularly dynamic safety against wind is still not an easy task, these data and information will be valuable assets for the wind-engineering and bridge-engineering com...

  13. Influence of the new LRFD seismic guidelines on the design of bridges in Virginia

    OpenAIRE

    M.A. Widjaja; Roberts-Wollmann, Carin L.

    2004-01-01

    The Virginia Department of Transportation is currently using the AASHTO Standard Specifications for Highway Bridges, with some modifications, for its seismic highway bridge design. In April 2001, the Recommended LRFD Guidelines for the Seismic Design of Highway Bridges were published. The influence of the LRFD Guidelines on Virginia bridges was investigated by analyzing two existing bridges. The first bridge has prestressed concrete girders and is located in the Richmond area. The second brid...

  14. Research on Multidisciplinary Optimization Design of Bridge Crane

    Directory of Open Access Journals (Sweden)

    Tong Yifei

    2013-01-01

    Full Text Available Bridge crane is one of the most widely used cranes in our country, which is indispensable equipment for material conveying in the modern production. In this paper, the framework of multidisciplinary optimization for bridge crane is proposed. The presented research on crane multidisciplinary design technology for energy saving includes three levels, respectively: metal structures level, transmission design level, and electrical system design level. The shape optimal mathematical model of the crane is established for shape optimization design of metal structure level as well as size optimal mathematical model and topology optimal mathematical model of crane for topology optimization design of metal structure level is established. Finally, system-level multidisciplinary energy-saving optimization design of bridge crane is further carried out with energy-saving transmission design results feedback to energy-saving optimization design of metal structure. The optimization results show that structural optimization design can reduce total mass of crane greatly by using the finite element analysis and multidisciplinary optimization technology premised on the design requirements of cranes such as stiffness and strength; thus, energy-saving design can be achieved.

  15. Inclusive design: Bridging theory and practice

    NARCIS (Netherlands)

    Cremers, A.H.M.; Neerincx, M.A.; Jong, J.G.M. de

    2013-01-01

    Large groups in society lack the necessary skills to be sufficiently self-reliant and are in need of personal assistance. These groups could be supported by information and information technology (ICT), but only if this technology is designed to fit their (cognitive) abilities. Inclusive design theo

  16. Bridging the gap between instructional design and double loop learning

    NARCIS (Netherlands)

    Spoelstra, Howard; Matera, Maristella; Rusman, Ellen; Van Bruggen, Jan; Koper, Rob

    2006-01-01

    Spoelstra, H., Matera, M., Rusman, E., Van Bruggen, J., & Koper, R. (2006). Bridging the gap between instructional design and double loop learning. Proceedings of IV International Conference on Multimedia and Information and Communication Technologies in Education (m-ICTE2006). November, 22-25, 2006

  17. THE DESIGN OF VMEBUS BRIDGE CONTROLLER WITH SHARC BUS

    Institute of Scientific and Technical Information of China (English)

    Wang Min; Wu Shunjun; Su Tao

    2005-01-01

    Targeting at the high expense and inflexibility to realize VMEbus bridge controller by professional Integrated Circuit (IC), this paper presents a scheme of adopting CPLD/FPGA (Complicated Programmable Logic Device/Field Programmable Gate Array) to design bridge controller between VMEbus and local bus. SHARC DSP (Digital Signal Processor) bus is an example. It has functions of nearly entire master/slave interface of VMEbus, and can act as DMA (Direct Memory Access) controller and perform block transfer in DMA or master processor initiative way without length limit. External circuit of the design is very simple. In comparison with special ICs, it has high performance to price ratio and can be easily applied to local buses of other processors with quite a little modification.

  18. Zinc Oxide Nanorod Based Ultraviolet Detectors with Wheatstone Bridge Design

    Science.gov (United States)

    Vasudevan, Arun

    This research work, for the first time, investigated metal semiconductor-metal (MSM) zine oxide (ZnO) nanorod based ultra-violet (UV) detectors having a Wheatstone bridge design with a high responsivity at room temperature and above, as well as a responsivity that was largely independent of the change in ambient conditions. The ZnO nanorods which acted as the sensing element of the detector were grown by a chemical growth technique. Studies were conducted to determine the effects on ZnO nanorod properties by varying the concentration of the chemicals used for the rod growth. These studies showed how the rod diameter and the deposition of ZnO nanorods from the solution was controlled by varying the concentration of the chemicals used for the rod growth. Conventional MSM UV detectors were fabricated with ZnO nanorods grown under optimized conditions to determine the dependence of UV response on electrode dimension and rod dimension. These studies gave insights into the dependence of UV response on the width of the electrode, spacing between the electrodes, density of the rod growth, and length and diameter of the rods. The UV responsivity was affected by varying the number of times the seed layer was spin coated, by varying the spin speed of seed layer coating and by varying the annealing temperature of the seed and rod. Based on these studies, optimum conditions for the fabrication of Wheatstone bridge UV ZnO nanorod detectors were determined. The Wheatstone bridge ZnO nanorod UV detectors were fabricated in three different configurations, namely, symmetric, asymmetric, and quasi-symmetric. The transient responses of the symmetric, asymmetric and quasi-symmetric configurations at room temperature and above showed how the response stability differed. At high temperature the responsivity of quasi-symmetric Wheatstone bridge detector configuration did not drop after saturation and the responsivity drifted by 17% to 25% from the room temperature response

  19. 紧水滩大桥桥型方案设计%The Bridge Type Design Scheme of Jinshuitan Bridge

    Institute of Scientific and Technical Information of China (English)

    杨成峰; 邱白

    2014-01-01

    This paper introduces the design scheme of bridge type of Jinshuitan Bridge, compares the three kinds of schemes of the deck concrete arch bridge, prestressed concrete T beams and prestressed concrete continuous rigid frame bridge, and gi-ves the relevant conclusions and recommendations. Its design experience can be used for reference in the professional design personnel.%本文介绍了紧水滩大桥的桥型方案设计,比较了上承式混凝土拱桥、预应力砼 T 梁及预应力砼连续刚构等三种桥型方案,并给出相关结论和建议。其设计经验可供专业设计人员参考。

  20. Life cycle and performance based seismic design of major bridges in China

    Institute of Scientific and Technical Information of China (English)

    FAN Lichu

    2007-01-01

    The idea of life cycle and performance based seismic design of major bridges is introduced.Based on the key components and non-key components of a bridge and the consideration of the inspectability,replaceability,reparability,controllability and retrofitability of the bridge components,different seismic design levels and expected performance objectives are suggested for the major bridges in China.The vulnerability analysis and progressive collapse analysis,as well as risk assessment,are also proposed to be the important issues to study in order to guide the seismic design of major bridges in the future.

  1. Preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge are described. Static per-formance of this new type of bridge is discussed. Compared with fully self-anchored cable-stayed bridge, its advantages in fin-ished state are summarized. Based on numerical calculation, effects of several structural parameters on static performance are presented.

  2. Non-Flutter Design Principle for long Span Bridges

    DEFF Research Database (Denmark)

    Johansson, Jens; Andersen, Michael Styrk; Starch Øvre, Michele

    The case of flutter on a sharp edged flat plate section model, with a height-to-width ratio of 1:10, has been investigated at four different torsional-to-vertical frequency ratios equal to 0.71, 0.88, 1.19 and 2.10. At a torsional-to-vertical frequency ratio of approximately 1.1 the flutter wind...... velocity for a thin airfoil shows an asymptotical behavior. In traditional bridge design the torsional-to-vertical frequency ratio is increased to obtain higher flutter wind velocities. In the present study, we investigate, what we will label the non-flutter design principle, in which the torsional......-to-vertical frequency ratio will deliberately be smaller than 1. Two cases with frequency ratios of 1.19 and 2.10 showed classical and torsional flutter, respectively. Within the maximum wind velocity obtainable in the wind tunnel the two cases with a frequency ratio below 1 did not show any sign of aerodynamic...

  3. Next generation seismic fragility curves for California bridges incorporating the evolution in seismic design philosophy

    Science.gov (United States)

    Ramanathan, Karthik Narayan

    Quantitative and qualitative assessment of the seismic risk to highway bridges is crucial in pre-earthquake planning, and post-earthquake response of transportation systems. Such assessments provide valuable knowledge about a number of principal effects of earthquakes such as traffic disruption of the overall highway system, impact on the regions’ economy and post-earthquake response and recovery, and more recently serve as measures to quantify resilience. Unlike previous work, this study captures unique bridge design attributes specific to California bridge classes along with their evolution over three significant design eras, separated by the historic 1971 San Fernando and 1989 Loma Prieta earthquakes (these events affected changes in bridge seismic design philosophy). This research developed next-generation fragility curves for four multispan concrete bridge classes by synthesizing new knowledge and emerging modeling capabilities, and by closely coordinating new and ongoing national research initiatives with expertise from bridge designers. A multi-phase framework was developed for generating fragility curves, which provides decision makers with essential tools for emergency response, design, planning, policy support, and maximizing investments in bridge retrofit. This framework encompasses generational changes in bridge design and construction details. Parameterized high-fidelity three-dimensional nonlinear analytical models are developed for the portfolios of bridge classes within different design eras. These models incorporate a wide range of geometric and material uncertainties, and their responses are characterized under seismic loadings. Fragility curves were then developed considering the vulnerability of multiple components and thereby help to quantify the performance of highway bridge networks and to study the impact of seismic design principles on the performance within a bridge class. This not only leads to the development of fragility relations

  4. Design of unballasted track bridges on Beijing--Tianjin intercity railway%Design of unballasted track bridges on Beijing--Tianjin intercity railway

    Institute of Scientific and Technical Information of China (English)

    Sun Shuli; Zhang Wenjian; Wang Zhaohu; Su Wei; Wu Cailan; Bu Qinghao

    2011-01-01

    Beijing--Tianjin intercity railway is the first newly-built passenger dedicated line with operating speed of 350 km/h in our country. During design, new ideas of bridge construction were carried out to ensure the requirements of safety, comfort and stability of the train under high-speed condition. At the same time, concepts of environmental adaptability, service to transportation and comprehensive benefits were observed. On the whole line, long-bridge schemes were adopted and the most advanced technologies of unballasted track were utilized on bridges, the length of which accounts for 87.7 % of the total line. The success of design and construction of the bridges on this rail has accu- mulated valuable experience for high-speed railway construction on a large scale in the future, and made it a marking, demonstrating, and model project to follow.

  5. Slab- type Bridge Widening Design%板式桥梁加宽设计

    Institute of Scientific and Technical Information of China (English)

    焦彦利

    2012-01-01

    Taking a 3 - 20m medium bridge of Zhangshi Expressway as an example, problems needing atten- tions, selection of widening scheme and design in old bridge widening design are elaborated, providing references for widening design of similar bridges.%以张石高速公路3—20m中桥为例,对旧桥加宽设计中应该注意的问题、加宽方案的选择及其设计进行了阐述,为同类型桥梁的加宽设计提供参考。

  6. Designing of support zones of concrete bridges to withstand action of static and dynamic load

    Directory of Open Access Journals (Sweden)

    Gligorijević Milan

    2010-01-01

    Full Text Available In the paper are presented some of the acquired experiences in designing and construction of bridge structures in several countries, with a special attention to the analysis of support zones and expansion joints behavior of a number of road bridges. During destruction or damage of bridges, there is a small probability, but still there, that the human lives might be endangered (Kobe, Japan 17th January 1995; what is likely, however, is that it will be very difficult to help the injured in the region. Considering that the characteristics of removal of supports has a great influence on the behavior of the entire bridge structure, the design of support joints and connections must be paid due attention. In the recent decades, efforts are made to enhance research of all engineering structure, and thus the bridge structures and their weak points.

  7. Aesthetic design of bridges; Kyoryo ni okeru keikan sekkei no rekishi

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, H. [Kyushu Institute of Technology, Kitakyushu (Japan)

    1995-01-01

    The present paper outlines the bridge design in harmony with both ambient and natural environments. The condition which the bridge must clear has its two phases, i.e., `rational phase` focused on the practical utility to be managed by the engineering and `sensible phase` for the aesthetic achievement. The profile and scenery of bridge are based on the perfect teleology to engineer and process them by taking the influence into consideration on the mental phase. The beauty of bridge belongs to a category of technical beauty converting the technical product into an aesthetic object. The technical beauty is composed of `formal beauty` (The composition of all different members forms the beauty of harmony.), `functional beauty` (All different members under tension generate the dynamic beauty.) and `harmony with the environment`. For the harmony with the environment, what is taken into consideration is the steel, concrete and other material feeling, type of bridge adaptable to the environment, and color good for the environment. The following three methods are applied to the combination of bridge and environment: elimination method to vaguely immerse the bridge in the environment. Accentuation method to select the bridge as a main element of scenery. Harmonization method to harmonize the bridge with the environment. 21 refs., 14 figs.

  8. Designing for Anxiety Therapy, Bridging Clinical and Non-Clinical

    DEFF Research Database (Denmark)

    Bertelsen, Olav Wedege; Kramp, Gunnar

    2012-01-01

    In this position paper we discuss, in terms of the concept of boundary objects, how a mobile application, the MIKAT.app, bridge between clinical intervention in anxiety therapy, and life and coping strategies outside the clinic and across phases of being a person suffering from, or having suffered...... from anxiety. Thereby, we hope to provide a counterpoint in the discussion on illness trajectories....

  9. Computational design of donor-bridge-acceptor systems exhibiting pronounced quantum interference effects.

    Science.gov (United States)

    Gorczak, Natalie; Renaud, Nicolas; Galan, Elena; Eelkema, Rienk; Siebbeles, Laurens D A; Grozema, Ferdinand C

    2016-03-01

    Quantum interference is a well-known phenomenon that dictates charge transport properties of single molecule junctions. However, reports on quantum interference in donor-bridge-acceptor molecules are scarce. This might be due to the difficulties in meeting the conditions for the presence of quantum interference in a donor-bridge-acceptor system. The electronic coupling between the donor, bridge, and acceptor moieties must be weak in order to ensure localised initial and final states for charge transfer. Yet, it must be strong enough to allow all bridge orbitals to mediate charge transfer. We present the computational route to the design of a donor-bridge-acceptor molecule that features the right balance between these contradicting requirements and exhibits pronounced interference effects.

  10. Biaxial Behavior of Ultra-High Performance Concrete and Untreated UHPC Waffle Slab Bridge Deck Design and Testing

    OpenAIRE

    D'Alessandro, Kacie Caple

    2013-01-01

    Ultra-high performance concrete (UHPC) was evaluated as a potential material for future bridge deck designs. Material characterization tests took place to identify potential challenges in mixing, placing, and curing UHPC. Biaxial testing was performed to evaluate behavior of UHPC in combined tension and compression stress states. A UHPC bridge deck was designed to perform similarly to a conventional concrete bridge deck, and a single unit bridge deck section was tested to evaluate the desi...

  11. Extension of direct displacement-based design methodology for bridges to account for higher mode effects

    OpenAIRE

    Kappos, A. J.; Gkatzogias, K.I.; Gidaris, I.G.

    2013-01-01

    An improvement is suggested to the direct displacement-based design (DDBD) procedure for bridges to account for higher mode effects, the key idea being not only the proper prediction of a target-displacement profile through the effective mode shape (EMS) method (wherein all significant modes are considered), but also the proper definition of the corresponding peak structural response. The proposed methodology is then applied to an actual concrete bridge wherein the different pier heights and ...

  12. Effects of surface design on aerodynamic forces of iced bridge cables

    DEFF Research Database (Denmark)

    Koss, Holger

    2014-01-01

    In recent years the relevance of ice accretion for wind-induced vibration of structural bridge cables has been recognised and became a subject of research in bridge engineering. Full-scale monitoring and observation indicate that light precipitation at moderate low temperatures between zero and -5......°C may lead to large amplitude vibrations of bridge cables under wind action. For the prediction of aerodynamic instability quasi-steady models have been developed estimating the cable response magnitude based on structural properties and aerodynamic force coefficients for drag, lift and torsion....... The determination of these force coefficients require a proper simulation of the ice layer occurring under the specific climatic conditions, favouring real ice accretion over simplified artificial reproduction. The work presented in this paper was performed to study whether the design of bridge cable surface...

  13. The design philosophy and bridge's technical innovation of Hong Kong- Zhuhai-Macao Bridge

    Institute of Scientific and Technical Information of China (English)

    Meng Fanchao; Liu Minghu; Wu Weisheng; Zhang Gejun; Zhang Liang

    2014-01-01

    This article introduces the project overview, construction goal and design philosophy of Hong Kong- Zhuhai-Macao Bridge. Based on large scale, factory production, standardization and assemble line, the innova- tive concept is taken as the general principle for design with the emphasis on description of the new material, new technology, new construction method and new equipment used in the design. The application of innovative technology has provided a solid foundation and favorable guarantee for project quality and design service life

  14. Research on key technologies in design of middle pylon of Taizhou Bridge

    Institute of Scientific and Technical Information of China (English)

    Ji Lin

    2012-01-01

    At the middle pylon of a three-pylon two-span suspension bridge, the effect of unbalanced loads on the adjacent spans may result in a series of technical bottlenecks in design, such as stability and anti-slippage between saddles and main cables. This article presents the researches conducted on structure selection and behavior characteristics of middle pylon, interaction mechanism between main cables and saddles and their anti-slippage safety performance, elastic and plastic stability analysis and safety assessment of steel middle pylon, and fatigue design load and method for steel pylon of Taizhou Bridge. According to the research results, a longitudinal inverted Y shape steel middle pylon is used in design, effectively solving many technical difficulties, and this type of pylon has become a suitable middle pylon structural form for many three-ovlon two-soan susoension bridges.

  15. Multi-objective optimization design of bridge piers with hybrid heuristic algorithms

    Institute of Scientific and Technical Information of China (English)

    Francisco J. MARTINEZ-MARTIN; Femando GONZALEZ-VIDOSA; Antonio HOSPITALER; Victor YEPES

    2012-01-01

    This paper describes one approach to the design of reinforced concrete (RC) bridge piers,using a three-hybrid multiobjective simulated annealing (SA) algorithm with a neighborhood move based on the mutation operator from the genetic algorithms (GAs),namely MOSAMO1,MOSAMO2 and MOSAMO3.The procedure is applied to three objective functions:the economic cost,the reinforcing steel congestion and the embedded CO2 emissions.Additional results for a random walk and a descent local search multi-objective algorithm are presented.The evaluation of solutions follows the Spanish Code for structural concrete.The methodology was applied to a typical bridge pier of 23,97 m in height.This example involved 110 design variables.Results indicate that algorithm MOSAMO2 outperforms other algorithms regarding the definition of Pareto fronts.Further,the proposed procedure will help structural engineers to enhance their bridge pier designs.

  16. Designing a second language bridging course for university students

    Directory of Open Access Journals (Sweden)

    Carol A. Puhl

    2013-02-01

    Full Text Available The increasing number of students, especially black students, enrolling at university and needing to study in a medium of instruction which is not their mother tongue has underlined the need for additional language preparation as one way to reduce the failure and dropout rate. A possible solution is a bridging course aimed at developing academic language competencies to enable students to cope with communicative demands of their chosen course. An effective bridging course must take into account the requirements of the chosen institution and course, the level of student competency already achieved, and the actual student needs. These needs are divided into three areas: cognitive, which includes communicative macro-language skills and problem-solving skills; affective which includes self-confidence, acceptance of responsibility, and motivation; and behavioural, which includes cross-cultural competencies. Issues include duration of the course, the extent to which the course catersfor special purposes, and the didactic strategies employed. Three further considerations are the influence on the course of sponsors from business and industry, the academic level of the course, and effective evaluation methods. Die toenemende aantal studente, vera/ swart studente, wat aan 'n universiteit registreer waar die onderrigmedium nie hul moedertaal is nie, noodsaak bykomende taalvoorbereiding in 'n poging om die druip- en uitsaksyfer te verminder. Een moontlike oplossing is 'n oorbruggingskursus wat gemik is op die ontwikkeling van akademiese taalvermoens om studente in staat te stel om die kommunikatiewe eise van hul gekose kursus die hoof te bied. 'n Effektiewe oorbruggingskursus moet die volgende faktore in ag nee m: die vereistes van die gekose inrigting en kursus, die vaardigheidsvlak wat die student a/reeds bereik het sowel as die werklike studentebehoeftes. Hierdie behoeftes word in drie kategoriee verdeel: kognitief - wat kommunikatiewe makro

  17. Design and construction of the Aoba bridge; Aoba ohashi no keikaku to seko

    Energy Technology Data Exchange (ETDEWEB)

    Kuroki, H.; Wakamatsu, T. [Miyazaki Prefectural Government Office, Miyazaki (Japan); Akizuki, T. [P.S. Corp., Tokyo (Japan); Uchida, H. [Oriental Construction Co. Ltd., Tokyo (Japan)

    1997-05-30

    This paper describes the design and construction of a ferro-concrete fixed arch bridge (Aoba Bridge) in Takachiho Town, Miyazaki Prefecture. The bridge face height is 100 m above the river bed, wherein, since constructing roads for the construction is impossible near the site, and considerations were given on the scenic viewpoint, the bridge took a structure to stride the valley with a single span. The construction is characterized by adopting a construction method using truss and assembled arch simultaneously, and a cantilever overhanging erection using special large mobile erection vehicles. An optimum arrangement length in the simultaneous construction method was discussed on the length of the assembled arch. Since the site is in the quasi-national park where there is a promenade to enjoy nature under the bridge, excavation was carried out by using blasting and drilling machines simultaneously paying attention not to drop excavated rock lumps into the valley. Because the structure system makes extremely complicated changes from one time to another during the erection, the safety of construction was ensured by measuring stress and deformation in each construction phase and comparing the measurements with the planned values. Dynamic analyses and vibration tests were also carried out in each phase. The bridge was completed in December 1996 requiring four years without causing a single problem. The simultaneous truss and assembled arch using construction method was demonstrated for the first time in the world. 8 refs., 29 figs., 7 tabs.

  18. Optimum design of bridges with superelastic-friction base isolators against near-field earthquakes

    Science.gov (United States)

    Ozbulut, Osman E.; Hurlebaus, Stefan

    2010-04-01

    The seismic response of a multi-span continuous bridge isolated with novel superelastic-friction base isolator (S-FBI) is investigated under near-field earthquakes. The isolation system consists of a flat steel-Teflon sliding bearing and a superelastic NiTi shape memory alloy (SMA) device. Sliding bearings limit the maximum seismic forces transmitted to the superstructure to a certain value that is a function of friction coefficient of sliding interface. Superelastic SMA device provides restoring capability to the isolation system together with additional damping characteristics. The key design parameters of an S-FBI system are the natural period of the isolated, yielding displacement of SMA device, and the friction coefficient of the sliding bearings. The goal of this study is to obtain optimal values for each design parameter by performing sensitivity analyses of the isolated bridge. First, a three-span continuous bridge is modeled as a two-degrees-of-freedom with S-FBI system. A neuro-fuzzy model is used to capture rate-dependent nonlinear behavior of SMA device. A time-dependent method which employs wavelets to adjust accelerograms to match a target response spectrum with minimum changes on the other characteristics of ground motions is used to generate ground motions used in the simulations. Then, a set of nonlinear time history analyses of the isolated bridge is performed. The variation of the peak response quantities of the isolated bridge is shown as a function of design parameters. Also, the influence of temperature variations on the effectiveness of S-FBI system is evaluated. The results show that the optimum design of the isolated bridge with S-FBI system can be achieved by a judicious specification of design parameters.

  19. Design for minimizing fracture risk of all-ceramic cantilever dental bridge.

    Science.gov (United States)

    Zhang, Zhongpu; Zhou, Shiwei; Li, Eric; Li, Wei; Swain, Michael V; Li, Qing

    2015-01-01

    Minimization of the peak stresses and fracture incidence induced by mastication function is considered critical in design of all-ceramic dental restorations, especially for cantilever fixed partial dentures (FPDs). The focus of this study is on developing a mechanically-sound optimal design for all-ceramic cantilever dental bridge in a posterior region. The topology optimization procedure in association with Extended Finite Element Method (XFEM) is implemented here to search for the best possible distribution of porcelain and zirconia materials in the bridge structure. The designs with different volume fractions of zirconia are considered. The results show that this new methodology is capable of improving FPD design by minimizing incidence of crack in comparison with the initial design. Potentially, it provides dental technicians with a new design tool to develop mechanically sound cantilever fixed partial dentures for more complicated clinical situation. PMID:26405963

  20. Design of Main Bridge of Hanbei River Jingling Bridge%汉北河竟陵大桥主桥连续梁设计

    Institute of Scientific and Technical Information of China (English)

    严少波

    2014-01-01

    汉北河竟陵大桥主桥是一座为7跨预应力混凝土连续箱梁桥,桥跨布置为40 m+5×70 m+40 m。结合该桥的设计过程,探讨了该桥的技术标准、结构设计、结构计算、耐久性设计和主要施工方法,从材料、构造措施和施工工艺等方面进行了设计以保证大桥的使用寿命。%Hanbei River Jingling Bridge is a seven span prestressed concrete continuous box girder bridge with the bridge spans arrangement of 40 m+5×70 m+40 m.In accordance with the process of the design of the bridge,this paper discusses the technical standards,structure design,structure calculation,durability design and the main con-struction method.The durability of the bridge is appropriately designed by the rational utilization of materials and structural formation so as to eventually ensure the long-term service life of the bridge.

  1. A new design of SMES coil for bridging instantaneous voltage dips

    Energy Technology Data Exchange (ETDEWEB)

    Kurusu, T; Ono, M; Ogata, H; Tosaka, T; Senda, I; Nomura, S [Toshiba Corporation, 2-4, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan)

    2006-06-01

    This paper describes a new design concept of SMES coil for bridging instantaneous dips and some experimental results. The technical key point of this work is the design of a NbTi coil composed of a monolith NbTi/Cu wire for DC application. In order to cover the disadvantages of the monolith wire, some solutions have been proposed and tested using a fullscale test coil. Experimental results show the validity of the design concept of the SMES coil.

  2. Scaled down model design of shaking table test of Taizhou Bridge

    Institute of Scientific and Technical Information of China (English)

    Yan Jukao; Han Lei; Zhao Yi; Peng Tianbo

    2012-01-01

    Taizhou Bridge is the first kilometer level three-pylon two-span suspension bridge in the world and the structural complexity has significant effects on the seismic performance of the bridge. Shaking table test of Taizhou Bridge is arranged to investigate the effects of non-uniform ground motion input, collision between main and side spans and optimal seismic structural system. It' s very important and difficult to design and manufacture the scaled down model of Taizhou Bridge used during the shaking table test. The key point is that the girder and pylons are very hard to be manufactured if the similarity ratio is strictly followed. Based on the finite element method (FEM) analysis, a simplified scaled down model is designed and the bending stiffness of the girder and pylon are strictly simulated, and the torsion stiffness and axial stiffness are not strictly simulated. The inner forces and displacements of critical sections, points of simplified model and theoretical model are compared by FEM analysis, and it' s found out that the difference between the seismic responses is relatively small. So, the simplified model can be used to conduct the shaking table test by the FEM verification.

  3. High Frequency AC Inductor Analysis and Design for Dual Active Bridge (DAB) Converters

    DEFF Research Database (Denmark)

    Zhang, Zhe; Andersen, Michael A. E.

    2016-01-01

    The dual active bridge (DAB) converter is an isolated bidirectional dc-dc topology which is the most critical part for the power conversion systems such as solid-state transformers (SST). This paper focuses on analysis and design of high frequency ac inductors which are the power interfacing...

  4. Study Based on Bridge Health Monitoring System on Multihazard Load Combinations of Earthquake and Truck Loads for Bridge Design in the Southeast Coastal Areas of China

    Directory of Open Access Journals (Sweden)

    Dezhang Sun

    2015-01-01

    Full Text Available Similar to American LRFD Bridge Design Specifications, the current Chinese bridge design code is fully calibrated against gravity load and live load. Earthquake load is generally considered alone and has its own methodology, however, which is not covered in the code in a consistent probability-based fashion. Earthquake load and truck load are the main loads considered in the basis of bridge design in more than 70% of seismic areas in China. They are random processes, and their combination is the main subject of this paper. Seismic characteristics of southeast coastal areas of China are discussed and an earthquake probability curve is calculated through seismic risk analysis. Using measured truck load data from a Bridge Health Monitoring System, the multimodal characteristics of truck load are analyzed and a probability model for a time interval t is obtained by fitting results and reliability theory. Then, a methodology is presented to combine earthquake load and truck load on a probabilistic basis. To illustrate this method, truck load and earthquake load combinations are used. Results conceptually illustrate that truck load and earthquake load are not dominant in southeast coastal areas of China, but the effect of their combination is. This methodology quantitatively demonstrates that the design is controlled by truck load in most ranges; that is, truck load is more important to bridge design in the region.

  5. Construction and Design of Post-Tensioned Pearl-Chain Bridges using SL-Technology

    DEFF Research Database (Denmark)

    Halding, Philip Skov

    2016-01-01

    a filling layer of lower stiffness above the arches to level the road surface. The present Ph.D. thesis is part of a larger development project about Pearl‐Chain Bridges funded by Innovationsfonden. The project also included another Ph.D. study about the developed materials used in Pearl‐Chain Bridges......, and numerical modelling. Despite of high levels of normal force in PC‐Bridges, the result showed that a Mesnager inspired hinge type had a response similar to what was predicted in the literature. A specially designed saddle bearing also had elastic and plastic rotational resistance, but this hinge type......) A test to fracture to observe the ductility in the system, and fracture type. The collapse occurred after two plastic hinges were formed in the 3/8, and 5/8 points of the span. Several warnings signs were observed when approaching the maximum loading....

  6. Damage investigation of girder bridges under the Wenchuan earthquake and corresponding seismic design recommendations

    Institute of Scientific and Technical Information of China (English)

    Li Jianzhong; Peng Tianbo; Xu yan

    2008-01-01

    An investigation of girder bridges on National Highway 213 and the Doujiangyan-Wenchuan expressway after the Wenchuan earthquake showed that typical types of damage included:span collapses due to unseating at expansion joints;shear key failure;and damage of the expansion joint due to the slide-induced large relative displacement between the bottom of the girder and the top of the laminated-rubber bearing.This slide,however,can actually act as a form of isolation for the substructure,and as a result,the piers and foundation of most of the bridges on state route 213 suffered minor damage.The exception was the Baihua Bridge,which suffered severe damage.Corresponding seismic design recommendations are presented based on this investigation.

  7. Landscape Design Dialogue. Bridging the gap between knowledge and action

    NARCIS (Netherlands)

    Jonge, de J.M.; Valk, van der A.J.J.

    2010-01-01

    Spatial planners and landscape architects do not excel in theory development. The authors, being a practicing landscape architect-planner and a planning scholar, explore new roads to a middle range theory of landscape design and planning. Building on theories-in-use in regional planning practice the

  8. Bridging Translation by Improving Preclinical Study Design in AKI.

    Science.gov (United States)

    de Caestecker, Mark; Humphreys, Ben D; Liu, Kathleen D; Fissell, William H; Cerda, Jorge; Nolin, Thomas D; Askenazi, David; Mour, Girish; Harrell, Frank E; Pullen, Nick; Okusa, Mark D; Faubel, Sarah

    2015-12-01

    Despite extensive research, no therapeutic interventions have been shown to prevent AKI, accelerate recovery of AKI, or reduce progression of AKI to CKD in patients. This failure in translation has led investigators to speculate that the animal models being used do not predict therapeutic responses in humans. Although this issue continues to be debated, an important concern that has not been addressed is whether improvements in preclinical study design can be identified that might also increase the likelihood of translating basic AKI research into clinical practice using the current models. In this review, we have taken an evidence-based approach to identify common weaknesses in study design and reporting in preclinical AKI research that may contribute to the poor translatability of the findings. We focused on use of N-acetylcysteine or sodium bicarbonate for the prevention of contrast-induced AKI and use of erythropoietin for the prevention of AKI, two therapeutic approaches that have been extensively studied in clinical trials. On the basis of our findings, we identified five areas for improvement in preclinical study design and reporting. These suggested and preliminary guidelines may help improve the quality of preclinical research for AKI drug development.

  9. The Virtual Design Team: Designing Project Organizations as Engineers Design Bridges

    Directory of Open Access Journals (Sweden)

    Raymond E. Levitt

    2012-08-01

    Full Text Available This paper reports on a 20-year program of research intended to advance the theory and practice of organization design for projects from its current status as an art practiced by a handful of consultants worldwide, based on their intuition and tacit knowledge, to: (1 an “organizational engineering” craft, practiced by a new generation of organizational designers; and (2 an attractive and complementary platform for new modes of “virtual synthetic organization theory research.” The paper begins with a real-life scenario that provided the motivation for developing the Virtual Design Team (VDT, an agent-based project organizational simulation tool to help managers design the work processes and organization of project teams engaged in large, semi-routine but complex and fast-paced projects. The paper sets out the underlying philosophy, representation, reasoning, and validation of VDT, and it concludes with suggestions for future research on computational modeling for organization design to extend the frontiers of organizational micro-contingency theory and expand the range of applicability and usefulness of design tools for project organizations and supply-chain networks based on this theory.

  10. The ReflecTable: Bridging the Gap between Theory and Practice in Design Education

    DEFF Research Database (Denmark)

    Hook, Jonathan; Hjermitslev, Thomas; Iversen, Ole Sejer;

    The ReflecTable is a digital learning environment that explores how design games and video-led reflection might be combined to bridge the gap between the theoretical and practical components of design education. The concept seeks to leverage the qualities of exploratory design games and video...... to inspire design students to critically reflect upon the relationship between their evolving design practices and the theories and techniques they are taught in lectures, by allowing them to capture, review and reflect upon short videos of a design game. In this paper, we present the ReflecTable design...... and nine studies conducted during the course of its development. The studies suggest that the ReflecTable has the potential to support design students in understanding how theoretical concepts and methods relate to different design situations and their own evolving design practices....

  11. The design philosophy and bridge’s technical innovation of Hong Kong-Zhuhai-Macao Bridge

    Institute of Scientific and Technical Information of China (English)

    Meng Fanchao; Liu Minghu; Wu Weisheng; Zhang Gejun; Zhang Liang

    2014-01-01

    This article introduces the project overview,construction goal and design philosophy of Hong Kong-Zhuhai-Macao Bridge. Based on large scale,factory production,standardization and assemble line,the innova-tive concept is taken as the general principle for design with the emphasis on description of the new material, new technology,new construction method and new equipment used in the design. The application of innovative technology has provided a solid foundation and favorable guarantee for project quality and design service life.

  12. Simulation and Reasonable Design of Bridge Steel Fenders to Reduce Ship Impacts

    Institute of Scientific and Technical Information of China (English)

    OU Bifeng; WANG Junjie

    2006-01-01

    Steel fenders are increasingly used for ship-impact resistance structures in the design of navigable bridges.As an important approach to investigating this anti-impact structure effectiveness to reduce influences of vessel impact,simulation analyses are still not perfect yet.So this paper is intended to discuss several issues related to ship collision simulations,including steel constitutive relationship,connections between steel box and pile cap,contacts definition and friction consideration,and the determination of impact waterlines and angles.Consequently based on two examples of ship-steel fender-bridge structure systems,some conclusions about effectiveness and design of fenders to reduce ship impact are drawn.

  13. Reduction of Bridge Construction and Maintenance Costs through Coupled Geotechnical and Structural Design of Integral Abutment Bridges

    OpenAIRE

    Frosch, Robert J; Bobet, Antonio; Khasawneh, Yazen

    2014-01-01

    Elimination expansion joints in the superstructure of integral abutment bridges offers the advantage of reducing the initial and life cycle costs of the structure. However, such elimination may have an adverse effect on the displacement demand at the pile-abutment connection and on the earth pressures on the abutment wall due to the thermal expansion/contraction cycles of the bridge. These adverse effects have resulted in regulations that impose restrictions on the maximum length and skew ang...

  14. Optimal and sequential design for bridge regression with application in organic chemistry

    OpenAIRE

    Carnaby, Sarah

    2011-01-01

    This thesis presents and applies methods for the design and analysis of experiments for a family of coefficient shrinkage methods, known collectively as bridge regression, with emphasis on the two special cases of ridge regression and the lasso. The application is the problem of understanding and predicting the melting point of small molecule organic compounds using chemical descriptors. Experiments typically have a large number of predictors compared to the number of observations, and hig...

  15. Life cycle assessment of a railway bridge: comparison of two superstructure designs

    DEFF Research Database (Denmark)

    Du, Guangli; Karoumi, Raid

    2011-01-01

    database. Results show that the fixed-slab bridge option has a better environmental performance than the ballasted design due to the ease of maintenances. The initial material manufacture stage is responsible for the largest environmental burden, while the impacts from the construction machinery...... and material transportations are ignorable. Sensitivity analysis illustrates the maintenance scenario planning and steel recycling have the significant influence on the final results other than the traffic disturbances....

  16. Proof Testing a Bridge Deck Design with Glass Fiber Reinforced Polymer Bars as Top Mat of Reinforcement

    OpenAIRE

    Jason K. Cawrse; Roberts-Wollmann, Carin L.

    2003-01-01

    The primary objective of this project was to test a full-scale prototype of a bridge deck design containing glass fiber reinforced polymer (GFRP) bars as the top mat of reinforcement. The test deck mimics the design of the deck of one span of the new bridge over Gills Creek on Rt. 668 in Franklin County, Virginia. The purpose of the tests was to verify the deck design and provide assurance that the deck will behave as expected. Aspects of the behavior of the bridge deck, such as failure load,...

  17. Bridging operation and design. The encounter between practical and discipline-based knowledge in offshore platform design

    Energy Technology Data Exchange (ETDEWEB)

    Husemoen, Mette Suzanne

    1997-12-31

    This thesis investigates the relationship between operations and design and the design process, taking as case studies the two new platforms of Phillips Petroleum Company Norway on Ekofisk II, the Ekofisk 2/4 X drilling and wellhead platform and the Ekofisk 2/4 J processing and transportation platform. The emphasis has been on how to take into account operational experience in design. The two research questions are: (1) Are operations and design two communities-of-practice based on different kinds of knowledge?, and (2) What are the conditions for bridging knowledge in operations and design? From the theory reviewed and the field data presented the study concludes that physical closeness and integration of operations and design personnel, experience from the other community-of-practice, and mutual sympathy, trust, and respect, are important factors in bridging knowledge of the operations and design communities-of-practice and creating innovative solutions in design which transcend the existing knowledge in operations and design. 66 refs., 28 figs., 8 tabs.

  18. Design of steel box girder for Taizhou Yangtze River Highway Bridge

    Institute of Scientific and Technical Information of China (English)

    Ding Lei; Shan Hongwei; Zhou Qing; Zheng Benhui

    2011-01-01

    Taizhou Yangtze River Highway Bridge is the first three-pylon two-span suspension bridge in China. The maingirder adopts flat steamline steel closed box girder which has well wind-resistant capability and is technically mature besides beautiful appearance. Straight web plates of the steel box girder in longitudinal direction are proposed in order to ensure the integrity of the steel box girder, and to keep the stress of the steel box girder continuous in the middle pylon,as well as to reduce the gradient of the middle pylon columns. The cross section of the box girder has one box with three cells. Solid-web diaphragm plate with good integrity and high torsional stiffness is adopted. The lifting lugs are utilized in the anchors of suspender cable. In this paper, selection of the cross section of the steel box girder, the general structure design, local structure design and main structure calculation results of Taizhou Yangtze River Bridge are introduced emphatically.

  19. The Principle of the Micro-Electronic Neural Bridge and a Prototype System Design.

    Science.gov (United States)

    Huang, Zong-Hao; Wang, Zhi-Gong; Lu, Xiao-Ying; Li, Wen-Yuan; Zhou, Yu-Xuan; Shen, Xiao-Yan; Zhao, Xin-Tai

    2016-01-01

    The micro-electronic neural bridge (MENB) aims to rebuild lost motor function of paralyzed humans by routing movement-related signals from the brain, around the damage part in the spinal cord, to the external effectors. This study focused on the prototype system design of the MENB, including the principle of the MENB, the neural signal detecting circuit and the functional electrical stimulation (FES) circuit design, and the spike detecting and sorting algorithm. In this study, we developed a novel improved amplitude threshold spike detecting method based on variable forward difference threshold for both training and bridging phase. The discrete wavelet transform (DWT), a new level feature coefficient selection method based on Lilliefors test, and the k-means clustering method based on Mahalanobis distance were used for spike sorting. A real-time online spike detecting and sorting algorithm based on DWT and Euclidean distance was also implemented for the bridging phase. Tested by the data sets available at Caltech, in the training phase, the average sensitivity, specificity, and clustering accuracies are 99.43%, 97.83%, and 95.45%, respectively. Validated by the three-fold cross-validation method, the average sensitivity, specificity, and classification accuracy are 99.43%, 97.70%, and 96.46%, respectively.

  20. Design and stability analysis of continuous skew tied-arch bridge over Bin Jiang River

    Institute of Scientific and Technical Information of China (English)

    Jiancheng YU; Hao TONG; Wei HUANG

    2008-01-01

    A tied arch bridge without wind bracing was built over the Bin Jiang River, with oblique angle of 20°. Its main design details are described and mechanical performances are analyzed. The stability analytical types are also introduced and the first elastic stability theory is used. A space finite element model has been built to analyze the stability performances in both construction and operation stages for single span or continuous, orthogonal or oblique bridge. The influence of stiffness of the end crossbeam is also analyzed. The result shows that out-plane buckling occur for a rigid tie and similar no matter whether it is single span or continuous and orthogonal or oblique. When there are more and stronger inner crossbeams, the influence of the end crossbeams on arch stability becomes unremarkable.

  1. 淦河桥梁方案设计研究%Design and Research on Bridge Scheme of Gan River

    Institute of Scientific and Technical Information of China (English)

    蔡忠华

    2016-01-01

    Following the principal of applicable,economical,safe and beautiful and taking the bridge crossing Gan River in Jingui west road in Xianning City as the engineering background,four types of bridge design schemes are introduced,namely simple supported girder bridge,continuous girder bridge,through tied-arch bridge,and cable-stayed bridge without backstays.The tied arch bridge is chosen as the recommended proposal by taking bridge design,landscape feature,construction feasibil-ity and economy into comprehensive consideration.%遵循“适用、经济、安全、美观”的桥梁设计基本原则,以咸宁市金桂西路跨淦河大桥为工程背景,提供了4种桥梁设计方案:无背索斜拉桥,预应力混凝土连续梁桥、预应力混凝土简支 T梁桥、下承式系杆拱桥。综合考虑论证桥梁构造设计、景观特色、施工可行性和经济性等因素,选取下承式系杆拱桥作为推荐方案。

  2. Design of portable bridge of material access on level 8 m

    International Nuclear Information System (INIS)

    Base on the planning to increase of the working capability of the rabbit system facility, using the design of mentioned portable bridge on material access has been done. Using the designed installation, the transportation of the middle and high active samples from the isotop cell to the scanning room will be easy to be done. The design has been done by using the maximum actual load, and also the chosen steel shape dimension compliance with ASTM standard. The installation required 2 pieces of W 6 x 12 steel beam by 111.82 inches in length, 4 pieces W 6 x 12 steel beam by 47.25'' in length and a piece of steel plate by 111.82'' x 47.25'' x 0.394''. This paper concluded that this design is feasible to be fabricated

  3. Design of Portable Bridge of Material Access on 8 m Level

    International Nuclear Information System (INIS)

    Base on the planning to increase of the working capability of the working capability of the rabbit system facility, the design of mentioned portable bridge on access has been done. Using the designed installation the transportation of the middle and high active samples from the isotop cell to the scanning room will be easy to be done. The design has been done by using the maximum actual load. Determination of maximum actual load, determination of maximum actual load, and also the chosen steel shape dimension compliance with ASTM standard. The installation required 2 peaces of W 6 x 12 steel beam by 111.82 inches in length, 4 peaces W 6 x 12 steel beam by 47.25in length and a peace of steel plate by 111.82x 47.25x 0,394. This paper concluded that this design is feasible to be fabricated

  4. Design of Main Bridge of Shuangyudao Bridge in Zhangzhou Development Zone%漳州开发区双鱼岛大桥主桥设计

    Institute of Scientific and Technical Information of China (English)

    陶小兰; 李涛; 姚建军

    2013-01-01

    Main bridge of Shuangyudao Bridge in Fujian Zhangzhou Development Zone is a 36m +2×66m +36m cable-stayed bridge with single pylon and double cable planes, and its girders are fish-belly prestressed concrete continuous box girders, cable pylon is twin-dolphin gate-typed steel tower, piers are in elliptic shape and bored pile foundation is adopted. This paper introduces design of all major structures, analyzes stresses on girder, cable pylon, stayed cable and steel anchor box of the bridge by establishing finite-element integral and local computational models and introduces its construction scheme.%福建省漳州开发区双鱼岛大桥主桥为36 m+2×66 m+36 m独塔双索面斜拉桥,主梁采用鱼腹式预应力混凝土连续箱梁,索塔为双鱼门型钢塔,桥墩为椭圆造型,采用钻孔灌注桩基础.介绍该桥各主要结构的设计,通过建立有限元整体计算模型及局部计算模型对该桥主梁、索塔、斜拉索、钢锚箱的受力进行分析并对其施工方案进行介绍.

  5. Vibration mitigation of a bridge cable using a nonlinear energy sink: design and experiment

    Directory of Open Access Journals (Sweden)

    Weiss Mathieu

    2015-01-01

    Full Text Available This work deals with the design and experiment of a cubic nonlinear energy sink (NES for horizontal vibration mitigation of a bridge cable. Modal analysis of horizontal linear modes of the cable is experimentally performed using accelerometers and displacement sensors. A theoretical simplified 2-dof model of the coupled cable-NES system is used to analytically design the NES by mean of multi-time scale systems behaviours and detection its invariant manifold, equilibrium and singular points which stand for periodic and strongly modulated regimes, respectively. Numerical integration is used to confirm the efficiency of the designed NES for the system under step release excitation. Then, the prototype system is built using geometrical cubic nonlinearity as the potential of the NES. Efficiency of the prototype system for mitigation of horizontal vibrations of the cable under for step release and forced excitations is experimentally demonstrated.

  6. Biaxial Behavior of Ultra-High Performance Concrete and Untreated UHPC Waffle Slab Bridge Deck Design and Testing

    Science.gov (United States)

    D'Alessandro, Kacie Caple

    Ultra-high performance concrete (UHPC) was evaluated as a potential material for future bridge deck designs. Material characterization tests took place to identify potential challenges in mixing, placing, and curing UHPC. Biaxial testing was performed to evaluate behavior of UHPC in combined tension and compression stress states. A UHPC bridge deck was designed to perform similarly to a conventional concrete bridge deck, and a single unit bridge deck section was tested to evaluate the design methods used for untreated UHPC. Material tests identified challenges with placing UHPC. A specified compressive strength was determined for structural design using untreated UHPC, which was identified as a cost-effective alternative to steam treated UHPC. UHPC was tested in biaxial tension-compression stress states. A biaxial test method was developed for UHPC to directly apply tension and compression. The influence of both curing method and fiber orientation were evaluated. The failure envelope developed for untreated UHPC with random fiber orientation was suggested as a conservative estimate for future analysis of UHPC. Digital image correlation was also evaluated as a means to estimate surface strains of UHPC, and recommendations are provided to improve consistency in future tests using DIC methods. A preliminary bridge deck design was completed for untreated UHPC and using established material models. Prestressing steel was used as primary reinforcement in the transverse direction. Preliminary testing was used to evaluate three different placement scenarios, and results showed that fiber settling was a potential placement problem resulting in reduced tensile strength. The UHPC bridge deck was redesigned to incorporate preliminary test results, and two single unit bridge deck sections were tested to evaluate the incorporated design methods for both upside down and right-side up placement techniques. Test results showed that the applied design methods would be conservative

  7. 道路桥梁设计隐患分析%Analysis of Road and Bridge Design Hazard

    Institute of Scientific and Technical Information of China (English)

    崔巍

    2015-01-01

    作为道路桥梁工程施工建设过程中最关键的环节,道路桥梁的设计质量直接影响其施工建设的整体质量。道路桥梁的设计问题可从耐用性和安全性考虑,设计时,应充分考虑桥梁设计、建设和使用中各类影响道路桥梁安全的因素,同时对道路桥梁设计中存在的问题提出解决对策。注重设计的合理性和科学性,在保证工期进度的同时,充分保证道路桥梁的整体质量。%As the roads and bridges,the most crucial steps in the process of engineering construction, road and bridge design quality directly affect the overall quality of construction.Road and bridge design problems from the durability and safety consideration,the design,should give full consideration to bridge design,construction and use of all kinds of factors affecting the safety of roads and bridges,as well as the problems of road and bridge design countermeasures are put forward. Pay attention to the rationality and scientific nature of design,during the guarantee period of progress at the same time,fully guarantee the overall quality of the roads and bridges.

  8. Designing and Inhabiting Virtual Environments: Bridging the gap between physical and virtual

    Directory of Open Access Journals (Sweden)

    Matevž Juvančič

    2012-01-01

    Full Text Available Bringing the trilogy of the Erasmus intensive programme together in 2010, the Faculty of Architecture organised the third workshop in the series “Designing and Inhabiting Virtual Environments - DIVE”, addressing an elusive issue: “Bridging the gap between the physical and virtual” with the reference site of Križanke. During the 10-day intensive workshop, the participants developed a theoretical discussion based on a series of lectures, and afterwards pursued analyses of the reference site and designed spatial interventions with an emphasis on respecting the fragile nature of the site. From the very beginning to the end of their work, the participants analysed the boundaries between physical and virtual reality, examined the pros and cons of each, and sought possible integrations of both entities within a seamless and effective conceptual and actual representation.

  9. Design and Characterization of a Peptide Mimotope of the HIV-1 gp120 Bridging Sheet

    Directory of Open Access Journals (Sweden)

    Guido Poli

    2012-05-01

    Full Text Available The Bridging Sheet domain of HIV-1 gp120 is highly conserved among the HIV-1 strains and allows HIV-1 binding to host cells via the HIV-1 coreceptors. Further, the bridging sheet domain is a major target to neutralize HIV-1 infection. We rationally designed four linear peptide epitopes that mimic the three-dimensional structure of bridging sheet by using molecular modeling. Chemically synthesized peptides BS3 and BS4 showed a fair degree of antigenicity when tested in ELISA with IgG purified from HIV+ broadly neutralizing sera while the production of synthetic peptides BS1 and BS2 failed due to their high degree of hydrophobicity. To overcome this limitation, we linked all four BS peptides to the COOH-terminus of GST protein to test both their antigenicity and immunogenicity. Only the BS1 peptide showed good antigenicity; however, no envelope specific antibodies were elicited upon mice immunization. Therefore we performed further analyses by linking BS1 peptide to the NH2-terminus of the E2 scaffold from the Geobacillus Stearothermophylus PDH complex. The E2-BS1 fusion peptide showed good antigenic results, however only one immunized rabbit elicited good antibody titers towards both the monomeric and oligomeric viral envelope glycoprotein (Env. In addition, moderate neutralizing antibodies response was elicited against two HIV-1 clade B and one clade C primary isolates. These preliminary data validate the peptide mimotope approach as a promising tool to obtain an effective HIV-1 vaccine.

  10. 上承式拱梁组合桥设计%Design of combined deck type arch bridge

    Institute of Scientific and Technical Information of China (English)

    严国香

    2012-01-01

    结合某桥的工程地理位置及沿河景观要求,对该桥的结构设计特点、构造与施工要点等进行了简要介绍,目前该桥运营情况良好,并取得了一定的经济、社会效益,为同类型桥梁施工积累宝贵经验。%This paper synthesized the engineering geographic location and river landscape requirements of a bridge,simply introduced the structure design features,structure and construction key points of this bridge,present the bridge was operating in good condition,and achieved certain economic,social effect,accumulated valuable experience for the same type bridge construction.

  11. Influence of the Non-linear Effects in the Design of Viscous Dampers for Bridge Cables

    OpenAIRE

    Acar, Yalda; Jingstål, Pontus

    2014-01-01

    In this master thesis the performance of external viscous dampers attached to cables in cable-stayed bridges have been studied. A comparison has been performed between a linear and a non-linear cable model. The comparison was carried out for two bridge cables, one from the Dubrovnik Bridge and the other from the Normandie Bridge. The performance of the dampers have been measured in terms of maximum achieved damping ratio and minimum amplitude of vibration. The analysis was performed using the...

  12. 乌苏大桥主桥上部结构设计与计算%Design and Calculation of Superstructure of Main Bridge of Wusu Bridge

    Institute of Scientific and Technical Information of China (English)

    康晋; 肖海珠; 徐伟

    2011-01-01

    The main bridge of the Wusu Bridge is a single pylon and single cable plane cablestayed bridge with span arrangement (140+140) m and with a structural system of rigid fixity of the pylon, pier and girder. A summarized account of the design and calculation of the superstructure of the bridge is presented herewith. The main girder of the bridge is a composite girder with long cantilevers, the central part of the girder is designed as a two-cell and single-box steel girder and the steel cantilever at each side of the girder is the variable depth I-beam and is provided wiht a trough stringer at the far side, which are all topped with 25 cm thick concrete deck slabs connected with the girder via shearing studs. The part of the main girder close to the pylon is designed as a prestressed concrete box girder to facilitate the fixity of the girder with the pylon. The pylon is the single column pylon, 117 m in height. The stay cables, made up of low relaxation galvanized high strength parallel steel wire strands, are of the harp pattern cable plane arranged in the central alignment of the bridge deck. The finite element software MIDAS Civil 2006 and the SCDS programme are employed to calculate and analyze structure of the bridge. The results of the calculation and analysis indicate that the static, stability and dynamic characteristics of the bridge can meet the requirements in the relevant codes.%乌苏大桥主桥为独塔单索面斜拉桥,跨径布置为(140+140) m,采用塔、墩、梁固结体系,综述该桥上部结构设计与计算.主梁为带大挑臂的钢箱结合梁,中间钢箱梁采用单箱双室截面,两侧钢挑臂为变高度工字形梁,挑臂端部设槽形小纵梁;混凝土桥面板厚25 cm,与钢梁通过剪力钉连接;塔根部主梁采用预应力混凝土箱梁,以方便与桥塔固结;桥塔采用独柱式塔,高117 m;斜拉索为竖琴形中央平行索面布置,采用低松弛镀锌高强度平行钢丝束.采用有限元软件MIDAS Civil

  13. Optimum Design of Multilayer Asphalt Surfacing Systems for Orthotropic Steel Deck Bridges

    NARCIS (Netherlands)

    Li, J.

    2015-01-01

    Orthotropic steel decks are widely utilized in long span bridges, movable bridges and shorter span road and rail bridges due to their favourable properties. These properties are low deadweight, large plastic reserves in case of overload and aesthetic advantages. Nowadays, more than 1000 orthotropic

  14. Asset Management Business Model for Design, Realization, and Maintenance of Fibre Reinforced Polymer Bridges

    Directory of Open Access Journals (Sweden)

    Rizal Sebastian

    2013-01-01

    Full Text Available This paper particularly addresses the market implementation of Fibre Reinforced Polymer (FRP for bridges. It presents the concept of demand and supply chain innovation as being investigated within two ongoing European collaborative research projects (FP7 titled Trans-IND and PANTURA. FRP has emerged as a real alternative structural material based on various sustainability considerations, among others the reduced life-cycle cost due to less maintenance needs, longer lifetime, and easiness to repair, replace, or recycle the components. The Trans-IND research project aims to develop and demonstrate new industrialized processes to use FRP for civil infrastructure projects at a large scale. In order to be cost effective, a new value-chain strategy for the design, realization, and maintenance of FRP bridges is required to replace the fragmented supply chain and the one-off approach to a construction project. This paper focuses on the development of new business models based on asset management strategy, which covers the entire demand and supply chains. Research on new business models is supported by the insight into the market and regulatory frameworks in different EU countries. This is based on field surveys across the EU that have been carried out as a part of the Trans-IND and PANTURA collaborative research projects.

  15. Chiral linker-bridged bis-N-heterocyclic carbenes: design, synthesis, palladium complexes, and catalytic properties.

    Science.gov (United States)

    Zhang, Dao; He, Yu; Tang, Junkai

    2016-08-01

    A series of chiral bis(benzimidazolium) salts 10-19 with (1R,2R)-cyclohexene, (1R,2R)-diphenylethylene and (aR)-binaphthylene linkers have been designed and synthesized in 30-94% yield. Ten chiral bis(NHC) palladium complexes 20-28 have been synthesized and characterized by NMR, HRMS, elemental analysis and further confirmed by X-ray single crystal analysis. These bis(NHC)-Pd complexes showed obviously different catalytic properties in the asymmetric Suzuki-Miyaura coupling reactions. The (1R,2R)-cyclohexene-bridged bis(NHC)-Pd complex, (R,R)-23, achieved the highest yield of 90%, while complex (aR)-28, with a binaphthylene linker, showed the best enantioselectivity of 60 ee%. The structural analysis of these complexes suggested that such difference of catalytic performance has a close relationship with their coordination surroundings around metal centres. PMID:27230553

  16. Computational Protein Engineering: Bridging the Gap between Rational Design and Laboratory Evolution

    Directory of Open Access Journals (Sweden)

    Shina Caroline Lynn Kamerlin

    2012-09-01

    Full Text Available Enzymes are tremendously proficient catalysts, which can be used as extracellular catalysts for a whole host of processes, from chemical synthesis to the generation of novel biofuels. For them to be more amenable to the needs of biotechnology, however, it is often necessary to be able to manipulate their physico-chemical properties in an efficient and streamlined manner, and, ideally, to be able to train them to catalyze completely new reactions. Recent years have seen an explosion of interest in different approaches to achieve this, both in the laboratory, and in silico. There remains, however, a gap between current approaches to computational enzyme design, which have primarily focused on the early stages of the design process, and laboratory evolution, which is an extremely powerful tool for enzyme redesign, but will always be limited by the vastness of sequence space combined with the low frequency for desirable mutations. This review discusses different approaches towards computational enzyme design and demonstrates how combining newly developed screening approaches that can rapidly predict potential mutation “hotspots” with approaches that can quantitatively and reliably dissect the catalytic step can bridge the gap that currently exists between computational enzyme design and laboratory evolution studies.

  17. Highway bridge seismic design: summary of FHWA/MCEER project on seismic vulnerability of new highway construction

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Federal Highway Administration (FHWA) sponsored a large, multi-year project conducted by theMultidisciplinary Center for Earthquake Engineering Research (MCEER) titled "Seismic Vulnerability of New HighwayConstruction" (MCEER Project 112), which was completed in 1998. MCEER coordinated the work of many researchers, whoperformed studies on the seismic design and vulnerability analysis of highway bridges, tunnels, and retaining structures.Extensive research was conducted to provide revisions and improvements to current design and detailing approaches andnational design specifications for highway bridges. The program included both analytical and experimental studies, andaddressed seismic hazard exposure and ground motion input for the U.S. highway system; foundation design and soil behavior;structural importance, analysis, and response; structural design issues and details; and structural design criteria.

  18. Topological design of all-ceramic dental bridges for enhancing fracture resistance.

    Science.gov (United States)

    Zhang, Zhongpu; Chen, Junning; Li, Eric; Li, Wei; Swain, Michael; Li, Qing

    2016-06-01

    Layered all-ceramic systems have been increasingly adopted in major dental prostheses. However, ceramics are inherently brittle, and they often subject to premature failure under high occlusion forces especially in the posterior region. This study aimed to develop mechanically sound novel topological designs for all-ceramic dental bridges by minimizing the fracture incidence under given loading conditions. A bi-directional evolutionary structural optimization (BESO) technique is implemented within the extended finite element method (XFEM) framework. Extended finite element method allows modeling crack initiation and propagation inside all-ceramic restoration systems. Following this, BESO searches the optimum distribution of two different ceramic materials, namely porcelain and zirconia, for minimizing fracture incidence. A performance index, as per a ratio of peak tensile stress to material strength, is used as a design objective. In this study, the novel XFEM based BESO topology optimization significantly improved structural strength by minimizing performance index for suppressing fracture incidence in the structures. As expected, the fracture resistance and factor of safety of fixed partial dentures structure increased upon redistributing zirconia and porcelain in the optimal topological configuration. Dental CAD/CAM systems and the emerging 3D printing technology were commercially available to facilitate implementation of such a computational design, exhibiting considerable potential for clinical application in the future. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26444905

  19. On the Performance of Super-Long Integral Abutment Bridges: Parametric Analyses and Design Optimization

    OpenAIRE

    Lan, Cheng

    2012-01-01

    The concept of "integral abutment bridge" has recently become a topic of remarka-ble interest among bridge engineers, not only for newly built bridges but also during refurbishment processes. The system constituted by the substructure and the superstructure can achieve a composite action responding as a single structural unit; the elimination of expansion joint and bearings on the abutments, greatly reduce the construction and maintenance costs. To maximize the benefits from integral abutment...

  20. 连续刚构桥的设计分析%Analysis on Design of Continuous Rigid-Frame Bridge

    Institute of Scientific and Technical Information of China (English)

    米春阳

    2014-01-01

    The continuous rigid frame bridge, due to its advantages of beautiful structure, reasonable force, smooth-comfortable driving, easy maintenance and low cost, is widely used in bridge construction. This paper, taking the B1 bridge design of Hong Kong Liangtang/Heung Yuen Wai Boundary Control Point Site Formation and Infrastructure Works, the project of Contract 3 as an example, presents the ideas, theories, methods of design and construction process for the continuous rigid-frame bridge, discuss-es the main parts of the design details, to achieve the goal of reasonable design and structural safety.%连续刚构桥,由于其结构美观、受力合理、行车平稳舒适、易养护、费用低等优点,在桥梁工程建设中被广泛采用。以香港莲塘/香园围口岸-土地平整及基础建设工程-合约3项目的B1桥设计为例,对连续刚构桥设计思路、理论及处理方法、施工流程进行阐述,讨论设计中的重要细节及要点,以达到设计合理和结构安全的目的。

  1. Conceptual Design of Continuous Bridges%连续梁桥的抗震能力概念设计

    Institute of Scientific and Technical Information of China (English)

    贺金海; 王江波; 袁万城

    2012-01-01

    Continuous bridges have a widely application in the construction of transportation and they are very important to guarantee the flow of transportation network. But, for the reason of geographic condition, route and other non-seismic factors, the seismic systems of bridges are not reasonable and the anti-seismic capability is not sufficient. Based on the basic design philosophies, conceptual design of bridges can get a good seismic performance. This paper, considering the seismic damage of bridges, puts forward the basic philosophies of conceptual design, and combined with the engineering example, the paper discusses the importance and effectiveness of seismic conceptual design, providing some helpful references for the seismic design of the continuous bridges.%连续梁桥应用广泛,对确保交通网络畅通具有举足轻重的作用.通常情况下由于地形条件、路线走向等非抗震因素影响致使桥梁结构的抗震体系不合理,导致抗震能力不足.基于抗震设计的基本原则,对桥梁结构灵活处理能有效获得良好的抗震体系.结合地震中桥梁震害以及工程经验等,探讨与分析了抗震概念设计的基本原则,并通过实例分析说明了抗震概念设计能从根本上提高桥梁的抗震性能,为实现经济有效的抗震设防提供有益参考.

  2. Study in the design and manufacture process of the elastic cable anchor box in steel box girder of Taizhou Bridge

    Institute of Scientific and Technical Information of China (English)

    Gu Bifeng; Chen Ce; Ding Lei

    2011-01-01

    Taizhou Yangtze River Highway Bridge is a large span suspension bridge with three pylons. The elastic cables are installed to connect the steel tower and the steel box girder. The constraints can increase the safety coefficient of the middle saddle, and improve the stress conditions of the middle pylon and decrease the deflection in the middle of the main girder, as well as the longitudinal displacement of the main girder caused by live loads. The anchorage boxes of the elastic cable are installed in the wind fairing outside the vertical web plate of the box girder. Two anchor boxes form a pair and are arranged parallelly. Eight anchor boxes are installed in the bridge. In this paper, the design scheme and the technical difficulties in manufacturing are briefly discussed with the precision control techniques.

  3. 乌溪江大桥方案设计%Scheme Design of Wuxijiang Bridge

    Institute of Scientific and Technical Information of China (English)

    张红星; 刘德宝; 余茂峰

    2011-01-01

    乌溪江大桥为浙江省遂昌县西南部跨越乌溪江水库的一座特大型桥梁.根据桥梁建设条件、景观、造价等因素,拟定了钢管混凝土拱桥、劲性骨架混凝土拱桥、连续刚构三种桥型方案.通过综合比较,确定钢管混凝土拱桥作为推荐桥型方案.%Wuxijiang Bridge is a long span bridge across Wuxijiang Reservoir in the southwest of Suichang County, Zhejiang Province. On the basis of the conditions of bridge construction, landscape, cost and other factors, three shemes of concrete-filled steel pipe arch bridge, concrete arch bridge with stiff skeleton, continuous rigid frame bridge are put forward. Through comprehensive comparison, concrete-filled steel pipe arch bridge is determined as recommended bridge type.

  4. Structural behaviour and design criteria of under-deck cable-stayed bridges subjected to seismic action

    OpenAIRE

    Cámara Casado, Alfredo; Ruiz Teran, Ana M.; Stafford, Peter J.

    2012-01-01

    SUMMARY: Under-deck cable-stayed bridges are very effective structural systems for which the strong contribution of the stay cables under live loading allows for the design of very slender decks for persistent and transient loading scenarios. Their behaviour when subjected to seismic excitation is investigated herein and a set of design criteria are presented that relate to the type and arrangement of bearings, the number and configuration of struts, and the transverse distribution of stay ca...

  5. A Discussion on Xiqiaoshuidao Road Bridge Design Plan%西樵水道公路桥设计方案探讨

    Institute of Scientific and Technical Information of China (English)

    卢维华

    2009-01-01

    随着国家基础建设的快速发展,公路桥的设计日趋复杂.文章以西樵水道公路桥为例,从桥位选择、桥型确定、过河桥孔布置、主桥结构体系比选等方面介绍和评述了西樵水道公路桥设计方案的可行性.%With the rapid development of the capital construction,road bridge design becomes more and more complex. Taking the Xiqiaoshuidao highway bridge as example,the article introduces and evaluates the feasibility of the design plan from the aspects of bridge position and bridge type selection,bridge opening arrangement and main bridge structure ratio.

  6. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...... to quantify the different structural configurations and allows a preliminary optimization of the main structure.Included are the most recent advances in structural design, corrosion protection of cables, aerodynamic safety, and erection procedures....

  7. 剖析山区桩柱式桥梁受力的设计%Analysis on mountainous pile type bridge force design

    Institute of Scientific and Technical Information of China (English)

    任佳贝

    2016-01-01

    概述了山区桥梁设计应遵守的基本原则,从桥梁外业勘测、下部结构选择、上部构造设计等方面,对桩柱式桥梁受力的设计进行了论述,总结了桥梁设计中的注意事项,从而提高山区公路桥梁的安全性及适用性。%This paper summarized the basic principles of mountain bridge design,from the bridge field survey,lower part structure selection, upper structure design and other aspects,discussed the pile type bridge force design,summarized the matters needing attention in bridge design, so as to improve the safety and applicability of mountainous highway bridges.

  8. Design of stiffening girder for Taizhou Bridge%泰州大桥加劲梁设计

    Institute of Scientific and Technical Information of China (English)

    单宏伟; 丁磊; 周青

    2012-01-01

    泰州大桥是世界上首座超千米的三塔两跨悬索桥,加劲梁结构体系复杂并有其独特之处.在设计过程中根据三塔悬索桥的结构特点,加劲梁构造细节设计在润扬大桥的基础上做了较大改进和创新,介绍了加劲梁的结构体系、构造设计、结构计算以及梁段的加工制造和架设情况.%Taizhou Bridge is the first three-tower two-span suspension bridge with the main span over 1 000 m in the world. The structural system of the stiffening girder is complicated and unique. Improvement and innovation have been made in detailed structure design of the stiffening girder based on Runyang Bridge according to the structural character of three-pylon two-span suspension bridge. In this paper, the structural system, structure design, structure calculation, manufacturing and erection of the stiffening girder are introduced.

  9. Design and experimental verification of a new multi-functional bridge seismic isolation bearing

    Institute of Scientific and Technical Information of China (English)

    Chen-xi XING; Hao WANG; Ai-qun LI; Ji-rong WU

    2012-01-01

    A new multi-functional bridge seismic isolation bearing (MFBSIB) is designed and its mechanical model is developed in this paper.Combining an upper sliding device and a lower energy dispassion isolation device effectively,the new MFBSIB can adjust the deformation caused by temperature,vehicle breaks,and concrete creep,etc.,in addition to dissipating energy.The switch of ‘slide-isolation' is achieved and the efficiency of both upper and lower parts is validated through experiment with a model.The shear performance curve established in this paper is verified to be efficient in describing the mechanical characteristics of the bearing through experiment.It is proved through both numerical calculation and experimental analysis that the new MFBSIB is endowed with enough vertical rigidity,good energy dissipation ability,stable overall performance,and good realization in expected goals.Its performance is slightly influenced by shear stress,while affected by vertical pressure,loading frequency,slide limit,etc.,diversely.The results could provide reference for study and application of the new MFBSIB.

  10. Key Techniques for Design of Main Bridge of Songhua River Highway-railway Bridge in Harbin-Bei’an Railway%滨北线松花江公铁两用桥主桥设计关键技术

    Institute of Scientific and Technical Information of China (English)

    续宗宝

    2016-01-01

    The Songhua River Highway-railway Bridge of Harbin-Bei’an Railway is the first modern highway-railway bridge in Chinese cold area,and the main bridge is a continuous steel truss beam bridge with a main span of 144 m.In the paper, the general idea of the main bridge design is introduced.Firstly,combined with the environment of the bridge site,the main bridge structure is studied according to the comparison and analysis.Secondly,the structure durability is studied through test under the ultra-low temperature environment.Finally,the truss height,truss width,bridge deck system and materials etc.,are adopted according to a series of researches.The obtained design results have great theoretical and prac-tical values for the design of similar type bridge.%滨北线松花江公铁两用桥是我国第一座严寒地区修建的现代化公铁两用桥,主桥采用主跨144 m 连续钢桁梁桥。介绍了主桥结构设计的总体思路,并结合桥位处环境,通过比较及分析计算研究了主桥结构形式,并通过试验对超低温环境结构耐久性进行了相关研究,根据研究确定了适用于该桥特点的桁高、桁宽、桥面系、材质等设计要素。本桥设计对该地区同类型桥梁的设计具有重要的理论意义和工程实用价值。

  11. Soft-switching PWM full-bridge converters topologies, control, and design

    CERN Document Server

    Ruan, Xinbo

    2014-01-01

    Soft-switching PWM full-bridge converters have been widely used in medium-to-high power dc-dc conversions for topological simplicity, easy control and high efficiency. Early works on soft-switching PWM full-bridge converter by many researchers included various topologies and modulation strategies.  However, these works were scattered, and the relationship among these topologies and modulation strategies had not been revealed. This book intends to describe systematically the soft-switching techniques for pulse-width modulation (PWM) full-bridge converters, including the topologies, control and

  12. Patterns of HCI design and HCI design of patterns bridging HCI design and model-driven software engineering

    CERN Document Server

    Seffah, Ahmed

    2015-01-01

    As interactive systems are quickly becoming integral to our everyday lives, this book investigates how we can make these systems, from desktop and mobile apps to more wearable and immersive applications, more usable and maintainable by using HCI design patterns. It also examines how we can facilitate the reuse of design practices in the development lifecycle of multi-devices, multi-platforms and multi-contexts user interfaces. Effective design tools are provided for combining HCI design patterns and User Interface (UI) driven engineering to enhance design whilst differentiating between UI

  13. A comparative study between China and U.S. on seismic design philosophy and practice of a long span arch bridge

    Institute of Scientific and Technical Information of China (English)

    Xu Yan; George C Lee; Fan Lichu; Hu Shide

    2006-01-01

    This paper presents the first of a series of case studies on the seismic design of long span bridges (cablestayed bridges, suspension bridges and arch bridges) under a cooperative research project on seismic behavior and design of highway bridges between the State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University and the Multidisciplinary Center for Earthquake Engineering Research, University at Buffalo. The objective of this series of case studies is to examine the differences and similarities on the seismic design practice of long span bridges in China and the U.S., to identify research needs and to develop design guidelines beneficial to bridge engineers in both countries. Unlike short to medium span bridges, long span bridges are not included in most seismic design specifications, mainly because they are location dependent and structurally unique. In this paper, an available model of a steel tied half through arch bridge with a main span of 550m in China is discussed. Analysis is focused on comparisons of the seismic responses due to different ground motions. Seismic design criteria and seismic performance requirements for long span bridges in both countries were first introduced and compared, and then three near field earthquake records with large vertical components were selected as the excitations to examine the seismic behavior and seismic vulnerability of the bridge. Results show that (1) the selected near field ground motions cause larger responses to key components (critical sections) of the bridge (such as arch rib ends) with a maximum increase of more than twice those caused by the site specific ground motions; (2) piers, longitudinal girders and arch crowns are more vulnerable to vertical motions, especially their axial forces; and (3) large vertical components of near field ground motions may not significantly affect the bridge's internal forces provided that their peak acceleration spectra ordinates only appear at periods

  14. 张家口清水河商务大桥设计与施工%Design and construction of Qingshui river business bridge in Zhangjiakou

    Institute of Scientific and Technical Information of China (English)

    柴增铧; 齐钺

    2012-01-01

    Combining with the Qingshui river big bridge general situation, this paper introduced the main technical parameters of this bridge, general arrangement of bridge, main structure design and main points of construction, it has better traffic operation after the establishment, proved that the bridge design reasonably, so as to provide guidance for the same type bridge design.%结合清水河大桥概况,介绍了该桥的主要技术指标、桥梁总体布置、主要结构设计与施工要点,建成后通车运营良好,证明了本桥设计成功合理,从而为同类型桥梁设计提供指导。

  15. Idea of Design Scheme of Oujiang Bridge in Wenzhou City%温州瓯江大桥设计方案构思

    Institute of Scientific and Technical Information of China (English)

    罗嗣碧; 唐方清; 孔祥升; 杨华振

    2012-01-01

    Based on city bridge landscape requirements, a basket-type arch bridge scheme and a self anchored suspension bridge are presented for Oujiang Bridge. The two schemes are good fusion bridge located in natural environment. The basket type arch bridge scheme and the self-anchored suspension bridge scheme are in the top three on the bridge design competition at the same time. The projects and its landscape effect are introduced to provide the references for the same types of bridge landscape design.%基于城市桥梁的景观要求,对瓯江大桥提出了提篮式拱桥方案和自锚式悬索桥方案,两种方案均能很好地融合桥位处的自然环境.提篮式拱桥方案和高低塔自锚式悬索桥方案同时进入本桥方案竞赛的前三名.介绍了此方案的构思及其景观效果,为同类型的桥梁景观设计提供借鉴及参考.

  16. Design and parametric study on energy harvesting from bridge vibration using tuned dual-mass damper systems

    Science.gov (United States)

    Takeya, Kouichi; Sasaki, Eiichi; Kobayashi, Yusuke

    2016-01-01

    A bridge vibration energy harvester has been proposed in this paper using a tuned dual-mass damper system, named hereafter Tuned Mass Generator (TMG). A linear electromagnetic transducer has been applied to harvest and make use of the unused reserve of energy the aforementioned damper system absorbs. The benefits of using dual-mass systems over single-mass systems for power generation have been clarified according to the theory of vibrations. TMG parameters have been determined considering multi-domain parameters, and TMG has been tuned using a newly proposed parameter design method. Theoretical analysis results have shown that for effective energy harvesting, it is essential that TMG has robustness against uncertainties in bridge vibrations and tuning errors, and the proposed parameter design method for TMG has demonstrated this feature.

  17. Design for Huaxi Bridge in Highway around Guiyang City%贵阳环城高速公路花溪大桥设计

    Institute of Scientific and Technical Information of China (English)

    金令

    2012-01-01

    Huaxi Bridge is a super large bridge across above Huaxi reservoir in the south line of Guiyang City Highway. The main bridge, which is a 192 m half-through concrete-filled steel tube arch bridge with 29.3 m in full width ( bi-direction four lanes plus sidewalks) and 100 km/h design speed, is the key bridge and controlling project of the whole line. The author illustrates the general design situation of the bridge, including bridge-type selection, design parameters, structure details and construction methods. According to the situations at the bridge site, Huaxi Bridge is the first bridge using the technologies such as triangular space truss arch, cutting caisson foundation, self-compacting concrete-filled steel tube in Guizhou region, which can give some references for the same type of bridge constructions in mountainous karst area.%花溪大桥为贵阳环城高速公路南环线跨越花溪水库的一座特大型桥梁,主桥为192 m的中承式钢管混凝土拱桥,大桥全宽29.3 m(双向四车道+人行道),设计速度100 km/h,是全线重点桥梁和控制性工程.介绍该桥的总体设计情况,包括桥式选择、设计参数、构造细节、施工方法.根据桥址处的条件大桥在贵州地区首次采用了三角形空间桁架拱、挖井基础、自密实钢管混凝土等技术,对多山岩溶地区同类型桥梁建设具有参考意义.

  18. Experimental evaluation of the buckling phenomena in the new joint design for upper deck structure of a bridge

    Directory of Open Access Journals (Sweden)

    Solazzi L.

    2010-06-01

    Full Text Available This paper is concerned with the experimental mechanical analysis of a new design of a joint for a main components of a upper deck of a road bridge. These components are subject to the compression state stress induced by the weight and the load acting on the road. Each upper deck of a bridge (positioned on each side of the bridge is composed by four tubular structures that must be joint each together. The joint must to take in to account many aspects, for example that the length of each component is not the same (because, obviously, there is a mechanical tolerance. This phenomena induce different compression stress on each component and so is very important non only the critical buckling load but also the post buckling behaviour of the structure. It is very important that if a single tubular structure reaches the critical load of instability, it still has load capacity . This is to avoid that, in the case where a column reaches the instability, the entire load acting on a column increase the load on the remaining three. For this purpose many different geometrical solutions have been designed (elaborated by fem analyses and successively tested experimentally. This work reports the main experimental results on the best joint solution and how this increase the load capacity and the displacement respect to the solution without this flange.

  19. THE NON-LINEAR METHODS OF ANALYSIS IN MODERN DESIGNING (BY THE EXAMPLE OF GEOTECHNICS FACILITIES AND BRIDGES

    Directory of Open Access Journals (Sweden)

    N. N. Melnichuk

    2010-10-01

    Full Text Available Problem statement. Non-linear solutions are widely used within the framework of solution of the problems of development of the areas which were earlier unsuitable for construction (wetlands, slope areas; bases consisting of weak overwet soils.Results and conclusions. Design models and examples of practical implementa-tion of two groups of non-linear analysis in design of construction objects are considered. These are spatial deformation analysis of reinforced concrete decks of road bridges and elastoplastic numerical analysis of the bases, soil structures and structures interacting with soil structures.

  20. Design of Cable-Stayed Bridge of Caofeidian Industry Zone Bridge No.1%曹妃甸工业区1号桥斜拉桥设计

    Institute of Scientific and Technical Information of China (English)

    陈亮; 卢永成; 周伟翔; 邵长宇

    2011-01-01

    The Caofeidian Industry Zone Bridge No. 1 is composed of navigable span bridge, non-navigable span bridges and approach bridges and is located in the cold and strong earthquake region in the northern part of China. A summarized account of the design of the navigable span bridge of the bridge is presented herewith. In accordance with the construction conditions and landscape requirements, the navigable span bridge is designed as a single pylon and single cable plane cable-stayed bridge with span arrangement 2 X 138 m, the pylon is the column pylon in shape of boat sail. The anchorage zone in the pylon is the steel anchor box exposed outside the pylon. The main girder is the steel and concrete composite girder having three cells and a single box. The stay cables are made up of φ7 mm galvanized parallel steel wires and the foundation of the pylon pier is the group pile foundation. The research of seismic resistance of the bridge show that for a major single pylon cable-stayed bridge located in the strong earthquake region, the rigid fixity system of pylon, girder and pier should be possibly avoided in order to reduce seismic response of the bridge structure.%曹妃甸工业区1号桥位于北方寒冷强震区,由通航孔桥、非通航孔桥及引桥组成,综述该桥通航孔桥设计.根据建设条件及景观要求,通航孔桥为跨径2×138 m独塔单索面斜拉桥;桥塔为独柱形,造型为船帆式;索塔锚固区采用外露式钢锚箱方案;主梁采用单箱三室钢-混凝土箱形结合梁;斜拉索采用φ7 mm镀锌平行钢丝;桥塔墩采用群桩基础.抗震性能研究表明,强震区大型独塔斜拉桥应尽量避免采用塔、梁、墩固结体系,以减小桥梁结构的地震响应.

  1. Design of bridge crane girder strain acquisition system based on virtual instrument

    Directory of Open Access Journals (Sweden)

    Wenxue LIU

    Full Text Available Girder is an important part of the bridge crane, which is also the main force element. In order to prevent accidents, it is necessary to collect the bridge crane girder stress data to analyse the fatigue life. This paper constructs a bridge crane girder strain acquisition system. The hardware system consists of sensors, connectors, data acquisition cards, wireless data transmission groups, POE power and host computer. The software system consists of NI MAX to interface with the computer's NI hardware and software resources,and LabVIEW programming to display and storage the girder strain data. Through this system, positions and working days strain data acquisition for the 50/10 t bridge crane girder gets the key positions strain data. The results show that the girder strain data acquisition system runs stably, channel signals of acquisition task transmit accurately, and the terminal data stores competely, meeting the detection requirements, which provides an important data support for the subsequent fatigue analysis and accurate remaining service life prediction of the crane girder.

  2. Educational Game Design. Bridging the gab between computer based learning and experimental learning environments

    DEFF Research Database (Denmark)

    Andersen, Kristine

    2007-01-01

    Considering the rapidly growing amount of digital educational materials only few of them bridge the gab between experimental learning environments and computer based learning environments (Gardner, 1991). Observations from two cases in primary school and lower secondary school in the subject...

  3. Design and performance of an EMI filter to reduce conducted EMI in an isolated full bridge buck converter power supply

    Institute of Scientific and Technical Information of China (English)

    Abdolreza Esmaeli; SUN Li; ZHAO Ke; JIANG Bao-jun

    2005-01-01

    EMI Filter Design and Performance for isolated full bridge buck converter is developed in this paper.In order to design a high performance EMI filter, many issues need to be considered beforehand. Some important issues including accurate model of converter components, parasitic elements, its effect on EMI noise and impedance mismatch are included in this paper. A numerical prediction of EMI/EMC has the potential to evaluate EMI performances at the design stage and before prototyping. It can also help reduce the post-prototype EMC cost by minimizing late redesign and modifications of a design implementation. Saber simulator is used to analyze the EMI noises and EMI filter's performance. Conducted EMI noise measurement and EMI filter design of isolated full bridge buck converter has been achieved while successfully satisfying the FCC class B limits in the frequency range from 150 kHz to 30 MHz. Simulation results are compared with experimental data and the effectiveness of the EMI simulation approach is demonstrated.

  4. Design of the Main Bridge Steel Truss Girder of Xinglong Bridge%兴隆大桥主桥钢桁梁设计

    Institute of Scientific and Technical Information of China (English)

    杨文; 何耀炜

    2016-01-01

    下承式钢桁梁桥因其具有建筑高度低、施工速度快和结构轻巧简洁等优点,成为中等跨度公路桥梁中有竞争力的桥型。文中以兴隆大桥为依托,建立数学分析模型,对下承式钢桁梁桥结构的受力特性进行分析,并指出该类型桥梁施工的方法和技术要点。%The through steel truss girder bridge becomes a bridge type for medium span highway bridg-es with low building height,fast construction speed and the advantages of compact and simple struc-ture.Based on the Xinglong Bridge,a mathematical analysis model is established in this paper to ana-lyze the mechanical characteristics of the steel truss girder bridge,and the method and technical points of the bridge construction are pointed out.

  5. 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.

  6. Taizhou Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Taizhou Bridge lies between Taizhou, Zhenjiang and Changzhou City in Jiangsu Province. The total length of Taizhou Bridge is 62.088 kin. The whole line is designed by freeway codes with six lanes in two directions. The wholeinvestment is 9.37 billion RMB and the planned construction duration is 5.5 years. The main bridge crossing the Yangtze River is a continuous three-pylon two-span suspension bridge with the main span of 1 080 m. The bridge system is realized for the first time and ranks first in the world until now.

  7. Overall Design and Study of South and North Bridges of Xiazhang Sea-Crossing Bridge%厦漳跨海大桥南、北汊桥总体设计与研究

    Institute of Scientific and Technical Information of China (English)

    王福敏; 罗强; 李军

    2013-01-01

    厦漳跨海大桥主要由北汊桥、海门岛立交及收费服务区、南汊桥、海平立交四大部分组成,全长9.333 km.为适应复杂的自然与建设条件,对该桥桥位方案进行比选,并对项目中关键控制性工程(北汊主桥、南汊主桥)的桥型方案进行研究.经研究,最终确定北汊主桥采用主跨780m的五跨连续钢箱梁斜拉桥方案,南汊主桥采用主跨300 m的结合梁斜拉桥方案.针对项目中复杂的地质条件、高地震烈度和恶劣的风环境,分别采取设置适应性强的桩基础,对较差的桩基地质注浆;按抗震要求进行构造设计,在主桥塔梁处设置纵向阻尼器,引桥设置减隔震支座;北汊主桥采用一种翼型扶手栏杆、南汊主桥采用分流板抗风等措施进行处理.%The Xiazhang Sea-Crossing Bridge,totally 9.333 km long,is composed of four major parts of the north bridge,Haimen Island interchange and toll service area,south bridge and Haiping interchange.To accommodate the complicated natural and construction conditions of the bridge,the bridge site schemes were compared and the bridge type schemes for the critical control projects (the north and south main bridges) were studied.According to the study,it was finally determined that the 5-span continuous steel box girder cable-stayed bridge with a main span 780 m would be adopted for the north main bridge and the composite girder cable-stayed bridge with a main span 300 m would be adopted for the south main bridge.In consideration of the complicated geologic conditions,high intensity earthquake and harsh wind environment,the well adaptive pile foundations were respectively utilized.For the pile foundations at the locations with poor geology,the foundations would be grouted.The structures of the bridge were designed in compliance with the seismic resistance requirements.At the connections between the pylons and girders of the main bridges,the longitudinal dampers were arranged and on the piers

  8. Design and rationale of the HCC BRIDGE study in China: a longitudinal, multicenter cohort trial in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Qiao You-Lin

    2011-05-01

    Full Text Available Abstract Background More than 50% of the worldwide cases of hepatocellular carcinoma occur in China, and this malignancy currently represents the country's second leading cause of cancer death in cities and the leading cause in rural areas. Despite recent advances in the control and management of hepatocellular carcinoma within China, this disease remains a major health care issue. The global HCC BRIDGE study, designed to assess patterns of hepatocellular carcinoma therapy use and associated outcomes across real-world clinical practice, has recently been expanded as a national study in China, allowing a detailed analysis of hepatocellular carcinoma in this important country. Methods/Design The global HCC BRIDGE study is a multiregional longitudinal cohort trial including patients newly diagnosed with hepatocellular carcinoma between January 1, 2005, and June 30, 2011, who are receiving treatment for hepatocellular carcinoma via sites in the Asia-Pacific, European, and North American regions. The HCC BRIDGE China national study comprises the portion of the global HCC BRIDGE study conducted within mainland China. Patients will be followed from time of diagnosis of hepatocellular carcinoma (post-January 1, 2005 to time of death or December 31, 2011, whichever comes first. Data will be collected on demographic/clinical characteristics, relevant laboratory values, hepatocellular carcinoma/underlying liver disease treatment, tumor response, adverse events, hospitalizations, and overall survival. The primary study end point is overall survival; secondary end points are disease progression, treatment-limiting adverse events, and treatment failure. Results At the time of writing, 15 sites have selected for participation across all 7 traditional regions of China (North, North-East, East, South, South-West, North-West, and Central. The anticipated study population from the China national study is approximately 9000 patients. Discussion Findings from the

  9. AVES SDK: Bridging the Gap between Simulator and Flight Systems Designer

    OpenAIRE

    Gerlach, Torsten; Durak, Umut

    2015-01-01

    Developing and integrating a new concept in a flight simulator usually requires rigorous implementation and integration steps which involves various parties. German Aerospace Center (DLR) is developing and operating the Air Vehicle Simulator (AVES), and focusses on shortening the simulator implementation and integration lead time. This effort targets at bridging this gap by promoting the software infrastructure of the flight simulator as AVES Software Development Kit (SDK) for flight system d...

  10. Design and optimization of micro-semiconductor bridge used for solid propellant microthrusters array

    Science.gov (United States)

    Ru, Chengbo; Dai, Ji; Xu, Jianbing; Ye, Yinghua; Zhu, Peng; Shen, Ruiqi

    2016-06-01

    Igniter is the basic component of MEMS-based solid propellant microthrusters (SPM) array, which should response fast with low dissipated energy. To satisfy the requirements, micro-semiconductor bridge (MSCB) with dual V-angles contributing to the reduction of dissipated energy is introduced into the array. The electrical explosion characteristics of MSCB investigated under constant voltage, in the considerations of the limit of power supply in the micro/nanosatellite, are similar to those under capacitive discharge. The bridge was completely vaporized and burst into the hot plasma under high-level voltage. While under low-level voltage, the bridge was partly vaporized without detected plasma. The 3#SCB (90° V-angle) with the smallest power density resulting in the lowest applied voltage (12.0 V) and the 2#SCB with the smallest narrow width (Wmin) leading to the lowest average power (11.3 W) were chosen to the further optimization. The ignition tests were implemented to examine the ignition reliability of the contractible igniters, which were optimized to satisfy the voltage limitation with sufficient ignition capacity. The results show that the effective SCB with lowest dissipated power is the 3#-3SCB, which function within 100 μ under 7.0 V, and the average power below 5.0 W.

  11. Design of the Long-term Safety Monitoring System of Zhicheng Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The long-term safety monitoring system of Zhicheng Yangtze River Bridge was established in the principle of open information service and standardized systems engineering.The ADSL dynamic IP communication network established by using VPN technology and application of encryption technology,tunnel technology and user identification accreditation technology have made the system safer and more reliable.The system can fulfill real-time,regular and triggered signal collection according to needs and may give notice or alarm for the discovery of real-time failure.Monitored data can be collected and stored to provide reliable data for stipulating technical indicators for safety operation of the large-span railway bridges.The system,after its completion,can maintain its long-term stable running,take hold of the running condition of all locations of bridge under monitoring,evaluate the overall situation and life cycle,and make available the technical reserves for the Infrastructure Inspection Center of MOR.

  12. 钢桥面沥青铺装层设计要点分析%Analysis of the Notes about Design of the Steel Bridge Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      本文根据笔者多年的工作经验,从钢桥面沥青铺装设计的技术要求、桥面沥青铺层的结构和大跨径钢桥面沥青铺装三个方面,探讨了钢桥面沥青铺装层的设计要点。%In this article bases on years of work experience, discusses the design points of steel bridge asphalt pavement fr-om three aspects of the technical requirements of steel bridge asphalt pavement design, the structure of bridge asphalt over-lay and the large span steel bridge asphalt pavement.

  13. Optimum design of phase opposition disposition pulse width modulation logic circuit for switching seven level cascaded half bridge inverter

    Directory of Open Access Journals (Sweden)

    Nentawe Y. Goshwe

    2016-06-01

    Full Text Available Theevolution of multilevel inverters (MLIs has made it possible to extract power from direct current (DC sources to alternating current (AC power. This paper presents the design of a novel phase opposition disposition pulse width modulation scheme (PODPWM logic circuit for a conventional single phase seven level cascaded H-Bridge (CHB inverter using Matlab/Simulink. The minimum switching logic circuit for the single phase seven level CHB inverter was obtained by modeling the logic equations that could be used with any number of levels depending on the number of modulating and carrier signals involved. The reduction in total harmonic distortion (THD of the output voltage for the MLI using low switching frequency at different modulation indixes is also investigated. The logic equations have made it easier to design a PODPWM circuit for any CHB inverter and the logic gates designed gave an optimum THD value of 16.73 % at modulation index of 0.20.

  14. Differential mode EMI filter design for ultra high efficiency partial parallel isolated full-bridge boost converter

    DEFF Research Database (Denmark)

    Makda, Ishtiyaq Ahmed; Nymand, M.

    2013-01-01

    This paper presents a practical method to design a Differential Mode EMI filter for fuel cell powered isolated full bridge dc-dc boost converter. As the input voltage of such converter is inherently low with very high dc and ripple currents and since the EMI limits also does not change...... for such application, it calls for a carefully optimized EMI filter which is designed and implemented in this work. Moreover, the negative input impedance of the regulated converter is extremely low; well-designed filter damping branch is also included. Differential mode noise is analyzed analytically for a 3KW/400V...... boost converter. Simulation and experimental results are recorded and published. © 2013 IEEE....

  15. APPLICATION OF STEEL PIPE PILE LOADING TESTS TO DESIGN VERIFICATION OF FOUNDATION OF THE TOKYO GATE BRIDGE

    Science.gov (United States)

    Saitou, Yutaka; Kikuchi, Yoshiaki; Kusakabe, Osamu; Kiyomiya, Osamu; Yoneyama, Haruo; Kawakami, Taiji

    Steel sheet pipe pile foundations with large diameter steel pipe sheet pile were used for the foundation of the main pier of the Tokyo Gateway bridge. However, as for the large diameter steel pipe pile, the bearing mechanism including a pile tip plugging effect is still unclear due to lack of the practical examinations even though loading tests are performed on Trans-Tokyo Bay Highway. In the light of the foregoing problems, static pile loading tests both vertical and horizontal directions, a dynamic loading test, and cone penetration tests we re conducted for determining proper design parameters of the ground for the foundations. Design parameters were determined rationally based on the tests results. Rational design verification was obtained from this research.

  16. Integral Abutment and Jointless Bridges

    OpenAIRE

    Cristian-Claudiu Comisu

    2005-01-01

    Integral bridges, or integral abutment and jointless bridges, as they are more commonly known in the USA, are constructed without any movement joints between spans or between spans and abutments. Typically these bridges have stub-type abutments supported on piles and continuous bridge deck from one embankment to the other. Foundations are usually designed to be small and flexible to facilitate horizontal movement or rocking of the support. Integrally bridges are simple or multiple span ones t...

  17. Optimal Design of Concrete Tied Arch Bridge%混凝土系杆拱桥优化设计

    Institute of Scientific and Technical Information of China (English)

    乔建东; 吴慧山; 杨伟

    2015-01-01

    为探讨混凝土系杆拱桥的多参数优化设计方法,选取计算矢高、拱肋截面尺寸、系梁截面尺寸、吊杆面积和系梁纵向预应力筋数目作为设计变量,规范限值为约束条件,全桥总造价为目标函数,建立了混凝土系杆拱桥的优化模型;采用大型通用程序ANSYS和桥梁结构平面分析程序,结合混合整型序列二次规划法,混合编程求解优化模型.以某拱桥为工程背景,建立并求解优化模型,将优化结果与设计值进行比较.结果表明:系梁混凝土用量减少40.98%,拱肋混凝土用量减少23.81%,预应力钢筋数目减少28.23%,全桥材料总造价降低28.63%.%In order to investigate the multi-parameter optimal design method of concrete tied arch bridges,an optimal model was established. In this model,rise,cross section dimensions of arch ribs and tied beams,area of each suspender and number of pre-stressed steel bars in each hole are selected as the design variables,code values as the constraint conditions,and total cost of whole bridge as the objective function. A plane analysis program for bridge structure,the software ANSYS and the mix-integer sequence quadratic program method were used together to program and solve the optimal model. The optimal model was solved by taking an arch bridge as engineering background,the optimal results were compared with the design values. The comparison results show that the concrete consumptions of tied beams and arch ribs is respectively reduced by 40 . 98% and 23 . 81%,the number of pre-stressed steel bars is decreased by 28 . 23%,and the total material cost is cut by 28 . 63%.

  18. Railroad Bridges

    Data.gov (United States)

    Department of Homeland Security — Bridges-Rail in the United States According to The National Bridge Inspection Standards published in the Code of Federal Regulations (23 CFR 650.3), a bridge isA...

  19. 虎门二桥坭洲水道桥索塔结构设计及受力分析%Design and Analysis of Pylons of Nizhou Watercourse Bridge of Humen No. 2 Bridge

    Institute of Scientific and Technical Information of China (English)

    马玉全; 孙向东; 陈枝洪

    2014-01-01

    广东虎门二桥坭洲水道桥为主跨1688m 双塔非对称式两跨连续钢箱梁悬索桥,为世界上最大跨径的钢箱梁悬索桥,索塔采用门式钢筋混凝土结构,塔高260m,由下塔柱、下横梁、中塔柱、中横梁、上塔柱、上横梁组成。介绍了该桥索塔的设计思路和构造特点,并采用 MIDAS CIVIL 2012专业桥梁分析软件建立全桥三维空间杆系有限元模型,对索塔结构进行计算,结果表明塔柱及横梁的应力、强度均满足规范要求。%Nizhou Watercourse Bridge is an asymmetric continuous steel box girder suspension bridge with twin towers and a main span 1688m,which marks the largest span of steel box girder suspension bridge in the world. The pylons of the bridge are designed as the reinforced concrete structures with lowerlegs,lower tie beams,middlelegs,middle tie beams,upperlegs and upper tie beams,which contribute a total height of 260m. After presenting the design idea and structure characteristics of the pylon,in the paper,by means of the bridge comprehensive program MIDAS CIVIL 2012, the 3D frame structure finite element model for the whole bridge has been established,and the pylons structure has been calculated. The results show that the stress and strength of the pylons and the tie beams can meet the specifications re-quirements.

  20. 赵家沟大桥临时支架设计%Design of Temporary Support System for Zhaojiagou Bridge

    Institute of Scientific and Technical Information of China (English)

    孙九春

    2015-01-01

    新建浦东大道赵家沟大桥主桥为下承式系杆拱桥,采用先梁后拱的施工工艺,其中拱肋采用在桥面结构上搭设塔架施工的竖转提升工艺,纵、横梁及桥面板支撑采用混合支架。临时支架采用φ609钢管桩+贝雷梁+φ48小钢管组成的复合支架形式,承受桥道系结构施工时的荷载、预应力张拉引起的次效应以及竖转提升工艺所传递的荷载,受力较为复杂。采用精细化数值模拟技术对支架与结构在整个施工过程中的受力状态进行模拟,数值模拟结果及实践监测数据表明结构安全,支架的各部分构件受力满足要求,所设计的支撑柱改善了桥道系结构、贝雷梁以及钢管支架的受力状态。%T he main bridge of Zhaojiagou Bridge on the new ly built Pudong Avenue is a bow string tied arch bridge constructed by the process of girder first and arch later ,among w hich the arch ribs adopt the vertical rotating and lifting technique with the assistance of lifting frames erec‐ted on the bridge deck ,the stringers and cross beams and bridge deck are supported on composite scaffolds .The temporary support system is a combined system formed of theφ609 steel piles ,bai‐ley trusses and theφ48 small diameter steel pipes ,w hich bears the loads of the bridge deck system during the construction process , secondary effect caused by prestress tensioning and the loads transmitted by the vertical rotating and lifting technique ,therefore ,the load bearing condition is complex .The refined numerical simulation technique was used to simulate the load bearing condi‐tion of the support system and structure during the w hole construction process .T he results of the numerical simulation and the practical monitoring data demonstrate that the structure is safe ,and the load bearing capacity of each component of the support system meets the requirements and the designed supporting posts improve the load bearing

  1. Optimal Design of a Push-Pull-Forward Half-Bridge (PPFHB) Bidirectional DC–DC Converter With Variable Input Voltage

    DEFF Research Database (Denmark)

    Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.

    2012-01-01

    This paper presents a low-cost bidirectional isolated dc–dc converte, derived from dual-active-bridge converter for the power sources with variable output voltage like supercapacitors. The proposed converter consists of push-pull-forward circuit half-bridge circuit (PPFHB) and a high-frequency tr...... by digital signal processor for comparison purpose. Detailed test results verify the theoretical analysis and demonstrate the validity of optimization design method....... efficiency, optimal design methods and criteria are investigated, including coupled inductors design, bidirectional power flow analysis, harmonics analysis, and ZVS range extension. Based on all the optimal parameters, higher efficiency can be achieved. Finally, prototypes are built in laboratory controlled...

  2. 道路桥梁设计中的隐患及解决措施分析%Hazard analysis and solutions design of roads and bridges

    Institute of Scientific and Technical Information of China (English)

    刘一兵

    2015-01-01

    道路桥梁是重要的基础设施,是公路交通的核心组成部分,道路桥梁建设顺利,经济和社会发展就有了保障,反之,如果道路桥梁出现设计和施工的隐患和问题,那么非但会影响公路交通的畅通,而且还会形成对经济和社会的巨大风险与威胁。本研究以道路桥梁建设中的设计工作为中心,展开了道路桥梁设计隐患的相关研究,在分析道路桥梁设计中存在问题和隐患的基础上,提供了解决道路桥梁设计隐患和问题的措施。%The roads and bridges are important infrastructure is a core component of road traffic, road construction bridge smoothly, economic and social development have security, on the contrary, if there is risk, and the design and construction of roads and bridges, then not only will affect the highway traffic flow, but also the formation of a huge economic and social risks and threats. In this study, road construction, bridge design work for the center, launched a road bridge design risks related research, basic problems and pitfalls in the analysis on the design of roads and bridges, roads and bridges designed to provide a solution measures risks and problems.

  3. Problem Analysis of Pedestrian Bridge Design%人行天桥设计若干问题分析

    Institute of Scientific and Technical Information of China (English)

    晏江; 童琪; 王艳华

    2012-01-01

    文章从使用功能、绿化、照明干扰、舒适度及汽车激振效应等方面入手,对人行天桥景观设计和动力性能设计中存在的主要问题进行了分析,并提出了相应的解决对策与建议。%From the usage function, greening, lighting interference, comfortability and automotive exciting effect etc, the article analyzed the major problems existing in the pedestrian bridge landscape design and dynamic performance design,and proposed some corresponding countermeasures and suggestions.

  4. 新型高速铁路专用桥梁检测车的设计方案%Design scheme of bridge-inspection vehicle applies for new high-speed railway bridge

    Institute of Scientific and Technical Information of China (English)

    张效奎; 刘伟; 韩国梁; 李娟娟

    2012-01-01

    In order to solve the problems of new high-speed railway bridge cancel human pavement,the skylight time limit and other characteristics that traditional bridge test equipment maintenance can't reach the detection requirements,a mechanical design plan of new high-speed railway bridge-detection vehicle was investigated. This bridge-detection vehicle uses the structure of fixed gate-type girder,its guiding girder and drive girder walk alternately. This vehicle can detect the onderkant of the bridge and bridge piers with image acquisition technology and can pass the bridge pier automatically without affect the normal train traffic. And its 3D modeling and simulation animation was completed by Solidworks.the virtual prototype was tested. The experimental results show that this design scheme is feasible. This plan will provide reference to more testing and maintenance of railway bridge equipment research and development.%为了解决新型高速铁路桥梁取消人行便道、受“天窗”时间限制等传统桥梁检测维护设备不能达到检测要求的问题,提出了一种新型高速铁路专用桥梁检测车的机械设计方案.该检测车设计采用门式梁固联、导向梁和驱动梁交替行走结构形式;利用图像采集技术实施对高铁桥梁下表面及桥墩的检测;可在不影响列车正常通行的情况下,实现自动过墩.最后,用Solidworks完成了三维建模及动画仿真,并进行了虚拟样机试验.研究结果表明,该设计方案是可行的,为更多高速铁路桥梁检测维护设备研发提供了借鉴和参考.

  5. 多孔斜交下穿铁路顶进框架设计%Design of the Jacking Frame Crossing Railway under Porous Skew Bridge

    Institute of Scientific and Technical Information of China (English)

    郭齐棣

    2013-01-01

      本文以龙岩城区至高新园区城际快速通道下穿铁路框架桥设计为例,探讨多孔斜交下穿铁路顶进框架桥在轨道加固、滑板后背、顶进等方面采取的特殊施工工艺和安全措施。%This paper taking the design of frame bridge cros-sing railway under Longyan city to high-tech park intercity ra-pid channel as an example, discusses the special construction technology and safety measures on aspects like the bridge rein-forcement, skateboarding back, jacking of jacking frame bridg-e crossing railway under porous skew.

  6. Basic research in support of innovative fuels design for the Generation IV systems (F-BRIDGE project)

    International Nuclear Information System (INIS)

    F-BRIDGE (Basic Research in support of Innovative Fuels Design for the GEN IV systems) is a 4-year project which started in 2008. It seeks to bridge the gap between basic research and technological applications for generation IV nuclear reactor systems. One of the challenges for the next generation of reactors is to significantly increase the efficiency in designing innovative fuels. The object of the F-BRIDGE project is to complement the empirical approach by a physically-based description of fuel and cladding materials to enable a rationalization of the design process and a better selection of promising fuel systems. Advanced modelling and separate effects experiments are carried out in order to obtain more exact physical descriptions of ceramic fuels and cladding, at relevant scales from the atomic to the macroscopic scale. Research is also focused on assessing and improving 'sphere-pac' fuel, a composite-ceramics concept which has shown promise. The project activities can be broken down into four main areas: (i) Basic research investigations using a multi-scale approach in both experimentation and modelling to enable the generation of missing basic data, the identification of relevant mechanisms and the development of appropriate models; (ii) Transfer between technological issues and basic research by bringing together within the same project materials scientists, engineers and end-users; (iii) Assessment of the drawbacks and benefits of the sphere-pac fuel application to various Generation IV systems; (iv) Education and training to promote research in the field of fuel materials, to ensure the exchange of results and ideas among the participants and to link the project with other related European or international initiatives. The project relies on the complementary expertise of 19 partners: nuclear and non nuclear research organisations, universities, a nuclear engineering company, as well as technology and project management consultancy small and medium

  7. Trialogues: a framework for bridging the gap between people research and design

    NARCIS (Netherlands)

    Postma, C.E.; Lauche, K.; Stappers, P.J.

    2009-01-01

    In design research literature, several tools and techniques have been developed that support design teams in establishing creative understandings of people and their contexts of product use, e.g. [1] [2] [3]. Many of these approaches suggest that designers simply adopt the role of people researcher.

  8. Formal Functional Test Designs: Bridging the Gap Between Test Requirements and Test Specifications

    Science.gov (United States)

    Hops, Jonathan

    1993-01-01

    This presentation describes the testing life cycle, the purpose of the test design phase, and test design methods and gives an example application. Also included is a description of Test Representation Language (TRL), a summary of the language, and an example of an application of TRL. A sample test requirement and sample test design are included.

  9. 谈一座景观人行天桥的设计%Discussion on the design of a landscape-style pedestrian bridge

    Institute of Scientific and Technical Information of China (English)

    王佳

    2015-01-01

    Combining with a practical project,this paper introduces the design for the pedestrian bridge mainly by descrbing the landscape design in such aspects as the structure form,rail,bridge deck pavement,the stress,stiffness and natural vibration frequency of the bridge is analyzed by using finite element software,put forward the construction scheme of the pedestrian bridge. It can be consulted by similar bridge design.%以实际工程为例,简要介绍了天桥结合景观在结构形式、栏杆、桥面铺装等方面的设计手法,并采用有限元软件,对天桥应力、刚度及自振频率进行了分析,据此提出了桥梁施工方案,可为类似工程设计提供参考。

  10. 基于可靠度的组合桥梁设计及维护策略%Reliability-Based Design and Maintenance Strategy for Composite Bridges

    Institute of Scientific and Technical Information of China (English)

    张慕圣; 陈锐斌

    2012-01-01

    Currently,the design practice of highway bridges around the world are moving towards limit states design,a reliability-based design procedure.Canadian Highway Bridge Design Code (CHBDC) is the first design code entirely developed based on limit states design philosophy,including foundations and FRP components.However,reliability of a structure decreases in service due to environmental attacks and material deterioration such as fatigue,corrosion and many other reasons.Therefore,the structure should be inspected periodically,and the reliability of the structure should be evaluated according to its age and field data.If its reliability is reduced to a certain level,a repair should be scheduled as well as some preventive maintenance measures should be implemented to prevent further deterioration.Recently,many research works have been conducted to investigate reliability-deterioration mechanisms for each type of infrastructure and its components,optimize the inspection and maintenance strategy,predict remaining service life,estimate its life cycle cost.This paper is focused on the study of reliability-deterioration mechanisms of slab on steel girder bridges due to fatigue and corrosion of steel girders as well as corrosion of reinforcement in the deck slab.Examples will also be given to illustrate the proposed life cycle management strategy for composite slab on steel girder bridges.

  11. Common-mode noise analysis, modeling and filter design for a phase-shifted full-bridge forward converter

    DEFF Research Database (Denmark)

    Makda, Ishtiyaq Ahmed; Nymand, Morten

    2015-01-01

    This paper presents the common-mode noise analysis and modeling of a phase-shifted full-bridge forward converter. The common-mode noise source due to a transformer inter-winding capacitance is considered for the case of study. The generated common-mode noise voltage-source in a converter...... is analytically determined, which then leads to a common-mode noise modeling of a phase-shifted converter. Using a proposed model, common-mode noise-current harmonics are calculated and a fully analytical filter design procedure is presented to comply with the CISPR-11 standard. Finally, a prototype phase......-shifted forward converter is built to verify the theoretical analysis. This study shows that the primary-to-secondary transformer winding capacitance creates a very significant amount of common-mode noise current in a phase-shifted forward converter....

  12. Design and testing of a low-power wireless sensor network for structural health monitoring of bridges

    Science.gov (United States)

    Harms, T.; Banks, B.; Sedigh Sarvestani, S.; Bastianini, F.

    2009-03-01

    This paper describes the design and testing of a wireless sensor network based on the SmartBrick, a low-power SHM device developed by the authors. The SmartBrick serves as the base station for the network, which utilizes additional sensor nodes to periodically evaluate the condition of the structure. Each node measures vibration, tilt, humidity, and strain, and is designed for easy interfacing of virtually any other analog or digital sensor. The sensor nodes use Zigbee to transmit their data to the base station, which in turn uses the GSM cellular phone network to provide long-range communication and support for remote control. The system has been designed from the outset to minimize power consumption, and is projected to operate autonomously for up to four years without any on-site maintenance, due largely to the minimal power consumption and rugged design. Remote calibration over the GSM network further increases the autonomy of the system. Most importantly, it can perform all requisite actions with no cables for power or communication. The focus of this paper is the addition of short-range wireless communication over Zigbee. This allows a network of several devices to be used to monitor larger structures, such as multi-span bridges. Results of laboratory testing are included and discussed in detail, demonstrating the unique capabilities of the proposed SHM system.

  13. Enhancing the thermostability of a cold-active lipase from Penicillium cyclopium by in silico design of a disulfide bridge.

    Science.gov (United States)

    Tan, Zhongbiao; Li, Jianfang; Wu, Minchen; Wang, Junqing

    2014-08-01

    Cysteine mutants of a cold-active lipase (PcLipI) from Penicillium cyclopium were designed by the software Disulfide by Design Ver. 1.20 in an effort to improve enzyme thermostability by addition of a disulfide bridge. Those mutants predicted by molecular dynamics simulation to have better thermostability than the wild type were first expressed in Escherichia coli BL21(DE3) and then, for further investigation, in Pichia pastoris GS115. By replacing Val248 and Thr251 with cysteines to create a disulfide bridge, the recombinant lipases reE-PcLipV248C-T251C (expressed in E. coli) and reP-PcLipV248C-T251C (expressed in P. pastoris) were obtained. Both had enhanced thermostability with half-lives at 35 °C about 4.5- and 12.8-fold longer than that of the parent PcLipI expressed in E. coli and P. pastoris, respectively. The temperature optima of reE-PcLipV248C-T251C and reP-PcLipV248C-T251C were 35 and 30 °C, which were each 5 °C higher than those of the parent PcLipI expressed in E. coli and P. pastoris. The K ms of reE-PcLipV248C-T251C and reP-PcLipV248C-T251C toward tributyrin were 53.2 and 39.5 mM, while their V maxs were 1,460 and 3,800 U/mg, respectively. PcLipV248C-T251C had better thermostability and catalytic efficiency than the other mutants and the parent PcLipI. PMID:24867629

  14. 郑州市解放路跨线桥主桥设计与施工%Design and Construction of Main Bridge of Jiefang Road Overpass Bridge in Zhengzhou City

    Institute of Scientific and Technical Information of China (English)

    申国朝

    2012-01-01

    The main bridge of the Jiefang Road Overpass Bridge in Zhengzhou City is a cable-stayed bridge with twin pylons, single cable plane and with span arrangement (106 + 248 + 106) m and the bridge employs the structural system of rigid fixity of its pylons and main girder. The main girder of the bridge is of the prestressed concrete triple-cell single box of quasi-triangle section and has a 62 m long variable width portion at the side span on the west side. On both sides of a pylon, 15 pairs of stay cables made up of the low relaxation and high-strength galvanized parallel steel wires are arranged. The pylons are the concrete solid single-column ones of H-shape sections and the main piers are the vase shape hollow reinforced concrete structures supported on the frictional group bored pile foundations. The software Bridge Doctor V3. 03, MIDAS Civil and ANSYS were used to respectively build the plane finite element model for the bridge and the plane link and spatial plate-shell finite element models for the variable width portion. With these models, the global static force of the bridge and the force conditions of the portion were analyzed. In addition, a 1: 4 model for the variable width portion was also designed and made to carry out the model test. The results of the finite element analysis and model test showed that the force conditions of various parts of the bridge could meet the requirements in the codes. The part of the bridge spanning the passenger dedicated railway line on the east side was constructed by the rotation erection while the part of the bridge spanning the freight railway line on the west side was constructed by the covered form traveler.%郑州市解放路跨线桥主桥为双塔单索面斜拉桥,跨径布置为(106+248+106)m,采用塔、梁固结体系.该桥主梁为预应力混凝土单箱三室准三角形截面,西侧边跨设62 m长的变宽段.每个桥塔两侧布置15对斜拉索,斜拉索采用低松弛镀锌高强平行钢丝.桥塔采

  15. Design of Main Bridge of Xi′nan Bridge in Guigang City,Guangxi%广西贵港西南大桥主桥设计

    Institute of Scientific and Technical Information of China (English)

    李翠霞; 张巨生

    2015-01-01

    广西贵港市西南大桥主桥为(46+88+280+88+46) m双塔双索面预应力混凝土边主梁斜拉桥。主梁采用等高度带悬臂的矩形混凝土边主梁与“工”字形钢横梁相结合的形式,整幅桥面宽36.5m,设双向2.0%横坡。桥塔采用“鱼”状流线弧形框架钢筋混凝土结构,塔柱高102.5 m,采用外侧为“D”形圆弧段的箱形截面。桥塔设上、下横梁,均采用预应力混凝土单箱单室结构。全桥共设136根斜拉索,斜拉索采用φs 15.2 m m镀锌钢绞线索,空间双索面扇形布置。桥塔墩采用分离式基础,上、下游分离式基础中心距34.7 m ,其下各设9根φ2.5 m钻孔桩。承台为正方形钢筋混凝土结构。4号墩顶面设一圆端形塔座。%The main bridge of the Xi′nan Bridge in Guigang City ,Guangxi is a prestressed concrete edge main girders cable‐stayed bridge with double pylons ,double cable planes and with span arrangement (46+88+280+88+46) m .T he main girders of the bridge are of the structural type combining the rectangular concrete edge main girders having constant depth and cantilevers with the I‐shape steel cross beams .The width of the whole bridge deck is 36 .5 m and the deck is provided with dual 2 .0% transverse slopes .A pylon of the bridge is the“fish”‐shape streamlined arc frame reinforced concrete structure that is 102 .5 m in height and the outer side of the pylon is of the“D”‐shape round arc box section .The upper and lower cross beams of the pylon are all the prestressed concrete single‐cell single‐box structures .There are totally 136 stay cables arranged for the whole bridge .The stay cables are the φs 15 .2 mm galvanized steel wire strand cables and are arranged in fan shape and spatial double cable planes .The pylon pier is supported on the sep‐arated foundations .T he center‐to‐center distance of the foundations on the upstream and dow n‐stream sides is 34 .7

  16. Design and construction of Sutong Bridge deep-water main-pylon foundations

    Institute of Scientific and Technical Information of China (English)

    Ren Huixing; Ouyang Xiaoyong; He Maosheng; Nie Qinlong; Wang Xiali

    2009-01-01

    This paper, from three aspects including construction conditions, foundation design and construction, introduces some considerations in the designing of main-pylon foundations and some practical measures to deal with certain unfavorable construction conditions, such as deep water, tidal effect, soft stratum and heavy traffic, during the construction of main-pylon foundations.

  17. Design of an aluminium bicycle path integrated in a steel bridge

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Burggraaf, H.G.

    2007-01-01

    This paper describes the design of the aluminium structure of a bicycle path which is mounted on an existing steel brige. The benefits of aluminium, being low self weight, freedom in design obtained by extrusion and good corrosion resistance were maximal utilized. One of the main drawbacks of alumin

  18. Uptake and Use of Technology: Bridging Design for Teaching and Learning

    Science.gov (United States)

    Hauge, Trond Eiliv

    2014-01-01

    This paper demonstrates the need for taking a design perspective on teaching and learning in the study of the uptake and use of information and communication technologies (ICT) in education. It argues for the identification and scrutiny of designs for teaching and learning at the institutional level to overcome the contradictions that often arise…

  19. Bridging the Gap between Designers and Consumers: The Role of Effective and Accurate Personas

    Science.gov (United States)

    Miaskiewicz, Tomasz

    2010-01-01

    Firms now routinely collect information about the needs of their customers, but this information is not sufficiently considered during product design decisions. This research examines the relationship between designers and consumers to build an understanding of how the consumer should be represented to increase the consumer focus during the…

  20. Bridging the Gap between Eco-Design and the Human Thinking System

    Directory of Open Access Journals (Sweden)

    Mona Komeijani

    2016-03-01

    Full Text Available Technological progress has enabled widespread adoption and use of consumer electronics, changing how global society lives and works. This progress has come with immense environmental cost, including extraction of scarce materials, consumption of fossil fuels, and growing e-waste challenges. Eco-design has emerged as a promising approach to reduce the environmental footprint of electronics by integrating sustainability-oriented decisions early in the product realization process. However, most approaches focus on the product itself, not on the consumer who ultimately decides how to purchase, use, maintain, and dispose of the device. This article presents a new framework to guide designers in developing products with features that encourage consumers to use them in an environmentally sustainable manner. The Sustainable Behavior Design (SBD framework links common design concepts (ergonomic, emotional, preventative, and interaction design with core aspects of the human thinking system to create features to make users aware of their behavior and decisions (reflective thinking or result in sustainable behaviors even when users are unaware (automatic thinking. The SBD framework is demonstrated using a case study on a smartphone, a high demand product. The reimagined smartphone design integrates solutions addressing both automatic and reflective thinking systems, potentially reducing life cycle impacts by almost 30%.

  1. Comparison of infrastructure designs for quay wall and small bridges in concrete, steel, wood and composites with regard to the co2-emission and the life cycle analysis

    NARCIS (Netherlands)

    Van Heel, D.D.; Maas, T.; De Gijt, J.G.; Said, M.

    2011-01-01

    This paper describes quay wall and bridge designs in different materials, which are compared with regard the the CO2-emission and the Life Cycle Analysis (LCA). For this study the requirements and boundary conditions from the Euromax Terminal quay wall, in the Port of Rotterdam, have been used. The

  2. Design of Concrete Self-Anchored Suspension Bridge of Wusong Bridge in Jilin City%吉林市雾凇大桥混凝土自锚式悬索桥设计

    Institute of Scientific and Technical Information of China (English)

    张伟; 唐贺强; 宁伯伟

    2011-01-01

    The main bridge of the Wusong Bridge in Jilin City is a 5-span continuous concrete self-anchored suspension bridge with span arrangement (35+68+150+68+35) m. A summarized account of the design and calculation of the main bridge is presented herewith. On the bridge, the transverse and vertical bearings and the longitudinal dampers are arranged in between the stiffening girder and towers. The girder is of a concrete 3-cell single box section, the depth of a typical segment of the girder is 2.5 m and towards the anchorage sections at the side spans, the segments of the girder gradually change into a depth of 6.5 m. A tower of the bridge is a concrete portal frame structure that is 54 m in height and the tower columns and the cross beams on the towers are all of rectangular hollow sections. Beneath a tower pier are the pile caps of separation type and each pile cap is supported by 9 nos. of Φ2.0 m bored piles. The main cables are respectively made up of Φ5.1 mm galvanized high strength steel wires and the hanger cables are of Φ7.0 mm low relaxation galvanized high strength parallel steel wires. In the design, the finite element software MIDAS Civil 2006, the nonlinear analysis software BNLAS for suspension bridge and the plane program SCDS are employed to calculate and analyze the bridge. The results of the calculation and analysis indicate that all checking calculation made for the bridge can conform to the relevant requirements in the codes.%吉林市雾凇大桥主桥为(35+68+150+68+35)m五跨连续混凝土自锚式悬索桥,综述该桥主桥设计与计算.该桥塔梁间设置横、竖向支座和纵向阻尼器;加劲梁采用单箱三室混凝土截面,标准段梁高2.5 m,在边跨锚固段渐变至6.5 m;桥塔采用门形框架混凝土结构,高54 m,塔身及横梁均采用矩形空心截面;桥塔墩下部采用分离式承台,单个承台布置9根φ2.0 m钻孔灌注桩;主缆采用φ5.1 mm镀锌高强钢丝,吊索采用φ7.0 mm低松弛镀锌高强

  3. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents

    OpenAIRE

    Yong-Tao Duan; Ruo-Jun Man; Dan-Jie Tang; Yong-Fang Yao; Xiang-Xiang Tao; Chen Yu; Xin-Yi Liang; Jigar A. Makawana; Mei-Juan Zou; Zhong-Chang Wang; Hai-Liang Zhu

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide–bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, 1H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal hu...

  4. Intersection how enterprise design bridges the gap between business, technology, and people

    CERN Document Server

    Guenther, Milan

    2012-01-01

    Many organizations struggle with the dynamics and the complexity of today''s social ecosystems that connect everyone and everything, everywhere and all the time. Facing challenges at the intersection of business models, technical developments, and human needs, modern enterprises must overcome the siloed thinking and isolated efforts of the past, and instead address their relationships to people holistically. In Intersection, Milan Guenther introduces a Strategic Design approach that aligns the overarching efforts of Branding, Enterprise Architecture, and Experience Design, and sets them on a

  5. Structure-Based Design of a Novel SMYD3 Inhibitor that Bridges the SAM-and MEKK2-Binding Pockets.

    Science.gov (United States)

    Van Aller, Glenn S; Graves, Alan P; Elkins, Patricia A; Bonnette, William G; McDevitt, Patrick J; Zappacosta, Francesca; Annan, Roland S; Dean, Tony W; Su, Dai-Shi; Carpenter, Christopher L; Mohammad, Helai P; Kruger, Ryan G

    2016-05-01

    SMYD3 is a lysine methyltransferase overexpressed in colorectal, breast, prostate, and hepatocellular tumors, and has been implicated as an oncogene in human malignancies. Methylation of MEKK2 by SMYD3 is important for regulation of the MEK/ERK pathway, suggesting the possibility of selectively targeting SMYD3 in RAS-driven cancers. Structural and kinetic characterization of SMYD3 was undertaken leading to a co-crystal structure of SMYD3 with a MEKK2-peptide substrate bound, and the observation that SMYD3 follows a partially processive mechanism. These insights allowed for the design of GSK2807, a potent and selective, SAM-competitive inhibitor of SMYD3 (Ki = 14 nM). A high-resolution crystal structure reveals that GSK2807 bridges the gap between the SAM-binding pocket and the substrate lysine tunnel of SMYD3. Taken together, our data demonstrate that small-molecule inhibitors of SMYD3 can be designed to prevent methylation of MEKK2 and these could have potential use as anticancer therapeutics.

  6. A contribution to the hydraulic design of bridges in coastal zones; Una contribucion al diseno hidraulico de puentes en zonas costeras

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Bribiesca, J.L.; Gracia Sanchez, J. [Instituto de Ingenieria, UNAM, Mexico, D.F. (Mexico)

    2004-06-01

    It is proposed a criterion to determine, from the hydraulic point of view, the width and the height of bridges of coastal zones. The criterion uses information of failed and not failed bridges (both in the same current). The criterion allows the design of new bridges and the revision of the existing ones others existent ones. Numerical examples are included. [Spanish] Se presenta un criterio para determinar el ancho y la altura de puentes sobre rios de zonas costeras desde el punto de vista hidraulico. El criterio empleo informacion de puentes fallados y no fallados (sobre una misma corriente); asimismo, permitio tanto el diseno de puentes nuevos, como la revision de otros existentes. Se incluyen ejemplos numericos.

  7. Cybersecurity Protection: Design Science Research toward an Intercloud Transparent Bridge Architecture (ICTOBRA)

    Science.gov (United States)

    Wilson, Joe M.

    2013-01-01

    This dissertation uses design science research and engineering to develop a cloud-based simulator for modeling next-generation cybersecurity protection frameworks in the United States. The claim is made that an agile and neutral framework extending throughout the cyber-threat plane is needed for critical infrastructure protection (CIP). This…

  8. Read To Succeed: MECCA Summer Learning Camp. Manual To Design and Deliver a Summer Bridges Program.

    Science.gov (United States)

    Illinois State Board of Education, Springfield.

    This manual presents information on designing and delivering a summer learning program whose goal is to provide an opportunity for students to experience academic success and positive self-esteem through reading fluency and comprehension. Sections of the manual address background and policies (on student and teacher selection, student promotion,…

  9. Building Bridges to Connect the Disconnects: An Analysis of Business Program Design Processes

    Science.gov (United States)

    Fleming, Debra L.

    2008-01-01

    The purpose of this study is to analyze current trends of design processes and redesign efforts for business programs. A review of the literature suggests business schools are not preparing graduates of their programs with the necessary knowledge, skills and dispositions as deemed appropriate to succeed in the world of work. Some research studies…

  10. Bridging the gap: The design of bank loan contracts and distance

    NARCIS (Netherlands)

    Hollander, Stephan; Verriest, A.J.M.

    2016-01-01

    How do the distance constraints faced by lenders in acquiring borrower information affect the design of bank loan contracts? Theoretical studies posit that greater information asymmetry leads to the allocation of stronger ex ante decision rights to the lender (the uninformed party). Consistent with

  11. 平行弦钢桁架过街人行天桥设计%The Design of a Parallel Chord Steel Truss Pedestrian Bridge

    Institute of Scientific and Technical Information of China (English)

    董震

    2016-01-01

    分析北京某平行弦桁架人行过街天桥设计,该天桥主体结构由上部两榀钢桁架和下部混凝土柱组成,总长52.5m,单跨最大跨径30m。设计考虑竖向地震、温度效应等荷载作用,并计算结构竖向第一振动频率,避免人群行走时桥身产生共振。设计方法和结构选型可供技术人员作同类设计参考。%The paper describes the design of a parallel chord steel truss pedestrian bridge in Beijing. The main structure of the bridge is composed of above two steel trusses and concrete columns bottom. The most span of the bridge is 30m, and the whole length is 50m. The structure calculation includes of the vertical earthquake, temperature effect and the first natural frequency of vertical vibration for avoiding the resonance of the bridge caused by human walking. The design method and selection of the structure provide reference for similar design.

  12. Modelling and design of planar Hall effect bridge sensors for low-frequency applications

    DEFF Research Database (Denmark)

    Persson, Åsa; Bejhed, R.S.; Østerberg, Frederik Westergaard;

    2013-01-01

    .g., disregarding shape anisotropy effects, and also incorporates some approximations. To validate the results, modelled data was compared to measurements on actual PHEBs and was found to predict the measured values within 13% for the investigated geometries. Subsequently, the model was used to establish a design...... and moderate noise figure. In this work, the applicability of such PHEB sensors to different areas is investigated. An analytical model is constructed to estimate the performance of an arbitrary PHEB sensor geometry in terms of, e.g., sensitivity and detectivity. The model is valid for an ideal case, e...... process for optimizing a PHEB to a particular set of requirements on the bandwidth, detectivity, compliance voltage and amplified signal-to-noise ratio. By applying this design process, the size, sensitivity, resistance, bias current and power consumption of the PHEB can be estimated. The model indicates...

  13. Design of Bridge Expansion Joints with Perforated Dowels Under Impact Loading

    Institute of Scientific and Technical Information of China (English)

    YODA Teruhiko; AYASHI Mamiko

    2008-01-01

    The expansion joints are expected to have movement capacity.bearing capacity for stahc and dynamic loading,water-tightness,low noise emission and traffic safety.In particular.the tailure due to impact loading is the main reason for the observed damaaes.The problem of dynamic behavior of the expansion joints is so complex that we shall focus our attention on the impact factor for vehicle load that is governed by traffic impact.In order to overcome this difficulty. the cantilever-toothed aluminum joint(finger joint)is one of the promising joints under impact load-ing.In this study,from the viewpoint of design methodology.numerical studies for impact be-havior were conducted for aluminum alloy expansion joints with perforated dowels.The design im-pacf factor for the expansion joints with the perforated dowels against traffic impact loading was examined by using numerical simulations.

  14. Bridging sustainability and intensified flow processing within process design for sustainable future factories

    OpenAIRE

    Kralisch, Dana; Ott, Denise; Kressirer, Sabine; Staffel, Christin; Sell, Ina; Krtschil, Ulrich; Loeb, Patrick

    2013-01-01

    A holistic, life cycle based evaluation approach was followed within the European collaborative project CoPIRIDE, in order to provide multi-criteria decision support for environmentally benign and cost efficient process design strategies in front of a scale-up of newly developed concepts. The approach is presented by means of three case studies, dealing on the one hand with different catalyst plate reuse options, and on the other hand with two process concepts for intensified processing of na...

  15. Simplified serviceability design of jointless structures. Experimental verification and application to typical bridge and building structures

    OpenAIRE

    Groli, Giancarlo; Pérez Caldentey, Alejandro; Giraldo Soto, Alejandro; Marchetto, Francesco; Ezeberry Parrotta, Javier Ignacio

    2014-01-01

    In this article an experimental campaign aimed at validating a previously published simplified serviceability design method of the columns of long jointless structures is presented. The proposed method is also extended to include tension stiffening effects which proved to be significant in structures with small amount of reinforcement subjected to small axial loading. This extension allows significant improvement of predictions for this type of element. The campaign involved columns with diff...

  16. Activity-Based Design as a Way to Bridge Artifacts, Professions, and Theories

    DEFF Research Database (Denmark)

    Brynskov, Martin

    2007-01-01

    This paper will focus on the challenges in designing pervasive computing technology for children’s play, taking into account current trends in popular culture. In search of theoretical support for this work I have been exploring an activity-based approach called ‘habitats’ to describe the conditi......This paper will focus on the challenges in designing pervasive computing technology for children’s play, taking into account current trends in popular culture. In search of theoretical support for this work I have been exploring an activity-based approach called ‘habitats’ to describe...... the conditions around various design projects, and it seems to have some value. I will present my experiences from a playful pervasive gaming system for children and the problems I faced trying to find a solid theoretical paradigm. The paper argues that habitats with its three perspectives – physical......, informational, and pragmatic – together with the ability to describe their relations are a useful platform for practitioners and theorists who are forced to span a heterogeneous mash-up of technologies, theories, and professions....

  17. Design of FPGA- Based SPWM Single Phase Full-Bridge Inverter

    Directory of Open Access Journals (Sweden)

    Afarulrazi Abu Bakar

    2009-12-01

    Full Text Available Nowadays power inverters serve as an important emergency power supply system in events of main power supply failure. The AC output voltage of a power electronic inverter is usually non-sinusoidal and hence has a high harmonic content. Sinusoidal Pulse Width Modulation (SPWM scheme is normally used to convert the DC power supply into AC power supply by comparing the reference voltage waveform with the triangular waveform known as carrier. SPWM provides a way to reduce the total harmonic distortion of load current. The objective of this paper is to demonstrate a SPWM switching scheme by using Altera DE2-70 board. In this SPWM technique, a sinusoidal reference voltage waveform is compared with the triangular carrier voltage to generate the on and off switching states. This switching scheme will trigger the gate of the power switch. In this paper, the SPWM switching strategies implemented using Altera DE2-70 (Cyclone II EP2C35F672C6 with 16 bit serial configuration devices. The switching between reference and carrier waveforms of SPWM is obtained by using Matlab software. Simulation on the design waveform is conducted using Quartus II software tools provided by Altera. The output frequency of SPWM is 50 Hz and the design is limited to two values of modulation indices which are 0.5 and 0.75.

  18. Molecular design of organic dyes based on vinylene hexylthiophene bridge for dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Three donor-(π-spacer)-acceptor(D-π-A) organic dyes,containing different groups(triphenylamine,di(p-tolyl)phenylamine,and 9-octylcarbazole moieties) as electron donors,were designed and synthesized.Nanocrystalline TiO2 dye-sensitized solar cells were fabricated by using these dyes.It was found that the variation of electron donors in the D-π-A dyes played an important role in modifying and tuning photophysical properties of organic dyes.Under standard global AM 1.5 solar condition,the DSSC based on the dye D2 showed the best photovoltaic performance:a short-circuit photocurrent density(Jsc) of 13.93 mA/cm2,an open-circuit photovoltage(Voc) of 0.71 V,and a fill factor(FF) of 0.679,corresponding to solar-to-electric power conversion efficiency(η) of 6.72%.

  19. Molecular design of organic dyes based on vinylene hexylthiophene bridge for dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    LIU DaXi; ZHAO Bin; SHEN Ping; HUANG Hui; LIU LiMing; TAN SongTing

    2009-01-01

    Three donor-(TT-spacer)-acceptor (D-tt-A) organic dyes,containing different groups (triphenylamine,di(p-tolyl)phenylamine,and 9-octylcarbazole moieties) as electron donors,were designed and synthesized. Nanocrystalline TiO2 dye-sensitized solar cells were fabricated by using these dyes. It was found that the variation of electron donors in the D-tt-A dyes played an important role in modifying and tuning photophysical properties of organic dyes. Under standard global AM 1.5 solar condition,the DSSC based on the dye D2 showed the best photovoltaic performance: a short-circuit photocurrent density (Jsc) of 13.93 mA/cm2,an open-circuit photovoltage (Voc) of 0.71 V,and a fill factor (FF) of 0.679,corresponding to solar-to-electric power conversion efficiency (77) of 6.72%.

  20. Design of Gutianxi Bridge on Hefei-Fuzhou Railway%合福铁路古田溪特大桥设计

    Institute of Scientific and Technical Information of China (English)

    李浩勇

    2012-01-01

    古田溪特大桥是新建合福铁路重点控制桥梁工程之一,该桥集高墩大跨、深水基础于一身,兼具山区铁路与高速铁路双重特点,设计施工难度大。研究其桥式方案选择及设计施工要点,通过分析无缝线路特性,合理确定主桥桥式方案;结合施工组织,总结了主跨梁部结构、主桥桥墩及主墩基础的设计施工要点。车桥耦合动力仿真分析结论表明,当车速不超过该桥设计车速350 km/h时,安全性指标均在限值以内。%Gutianxi Bridge is one of the controlling bridges for the newly-built Hefei-Fuzhou Railway.It’s characterized as high pier,long span,and deep under-water foundation,with a total length of 588.89 m,highest pier of 49.5 m and under water foundation of 42.4 m.This bridge serves as both mountain railway as well as high speed railway,which has presented great challenges in both design and construction.Through research & study on the selection of the bridge type and the critical points of design & construction,experiences have been accumulated in the design of deep water foundation for high speed railway in mountainous areas.The bridge type of main span has been reasonably determined via analysis on characteristics of seamless rails.The critical points of design & construction for the beam structure,the pier & the foundation of the main span are summarized,in combination with the organization of construction.The dynamic simulation analysis on the interaction between the bridge and the vehicle demonstrates that when the operation speed is not higher than the design speed of 350 km/h,the safety indexes are within limits and the comfort indexes are above the "sound" level,which further proves that the design safety and comfort index are suitable.

  1. Ontology Design Patterns: Bridging the Gap Between Local Semantic Use Cases and Large-Scale, Long-Term Data Integration

    Science.gov (United States)

    Shepherd, Adam; Arko, Robert; Krisnadhi, Adila; Hitzler, Pascal; Janowicz, Krzysztof; Chandler, Cyndy; Narock, Tom; Cheatham, Michelle; Schildhauer, Mark; Jones, Matt; Raymond, Lisa; Mickle, Audrey; Finin, Tim; Fils, Doug; Carbotte, Suzanne; Lehnert, Kerstin

    2015-04-01

    Integrating datasets for new use cases is one of the common drivers for adopting semantic web technologies. Even though linked data principles enables this type of activity over time, the task of reconciling new ontological commitments for newer use cases can be daunting. This situation was faced by the Biological and Chemical Oceanography Data Management Office (BCO-DMO) as it sought to integrate its existing linked data with other data repositories to address newer scientific use cases as a partner in the GeoLink Project. To achieve a successful integration with other GeoLink partners, BCO-DMO's metadata would need to be described using the new ontologies developed by the GeoLink partners - a situation that could impact semantic inferencing, pre-existing software and external users of BCO-DMO's linked data. This presentation describes the process of how GeoLink is bridging the gap between local, pre-existing ontologies to achieve scientific metadata integration for all its partners through the use of ontology design patterns. GeoLink, an NSF EarthCube Building Block, brings together experts from the geosciences, computer science, and library science in an effort to improve discovery and reuse of data and knowledge. Its participating repositories include content from field expeditions, laboratory analyses, journal publications, conference presentations, theses/reports, and funding awards that span scientific studies from marine geology to marine ecology and biogeochemistry to paleoclimatology. GeoLink's outcomes include a set of reusable ontology design patterns (ODPs) that describe core geoscience concepts, a network of Linked Data published by participating repositories using those ODPs, and tools to facilitate discovery of related content in multiple repositories.

  2. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  3. Determination of Design Scheme for Chongqing- Fuling Railway Under-passing Wutong Overpass Bridge%渝涪线下穿五童立交方案研究

    Institute of Scientific and Technical Information of China (English)

    丁兆锋

    2011-01-01

    Research purposes: During the construction of the railway terminal, when the new or additional railway under - passes the existing road bridge, the factors that affect the safety of existing bridges should be considered carefully in the design and the safety of the existing bridge becomes an important issue in the railway construction because the construction condition is limited.On considering the technical and economic factors, the design schemes for Chongqing -Fuling Railway under -passing the Wutong Overpass Bridge in Chongqing were compared and the best scheme was selected to reduce the negative factors that affected the safety of the bridge for the purpose of providing the references to the similar works.Research conclusions: In general, when a new or additional railway under - passes the existing road bridge, the scheme should be reasonably selected on consideration of economic, technical, security and other factors.Minimizing the impact of construction of a new or aditional railway on the existing road bridge is crucial to construction of a new or additional railway under - passing the existing road bridge.The pile - board structure was used for construction of Chongqing -Fuling Railway under - passing the Wutong road bridge to transfer the top load to the bed rock by the pile.In this case,the safety of existing bridge and the stability of the existing subgrade can be ensured.This scheme is the best one because of minimizing the impact of railway construction on the existing road bridge.%研究目的:在铁路枢纽建设中,新建或增建铁路下穿既有公路桥时,因其施工条件受限制,设计时需对影响既有桥安全因素做周详考虑,而成为重要的铁路工程问题之一,本文通过技术及经济等因素对渝涪线在重庆枢纽段下穿既有五童立交桥的方案进行比选,以减小不利因素对既有公路桥安全的影响,为设计者提供参考,为类似工程供提供借鉴.研究结论:一般情况下,对于

  4. Environmental life cycle assessment comparison between two bridge types: reinforced concrete bridge and steel composite bridge

    DEFF Research Database (Denmark)

    Du, Guangli; Karoumi, Raid

    2013-01-01

    not been integrated into the decision-making process. This paper presents a systematic LCA method for quantifying the environmental impacts for bridges. The comparison study is performed between a reinforced concrete bridge and a steel bridge as an alternative design, with several key maintenance and EOL......The concept of sustainable construction has attracted an increased attention. Bridge infrastructures and their belonged construction activities consume considerable material and energy, which is responsible for large environmental burdens. However, the environmental assessment of bridges has...

  5. 铂电阻非平衡电桥温度计的设计%Design of the Unbalanced Bridge Thermometer Using Platinum Resistance

    Institute of Scientific and Technical Information of China (English)

    冯叶; 蒋方为; 张宇鹍; 王吉有

    2016-01-01

    利用Matlab和Origin软件,从理论上分析了电压型非平衡电桥铂金属温度计设计中,各种参数对温度线性度的影响。设计了0~100℃范围的温度计,获得电桥的输出电压和测量温度具有很好的线性关系。%The influence of a variety of parameters on the linear of the thermometer in the design of the unbal-anced bridge are theoretically analyzed using Matlab software and Origin software. The thermometer was de-signed to obtain 0~100℃range.It was found that it has a good linear relationship between the output voltage of unbalanced bridge and temperature.

  6. 桥梁结构设计课程改革探讨%Discussion on teaching reform of Bridge Structure Design

    Institute of Scientific and Technical Information of China (English)

    马利耕

    2012-01-01

    借鉴国外高职教育成功的办学经验,重点探讨了《桥梁结构设计》课程改革的目标、思路、方法,提炼了《桥梁结构设计》课程改革的特色,展望了课程改革将取得的成效。%This paper drew the successful teaching experience of foreign higher vocational education, focus discussed the reform goal, train of thought, method of Bridge Structure Design curriculum, refined the reform characteristic of Bridge Structure Design curriculum, prospect the cur riculum reform results.

  7. Analysis of Highway Bridge Design and New Construction Technology%公路桥梁设计及施工新技术分析

    Institute of Scientific and Technical Information of China (English)

    张生霞

    2015-01-01

    本文结合GPS新技术、计算机技术以及混凝土新技术等,并对我国目前公路桥梁设计中使用的新技术进行了分析,提出了一些完善公路桥梁设计以及施工的建议,以供参考。%Combining with the GPS new technology, computer technology and new concrete technology, this paper analyzes the new technology used in the current design of highway bridges in China, and puts forward some sug⁃gestions for improving the design and construction of highway bridges for reference.

  8. Discuss the Safety and Durability in the Design of Bridge%论述路桥设计中的安全性和耐久性

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    The economic development cannot leave behind th-e roads and bridges and other infrastructure, and the roads and bridges projects have gradual y become the basis for China's economic development. The roads and bridges in our country developed rapidly in recent years, but due to design or constru-ction, the road and bridge engineering are still risks in the asp-ects of safety and durability.%  经济的发展离不开道路桥梁等基础设施的建设,道路桥梁工程也逐渐成为影响我国经济发展的基础。我国的道路桥梁在近几年得到了迅速发展,但由于设计或施工的原因,路桥工程在安全性与耐久性等方面还存在着隐患。

  9. A Protocol Bridge Between Bluetooth Low Energy and IEEE 802.15.4 Based LR-WPANs: Concept, Design and Prototype

    OpenAIRE

    Svendsen, Tobias Borén; Trydal, Dag-Are; Brekke, Anders

    2013-01-01

    The interconnection between electronic devices is increasing and wireless technologies are replacing wires at a high pace. Smartphones are today common property and their area of application is growing rapidly. Even so, a smartphone is still no unified device capable of transceiving every possible wireless protocol. Especially are the standards of the industry often not supported by consumer products.This master thesis presents a possible design for a protocol bridge between Bluetooth Low Ene...

  10. Bridge Design on Dabaodang-Zhangqiao Section of the Baotou-Xi'an Railway%包西铁路通道大保当至张桥段桥梁设计

    Institute of Scientific and Technical Information of China (English)

    唐英

    2013-01-01

    包西铁路通道大保当至张桥段桥梁长度近101 km,桥址地形地貌复杂,主要存在沙漠地区、煤窑采空区、盐渍土地区及湿陷性黄土地区等不良地质;结合客货共线铁路设计特点,简要介绍桥涵工程概况、桥梁类型的选择、桥梁设计原则、不良地质对桥梁设计的影响;对新结构桥梁设计和重点桥梁也作了简述.%The total length of the bridges on Dabaodang-Zhangqiao section of the Baotou-Xi'an Railway is nearly 101 kilometers,and geological condition at these bridge sites is so complex that it contains lots of desert area,coal mined-out area,saline soil area,collapsible loess area and other unfavorable geologies.Combined with the characteristics of mixed passenger and freight railway,this article introduces project overview of the bridges and culverts,bridge type selection,bridge design principle and the effect of unfavorable geological condition on bridge design.In regard to the designs of new bridge structure and key bridge,the article also gives introduction briefly.

  11. 基于桥梁设计中混凝土结构的耐久性设计问题分析%Analysis of Durability Design of Concrete Structure in Bridge Design

    Institute of Scientific and Technical Information of China (English)

    董贵生

    2014-01-01

    我国大部分桥梁结构基本上都是以混凝土结构为主导的。在使用的桥梁中发现,对于桥梁后期的加固维护所投入的费用往往占桥梁建设投资费用的40%~50%以上。因此,在桥梁设计中着重提升混凝土结构的耐久性,可以为桥梁建设未来的发展打下良好的基础。%Most bridge structures are basicaly dominated by concrete structure in China. We found that the bridge reinfo- rcement and maintenance for the late input costs often account for 40% ~ 50% of investment cost of bridge construction. Therefore, focus on improving the durability of concrete str- ucture in bridge design, can be a good foundation for the de- velopment of bridge construction in future.

  12. Design of Main Pier Foundations for Guyumen Channel Bridge of Pingtan Strait Rail-cum-Road Bridge%平潭海峡公铁两用大桥鼓屿门航道桥主墩基础设计

    Institute of Scientific and Technical Information of China (English)

    孙英杰; 梅新咏

    2016-01-01

    平潭海峡公铁两用大桥鼓屿门航道桥采用主跨364 m的钢桁混合梁斜拉桥方案,桥址区水深流急、风大涌险、潮大浪高、地质复杂、冲刷严重、航道等级高、有效作业时间短。为适应该桥桥址气象、水文、地质等条件,考虑通航安全、技术可行及工程经济性等要求,确定采用高桩承台方案,并对φ3.0m、φ4.0m、φ4.5m钻孔桩基础方案进行比选,确定选用φ4.5m钻孔桩基础方案,按先平台后吊箱围堰的顺序施工。大直径桩基础中各桩采用单独配筋设计;防撞结构由吊箱围堰、V形防撞梁及联结系组成,采用可拆卸式设计,并在围堰外壁设置消波孔;钻孔桩采用KTY5000型动力头钻机,并配制PESF935型中压空压机循环排渣,利用泥浆护壁、锲齿或球齿滚刀钻头钻具切削岩面成孔;采用内径406 mm的单导管法施工水下C45混凝土。%The Guyumen Channel Bridge of the Pingtan Strait Rail‐cum‐Road Bridge adopts the scheme of a steel truss hybrid girder cable‐stayed bridge with a main span of 364 m .The construc‐tion of the bridge is constrained by the complex geological and hydrological conditions at the bridge site ,including deep water ,strong currents ,heavy winds ,hazardous torrents ,high tides and tur‐bulent waves ,severe scour ,high grade of navigational channel and tight efficient operation time . To suit the meteorological ,hydrological and geological conditions at the bridge site ,by considering the safety and technical feasibility and engineering economy ,it was determined that the elevated pile cap scheme be adopted .The pile foundations formed of bored piles respectively with 3 .0 m , 4 .0 m and 4 .5 m diameters were compared ,and the foundation scheme of 4 .5 m diameter bored piles was finally chosen .The foundation was constructed following the sequence of constructing the platform first and then the suspended box cofferdam .For the

  13. Analysis, Design, Modelling and Control of an Interleaved-Boost Full-Bridge Three-Port Converter for Hybrid Renewable Energy Systems

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Zhang, Zhe; Knott, Arnold;

    2016-01-01

    This paper presents the design, modelling and control of a three-port (TPC) isolated dc-dc converter based on interleaved-boost-full-bridge with pulse-width-modulation and phase-shift control for hybrid renewable energy systems. In the proposed topology, the switches are driven by phase-shifted PWM...... of the proposed ac inductor based TPC is investigated by performing state-space modelling. Moreover, the derived mathematical models are validated by simulation and measurements. In order to verify the validity of the theoretical analysis, design and power decoupling control scheme, a prototype is constructed...

  14. Safety and durability of municipal road and bridge design%市政路桥设计中的安全性和耐久性研究

    Institute of Scientific and Technical Information of China (English)

    曲志严

    2015-01-01

    The design is directly related to the quality of roads and bridges, a lot of infrastructure problems are not resolved, it will affect the bridge's safety and durability. In this paper, the current problems are simple analysis, for which the work done and the corresponding question briefly, hoping to learn from.%设计直接关系到路桥的质量问题,很多基础问题不解决,就会影响路桥的安全性及耐久性。本文对当前的问题进行了简单分析,对于其中的工作以及相应的问题做了简单介绍,希望能有所借鉴。

  15. Optimal Design of 3-ton Fork-lift Horizontal Style Turning Bridge%三吨叉车横置式转向桥的优化设计

    Institute of Scientific and Technical Information of China (English)

    王彩芹; 何秀彬

    2001-01-01

    叙述了3 t平衡重式叉车横置油缸转向桥的结构设计,主要包括横置油缸式转向桥的结构参数的确定及其转角精度的核定,从而实现转向系统的技术参数的要求。%The paper describes the structure design of horizontal style oil cylinder turnin g bridge of 3-ton balance weight type fork-lift, which mainly includes the det ermining of structural parameters of oil cylinder type turning bridge and of th e rotary angle precision checking. Thus, the technical parameters' requ irements are met with the turning system.

  16. The Design and Construction of Cable Crane of Glass Channel Bridge%玻璃沟大桥缆索吊机设计与施工

    Institute of Scientific and Technical Information of China (English)

    王鸽; 肖稀; 曾建伟; 吴智宇

    2014-01-01

    以玻璃沟大桥为背景,对工作主索、起重索、锚梁、牵引索的设计进行了详细的分析计算,并介绍了吊运缆索吊机承重主索的工作原理,对高原上类似桥梁的施工具有一定的参考价值。%Based on the glass channel bridge, this paper analyzes and calculates the design of the main cable, the hoisting cable, anchor beam and cable in detail, and introduces the working principle of lifting cable crane load bearing cable, which provides a certain reference for the similar bridge construction on the plateau.

  17. Design of (70+125+70) m Continuous Girder Bridge by Swing Method Crossing above Existing Railways%(70+125+70)m跨铁路转体连续梁桥设计

    Institute of Scientific and Technical Information of China (English)

    刘润舟

    2013-01-01

    Crossing above both the Nanchang-Jiujiang Intercity Railway and Beijing-Kowloon Railway, the main bridge of Gong’an Bridge is a continuous prestressed concrete girder bridge with the span arrangement of (70+125+70)meters. This thesis introduced how to select the bridge site and bridge type, how to design the bridge structure, how to select the calculation parameters, and how to erect the girder by swing method. Meanwhile, by using finite element software named Dr. Bridge, the bridge structure was calculated and analyzed longitudinally and transversely, and the results show that all the structural strengths, stresses, displacements, etc. can accord with the relevant provisions of the design codes.%共安大桥主桥上跨昌九城际、京九铁路,采用(70+125+70) m预应力混凝土连续梁,对桥位和桥型确定、桥梁结构设计和计算参数选取,以及转体施工方案进行介绍。采用有限元软件桥梁博士对桥梁结构进行纵向计算分析,结果表明结构强度、应力、位移等均满足设计规范的有关规定。

  18. 北京某矮塔斜拉桥的设计与施工实践%Study on Design and Construction of one Extradosed Cable-Stayed Bridge in Beijing

    Institute of Scientific and Technical Information of China (English)

    庄年; 应伟强

    2011-01-01

    The main bridge of Tongzhou Yudaihe Bridge is a kind of prestressed concrete extradosed cable-stayed bridge with four span three pylon and double-cable-plane. Spans are attributed as (45 + 85 + 85 +45) m. The middle tower girder and pier are fixed. The side tower girder and pier are separated and supports mounted on the top of pier. Taking this bridge as an example, the characteristics of bridge type and force principle of the extradosed cablestayed bridge are simply analyzed. In this paper, the design conception and design gist of this type bridge are mainly introduced, and the construction scheme and construction techniques of this bridge are discussed.%北京通州玉带河大桥主桥为4跨3塔双索面预应力混凝土矮塔斜拉桥,主桥孔跨为45+85+85+45m,采用中塔塔梁固结、边塔塔梁与墩分离、墩顶设支座的结构形式.本文以该桥为例,浅析了预应力混凝土部分斜拉桥的桥型特点、受力特性,主要介绍了该类桥型的设计构思及要点,论述了该桥施工方案的选择及施工要点.

  19. Study on restrainer design method for continuous bridges%连续梁桥缆索限位器设计方法

    Institute of Scientific and Technical Information of China (English)

    张华; 李建中; 彭天波

    2013-01-01

    The method to define the maximum available relative displacement (MARD) of girder bridges is presented first. Based on the existing restrainer design methods for in-span hinges of frame bridges, different simplified mechanical models are proposed according to the different characteristics and positions of the expansions of continuous bridges with laminated rubber bearings. The nonlinear properties of sliding between laminated rubber bearings and main girders, restrainers and expansion gap are included in the simplified models. The restrainer design method for each simplified model is proposed. The effectiveness of the design methods is verified by designing restrainers for an example bridge. The results from nonlinear time history analysis show that restrainers determined by the methods perform well and effectively prevent unseating of the bridge. Meanwhile the seismic demands of the piers with restrainers are increased.%首先提出了梁桥有效搭接长度的确定方法.在参考国外缆索限位器设计方法的基础上,针对采用板式橡胶支座的连续梁桥,根据不同伸缩缝位置的约束特点,提出了对应的简化力学分析模型.简化模型考虑了板式橡胶支座滑动、缆索限位器和伸缩缝约束作用的非线性特性,在此基础上提出了不同伸缩缝位置处相应的缆索限位器设计方法.采用该方法对某桥进行了缆索限位器设计,并用非线性时程分析方法对限位器设计方法的有效性进行了评估.结果表明,所提设计方法能够有效地设计约束伸缩缝处墩梁相对位移的缆索限位器刚度,但设置缆索限位器后过渡墩的抗震要求有一定的增加.

  20. 道路桥梁设计隐患问题及完善措施%On the Problems and Improvement Measures in Road and Bridge Design

    Institute of Scientific and Technical Information of China (English)

    王玲

    2016-01-01

    The problems in road and bridge design are introduced,and the analysis of the causes of these problems is put forward.Combining with engineering examples,measures to improve the design of roads and bridges are put forward in the paper,including ensuring the safety and durability of the structure,improving the material quality,prolonging service life,paying attention to the road and bridge maintenance and condition monitoring and maintenance,and improving the content of construc-tion technology.The practical application shows that the above measures can effectively prevent the safety hazards,ensure the quality of road and bridge engineering,and improve the comprehensive ben-efits.%针对道路桥梁设计存在的安全隐患,分析产生问题的成因。结合工程实例,提出道路桥梁设计的完善措施,包括确保结构安全性与耐久性、提高材料质量、延长工程使用寿命、重视道路桥梁监测维修及养护、改进施工技术等内容。实际应用表明,采取上述措施能有效预防安全隐患,确保道路桥梁工程质量,提高综合效益。

  1. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way.......In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way....

  2. 结合梁桥面系异形钢箱拱肋系杆拱桥设计%Design of Special-shaped Steel Box Arch Rib Bowstring Arched Bridge of Bonding Beam Deck System

    Institute of Scientific and Technical Information of China (English)

    李文勃

    2009-01-01

    The main bridge of Putian Chenggang Avenue Bridge crossing Molan River is the special-shaped bowstring arched bridge of 2-span simple-supported double-rib half-through steel box arch rib bonding beam deck system. The single span is 72 m long and the bridge is 47.5 m wide with city-Class A load and double-direction of 8 lanes. Taking the preliminary design and construction drawing design of this bridge as the basis, the article introduces the scheme study of bridge type, structural design of main bridge and analysis of structural calculation of the special-shaped bowstring arched bridge, and analyzes some technical characteristics of this bridge. The design method of the main bridge inclined crossed with the curve river, the design thinks of bonding beam in the arched bridge, the temporary constructed supporting point for improving the structural bearing, and the design method of special arch rib modeling can be referred for the design of the similar bridges.%莆田城港大道跨木兰溪大桥主桥是两跨简支的双肋下承式钢箱拱肋结合梁桥面系的异形系杆拱桥,单跨跨径72m,桥宽47.5m,城一A级荷载,双向8车道.该文以该桥的初步设计和施工图设计为基础,介绍了异形系杆拱桥的桥型方案研究、主桥结构设计、结构计算分析等内容,并分析了该桥的一些技术特点.该桥的弯曲河道斜交主桥设计方法、结合梁在拱桥中的设计思想、结合梁横梁设置临时支点改善结构受力、独特拱肋造型的设计方法等内容,可供类似桥梁设计时参考.

  3. Programmevaluierung Bridge

    OpenAIRE

    Warta, Katharina; Good, Barbara; Geyer, Anton

    2009-01-01

    BRIDGE is an initiative funded by the Ministry for Transport, Innovation and Technology (BMVIT) that aims to close the “funding gap” between basic and applied research in stand-alone projects with the primary objective of jointly developing the potential of basic and applied research. BRIDGE acts as an  umbrella structure under which the Austrian Science Fund (FWF) and the  Austrian Research Promotion Agency (FFG) coordinate two thematically open funding programmes: The ...

  4. 沪蓉高速公路铁罗坪大桥设计%Design of Tieluoping Bridge on Shanghai-Chengdu Expressway

    Institute of Scientific and Technical Information of China (English)

    郭安辉; 张门哲

    2012-01-01

    铁罗坪大桥主桥为预应力混凝土双塔双索面斜拉桥,跨径布置为(140+322+140)m.该桥主梁基本断面形式为边主梁;桥塔为H形,总高190.397 m,塔柱采用空心五边形断面,在上塔柱锚固区采用U形预应力束加强,桥塔墩基础由24根φ2.4m的桩基组成;每个桥塔两侧布置19对斜拉索,斜拉索采用低松弛镀锌高强钢丝.从温度作用、汽车荷载作用、成桥阶段稳定系数方面对2种结构体系(墩塔梁固结体系和飘浮体系)进行比选,最终选择了对结构受力更为有利的墩塔梁固结体系.采用MIDAS Civil软件分别对该桥静、动力特性、抗风稳定性及地震反应进行分析,分析结果表明结构受力均满足规范要求.该桥主梁采用悬臂浇筑施工,合龙顺序为先边跨、再中跨.%The main bridge of the Tieluoping Bridge on Shanghai-Chengdu Expressway is a prestressed concrete cable-stayed bridge with double pylons, double cable planes and with span arrangement (140 + 322 + 140) m. The basic section of the main girder of the bridge is the section of edge main girders and the pylons are the H-shape ones, each being 190. 397 m in total height. The columns of a pylon were designed as the hollow pentagonal sections and in the anchorage zones in the upper parts of the columns, the U-shape prestressing strands were employed to reinforce the zones. A foundation for the pylon piers is composed of 24 nos. of f2. 4 m piles. On both sides of a pylon, 19 pairs of stay cables, made up of the low relaxation and high-strength galvanized steel wires, were arranged. Two kinds of the structural systems of the rigid fixity system of pier, pylon and girder and the floating system were compared from aspects of the temperature action, truck load action and stability coefficients of the completed bridge and eventually, the rigid fixity system that is more advantageous to the structural force conditions of the bridge was chosen. The software MIDAS Civil was

  5. Modelling railway bridge asset management

    OpenAIRE

    Le, Bryant Linh Hai

    2014-01-01

    The UK has a long history in the railway industry with a large number of railway assets. Railway bridges form one of the major asset groups with more than 35,000 bridges. The majority of the bridge population are old being constructed over 100 years ago. Many of the bridges were not designed to meet the current network demand. With an expected increasing rate of deterioration due to the increasing traffic loads and intensities, the management authorities are faced with the difficult task of k...

  6. Explosion on the reinforcement design and construction methods of stone arch bridge%石拱桥加固设计及施工方法探讨

    Institute of Scientific and Technical Information of China (English)

    周勇

    2015-01-01

    结合工程案例,对拱背增大截面加固石拱桥的设计方案进行了介绍,并对拱上建筑拆除、主拱圈加固、更换拱腔填料等施工工艺进行了阐述,通过实践证明,采用该加固方法既可大大减少工程投资,又能提高石拱桥的整体承载能力,具有显著的社会和经济效益,对石拱桥的加固具有积极的推广意义。%Combining with engineering examples,the paper introduces the design scheme of arch enlarging section reinforced stone arch bridge, and describes top arch building demolishment,main arch circle reinforcement,and replacing arch filling materials and other construction technol-ogies. Practice proves that:the reinforcement methods can not only reduce engineering investment,but also improve integral bearing capability of stone arch bridge,and has obvious social and economic benefits,which has positive meaning for reinforcing stone arch bridge.

  7. On exploration for design and construction of large span bridges%大跨径桥梁设计与施工探讨

    Institute of Scientific and Technical Information of China (English)

    孙泽军

    2012-01-01

    通过借鉴已建大跨径桥梁设计施工先进经验,提出了大跨径桥梁建设在设计中应注重前期工作和专题研究,不断提高自主创新设计和计算机辅助设计能力,重视结构耐久性和工程的质量、安全、环保和美学问题;在实际施工中施工单位应提高施工实力和科研能力,自主创新施工工艺、方法,以确保预应力施工质量和有效监测监控。%Based on the advanced experience for the design and the construction of the established large span bridge, the paper points out some attentive preparation and monographic study on the design for the large span bridges, improves the self innovative design and the design capacity assisted by computers, emphasizes the structural durability and the quality, the safety, the environment paotection and aesthetic issues, and en hances the construction capacity and the scientific research of the construction parties in the factual construction, and invents new construction craft, so as to ensure the presstressed construction quality and the effective supervision.

  8. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2005-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  9. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2004-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  10. Vulnerability of bridges to fire

    DEFF Research Database (Denmark)

    Giuliani, Luisa; Crosti, C.; Gentili, F.

    2012-01-01

    Even if recent effort in developing methodology and measures for design structures against fire and explosions has been mostly focused on buildings, bridges can also be very sensitive to those actions, as witnesses by some recent bridge accidents, which caused major economic losses and also...... endangered people safety in few cases. Purpose of this paper is making a focus on the state of the art of the research and current regulations concerning the response of bridges to fire. Several cases of bridge fires are reported and a focus is made on the occurrence and consequence of bridge fires......, considering both the costs deriving by structural damages and by limited serviceability and other indirect societal aspects. Few cases of recent bridge fire are reviewed in detail and structural consequences are highlighted, distinguishing between damages directly induced by fire and damages induced by local...

  11. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

    Department of Homeland Security — The NBI is a collection of information (database) describing the more than 600,000 of the Nation's bridges located on public roads, including Interstate Highways,...

  12. Comparison between Modern Violin Bridge and Baroque Violin Bridge by Photoelastic Observation and Frequency Analysis

    Science.gov (United States)

    Matsutani, Akihiro

    2004-05-01

    A comparison between the modern bridge and the baroque bridge of the violin by photoelastic observation was carried out. The relationship between the stress part and the hole is symmetric in the modern and baroque bridges. The measured spectral envelopes of baroque bridges are similar to those of modern bridges in D- or G-strings, and have peaks at a frequency higher than those of modern bridges in E-string. The visualization method as used in this study may provide hints for the design of violin bridges.

  13. A designed 5-fluorouracil-based bridged silsesquioxane as an autonomous acid-triggered drug-delivery system.

    Science.gov (United States)

    Giret, Simon; Théron, Christophe; Gallud, Audrey; Maynadier, Marie; Gary-Bobo, Magali; Garcia, Marcel; Wong Chi Man, Michel; Carcel, Carole

    2013-09-16

    Two new prodrugs, bearing two and three 5-fluorouracil (5-FU) units, respectively, have been synthesized and were shown to efficiently treat human breast cancer cells. In addition to 5-FU, they were intended to form complexes through H-bonds to an organo-bridged silane prior to hydrolysis-condensation through sol-gel processes to construct acid-responsive bridged silsesquioxanes (BS). Whereas 5-FU itself and the prodrug bearing two 5-FU units completely leached out from the corresponding materials, the prodrug bearing three 5-FU units was successfully maintained in the resulting BS. Solid-state NMR ((29) Si and (13) C) spectroscopy show that the organic fragments of the organo-bridged silane are retained in the hybrid through covalent bonding and the (1) H NMR spectroscopic analysis provides evidence for the hydrogen-bonding interactions between the prodrug bearing three 5-FU units and the triazine-based hybrid matrix. The complex in the BS is not affected under neutral medium and operates under acidic conditions even under pH as high as 5 to deliver the drug as demonstrated by HPLC analysis and confirmed by FTIR and (13) C NMR spectroscopic studies. Such functional BS are promising materials as carriers to avoid the side effects of the anticancer drug 5-FU thanks to a controlled and targeted drug delivery. PMID:23929826

  14. 跨多股道钢箱梁天桥的结构设计%The Structural Design of Steel Box Girder Pedestrian Bridge Crossing Multiple Railways

    Institute of Scientific and Technical Information of China (English)

    沈耀海

    2011-01-01

    结合西部某新建火车站进站人行天桥工程实例,分析了设计和施工的多种控制条件,论证了主梁采用钢箱梁结构的合理性.通过有限元分析和动力特性计算可知,结构设计的控制因素为竖向自振频率,采用中墩与主梁固结的连接方式可以有效地调整结构竖向自振频率.%Based on the project case of one pedestrian bridge in one new constructed railway station at west China, many controlled conditions are analyzed about structural design and engineering construction, and the rationalitles of steel box girder bridge adopted in the design are also demonstrated. It is learned from finite - element analysis and dynamic characteristics calculation that the control factor of structural design is vertical vibration frequency, which can be improved effectively by means of fixed connection between central pier and steel box girder.

  15. Bridge engineering handbook construction and maintenance

    CERN Document Server

    Chen, Wai-Fah

    2014-01-01

    Over 140 experts, 14 countries, and 89 chapters are represented in the second edition of the Bridge Engineering Handbook. This extensive collection highlights bridge engineering specimens from around the world, contains detailed information on bridge engineering, and thoroughly explains the concepts and practical applications surrounding the subject.Published in five books: Fundamentals, Superstructure Design, Substructure Design, Seismic Design, and Construction and Maintenance, this new edition provides numerous worked-out examples that give readers step-by-step design procedures, includes c

  16. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...... in the Media”, “Audience Interactivity and Participation”, “The Role of Media and ICT Use for Evolving Social Relationships” and “Audience Transformations and Social Integration”. Building Bridges is the result of an ongoing dialogue between the Action and non-academic stakeholders in the field of audience...

  17. The Pylon Design of Long Gang Bridge in Han Zhong%汉中龙岗大桥主塔设计

    Institute of Scientific and Technical Information of China (English)

    张和; 丁燕; 商岸帆

    2014-01-01

    汉中市龙岗大桥主桥为三塔斜拉-自锚式悬索协作体系桥,跨径组合为25 m +90 m +2×162.5 m +90 m +25 m。主桥桥型以“鱼跃龙门”为构思主题,主塔采用“H”型空心薄壁塔身,钢筋混凝土结构;上塔柱拉索锚固区采用“井”字预应力钢筋来平衡拉索水平分力。介绍了主塔造型的景观构思,对桥塔结构特点、结构设计构造、整体计算和拉索锚固区局部应力分析结论进行介绍。%The pylon design of long gang bridge in Han zhong is the he three pylons cable-stayed and self anchored suspension bridge,the span is 25 m +90 m +2 ×162.5 m +90 m +25 m.The main bridge with “leap”for the concept,“H”type hollow thin-walled tower is used in the pylon,and is rein-forced concrete structure.Pylon anchorage zone of the “#”prestressed reinforced to balance the horizontal component of cable.This paper introduces the conception of pylon landscape modeling,on the pylon struc-ture,structure design,calculation and analysis of local stress in Anchorage Zone of the conclusion are in-troduced.

  18. Istanbul Bridge Conference 2014

    CERN Document Server

    Gülkan, Polat; Mahmoud, Khaled

    2016-01-01

      The book includes peer-reviewed contributions selected from presentations given at the Istanbul Bridge Conference 2014, held from August 11 – 13 in Istanbul, Turkey. It reports on the current challenges in bridge engineering faced by professionals around the globe, giving a special emphasis to recently developed techniques, innovations and opportunities. The book covers key topics in the field, including modeling and analysis methods; construction and erection techniques; design for extreme events and condition assessment and structural health monitoring. There is a balanced presentation of theory, research and practice. This book, which provides the readers with a comprehensive and timely reference guide on current practices in bridge engineering, is intended for professionals, academic researchers and students alike.

  19. 矮塔斜拉桥结构力学行为研究与设计实践%Cable Force Optimization and Design Practice of Low Tower Cable-stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    沐云秋

    2016-01-01

    With the development of bridges technology, as a combination bridge between the cable-stayed bridge and continuous girder that cable-stayed bridge with Low Towers is more and more applied, in recent ten years. This bridge belongs to the low tower cable-stayed bridge of pylon girder pier of Twin Towers and double cable plane. Extradited cable-stayed bridge has many mechanical properties are intermediate between the continuous rigid frame bridge and cable-stayed bridge, is by the beam bending, compression and cable tension to bear vertical loads. This design uses the MIDAS/Civil analysis program, provides analysis of data for each part of the design timely, and optimizes the cable which have a surplus volume of safety factor. The girder stress condition is further improved by appropriately adjusting the cable force.%随着桥梁技术的发展,矮塔斜拉桥作为介于斜拉桥和连续梁(刚构)之间的一种组合体系桥型,近十年来应用较多.本桥就属于塔梁墩固结的双塔双索面矮塔斜拉桥.矮塔斜拉桥有许多力学特性都介于连续刚构和斜拉桥之间,是以梁的受弯、受压和索的受拉来承受竖向荷载.本次设计采用MIDAS/Civil分析程,及时为各个设计环节提供分析数据并对安全系数有富余量的拉索进行优化,通过适当调整索力进一步改善主梁的受力状况.

  20. Design of Danyang Road Bridge in Heze City%菏泽市丹阳路大桥设计

    Institute of Scientific and Technical Information of China (English)

    张伟

    2015-01-01

    菏泽市丹阳路大桥为(40+100+240+100+40) m 双塔中央单索面半飘浮体系混凝土斜拉桥。该桥塔、墩固结,主梁与塔、墩间设置横、竖向支座和纵向液压阻尼器;主梁采用单箱三室斜腹板截面,高3.6m。桥塔采用顺桥向人字形的独柱混凝土塔,高68.2m,单箱单室矩形空心截面。人字形塔柱穿过主梁,与墩身顺接,墩身采用十字形空心薄壁截面,矩形承台,布置33根φ2.0m钻孔灌注桩。辅助墩和交接墩均采用花瓶形双柱式框架墩,矩形承台,布置8根φ1.5m钻孔灌注桩。斜拉索采用φ7 mm镀锌高强平行钢丝束。采用MIDAS Civil 2006和SCDS平面程序对该桥进行计算分析,结果表明该桥各项检算均满足规范要求。%T he Danyang Road Bridge in Heze City is a semi‐floating system concrete cable‐stayed bridge with double pylons ,a central single cable plane and with span arrangement (40+100+240+100+40) m .T he pylons and piers of the bridge are rigidly fixed and in betw een the main girder and pylons and piers ,the lateral and vertical bearings and the longitudinal hydraulic damp‐ers are arranged .The cross section of the main girder is the section of triple‐cell single box with in‐clined webs and the girder is 3 .6 m in depth .In the longitudinal direction of the bridge ,a pylon is the single‐column concrete pylon in the shape of inverted Y ,is 68 .2 m in height and the cross sec‐tion of the pylon is the rectangular hollow section of single‐cell single box .The inverted Y‐shape pylon passes through the main girder and is smoothly fixed with the pylon pier .The cross section of the pylon pier is the crisscross hollow thin‐wall section and the pier stands on the rectangular pile cap under w hich 33 nos .of φ2 .0 m bored piles are arranged .T he auxiliary piers and boundary piers are all the vase‐shape double‐column frame piers and respectively stand on each rectangular

  1. Key Techniques for Design of Edong Changjiang River Highway Bridge%鄂东长江公路大桥设计关键技术

    Institute of Scientific and Technical Information of China (English)

    胡明义; 黄冰释; 余俊林; 唐守峰

    2011-01-01

    The main bridge of Edong Changjiang River Highway Bridge is a semi-floating system hybrid girder cable-stayed bridge with double pylons, double cable planes and with a main span 926 m. The main girder of the bridge was designed as the PK (Pasco-Kennewick Bridge) cross section of separated twin boxes, of which the part of the girder for the central span is of the steel box girder, the parts of the girder for the side spans are of the prestressed concrete (PC) box girders and a steel and concrete joint section was set on each side of the central span at a distance of 12. 5 m to the center of a pylon. To ensure a smooth transition between the steel and concrete structure, the multi-cell force transmission structure with PBL shear connectors was used for the joint section. The cable-to-pylon anchorage is the steel anchor box structure built in the column of a pylon. To control the development of concrete cracks in the anchorage zone in the pylon, the prestressing strands of 12φs 15. 24 were set in the concrete pylon wall on the side of the anchorage. To enhance the structural durability and service life, the durability of reinforced concrete and corrosion protection of steel structure were designed and the life cycle cost concept was applide to the design. The inspection and maintenance accesses for all principal components of the bridge were provided and the inspection and maintenance cycles, replacement criteria, workmanship and technical requirements were formulated as well.%鄂东长江公路大桥主桥为主跨926 m的双塔双索面半飘浮体系混合梁斜拉桥,主梁采用分离式双箱PK断面形式,中跨为钢箱梁,边跨为PC箱梁,钢-混凝土结合段设于中跨距桥塔中心12.5m处.为使钢结构与混凝土结构平稳过渡,钢-混凝土结合段采用PBL剪力连接器的多格室传力构造.索塔锚固采用在塔柱内置钢锚箱的构造,为控制锚固区混凝土裂缝开展,在锚固侧混凝土塔壁内设置12(o)s15.24预应力

  2. Design of Hydraulic System for the LTQ-2000Y Passenger Boarding Bridge%LTQ-2000Y型旅客登机桥液压系统设计

    Institute of Scientific and Technical Information of China (English)

    郭会歌; 薛鹏; 杨军宁; 王永利

    2012-01-01

    阐述了旅客登机桥的作用及对液压系统的要求.介绍了LTQ-2000Y型旅客登机桥的液压系统的设计实践,包括油源系统、升降回路、行走回路、转向回路、调平回路、回转回路和应急回路的设计.归纳了该液压系统的主要特点:控制、操作方式多样;油源高效、节能;行走、制动可靠;升降同步、可控;调平自动、及时.这些特点在设备使用中得到了良好的体现.%The passenger boarding bridge's function and its requirement to the hydraulic system were expatiated. The design practices of the LTQ-2000Y passenger boarding bridge's hydraulic system were described, including the design of the oil source system, lifting loop, walking loop, steering loop, leveling loop, rotating loop and emergency loop. The main features of the hydraulic system were generalized; the control and operation modes were varied; oil source was efficient and energy-saving; walking and braking was reliable; up & down lifting was synchronized and controllable; leveling was automatically and timely. These features are well reflected when using the device.

  3. 基于 STM32的全桥逆变器的设计%The Design of Full Bridge Inverter Based on STM32

    Institute of Scientific and Technical Information of China (English)

    黎山峰; 黄超龙

    2016-01-01

    The paper introduces a design of the full bridge inverter based on the STM 32 microcontroller as the controlling core in order to design a low power digital sine-inverter, which uses a high resolution SPWM pulse produced by the MCU ’ s high speed timer , and operates the SPWM pulse into chopper inversion by the photoelectric coupler and IR 2111 to amplify power with the help of the full bridge converter made of IRF 840 , with the LC filtering circuit , finally changing high voltage SPWM pulse into AC power .%为设计一种低功耗的数字化正弦逆变器,设计了以STM32单片机为控制核心的全桥逆变器,该逆变器采由单片机的高速定时器产生高分辨率的SPWM脉冲,通过光耦隔离和IR2111驱动芯片把SPWM脉冲信号对由IRF840场效应管构成的全桥电路实现斩波逆变,经过LC滤波电路,最后实现高压SPWM脉冲转换成交流电源。

  4. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...

  5. Bridged graphite oxide materials

    Science.gov (United States)

    Herrera-Alonso, Margarita (Inventor); McAllister, Michael J. (Inventor); Aksay, Ilhan A. (Inventor); Prud'homme, Robert K. (Inventor)

    2010-01-01

    Bridged graphite oxide material comprising graphite sheets bridged by at least one diamine bridging group. The bridged graphite oxide material may be incorporated in polymer composites or used in adsorption media.

  6. New Concept for Durable Concrete Bridges

    OpenAIRE

    Damek, Marek

    2015-01-01

    This master’s thesis covers the design of a post-tensioned concrete bridge in Trondheim municipality in Norway, in collaboration with Statens vegvesen (SVV). The concept of the bridge is inspired by Egg-Graben-Brücke in Austria, which was designed and built without steel reinforcement in the bridge deck. The idea is to eliminate steel reinforcement which can corrode in the bridge deck. The total length of the bridge is 73 meters and it is divided into 3 spans. The crosssection ...

  7. LLC resonant half-bridge circuit design with DC-DC%LLC谐振半桥DC-DC电路设计

    Institute of Scientific and Technical Information of China (English)

    杨磊; 吴晓光; 羊彦

    2013-01-01

    LED drive power level after the DC-DC constant current circuit using LLC resonant half-bridge topology structure, and through the output current and voltage feedback loop to achieve constant current limiting function.LLC resonant half-bridge DC-DC constant current circuit power part comprises a resonant circuit and the output of the rectifier circuit, the control part chip power supply circuit, the control chip peripheral circuit, an output feedback loop, the test shows that the system has stable output can be good, long time working with high efficiency.%LED驱动电源的后级DC-DC恒流电路采用LLC谐振半桥的拓扑结构,并通过输出的电流电压双环反馈来实现恒流限压功能.LLC谐振半桥DC-DC恒流电路的功率部分包括了谐振电路和输出整流电路,控制部分有芯片供电电路、控制芯片外围电路、输出反馈回路等,经试验证明该系统输出稳定好,能够长时间高效工作.

  8. Modeling and Design of Five Level Cascaded H-Bridge Multilevel Inverter with DC/DC Boost Converter

    Directory of Open Access Journals (Sweden)

    Vinayaka B.C

    2014-06-01

    Full Text Available Power electronic converters, especially DC/AC Sinusoidal Pulse Width Modulation inverters have been extending their range of use in industry because of their numerous advantages. They typically synthesize the stair –case voltage waveform (from several dc sources which has reduced harmonic content. This paper aims to extend the knowledge about the performance of Five level Cascaded H-Bridge MLI topology with DC/DC Boost Converter using SPWM for fixed DC Source. The output voltage is the sum of the voltage that is generated by each bridge. The switching angles can be chosen in such a way that the total harmonic distortion is minimized. This topology incorporates Boost Converter in the input side which magnifies the fundamental output voltage with reduction in total harmonic distortion. It also incorporates LC filter and hence output is drawn near the sine wave because of more levels. Results of experiments proved efficiency of 95%.The performance of the proposed SPWM strategy in terms of output voltage and THD has studied successfully and shown using MATLAB/Simulink.

  9. Optimum selection on bridge erection with floating crane in East China Sea Bridge and Hangzhou Bay Bridge

    Institute of Scientific and Technical Information of China (English)

    Shunquan Qin; Pu Zhou; Youheng Hua

    2004-01-01

    @@ Introduction With the rapid development of China′s economy, many bridges will be built over the Chinese coastal waters of Pacific Ocean. Among them, construction of East China Sea Bridge has been commenced in June 2001, and will be completed at the end of 2005, Hangzhou Bay Bridge was also started to construct in June 2003(Fig. 1). These two ultralong bridges are designed as twin expressway bridges standing side by side each carries a 3-lane one-way carriageway. The total width is 31.5m and 33.0m respectively. East China Sea Bridge starts from Nanhui District, Shanghai and extends to the Yangshan Deep Water Port Area, which is located at one of the Qiqu Islands. The total length of the bridge is about 31.0 km, in which 25 km are on the sea, and 22 km is in the unnavigable region. Hangzhou Bay Bridge across the mouth of Qiantang River.

  10. Analysis of Highway Concrete Beam Bridge Life Cycle Design Method and Application%公路混凝土梁式桥全寿命设计方法及应用分析

    Institute of Scientific and Technical Information of China (English)

    陈锦辉

    2012-01-01

    目前国内外虽然进行了大量针对桥梁生命周期的专项研究,但关于桥梁全寿命设计体系、各设计过程及相应方法的研究依然匮乏。现阐明了全寿命设计方法的概念、设计原则和设计目标,将桥梁的设计和需求拓展到结构的整个使用寿命期,建立了公路混凝土梁式桥全寿命设计方法的总体框架。同时以一座钢筋混凝土简支梁桥作为背景工程,从桥梁时变可靠性和周期成本优化两个方面入手,将所研究的全寿命设计框架和设计方法进行了具体阐述,并应用于实际混凝土梁式桥项目中,为工程实践提供一定的参考借鉴和设计思路。%Although a great deal of special research on the bridge life cycle has been done at home and abroad, the life cycle design system and the corresponding design methods for bridge are still scarce. The concept of life cycle design methods, design principles and design objectives are clarified. The design of the bridge and needs are expanded to the entire life of the structure. The overall framework of the life cycle design of the highway concrete beam bridge is created in this paper. An example is studied based on simply supported reinforced concrete beam bridge engineering. A life cycle design framework and design method for the life cycle design system of bridge are specifically addressed, according to the two methods including the time-variant reliability and cycle cost optimization for the bridge. The theory is applied to actual concrete beam bridge project for engineering practice to provide references and design ideas.

  11. Military Beam Temporary Bridge Design Crossing over Railway in Electrification Innovation of Existing Line%铁路电气化改造中上跨军用梁公路便桥设计

    Institute of Scientific and Technical Information of China (English)

    肖念婷

    2014-01-01

    In electrification Innovation of existing railways, some road bridges crossing over railway need be demolished and re-constructed because of the insufficient clearance under the bridges, it introduces the analysis and check-calculation of temporaty bridge design by the 64-type military beam,which could be for technical assurance on temporaty bridge operation safety.%结合某铁路电气化改造中既有上跨公路桥因净空不足需拆除重建,介绍采用64军用梁架设公路便桥的设计方案,并进行分析和检算,为便桥运营安全作出技术上的保证。

  12. Development of cooperative system bridges

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhe; WAN Qi-bai; SHI Lei

    2008-01-01

    Cooperative system bridges comprise several basic structures that act jointly to improve structural characteristics. We delved into the historical development of cooperative system bridges. Cooperative systems are classified as different-load cooperative systems and same-load cooperative systems by distinguishing the modes of load distribution. For different-load cooperation, individual basic structures are at different positions in the direction along bridge axis and carry the loads separately. While for same-load cooperation, all basic structures overlap in geometrical locations and support the entire loads conjointly. The choosing of span ratios between basic structures, the design of connections of different-load cooperative systems were discussed as well as optimizations of relative rigidity for same-load cooperative systems which greatly influence structural characteristics. The general situation and several structural measurements of several cooperative bridges were demonstrated. This information can assist engineers in developing their concepts in cooperative systems and can lead to more efficient and economical cooperative bridges.

  13. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents

    Science.gov (United States)

    Duan, Yong-Tao; Man, Ruo-Jun; Tang, Dan-Jie; Yao, Yong-Fang; Tao, Xiang-Xiang; Yu, Chen; Liang, Xin-Yi; Makawana, Jigar A.; Zou, Mei-Juan; Wang, Zhong-Chang; Zhu, Hai-Liang

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide–bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, 1H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential. PMID:27138035

  14. 跨接在两个网络间的语音记录仪设计%Design of audio recording system bridged on two network

    Institute of Scientific and Technical Information of China (English)

    徐智敏; 颜浩洋; 王建兵; 喻德茂

    2015-01-01

    设计了语音记录仪。该语音记录仪桥接在通信设备之间,同时提供3种桥接接口:以太网接口,支持在 IP 通信方式下的各通话组的直通及录音功能;二线接口,支持模拟二线方式下的直通及录音功能;音频接口,支持模拟音频方式下的直通及录音功能。同时话音记录仪提供 FTP 服务器,可以通过局域网对语音记录仪保存的语音文件进行下载和管理。此外,该设备支持语音回放功能。%An audio recording system was designed in this article which was bridged on the communication device. It provided three bridge means. Ethernet: the audio record and voice call over IP was supplied. 2-wire: voice call on the 2-wire and the audio record was supplied. Audio: the analog audio and the audio record was supplied. The FTP server was supplied. The audio document could be downloaded and managed through the LAN. The device also has the audio replay function.

  15. Structural criteria for the rational design of selective ligands. 2. Effect of alkyl substitution on metal ion complex stability with ligands bearing ethylene-bridged ether donors

    Energy Technology Data Exchange (ETDEWEB)

    Hay, B.P.; Zhang, D.; Rustad, J.R. [Pacific Northwest National Laboratory, Richland, WA (United States)

    1996-04-24

    A novel approach is presented for the application and interpretation of molecular methanics calculations in ligand structural design. The methodology yields strain energies that (i) provide a yardstick for the measurements of ligand binding site organization for metal ion complexation and (ii) allow the comparison of any two ligands independent of either the number and type of donor atoms or the identity of the metal ion. Application of this methodology is demonstrated in a detailed examination of the influence of alkyl substitution on the structural organization of ethylene-bridged, bidentate, ether donor ligands for the alkali and alkaline earth cations. Nine cases are examined, including the unsubstituted ethylene bridge (dimethoxyethane), all possible arrangements of individual alkyl groups (monoalkylation, gem-dialkylation, meso-dialkylation, d,l-dialkylation, trialkylation, and tetraalkylation), and both cis and trans attachments of the cyclohexyl group. The calculated degree of binding site organization for metal ion complexation afforded by these connecting structures is shown to correlate with known changes in complex stability caused by alkyl substitution of crown ether macrocycles.

  16. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents.

    Science.gov (United States)

    Duan, Yong-Tao; Man, Ruo-Jun; Tang, Dan-Jie; Yao, Yong-Fang; Tao, Xiang-Xiang; Yu, Chen; Liang, Xin-Yi; Makawana, Jigar A; Zou, Mei-Juan; Wang, Zhong-Chang; Zhu, Hai-Liang

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide-bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, (1)H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential. PMID:27138035

  17. Design and Construction of Concrete Mixture Ratio for Steel Tube Arch Bridge%钢管拱桥混凝土配合比设计与施工

    Institute of Scientific and Technical Information of China (English)

    孙小伟

    2015-01-01

    西藏昌都澜沧江大桥为大跨度、薄壁钢管混凝土拱桥,其钢管混凝土施工采用泵送顶升法,施工难度大,对混凝土性能要求高。经混凝土配合比设计与优化,制备出满足设计要求的C50微膨胀钢管混凝土,并进行混凝土的拌合物性能、物理力学性能及微观结构分析研究,结果表明,所配制的混凝土不离析、不泌水,坍落度23 cm,混凝土拌和物3 h后的坍落度不小于18 cm,混凝土具有早强、高弹性模量和补偿收缩等性能,完全满足西藏昌都澜沧江大桥钢管混凝土拱桥的工程设计及施工要求。%The Qamdo Lancang river bridge of Tibet is big span, thin-walled concrete-filled steel tube arch bridge. The concrete filled steel tube uses pumping jack-up construction method, which is difficult in construction and has high performance requirements of concrete. Through concrete mixture ratio design and optimization, C50 micro expansive concrete filled steel tube is prepared to meet the design requirements, and the mixture performance physical and mechanical properties and microstructure analysis of concrete are studied. The results show that the mixed concrete has no segregation and no bleeding, 23 cm slump. The slump of concrete mixing content after 3 h is no less than 18 cm. Concrete has high early strength, elastic modulus and shrinkage compensation, fully meeting the engineering design and construction requirements of the bridge.

  18. Design and construction of scour protection for deep-water group pile foundation structures of two pylons in the Sutong Bridge project

    Institute of Scientific and Technical Information of China (English)

    He Ping; Guan Yijun; Zhang Xiongwen; Zhang Qun; Zhou Jianhua

    2009-01-01

    Sutong Bridge, as a world-record cable-stayed bridge with its main span exceeding 1 000 m constructed in Yangtze River estuary region in China, is located at a site with complicated hydrologic conditions and poor geotechnical conditions and therefore, scour protection will be a decisive factor for ensuring smooth and successful construction of this bridge. This paper, starting from structural description of deep-water group pile foundation, analyzes impact to the bridge safety introduced by scour and its protection and further presents different solutions of scour protection for foundation structures of this bridge.

  19. 汶川地震桥梁震害经验及抗震研究若干新进展%Lessons Learned from Wenchuan Seismic Damages and Recent Research on Seismic Design of Highway Bridges

    Institute of Scientific and Technical Information of China (English)

    王东升; 孙治国; 郭迅; 李晓莉; 霍燚

    2011-01-01

    The great Wenchuan earthquake, which measured as 8. 0 Ms and occurred on May 12, 2008 in Sichuan province of China, has caused severe damage to many highway bridges and also left us with valuable information that can be analyzed to reduce potential losses associated with future earthquakes. The Lessons learned from Wenchuan seismic damages of highway bridges were summarized. It is believed that special attention should be paid to (1) bridge seismic response and unseating damages subjected to near-fault ground motions; ( 2 ) preventive design of collapse damage of curved girder bridges with small radius; ( 3 ) ductility and seismic design, detailed reinforcement of bridges and seismic damage control of high-rise piers under deep water. The recent research progress of our research team on seismic performance of highway bridges was summarized. It includes design idea and method of unseating protection of highway bridges, deformation capacity and shear strength of PC bridge piers, numerical simulation of seismic damage mechanism of curved girder bridges, and countermeasures to prevent collapse of curved girder bridges with small radius.%2008年5月12日我国四川省汶川县发生8.0级大地震,造成大量公路桥梁破坏,并为桥梁抗震研究留下了众多资料.总结了汶川地震桥梁震害经验,认为宜重视桥梁近断层地震动响应及防落梁措施、小半径曲线梁桥地震防倒塌设计、桥梁延性抗震设计及细部配筋和深水高桥墩地震损伤及控制等抗震问题.综述了课题组近些年对桥梁抗震研究的若干新进展,包括梁式桥防落梁抗震设计理念及方法、钢筋混凝土桥墩地震抗剪强度及变形能力研究、曲线梁桥地震破坏机理数值分析与小半径曲线梁桥地震防倒塌设计对策等.

  20. Thermal bridges of modern windows

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Møller, Eva B.; Nielsen, Anker;

    2013-01-01

    With its focus on reduced energy consumption, contemporary housing construction requires a highly insulated and airtight building envelope with as few thermal bridges as possible.Windows must be carefully designed, as thermal bridges can lead to surface condensation or mold growth, even...... if the window has an U-factor of 1 W/(m2·K) or lower. This paper describes the development of modern, energy efficient Danish windows with reduced thermal bridges. It focuses on materials, geometry, and sealing of window panes based on a literature review. Examples of modern windows are presented. Experience...

  1. Design and Risk Evaluation of Highway Bridges under Effect of Railways and Flood%铁路及洪水影响下的公路桥梁设计与风险评估

    Institute of Scientific and Technical Information of China (English)

    王鹏; 王美馨; 汪宏; 李琦

    2014-01-01

    某高速公路桥梁与3座高速铁路桥梁交叉,公路桥梁下穿铁路桥梁,同时跨越嘉陵江支流,其建设、施工及运营安全受铁路施工、运营及嘉陵江洪水的影响,洪水位高出桥面最大约4.1 m。针对这一极端复杂环境条件,探讨公路桥梁结构及防、排水设计要点,研究桥梁建设条件、结构方案、施工、运营的主要风险源、风险等级及对策。%Some expressway bridge crosses with 3 high-speed railway bridges and railway bridges pass underneath, and meanwhile steps over branches of Jialing River, its development, construction and operation safety is affected by railway construction, operation and flood of Jialing River, the maximum flood level higher than the bridge deck is approximate 4. 1 m. In allusion to this extremely complicated environmental condition, this paper probes into key points in design of structure, water resistance and drainage of highway bridges and studies construction conditions, structure schemes of bridges and main risk sources and levels in construction and operation as well as countermeasures.

  2. Design and Construction of In-water Steel trestle for Shiliugang Bridge%石榴岗大桥水中钢栈桥设计与施工

    Institute of Scientific and Technical Information of China (English)

    简健泰

    2009-01-01

    通过广州市南部快速路SD1标石榴岗大桥水中钢栈桥与钢平台的施工实践,该文简要介绍了水中临时钢栈桥的设计、计算与施工,为以后同类型工程施工提供相应的参考.%According to the construction practice of the in-water steel trestle and the steel platform of Shiliugang Bridge in Guangzhou City Southern Expressway SDI Bid, the article briefly introduces the design, calculation and construction of the temporary in-water steel trestle, which can provide the relative reference for the construction of the similar projects.

  3. Rational design, synthesis, and biological evaluation of lactam-bridged gramicidin A analogues: discovery of a low-hemolytic antibacterial peptide.

    Science.gov (United States)

    Mao, Ji; Kuranaga, Takefumi; Hamamoto, Hiroshi; Sekimizu, Kazuhisa; Inoue, Masayuki

    2015-03-01

    A linear peptide, gramicidin A (GA), folds into a β(6.3) -helix, functions as an ion channel in the cell membrane, and exerts antibacterial activity. Herein we describe the rational design, synthesis, and biological evaluation of lactam-bridged GA analogues. The GA analogue with a 27-membered macrolactam was found to adopt a stable β(6.3) -helical conformation and exhibits higher ion-exchange activity than GA. Furthermore, this GA analogue retains the potent antibiotic activity of GA, but its hemolytic activity and toxicity toward mammalian cells are significantly lower than those of GA. This study thus dissociates the antibacterial and hemolytic/cytotoxic activities of GA, and charts a rational path forward for the development of new ion-channel-based antibiotics. PMID:25510221

  4. Applications of overburden conveyor bridges

    Energy Technology Data Exchange (ETDEWEB)

    Schachtschneider, H.

    1987-06-01

    In large scale surface mines of the capacities required today, a cross-pit operation with overburden conveyor bridges is the most economical method of overburden removal and disposal. In order to provide the production capacity required in surface mining equipment by the GDR brown coal industry, VEB Schwermaschinenbau Lauchhammerwerk undertook the design and manufacture of standard overburden conveyor bridges for cut heights of 34 m, 45 m and 60 m. All three base types may be equipped to match the site specific geological and geotechnical conditions, and to meet customer's demands. Specifications of the bridges are given as well as details of conveyor belt speeds, modifications to the standards, and number manufactured. Design problems faced with the 60 m bridge are discussed, together with details of the superstructure, method of operation, transportation rates, structural steel used, assembly and power supply. 5 refs.

  5. Inspection method of cable-stayed bridge using magnetic flux leakage detection: principle, sensor design, and signal processing

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Fengyu; Wang, Xingsong [Southeast University, Nanjing (China); Wu, Hongtao [Nanjing University of Aeronautics and Astronautics, Nanjing (China)

    2012-03-15

    A nondestructive testing technique based on magnetic flux leakage is presented to inspect automatically the stay cables with large diameters of a cable-stayed bridge. Using the proposed inspection method, an online nondestructive testing (NDT) modular sensor is developed. The wreath-like sensor is composed of several sensor units that embrace the cable at equal angles. Each sensor unit consists of two permanent magnets and a hall sensor to detect the magnetic flux density. The modular sensor can be installed conveniently on cables with various diameters by increasing the number of sensor units and adjusting the relative distances between adjacent sensor units. Results of the experiments performed on a man-made cable with faults prove that the proposed sensor can inspect the status signals of the inner wires of the cables. To filter the interfering signals, three processing algorithms are discussed, including the moving average method, improved detrending algorithm, and signal processing based on a digital filter. Results show that the developed NDT sensor carried by a cable inspection robot can move along the cable and monitor the state of the stay cables.

  6. Inspection method of cable-stayed bridge using magnetic flux leakage detection: principle, sensor design, and signal processing

    International Nuclear Information System (INIS)

    A nondestructive testing technique based on magnetic flux leakage is presented to inspect automatically the stay cables with large diameters of a cable-stayed bridge. Using the proposed inspection method, an online nondestructive testing (NDT) modular sensor is developed. The wreath-like sensor is composed of several sensor units that embrace the cable at equal angles. Each sensor unit consists of two permanent magnets and a hall sensor to detect the magnetic flux density. The modular sensor can be installed conveniently on cables with various diameters by increasing the number of sensor units and adjusting the relative distances between adjacent sensor units. Results of the experiments performed on a man-made cable with faults prove that the proposed sensor can inspect the status signals of the inner wires of the cables. To filter the interfering signals, three processing algorithms are discussed, including the moving average method, improved detrending algorithm, and signal processing based on a digital filter. Results show that the developed NDT sensor carried by a cable inspection robot can move along the cable and monitor the state of the stay cables

  7. Removal of failed crown and bridge.

    Science.gov (United States)

    Sharma, Ashu; Rahul, G R; Poduval, Soorya T; Shetty, Karunakar

    2012-07-01

    Crown and bridge have life span of many years but they fail for a number of reasons. Over the years, many devices have been designed to remove crowns and bridges from abutment teeth. While the removal of temporary crowns and bridges is usually very straightforward, the removal of a definitive cast crown with unknown cement is more challenging. Removal is often by destructive means. There are a number of circumstances, however, in which conservative disassembly would aid the practitioner in completing restorative/endodontic procedures. There are different mechanisms available to remove a failed crown or bridge. But there is no information published about the classification of available systems for crown and bridge removal. So it is logical to classify these systems into different groups which can help a clinician in choosing a particular type of system depending upon the clinical situation. The aim of this article is to provide a classification for various crown and bridge removal systems; describe how a number of systems work; and when and why they might be used. A PubMed search of English literature was conducted up to January 2010 using the terms: Crown and bridge removal, Crown and bridge disassembly, Crown and bridge failure. Additionally, the bibliographies of 3 previous reviews, their cross references as well as articles published in various journals like International Endodontic Journal, Journal of Endodontics and were manually searched. Key words:Crown and bridge removal, Crown and bridge disassembly, Crown and bridge failure. PMID:24558549

  8. Unseating Damage to Simply Supported Bridges during Wenchuan Earthquake and Design Countermeasures%汶川大地震简支梁桥落梁震害与设计对策

    Institute of Scientific and Technical Information of China (English)

    王东升; 王吉英; 孙治国; 李晓莉

    2011-01-01

    The unseating damage to simply supported bridges and their main influencing factors during the Wenchuan earthquake are summarized. It is found that excepting the earthquake-induced landslide hazard, the earthquake surface rupture, near fault ground motion, punching shear failure of the abutment breast wall, the invalidity of the devices for preventing unseating damage to the bridges and the complex bridge types are main influencing factors leading to the unseating damage to the simply supported bridges. Basic seismic design idea and method to prevent unseating damage to simply supported bridges are presented in this paper, which include: (1) sliding between bridge girders and cap beams is allowed to reduce the seismic actions concentrated on the bridge piers; (2) cap beams with enough seating length are recommended for sliding between girder and pier to avoid unseating damage; (3) shear keys or cable restrainers should be used as added measures to prevent unseating damage. The design method for simply supported bridges with cable restrainers is illustrated in detail by using current seismic design code for bridges.%总结了5· 12汶川大地震中简支梁桥落梁震害及主要影响因素,发现除地震山体滑坡等地质灾害外,断层地表破裂、近断层地震动效应、桥台胸墙冲切破坏、防落梁构造措施单一及桥梁体型复杂等因素都是引起简支梁桥落粱震害的重要原因.提出了简支梁桥防落梁设计的基本理念及相关技术方案要点为允许墩梁间发生滑移,以降低桥墩承受的地震惯性力,以及盖梁提供允许的最大滑移长度及支座支承宽度,再辅助挡块或拉索限位器等共同防止落粱发生.最后结合现行规范,以拉索限位器为例给出了简支梁桥防落梁设计方法.

  9. 三塔斜拉桥设计参数分析%Analysis of Design Parameters for Three-Pylon Cable-Stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    杨庸; 雷俊卿

    2016-01-01

    To study the mechanical behavior of the three‐pylon cable‐stayed bridge structure , combined with the real design cases of three‐pylon composite girder cable‐stayed bridge projects , the finite element model of three‐pylon composite girder cable‐stayed bridge was established to car‐ry out parametric study on the effect of the measures taken ,such as to superimpose stay cables , install stay cables between pylons ,improve pylon stiffness and add auxiliary piers ,and the varia‐tion law of their load bearing behaviors is concluded .The results of the calculation demonstrate that the load bearing capacity of the intermediate pylon ,main girder and stay cables can be effec‐tively improved by adding superimposed cables ,stiffening cables between pylons and auxiliary piers to side spans ,and the pier‐top horizontal displacement and the mid‐span deflection of the main girder can also be reduced .T he pier‐top displacement can be reduced by enhancing the stiff‐ness of the intermediate pylon .The increase of the stiffness of side pylons has little influence on the structure .The increase of the height of the intermediate pylon is capable of improving the in‐ternal force of the pylons ,but accelerating the pier‐top displacement .T he results of the calculation can provide reference for the design of configuratiion of three‐pylon composite girder cable‐stayed bridge structure .%为研究三塔斜拉桥结构的力学行为特征,为三塔斜拉桥设计提供参考,结合三塔结合梁斜拉桥工程设计实例,建立三塔结合梁斜拉桥的有限元模型,对斜拉索重叠布置、塔间斜拉索、提高桥塔刚度及采用辅助墩等措施进行参数分析,总结其受力行为的变化规律。计算结果显示:设置重叠索、设置塔间加劲索、边跨设置辅助墩可有效改善中塔、主梁、斜拉索受力,减少塔顶水平位移值及跨中主梁挠度值;提高中塔刚度可以减少塔顶位

  10. Optimized design of Changsha Xiangfu road bridge guardrail%长沙市湘府路大桥防撞护栏优化设计

    Institute of Scientific and Technical Information of China (English)

    雷正保; 宁寒

    2014-01-01

    为了得到满足防撞等级为 SA级的长沙市湘府路大桥防撞护栏,根据国内新的护栏评价标准,采用计算机仿真的方法,对长沙市湘府路大桥防撞护栏的碰撞安全性展开了研究。以桥梁护栏尺寸参数为参考基础,以防撞等级为SA级的护栏为研究目标,以2种不同车型为研究工况,采用Pro-e建模以及 VPG和 Ls-dyna软件进行处理,联合运用正交试验设计方法,以小车纵横向最大加速度、纵横向最大速度以及客车最大横向偏移量为考核指标,对控制护栏形状的5个设计变量应用 L16(45)正交试验表安排仿真试验,运用 SPSS对仿真试验结果进行方差分析,找出各因素对结果的影响程度,再结合极差分析的结果[1]来确定大桥防撞护栏的最佳尺寸参数。并通过3种车型来验证其可行性,所得到的最佳尺寸组合是可行的且满足法规评定标准要求。%To meet crash rating for SA level of Changsha City,Hunan Road Bridge crash barrier,based on the evaluation criteria domestic new fence ,through the use of computer simulation methods in Changsha City,Hunan Road Bridge guardrail crash safety studies carried out .With bridge parapet dimensions as a reference base to crash rating for SA-level are fence for research obj ectives in three different models for the study of conditions,mod-eling is made with Pro-e ,VPG and Ls-dyna software for processing ,combined with or-thogonal design method to the maximum acceleration of the car vertical and horizontal , vertical and horizontal to the maximum speed,maximum lateral offset of passenger assess-ment indicators ,the control of the shape of the fence the five design variables ,the applica-tion of L16 (45)orthogonal table arrangements simulation ,simulation results using SPSS for analysis of variance to identify the impact of various factors on the results ,combined with the poor results of the analysis to determine Bridge best guardrail

  11. 丫髻沙大桥桥面系加固设计%Strengthening Design of Floor System of Yajisha Bridge

    Institute of Scientific and Technical Information of China (English)

    陈红

    2013-01-01

    In the light of the deteriorations (the loosening and breaking of the high-strength bolts at connections of part of the stringers and cross beams, the cracking and breaking of part of the connecting angle steels and the cracking in the welding seams at connections of part of the cross beam webs and lower flanges) having occurred in the floor system of the Yajisha Bridge (the main bridge is a three-span half-through continuous concrete-filled steel tube arch bridge with a main span 360 m) in the operation period, the causes leading to the deteriorations were analyzed and the strengthening of the floor system of the bridge was designed. According to the analysis, it was concluded that the main cause leading to the deteriorations was the increase of stress in the cross beams of the floor system and the decrease of fatigue performance of the steel structure caused by the increase of truck load. In the design, the live load criterion for the strengthening of the floor system remained unchanged and the floor system was to be systematically strengthened by adding the crack stopping holes, increasing the sections of the cross beams and longitudinal girders and changing the connecting ways of the stringers and cross beams. Finally, the safety and effectiveness of the strengthening measures were verified by the finite element calculation and tests.%针对丫髻沙大桥(主桥为主跨360 m的三跨连续中承式钢管混凝土拱桥)运营期间桥面系出现的病害(部分纵梁、横梁连接处高强螺栓松动、断裂,连接角钢开裂、断裂,部分横梁腹板与下翼缘连接处焊缝开裂等),进行原因分析及桥面系加固设计.经分析,汽车荷载增加引起桥面系横梁的应力增加,降低钢结构的疲劳性能是引起桥面系病害的主要原因.加固设计活载维持原设计荷载标准不变,通过增设止裂孔,增加钢横梁截面,增设大纵梁,改变纵梁、横梁的连接方式对桥面系进行系统加固,采用有限

  12. 美国焊接桥梁的疲劳设计准则%Fatigue Design Criteria for Welded Bridges in the U.S.

    Institute of Scientific and Technical Information of China (English)

    JohnW.Fisher

    2011-01-01

    Fifty years ago,fatigue design was not considered a serious bridge performance issue in the US.Fatigue design utilized the concept of Iimiting the maximum stress at details by using the R-ratio of minimum/maximum stress and an assumption that the fatigue limit occurred at 2 million cycle.The HS-20 design truck was usd for specific cycles based on the type of road and the average daily truck traffic (ADTT).Fatigue cracks were observed to develop in steel bridges in the late 1960s and early 70's.This development and the results of large scale beam tests on welded details that were carried out between 1967 and 1987 provided a statistically sound data base and established that stress range alone was the only statistical significant design stress.The fatigue provisions adopting stress range were changed by AASHTO in 1974.This meant that only the live load cyclic stress was important.The basic fatigue resistance curves provide a log normal lower bound design basis for fatigue life that is used world wide today.Experience with steel bridges also showed that a rule adopted after WWⅡ whiCH avoided welding to tension flanges,has resulted in extensive web gap cracking from out of plane distortions.During the last decade these small web gaps have resulted in unanticipated brittle fractures as a result of tri-axial stresses even in the absence of fatigue crack growth.%50年前,疲劳设计在美国人看来并非是一个很严重的桥梁性能问题.疲劳设计运用了限制最大应力的概念,即假定疲劳极限发生在2×106次循环荷载时,利用最小应力与最大应力的比R,限制各点的最大应力.根据道路类型与每日平均车流量,采用型号为HS-20的设计车来测定特定周期.在20世纪60年代末至70年代初,发现钢结构桥梁中存在疲劳裂纹.1967-1987年,针对焊接部位进行了大量的梁试验.根据试验结果,统计得到了数据库,并认为应力幅度才是唯一主要的设计应力.1974年,美国AASHTO规

  13. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

    Vibration of a bridge structure due to the passage of vehicles is an important consideration in the design of bridges. Further, a common problem in bridge engineering practice in these years is the upgrading of minor highway bridges (=5-20 m) to carry heavier loads partly due to a tendency...... of heavier trucks moving at larger speeds, and partly because the authorities want to permit transportation of special heavy goods at a larger part of the road net. These needs will in many cases cause the strengthening of the bridges becomes necessary. In order to keep the expenses of such strengthening...... the results obtained using the numerical models given in details in "Heavy Vehicles on Minor Highway Bridges : dynamic modelling of vehicles and bridges". The models are established using a ordinary vehicle which consists of a 48 t Scania with a 3 axle tractor and a 3 axle trailer, joined in a flexible hinge...

  14. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

    Vibration of a bridge structure due to the passage of vehicles is an important consideration in the design of bridges. Further, a common problem in bridge engineering practice in these years is the upgrading of minor highway bridges (=5-20 m) to carry heavier loads partly due to a tendency...... of heavier trucks moving at larger speeds, and partly because the authorities want to permit transportation of special heavy goods at a larger part of the road net. These needs will in many cases cause the strengthening of the bridges becomes necessary. In order to keep the expenses of such strengthening...... the numerical models for the mathematical models of the vehicles and the bridge from which the load amplification factors can be estimated assuming that the dynamic parameters of the vehicles and the modal parameters of the bridge are known....

  15. LLC半桥式谐振变换器参数模型与设计%Parameter Model and Design for LLC Resonant Half-bridge Converter

    Institute of Scientific and Technical Information of China (English)

    王镇道; 赵亚魁; 章兢; 吴旭; 易峰

    2012-01-01

    According to working principle of LLC topology,a mathematical model for LLC resonant half-bridge converter is presented in this paper.On the basis of conversion relations between the best conversion efficiency and wide scope of load changes,leakage inductance,magnetic inductance and resonant capacitance are confirmed according to the proposed model.Also a LLC resonant half-bridge converter is designed.By improving switch frequency to MHz-level,its converter efficiency can reach to 94% either in full or light loader.At the same time,the power density can reach to 500W/in3.Experiment results ultimately verify the correctness of the model and parameter deduction.%根据LLC拓扑结构工作原理,建立了LLC半桥式谐振变换器的数学模型。基于最优转换效率和宽负载变化范围的转换关系,根据模型确定了漏感、励磁电感和谐振电容,并设计了一款LLC半桥式谐振变换器,开关频率提高到兆赫兹级,在轻载和满载时效率均达到94%,功率密度达到500W/in3,实验结果表明了模型和参数设计的正确性。

  16. [Retention of adhesive bridges].

    Science.gov (United States)

    Raes, F; De Boever, J

    1994-04-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rests, interocclusal clearance and cingulum stops is equally important. Including more teeth in the design does not necessarily lead to an improved retention. Besides the material and technical aspects, the whole clinical procedure needs much attention. The retention does not depend on one single factor, but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 80% can be obtained. PMID:11830965

  17. Jacking frame bridge design of near existing line operation high-speed rail%临近既有运营线高铁的顶进框构桥设计

    Institute of Scientific and Technical Information of China (English)

    唐亚芹

    2012-01-01

    通过对临近某高铁下穿立交工程的顶进框构桥的设计介绍,主要阐述了框构桥主体设计、线路加固、线路防护设计、工作坑支护、止水措施设计以及地基加固设计等各个设计细节,本工程的设计可为同类下穿运营铁路立交工程的顶进框构桥设计提供参考。%Through the introduction on jacking frame bridge design of near a high-speed rail under interchange engineering,mainly elaborated the frame bridge body design,line reinforcement,line protection design,working pit support,waterproof measures design and foundation reinforcement design and other all kinds of design details.The project design could provide reference for jacking frame bridge design of similar under operation interchange engineering.

  18. Bridging the gap between selection decisions of facade systems at the early design phase: Issues, challenges and solutions

    Directory of Open Access Journals (Sweden)

    Mohamad Kassema

    2015-11-01

    Full Text Available Building facade has a significant impact on the environmental and economic performance of buildings and projects. The specification of their elements at the early design phase depends on numerous technical, environmental and economic factors and involves several stakeholders. The procurement and delivery of the facade work package from the early design phase, through detailed design and manufacture, to installation is a process with several inherent risk factors due to the involved cost, technical and engineering complexities and its position on the critical path in all projects. This research investigates the process of selection and specification of building facade elements at the early design phases with the overarching aim of identifying the issues affecting specification decisions, their root causes and impact on projects. The research utilizes a mixed research approach which combines a retrospective case study and an industry survey as two research methods that build on each other. The findings suggest that the complexity of specification at the early design phases is exacerbated by factors such as the inadequate technical knowledge of stakeholders involved in the decision making process, the non-involvement of building facade consultants, the late involvement of specialist facade subcontractors, and in a few cases by some commercial exclusivity agreements that restricts specification decisions. 

  19. 牌头浦阳江特大桥深水基础圆形双壁钢围堰设计%Design of Round Double-wall Steel Cofferdam for Deepwater Foundation of Paltoupuyang River Super Bridge

    Institute of Scientific and Technical Information of China (English)

    陈忠

    2012-01-01

    The paper introduces the double-wall steel cofferdam design technique of main bridge deepwater foundation in combination with the construction of deepwater round double-wall steel cofferdam for Paitoupuyang River Super Bridge to provide guidance for construction under similar hydro-geological conditions.%结合牌头浦阳江特大桥跨深静水双壁围堰施工实例,重点介绍主桥深水基础采用双壁钢围堰设计技术,对类似水纹地质条件下施工具有一定的指导意义。

  20. 新抗震规范在高速公路典型桥梁设计中的应用%Application of New Earthquake Resistant Code in Typical Bridge Design for Expressway

    Institute of Scientific and Technical Information of China (English)

    罗波; 李峰

    2012-01-01

    对新桥梁抗震规范在高速公路典型桥梁设计中的应用进行了计算分析,以期达到经济合理和相当安全的抗震目的。%Computational analysis on application of new earthquake resistant code for bridge in typical bridge design for expressway is made so as to achieve the economic and reasonable and comparatively safe earthquake re-sistant aim.

  1. 南平闽江大桥斜拉桥挂篮设计与施工技术%The Design and Construction Technology of Suspension Cradle of Nanping Minjiang Cable-stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    李向海

    2011-01-01

    Based on the practical construction experience of Minjiang Bridge of Nanping City Fujian Province,this paper refers to the main technical solutions and application of front-fulcrum suspension cradle in cable-stayed bridge and the design and construction technology of the suspension cradle.%结合福建省南平市闽江大桥工程实际情况,主要介绍了前支点挂篮在斜拉桥施工中的应用、挂篮的设计与施工技术,以及关键技术问题的解决。

  2. The Wien Bridge Oscillator Family

    DEFF Research Database (Denmark)

    Lindberg, Erik

    2006-01-01

    A tutorial in which the Wien bridge family of oscillators is defined and investigated. Oscillators which do not fit into the Barkhausen criterion topology may be designed. A design procedure based on initial complex pole quality factor is reported. The dynamic transfer characteristic...

  3. Impact of cross-tie design on the in-plane stiffness and local mode formation of cable networks on cable-stayed bridges

    Science.gov (United States)

    Ahmad, Javaid; Cheng, Shaohong; Ghrib, Faouzi

    2016-02-01

    Suppressing unfavorable stay cable vibrations using cross-ties is becoming more popular on cable-stayed bridges though the mechanics of the formed cable network is yet fully understood. In practice, the main task in designing cross-ties or cable networks is to choose the cross-tie installation location, stiffness and number based on the main cable properties in the network. To have a more comprehensive picture of how to choose these design parameters to achieve higher in-plane network stiffness while minimizing the number of excited local modes, it is imperative to examine dynamic behavior of cable networks with general configurations. In the current study, an analytical model of a general cable network consisting of multiple main cables interconnected by multiple lines of transverse flexible cross-ties will be developed. A new term, defined as the local mode cluster, will be introduced to assess the severity of local mode excitation. Criteria for identifying the presence of local mode cluster will be proposed. A parametric study will be conducted to evaluate the impact of cross-tie installation location, stiffness and number on the network modal response. Results obtained from the present study will provide deeper insight into the selection of these system parameters to achieve the combined benefits of increasing network in-plane stiffness and minimizing the excitation of local modes.

  4. 路桥过渡段路基路面设计施工探析%Analysis on the design and construction of subgrade and pavement at highway-bridge transition section

    Institute of Scientific and Technical Information of China (English)

    刘国耘

    2012-01-01

    针对目前高速公路运营过程中存在的桥头跳车等病害,从路桥过渡段路基路面的设计与施工方面进行了论述,并提出减轻桥头跳车的有效措施,对提高公路行车的舒适性和安全性有着重要意义。%In light of bridge head bump and other diseases existing in current highway operation, the paper discusses the design and construction of subgrade and pavement at highway-bridge transition section, and puts forward effective measures for reducing bridge head bump accident, which has significant meaning for improve the comfortableness and security of driving on the highway.

  5. Brief Discussion on Anti-collision Design Example for Piers of Rugao Changqingsha Bridge%浅谈如皋市长青沙大桥桥墩防撞设计实例

    Institute of Scientific and Technical Information of China (English)

    魏东海; 张兆民

    2011-01-01

    With the continuous emergence of large-size bridge along Changjiang water area and rapid increase of ship quantity and tonnage,the safety control project design for navigation span of Rugao Changqingsha Bridge of dredging harbor highway are made to ensure the safety of ship's navigation and bridge facilities.%随着沿长江水域大型桥梁的不断涌现以及船舶数量、吨位的快速增加,为有效保障船舶航行和桥梁设施安全,进行了如皋市疏港公路长青沙大桥通航孔安全保障工程的设计。

  6. Building bridges between theory and practice in medical education using a design-based research approach: AMEE Guide No. 60.

    Science.gov (United States)

    Dolmans, Diana H J M; Tigelaar, D

    2012-01-01

    Medical education research has grown enormously over the past 20 years, but it does not sufficiently make use of theories, according to influential leaders and researchers in this field. In this AMEE Guide, it is argued that design-based research (DBR) studies should be conducted much more in medical education design research because these studies both advance the testing and refinement of theories and advance educational practice. In this Guide, the essential characteristics of DBR as well as how DBR differs from other approach such as formative evaluation are explained. It is also explained what the pitfalls and challenges of DBR are. The main challenges deal with how to insure that DBR studies reveal findings that are of a broader relevance than the local situation and how to insure that DBR contributes toward theory testing and refinement. An example of a series of DBR studies on the design of a teaching portfolio in higher education that is aimed at stimulating a teacher's professional development is described, to illustrate how DBR studies actually work in practice. Finally, it is argued that DBR-studies could play an important role in the advancement of theory and practice in the two broad domains of designing or redesigning work-based learning environments and assessment programs.

  7. Bridging the Field Trip Gap: Integrating Web-Based Video as a Teaching and Learning Partner in Interior Design Education

    Science.gov (United States)

    Roehl, Amy

    2013-01-01

    This study utilizes web-based video as a strategy to transfer knowledge about the interior design industry in a format that interests the current generation of students. The model of instruction developed is based upon online video as an engaging, economical, and time-saving alternative to a field trip, guest speaker, or video teleconference.…

  8. Three Dimensional Analysis of the Final Design of Pier Extensions and West Guide Wall to Mitigate Local Scour Risk at the BNSF Railroad Bridge Downstream of the Prado Dam Supplemental Report

    Energy Technology Data Exchange (ETDEWEB)

    Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Sinha, N. [Argonne National Lab. (ANL), Argonne, IL (United States); Bojanowski, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Kerenyi, K. [Turner-Fairbank Highway Research Center, McLean, VA (United States); Sharp, Jeremy [U.S. Army Corps of Engineers, Vicksburg, MI (United States), Coastal and Hydraulics Lab

    2016-06-01

    This report is a supplement to a previous report [ref] covering optimization of wedge shaped pier extensions to streamline large bluff body piers as a local scour countermeasure for the Burlington Northern and Santa Fe (BNSF) Railroad Bridge over the Santa Ana River downstream of Prado Dam in Riverside County, CA. The optimized design was tested in a 1/30 scale physical model at U.S. Army Engineer Research and Development Center (ERDC) in Vicksburg, MS, and the optimized design was used as the base for the construction design. Constructability issues having to do with both materials and site conditions including access underneath the BNSF bridge yielded a construction design that required making the pier extensions wider and either moving the western curve of the west guide wall upstream or changing its geometry.

  9. 符夹铁路青龙山特大桥空间刚架设计%Design of Spatial Rigid Frame Structure of Qinglongshan Extra-long Bridge on Fujia Railway

    Institute of Scientific and Technical Information of China (English)

    侯伟

    2015-01-01

    With a view to bridge structures with small cross angle, there are many advantages of spatial rigid frame structures, such as lower construction height, high integral stiffness, less construction difficulty, convenient creation of a variety of landscape effects on side walls. Qinglongshan extra-long bridge is located in the soft soil foundation across Qingfu link railway and two underground culverts with a small oblique angle, which requires much on the space height under bridge and the foundation location. In order to achieve reasonable bridge design, the best bridge scheme is selected according basic bridge conditions, and design and calculation are conducted in perspective of spatial rigid frame with discontinuous foundation. The results show that the selected structure is reasonable and a new form of extension to the traditional rigid frame structure.%小角度交叉桥梁结构中,空间框架结构具有结构高度低、整体刚度大、施工难度小、侧墙可打造多种景观需求等优点。符夹铁路青龙山特大桥地处中软土地基,小角度斜向上跨青符铁路联络线和两个下穿涵洞,对桥下通行净空和基础位置设置有较高要求。为了合理设计大桥,根据桥梁基本情况进行桥型方案比选,并对基础间断布置的空间刚架方案进行设计计算论证。结果表明,所选结构形式合理且为传统刚架结构提供新的扩展形式。

  10. Design, development and characterization of an x-band 5 bit DMTL phase shifter using an inline MEMS bridge and MAM capacitors

    International Nuclear Information System (INIS)

    A radio frequency micro-electro-mechanical system (RF-MEMS) 5 bit phase shifter based on a distributed MEMS transmission line concept with excellent phase accuracy and good repeatability is presented in this paper. The phase shifter is built with three fixed–fixed beams; one is switchable with electrostatic actuation and the other two are fixed for a metal–air–metal (MAM) capacitor. The design is based on a coplanar waveguide (CPW) configuration using alumina substrate. Gold-based surface micromachining is used to develop the individual primary phase bits (11.25°/22.5°/45°/90°/180°), which are fundamental building blocks of the complete 5 bit phase shifter. All of the primary phase bits are cascaded together to build the complete phase shifter. Detailed design methodology and performance analysis of the unit cell phase shifter has been carried out with structural and parametric optimization using an in-line bridge and MAM capacitors. The mechanical, electrical, transient, intermodulation distortion (IMD), temperature distribution, power handling and loss performances of the MEMS bridge have been experimentally obtained and validated using simulations up to reasonable extent. A single unit cell is able to provide 31 dB return loss, maximum insertion loss of 0.085 dB and a differential phase shift of 5.95° (at 10 GHz) over the band of interest. Furthermore, all primary phase bits are individually tested to ensure overall optimum phase shifter performance. The complete 5 bit phase shifter demonstrates an average insertion loss of 4.72 dB with return loss of better than 12 dB within 8–12 GHz using periodic placement of 62 unit cells and a maximum phase error of ±3.2° has been obtained at 10 GHz. Finally, the x-band 5 bit phase shifter is compared with the present state-of-the-art. The performance of the 5 bit phase shifter when mounted inside a test jig has been experimentally investigated and the results are presented. The

  11. Design, development and characterization of an x-band 5 bit DMTL phase shifter using an inline MEMS bridge and MAM capacitors

    Science.gov (United States)

    Dey, Sukomal; Koul, Shiban K.

    2014-09-01

    A radio frequency micro-electro-mechanical system (RF-MEMS) 5 bit phase shifter based on a distributed MEMS transmission line concept with excellent phase accuracy and good repeatability is presented in this paper. The phase shifter is built with three fixed-fixed beams; one is switchable with electrostatic actuation and the other two are fixed for a metal-air-metal (MAM) capacitor. The design is based on a coplanar waveguide (CPW) configuration using alumina substrate. Gold-based surface micromachining is used to develop the individual primary phase bits (11.25°/22.5°/45°/90°/180°), which are fundamental building blocks of the complete 5 bit phase shifter. All of the primary phase bits are cascaded together to build the complete phase shifter. Detailed design methodology and performance analysis of the unit cell phase shifter has been carried out with structural and parametric optimization using an in-line bridge and MAM capacitors. The mechanical, electrical, transient, intermodulation distortion (IMD), temperature distribution, power handling and loss performances of the MEMS bridge have been experimentally obtained and validated using simulations up to reasonable extent. A single unit cell is able to provide 31 dB return loss, maximum insertion loss of 0.085 dB and a differential phase shift of 5.95° (at 10 GHz) over the band of interest. Furthermore, all primary phase bits are individually tested to ensure overall optimum phase shifter performance. The complete 5 bit phase shifter demonstrates an average insertion loss of 4.72 dB with return loss of better than 12 dB within 8-12 GHz using periodic placement of 62 unit cells and a maximum phase error of ±3.2° has been obtained at 10 GHz. Finally, the x-band 5 bit phase shifter is compared with the present state-of-the-art. The performance of the 5 bit phase shifter when mounted inside a test jig has been experimentally investigated and the results are presented. The total area of

  12. Study on Response Spectra for Design of Large Span Bridge on Ground with Thick and Soft Soil Layers%厚软场地上大跨径桥梁设计反应谱研究

    Institute of Scientific and Technical Information of China (English)

    杨伟林; 高志兵; 陶小三; 高德潜; 崔爱华

    2005-01-01

    Large span bridges have high towers and large spans with long natural-vibration cycle, and long vibration cycles of ground with thick and soft soil layers have significant effect on the bridge structures. The "Specifications of Earthquake Resistant Design for Highway Engineering of China(JTJ004-89)" can also be applied to girder bridges and arch bridges with a main span below 150 m, yet, there has been no anti-seismic design specification or guideline in China applicable to large span bridges. In this paper, the author has performed seismic response analysis for ground with thick and soft soil layer in conjunction with examples of large span bridge projects on the basis of the results of static and dynamic performance parameter in-situ tests of ground soils and dynamic triaxial test, studied the seismological effect of ground with thick and soft soil layers, discussed the design response spectrum characteristics of ground with thick and soft soil layer at different seismic intensities, and analyzed the limit of current specification of design response spectrum in actual applications. The results have important guiding significance to relevant projects, and can also be used in the promulgation of aseismic design code for large-span bridges.%大跨径桥梁塔高、跨径大、自振周期长,深厚、软弱场地的长周期地震动对桥体结构影响较大.我国也只适用主跨不超过150 m的梁桥和拱桥,国内长期以来没有一个适用于大跨径桥梁的抗震设计规范或指南.本文结合大跨径桥梁工程实例,根据场地土层静、动力性能参数的原位测试和动三轴试验结果,进行厚软场地土层地震反应分析,研究厚软场地的地震动效应,讨论了不同地震动强度时厚软场地的设计反应谱特征,分析了现行规范设计反应谱应用的局限性,成果对相关工程有重要指导意义,对大跨径桥梁抗震设计规范的制定也有借鉴作用.

  13. 新疆恰尔巴哈特桥设计流量的计算%Calculation of the Design Flow of Xinjiang QiaErBaHaTe Bridge

    Institute of Scientific and Technical Information of China (English)

    李杨; 高秋华

    2011-01-01

    Bridge design flood flow calculation in the design of the bridge site has a very important position, in order to avoid the bridge dam age , bridge design standards to ensure that flood frequency safe operation, the design process must be given to the calculation of adequate knowledge of hydrology. However, because uncertain hydrological system is a complex system of hydrological data informed of relatively limit ed. Especially in the Xinjiang Uyghur Autonomous Region, the land in the small mountain rivers, canals numerous low, and most of the hydrological record is not measured continuously, how to use the existing, adjacent to the hydrological data, inquire design flow of the basin is particularly important. Combining with the design experience of QiaErBaHaTe bridge of Highway 315, the design flow of small watershed bridge and flood design were discussed.%桥梁洪水设计流量的计算在桥位设计中有非常重要的地位,为避免桥梁水毁,保证桥梁在设计标准的洪水频率下安全运营,必须在设计过程中对水文计算给子足够的认识.但由于水文系统是一个复杂不确定的系统,水文资料的获知相对有限.尤其是在新疆维吾尔族自治区,该地中低山区小河流沟渠数不胜数,且多数没有实测连续的水文记录,如何利用现有的、邻近的水文资料,推求该流域的设计流量就尤为重要.结合参加省道315公路的恰尔巴哈特桥设计工作的经验,探讨了新疆小流域桥梁洪水设计流量的确定.

  14. The Design and Analysis of Long-Span and Low-Depth Prestressed Composite Steel-Concrete Beam Bridge

    Institute of Scientific and Technical Information of China (English)

    张俊平; 黄海云; 黄道沸

    2002-01-01

    The design scheme of long-span and low-depth composite steel-concrete beams is introduced, and the methods of avoiding the cracking of concrete deck in the negative moment regions are proposed. Moreover, significant exploration for problems of the composite beams has been made, such as optimizing construction steps to regulate the stress, applying jacking technique to exert prestress on the concrete deck, investigating the uplifting force principle of the shear connectors by means of model test and non-linear finite element analysis, and pointing out the countermeasure to reduce tension force of the shear connectors.

  15. 半桥LLC谐振变换器参数优化设计%Optimal design of parameters of half-bridge LLC resonant converter

    Institute of Scientific and Technical Information of China (English)

    钟运平; 程小华; 张勇; 程声烽

    2014-01-01

    To solve those problems such as difficulty in analyzing working principle of half-bridge LLC resonant converter,unintuitivity of parameter design, analysis of the working principle of the resonant converter was simplified based on the relationship between resonance and excitation current. Voltage gain and impedance characteristics was analyzed according to equivalent model, and the mutual relationship between the parameters was analyzed from curves of voltage gain and impedance characteristics. Parameter optimization design procedure was given. Finally a 180W/24V drive power was designed and desired simulation and experimental results were obtained.%针对半桥LLC谐振变换器工作原理分析复杂、参数设计直观性较差等问题,根据谐振电流、励磁电流的变化关系,简化了半桥LLC谐振变换器工作原理的分析。由变换器的等效电路模型分析了其电压增益、阻抗特性,并通过相应的电压增益曲线、阻抗特性曲线直观地分析了各参数间相互关系,给出了参数的优化设计步骤。最后设计了180W/24V驱动电源,仿真及实验结果均达到预期效果。

  16. Study and Design of a Dual Active Bridge Resonant Converter%一种双有源桥谐振变换器的研究与设计

    Institute of Scientific and Technical Information of China (English)

    章治国; 余海生

    2012-01-01

    A dual active bridge series resonant converter with bidirectional power flow was studied. An accurate equivalent circuit model considering effects of magnetizing inductance and leakage inductance of transformer was established to derive steady-state characteristics of the converter. Method to select optimal numerical value of magnetizing inductance was developed. Based on detailed analysis, a dual active bridge series resonant DC-DC converter operating at resonant frequency was designed. In this circuit, all switches could work in zero-voltage-switching mode for full range of loads when voltage gain is one. Meanwhile, variation of resonant voltage and current with changing loads was also investigated. Finally, as an example, an experimental circuit was constructed with SABER to demonstrate the effectiveness of theoretical analysis.%以能量双向流动双有源桥(DAB)串联谐振变换器为研究对象,在考虑隔离变压器激磁电感和泄漏电感影响的基础上,建立双有源桥串联谐振变换器的准确等效模型,推导出其稳态工作特性.分析了DAB串联谐振变换器软开关条件和激磁电感最优值选择方法.设计了一种工作在谐振频率处的DAB串联谐振DC/DC变换器,当电压增益M=1时,所有开关在全负载范围内都工作,均能实现ZVS.还分析了负载变化时谐振电压和电流的变化规律.最后给出设计实例,并用SABER仿真软件搭建了实验电路,仿真结果验证了理论分析的有效性.

  17. Myocardial bridges: morphological and functional aspects.

    OpenAIRE

    A.G. Ferreira; Trotter, S E; König, B; Décourt, L V; Fox, K; Olsen, E G

    1991-01-01

    OBJECTIVE--To assess the arrangement of myocardial bridges. DESIGN--A necropsy study of 90 consecutive hearts (56 male, 34 female). RESULTS--Myocardial bridges, either single or multiple, were seen in 50 (55.6%) of the 90 hearts. The left anterior descending artery was the most commonly affected artery. Thirty five of the 50 hearts which contained in total 41 muscle bridges were dissected further with a magnifying glass. Two different types of muscle bridges could be identified. Thirty one of...

  18. 港珠澳大桥浅水区非通航孔桥组合梁设计%Design of Composite Girders for Non-Navigable Span Bridge of Hong Kong-Zhuhai-Macau Bridge in Shallow Water Area

    Institute of Scientific and Technical Information of China (English)

    罗扣; 王东晖; 张强

    2013-01-01

    The main part of the Hong Kong-Zhuhai-Macau Bridge is a part of the combined bridge and tunnel,of which the non-navigable span bridge in the shallow water area is the 85 m span continuous composite girder bridge that totally has 64 spans of the composite girders and is 5 440 m in length.The span arrangement of the bridge mainly includes two kinds of arrangement of 6)× 85 m and 5)× 85 m.The composite girders are the separated continuous single-cell singlebox girders with constant depth and specifically are composed of the open steel box girders and the concrete deck slabs that are connected each other via shear studs.A steel box girder is the inverted trapezoid structure,a concrete deck slab is the precast full slab in the transverse direction and the grooves are pre-reserved at the locations of the shear studs.To improve the transverse mechanical behavior of the deck slabs,the stringers are set in the sections of the composite girders and to keep the integrity of the slabs,the shear studs are arranged in a way of clustering.The composite girders are erected and installed in each full span by the large transportation and erection floating crane and the girders are closed span by span.%港珠澳大桥主体工程采用桥隧组合方案,其中浅水区非通航孔桥采用85 m连续组合梁桥形式,全长5 440m,共64孔,跨径布置主要采用6×85 m和5×85m2种形式.组合梁采用单箱单室分幅等高连续梁,由开口钢箱梁和混凝土桥面板通过剪力钉联结而成.钢箱梁为倒梯形结构;混凝土桥面板为横向整块预制,在剪力钉处设置预留槽.为改善混凝土桥面板的横向受力性能,该桥组合梁截面设置小纵梁;为保持桥面板的整体性,剪力钉采用集束式布置方式.组合梁采用大型运架一体浮吊整孔安装架设,逐孔合龙.

  19. Structural Design of Multi-Pylon Cable-Stayed Bridge with Corrugated Steel Webs for Chaoyang Bridge in Nanchang%南昌朝阳大桥波形钢腹板多塔斜拉桥结构设计

    Institute of Scientific and Technical Information of China (English)

    陈水生; 钟志斌; 桂水荣; 刘旭政; 钟汉清

    2014-01-01

    The PC composite box girder with corrugated steel webs is applicable to bridges with a variety of structural types ,which exhibits superior durability and economic features as com‐pared with the common concrete box girder .The cable‐stayed bridge with corrugated steel webs is regarded as the type of structure where composite box girder with corrugated steel webs is ingen‐iously used ,making better use of the properties of the two structures . The main navigational bridge of the Chaoyang Bridge in Nanchang is a (79+ 5 × 150+79) m continuous composite box girder cable‐stayed bridge with corrugated steel webs .The bridge has six pylons and the stay ca‐bles are arranged in single cable plane .In addition ,the bridge has two layers of decks ,on the up‐per deck ,dual eight vehicle lanes (four lanes each side) are arranged and pedestrian and non‐mo‐torized vehicle lanes are arranged on the lower deck .Based on the analysis and study undertaken , small side span‐to‐main span ratio was chosen .Due to the multiple pylons ,the load path from the intermediate pylons to the side pylons is long and the effect of ancillary piers in the side spans is minimal ,as a result ,no ancillary piers are installed .In the structural system ,the pylons and the main girder are fixed while the girder and piers are separated .The box girder is 43 .84 m wide , with transverse steel diaphragms .The stay cables are fanned out in single cable plane .The pylon looks like the Chinese character“合“ ,and double bearings are installed at the pylons .T he stay vi‐bration mitigation bearings are used as the vibration mitigation and isolation devices of the super‐structure ,which are installed below the two side pylons .%波形钢腹板PC组合箱梁适用于不同结构形式的桥梁,相比普通混凝土箱梁具有显著的耐久性和经济性,波形钢腹板斜拉桥将波形钢腹板组合箱梁应用到斜拉桥中,充分发挥了2种结构的特点。南昌朝

  20. Study on structural system of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Xigang; Pei Minshan; Yuan Hong; Xu Liping; Zhu Bin

    2009-01-01

    Sutong Bridge, whose layout is [ (100 + 100 + 300) + 1 088 + ( 300 + 100 + 100) ] m, marks the largest span of cable-stayed bridges in the world. The complex natural condition at the bridge site and the strict requirements for resistance of wind and seismic action make it crucial to choose a favorable structural system to assure the function and safety of the bridge. The comparison among several optional structural systems for Sutong Bridge is illustrated. After detailed analysis is carried out for viscous damper and hydraulic buffer, super liquid viscous damper with additional displacement limitation is designed for the first application in bridge engineering. The parameters for the damper is analyzed and studied and the dampers are installed suecessfuUy after quality tests.

  1. Bridging the ';knowing and doing gap' in disaster risk reduction using design and design thinking; Ideation of concepts to improve hazard preparedness and response

    Science.gov (United States)

    van Manen, S. M.

    2013-12-01

    The central goal of disaster risk reduction (DRR) is to reduce the impact and cost of natural hazards, in human, environmental and economic terms. There are numerous approaches that aim to achieve this but recent studies have shown a substantial gap between risk reduction actions taken at national and local levels. The traditional media of the scientist: education, outreach and increasingly community involvement, have been shown to raise levels of awareness and understanding but generate little change in terms of people's actions. This can be attributed to the differences in hazard perception and the relative weight placed on various aspects by scientists, authorities and communities as a result of non-hazard related factors. Therefore DRR, particularly when placed in its social, environmental and economic contexts, is an excellent example of what is termed a ';wicked problem': a problem that is difficult to formulate, where data to base decisions on are incomplete, the stakeholders are many and they hold contradicting views and the consequences of actions on the wider system are unclear. Although both science and design are geared towards problem solving, design, in drawing equally on art and engineering skills, does so in a fundamentally different but complementary way. Neither design nor science will solve the wicked problem that is DRR, but scientists, engineers and designers can improve the current state of disaster risk reduction by tackling aspects of underlying risk factors. This work will present concepts aimed at engaging people in novel and innovative ways with scientific results, with a specific focus on improving hazard preparedness and tangible, rather than abstract, ways of communicating hazard levels. Key considerations include the need to graft onto existing behaviours or innovate on existing products to simplify implementation, the possibility to co-create and connect through design and balancing desirability with technical and economical

  2. Bridging worlds

    DEFF Research Database (Denmark)

    Rose, Jeremy; Memon, Saifullah Hassan

    2012-01-01

    (and implemented) through comparison with another university in Denmark which is well supported by computer systems. An action design research approach with an interpretative epistemology/ontology was adopted. Though the single comparison experience is difficult to generalise, we conclude that SSM...... (with some adaptations) can enable a socio-technical comparison and design effort and offer a prototype process. The comparison stimulates forward-looking design, but great care must be taken to accommodate cultural differences, and further research is necessary to integrate more sophisticated cultural...

  3. 低速风洞全模TPS试验空气桥的设计与优化%Design and optimization of the air bridge for low speed full-span TPS test

    Institute of Scientific and Technical Information of China (English)

    章荣平; 王勋年; 黄勇; 冯治

    2012-01-01

    TPS(Turbofan Powered Simulator)technology is the most advanced engine simulation in wind tunnel test. The air bridge is a key technology of TPS tests. This paper presents the design of the air bridge for low speed full-span TPS test. Optimum designs are made for the key beams of the air bridge by using FEM (finite-element method). Layout and the dimension of bellows are also optimized. According to the computation results, the key law of air bridge design is concluded. The air bridge is finally designed according to the space of the model, the inside e-quipments and the requirement of the TPS test. The final design has little effect on force measurement and has little pressure and temperature effect. The success in low speed full-span TPS test indicates that the air bridge meet the requirement of TPS test.%TPS试验技术是目前风洞试验中最先进的涡扇发动机模拟技术,空气桥是TPS试验技术的关键技术之一.介绍了低速全模TPS试验空气桥的设计.通过有限元数值模拟对空气桥关键受力梁进行了优化设计,并进一步对空气桥进行了整体优化,掌握了关键参数影响空气桥性能的规律.综合考虑模型内部空间、内部设备及空气桥的技术要求,完成了空气桥的设计,优化后空气桥对天平测力的影响较小,且同时具有较好的克服高压空气的内力、温度效应的能力.试验结果表明,空气桥性能满足TPS试验的要求.

  4. Seismic Passive Control of Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Hosam-Eddin M. Ali

    1995-01-01

    Full Text Available A three-dimensional modeling procedure is proposed for cable-stayed bridges with rubber, steel, and lead energy dissipation devices. The passive control technique is investigated by considering the response of bridge models with and without energy dissipation devices. The impact of various design parameters on the seismic response of current and future bridge designs is studied. Appropriate locations and properties of the passive devices can achieve better performance for cable-stayed bridges by balancing the significant reduction in earthquake-induced forces against tolerable displacements. Proper design of passive systems can help provide solutions for retro-fitting some existing bridges.

  5. Innovative Design and Application of Assembled Bridge Erection Machine Used for Segmental Box Girder%拼装式节段箱梁造桥机的创新设计与应用

    Institute of Scientific and Technical Information of China (English)

    张耀辉; 赵振宇; 鲍存坤

    2013-01-01

    为了解决新建兰新二线红柳河特大桥在特殊条件下的节段箱梁施工难题,在总结吸收以往造桥机施工技术的基础上,对采用八七梁杆件为主要材料的拼装式造桥机进行了大胆的创新设计.特殊设计了不同以往造桥机的前、中、后支腿等特殊支撑结构,并采用了独特的造桥机过孔模式和安全保护措施,很好地实现了特殊条件下的高速铁路箱梁节段拼装施工要求,供其他类似工程的施工参考借鉴.%To solve the construction problems in segmental box girder of Hongliu River Bridge on the new second line of Lanzhou - Xinjiang Railway under the special conditions, this assembled bridge erection machine, which was mainly composed of the 87-type railway emergency steel beams, was designed boldly with technical innovation based on the construction technologies of former bridge erection machines. For this machine, some special supporting structures were designed, such as the front leg, middle leg and the rear leg, which were different from the previous similar machines. In addition, the unique models were adopted for this machine passing through the bridge spans and for the security measures, so that it can meet the requirements of segmental method for box girder of high-speed railway under the special condition, and can also provide good reference for the bridge erection of similar projects.

  6. 大连星海湾跨海大桥主桥总体设计%Overall Design of Main Bridge of Xinghai Bay Sea-Crossing Bridge in Dalian

    Institute of Scientific and Technical Information of China (English)

    檀永刚; 陈亮; 张哲

    2015-01-01

    大连星海湾跨海大桥主桥为(180+460+180) m双层地锚式悬索桥,主梁为钢桁架结构形式,采用整体节点构造,上、下2层桥面板均采用正交异性钢桥面板,桥面上铺装5.5 cm厚双层环氧沥青。锚碇采用空腹三角形框架混凝土重力式锚碇,设置在水深20~30 m的海床上,锚碇基础采用整体大沉箱,单个沉箱重达26000 t ,在船坞内预制完成后用拖轮拖运到桥位处安装在碎石基床上,碎石基床采用升浆技术进行加固。桥塔采用钢筋混凝土框架结构,设上、下2道横梁。主缆由钢丝强度等级为1770 M Pa的平行钢丝索股组成,并用长达16 m的刚性拉杆锚固在锚碇上,同时采用除湿系统结合传统防腐涂装体系的结构进行防腐,以提高缆索系统的耐久性。%T he main bridge of Xinghai Bay Bridge in Dalian is a double‐deck earth‐anchored sus‐pension bridge with span arrangement of (180+ 460+ 180) m .The stiffening girder adopts the type of steel truss girder structure with integrated nodes .The upper and lower bridge decks are fitted with orthotropic steel plate deck paved with 5 .5 cm thick double‐layer epoxy asphalt .The anchorages are the concrete gravity anchor blocks with open‐web triangular framework ,sitting on the seabed that is 20~30 m under the sea ,the foundations of w hich adopt the large integrated cais‐sons ,each weighing up to 26 000 t .The caissons were prefabricated in the ship yard ,and then towed to the bridge site by the tug boats ,and sunk to the crushed stone seabed that are strength‐ened by prepackaged aggregate concrete technology .Bridge towers are the reinforced concrete frame structures ,equipped with an upper and a lower cross beams .The main cables are made up of prefabricated parallel wire strands ,each with a strength of 1 770 MPa ,anchored to the anchor blocks using the 16 m long rigid anchoring roads .T he main cables are corrosion

  7. Architectural engineering of FRP bridges

    OpenAIRE

    Smits, J.E.P.

    2014-01-01

    This paper deals with the use of Fibre Reinforced Polymers (FRP's) in architectural and structural bridge design. The challenges and opportunities that come with this relatively new material are discussed. An inventory is made of recent engineers' solutions in FRP, followed by a discussion on architectural application of FRP's derived from the authors architectural practice.

  8. Bridge Aesthetics and Structural Honesty

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    In bridges the overall form must be chosen with due respect to the transmission of forces if efficient structures shall be created, The design must therefore be governed by experienced structural engineers - in some cases assisted by aesthetic advisers on specific issues. Some basic requirements...

  9. Architectural engineering of FRP bridges

    NARCIS (Netherlands)

    Smits, J.E.P.

    2014-01-01

    This paper deals with the use of Fibre Reinforced Polymers (FRP's) in architectural and structural bridge design. The challenges and opportunities that come with this relatively new material are discussed. An inventory is made of recent engineers' solutions in FRP, followed by a discussion on archit

  10. 道路桥梁设计中的隐患及解决措施分析%Analysis on Hidden Troubles and Solutions in the Design of Roads and Bridges

    Institute of Scientific and Technical Information of China (English)

    石磊

    2014-01-01

    道路桥梁是人们日常生活中必备的交通基础设施,其设计的科学与否直接影响着其使用寿命、交通质量,甚至关系到人们的生命安全。本文分析了道路桥梁设计中存在的隐患问题,并探究了具体解决的策略。%Roads and Bridges are the necessary infrastructure facilities in people's Daily life, its design is scientific or not affects the quality of its service life and affects the quality of its transportation directly, even is related to people's safety. The hidden troubles in the design of roads and bridges are analyzed in this paper, and the concrete solutions are also explored.

  11. 基于性能的中小跨径装配式梁桥地震易损性分析%Fragility analysis for performance-based seismic design of prefabricated bridge with middle-small span

    Institute of Scientific and Technical Information of China (English)

    张云; 谭平; 郑建勋; 周福霖

    2014-01-01

    标准跨径装配式梁桥由于造价低廉,便于设计和施工,在中国公路路网中广泛使用,成为公路网应用最多的桥型结构。虽然使用广泛,但是针对具有这种设计特点桥梁的地震易损性的研究还比较少。本文以典型的多跨梁桥为例,以使用功能作为设防目标定义了桥梁的5种性能水平,提出了详细的桥墩损伤指标界定值作为桥墩4种损伤极限状态界定准则。在此基础上,明确提出了这类桥梁的地震易损性分析方法,考虑了结构本身主要材料的不确定性和地震动输入的不确定性,得到了结构的地震易损性曲线。根据易损性分析结果,探讨了桥梁失效模式和损伤概率,为公路路网抗震能力分析和应急预案的制定提供了理论依据。%The prefabricated bridge with standard span have become the most widely used structure in the highway-net by ad-vantage of its low cost ,simple design and construction .However ,study on seismic fragility of such bridges is rarely found yet .Taking service function as seismic fortification goal ,this paper defines five levels of performance for typical multi-span bridges .The critical damage value for the bridge pier is put forward as the criteria of four kinds of pier damage limit states . Moreover ,the method and procedure of seismic fragility analysis of highway bridges are presented ,in which uncertainties of the primary structure materials and ground motion input are considered respectively .The seismic fragility analysis is conducted to obtain the bridge failure mode and damage probability .The fragility analysis for performance-based seismic design of high-way bridges provides the theoretical basis for a seismic performance analysis and emergency preplan formulation in the high-w ay-net .

  12. The Design for a 132 m Double Track Simply Supported Steel Truss Beam of Guchengwan Main Bridge%古城湾特大桥主桥1孔132m双线铁路钢桁梁设计

    Institute of Scientific and Technical Information of China (English)

    吴文华

    2015-01-01

    as late maintenance and replacement for the integral ballast trough plate.(2)The possibility of using simple supported structure could prevent the waste of using side span. (3)A reasonable plate thickness,design composition,weld distribution,stress control,and all of these methods could solve the problems about brittleness break of steel bridge under low temperate.(4)The main bridge employs parallel rotation with no balance weight construction schemes,which reduces the impact of the construction on the existing railway transport greatly.(5 )The structure design,new bridge deck system and creative construction scheme in this bridge,may give clues on the same bridge 's design and construction in the future.

  13. Design of Half-through Anomalistic Arch Bridge on Changsha-Kunming Passenger-dedicated Line%长昆客运专线铁路中承式异型拱桥设计研究

    Institute of Scientific and Technical Information of China (English)

    施威; 孙大斌

    2015-01-01

    为解决长昆客运专线斜跨潭韶高速公路的问题,通过桥式方案比选,结构构造优化,结构静力、动力计算分析,设计研究出拱肋沿桥轴线非对称错位布置、吊杆扇形布设、无风撑拱肋的中承式斜置拱桥。该桥已投入实际运营,应用良好。%To resolve the problem in design to allow Changsha-Kunming passenger dedicated railway to cross over Xiangtan-Shaoshan highway, this paper, on the basis of bridge scheme comparison, construction structure optimization, calculation and analysis of structural statistics and dynamics, comes to the conclusion that the half-through anomalistic arch bridge is recommended and arranged unsymmetrically and misplaced with its arch ribs along the bridge axial line, with its suspenders placed in fan-shape and its arch ribs without wind bracing. This bridge has been put into use with good results.

  14. Output filter design of half bridge chopping inverter%半桥斩波逆变器输出滤波器设计

    Institute of Scientific and Technical Information of China (English)

    李永; 张承瑞; 翟鹏; 胡天亮; 林明星

    2012-01-01

    For the half-bridge inverter based on sinusoidal pulse width modulation (SPWM) , its output voltage contains a large amount of high-order harmonic which will bring vibration, noise and damage to the actuator. An LCCR filter applied to the inductive load was proposed based on analyzing the shortcomings of the LC filter with inductive load. It was difficult to design the parameters of this high order low-pass filter. A design method of parameters computed was presented based on comparing the difference of transfer characteristics between second-order LC filter and high-order LCCR filter and analyzing the different impact of each component to the filter. The simulation and experimental results show that the LCCR filter has good performance to applying the occasions of high power, and its active power loss was low and resonant suppression is good. The results indicate that the filter designed with this method has good performance.%针对正弦波脉冲宽度调制(SPWM)的半桥斩波逆变器输出的电压中含有大量的高次谐波会给致动器带来振动、噪声及对致动器线圈绕组绝缘造成破坏等问题,分析了带感性负载条件下的LC滤波器存在的不足,提出将带阻尼的LCCR滤波器应用于感性负载的方案.针对这种高阶低通滤波器各参数设计困难的问题,通过比较二阶LC滤波器和高阶LCCR滤波器的传递特性,分析滤波器中各元件对滤波器特性的影响,在此基础上提出带感性负载的LCCR滤波器参数设计的方案.通过仿真及试验验证带阻尼的LCCR滤波器的性能,试验结果表明:该滤波器有功损耗低,谐振抑制性好,适用应于高电压、大功率的场合.

  15. A data management infrastructure for bridge monitoring

    Science.gov (United States)

    Jeong, Seongwoon; Byun, Jaewook; Kim, Daeyoung; Sohn, Hoon; Bae, In Hwan; Law, Kincho H.

    2015-04-01

    This paper discusses a data management infrastructure framework for bridge monitoring applications. As sensor technologies mature and become economically affordable, their deployment for bridge monitoring will continue to grow. Data management becomes a critical issue not only for storing the sensor data but also for integrating with the bridge model to support other functions, such as management, maintenance and inspection. The focus of this study is on the effective data management of bridge information and sensor data, which is crucial to structural health monitoring and life cycle management of bridge structures. We review the state-of-the-art of bridge information modeling and sensor data management, and propose a data management framework for bridge monitoring based on NoSQL database technologies that have been shown useful in handling high volume, time-series data and to flexibly deal with unstructured data schema. Specifically, Apache Cassandra and Mongo DB are deployed for the prototype implementation of the framework. This paper describes the database design for an XML-based Bridge Information Modeling (BrIM) schema, and the representation of sensor data using Sensor Model Language (SensorML). The proposed prototype data management framework is validated using data collected from the Yeongjong Bridge in Incheon, Korea.

  16. State-of-the-art of long-span bridge engineering in China

    Institute of Scientific and Technical Information of China (English)

    XIANG Haifan; GE Yaojun

    2007-01-01

    This paper introduces the state-of-the-art of long-span bridge engineering in China with emphases on recent long-span bridge projects,bridge deck configuration and material,design codes of long-span bridges and improvement of aerodynamic performance.The recent long-span bridge projects include thirty-eight completed suspension bridges,cable-stayed and arch bridges with a main span over 400 m,and eighteen major bridges are under construction.The bridge deck configuration and material,with prestressed concrete decks,steel-concrete composite decks and steel box decks together with several popular cross-sections,are presented.The third part briefly outlines four design codes,including static and dynamic design for highway long-span bridges,and the recent engineering experiences gained from several aerodynamic vibration control projects of long-span bridges are shared in the last part.

  17. 矮墩桥梁的抗震设计与计算%Seismic Design and Calculation of Short Pier Bridge

    Institute of Scientific and Technical Information of China (English)

    宿其连

    2014-01-01

    以3×30m连续梁桥为例,在桥墩高度为5m时,建立该桥的三维有限元模型。桥梁主梁和桥墩通过弹性连接来模拟桥梁支座,考虑土和桩基的相互作用,通过土弹簧来模拟,并在桥梁横向和纵向两个方向输入地震作用。采用反应谱法进行分析。%This is a study on the building of the three-dimensional finiteelement model. It takes the continuous beam bridge which is 3í30m in length and 5m in height as an example. The bridge bearings are supposed to be constructed by elastic connect-ion of the bridge girder and pier. To take the bridge as a whole, the interaction between soil and pile foundation should be put into consideration. Soil spring is used to simulate the model, and the seismic effect is input in horizontal and vertical direction of the bridge. The data are analyzed by response spectrum method.

  18. 胶合木桥的设计、制备及其结构性能试验研究%Design, Fabrication and Experimental Study on Structural Behaviors of Glulam Bridges

    Institute of Scientific and Technical Information of China (English)

    杨会峰; 陆伟东; 岳孔; 王伟

    2011-01-01

    The design method, fabrication and the structural behavior of glued laminated timber (glulam) bridges were presented in this paper. It was firstly given the design scheme, such as design conditions, specifications, material properties and structural solution. Based on this, by using FEM software MIDAS/Gen, the structural behavior of the glulam bridge was analyzed, in which the mainly working condition includes full - span live load, half - span live load and human - induced vibration. Analytical results indicate that the stress level and structural stiffness met the requirements of load carrying ability and normal use. Then the processing technique of glulam and installation of glulam bridge were introduced briefly. Furthermore, nondestructive testing with a stacked load has been carried out to study the structural behaviors of the bridge. The experimental results were in good consistency with the analytical results from FEM software.%在做出设计方案,包括技术条件、设计规范、材料参数及桥梁选型等的基础上,利用通用有限元软件MIDAS/Gen对木桥进行了结构分析,主要的计算工况包括全跨活荷载、半跨活荷载及人致振动等。分析结果表明,该桥的应力水平及结构刚度等均满足承载能力及正常使用要求。同时简要介绍了胶合木加工工艺及木桥的装配过程,并且通过静力堆我试验对整桥进行了结构性能测试,试验结果与有限元分析结果吻合较好。

  19. The Reinforcement and Reconstruction Design of a Hollow Type Arch Bridge%某空腹式拱桥加固改造设计

    Institute of Scientific and Technical Information of China (English)

    聂立力

    2014-01-01

    拱桥最为我国最常用的一种桥梁形式,其使用时间较长时容易出现病害。本文以一山区空腹式拱桥为例,对其病害情况、加固措施及施工要点等进行了分析与研究,希望能为相关工程提供借鉴。%Arch bridge is the most commonly used bridge form in China, which can easily cause diseases when use for a long time. This article takes a hol ow type arch bridge in a mountain as an example and carries on the analysis and study of the disease situation, the reinforcement measures, and the main points of construction, and hope to provide reference for related projects.

  20. Halliburton Composite Bridge Plug Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Starbuck, J.M.; Luttrell, C.R.; Aramayo, G.

    2005-01-15

    The overall objectives of this CRADA were to assist Halliburton in analyzing a composite bridge plug and to determine why their original design was failing in the field. In Phase 1, finite element analyses were done on the original composite slip design and several alternative designs. The composite slip was the component in the bridge plug that was failing. The finite element code ABAQUS was used for these calculations and I-DEAS was used as the pre- and post-processor in the analyses. Several different designs and materials were analyzed and recommendations were made towards improving the design. In Phase 2, the objective was to develop finite element models that would accurately represent the deformations in the entire all-composite 4-1/2' diameter bridge plug assembly. The finite element code LS-DYNA was used and the results from this effort were intended to expand Halliburton's composite design and analysis capabilities with regard to developing future composite components for downhole tools. In addition to the finite element modeling, this effort involved the utilization of micromechanics to determine the necessary composite material properties that were needed as input for finite element codes.

  1. 基于两水平设防的连续梁桥抗震性能分析%Seismic Performance Analysis of Continuous Girder Bridge Based on Two-level Design Approach

    Institute of Scientific and Technical Information of China (English)

    邓小伟

    2012-01-01

    According to the new ideas and new methods by guidelines for seismic design of highway bridges (JTG / T B02-01-2008) , with the background of a continuous girder bridge in the area of 7 degree earthquake intensity, an elastic-plastic finite element model is established for dynamic characteristics analysis, seismic response spectrum analysis and nonlinear time history analysis, to reveal the force and deformation under earthquake action of two levels. Furthermore, the seismic performance is evaluated to provide a reference for seismic design of bridges.%根据《公路桥梁抗震设计细则》(JTG/T B02—01—2008)中的抗震设防新理念和新方法,以Ⅶ度区某连续梁桥为工程背景,建立了弹塑性有限元模型,依次进行了动力特性分析、地震反应谱分析和非线性时程分析,揭示了两级地震作用下桥梁的受力及变形情况,并对桥梁的抗震性能进行了评价,可供桥梁抗震设计参考.

  2. 双塔双索面支座体系混合式结合梁斜拉桥设计%Design of Double Pylons and Cable Plane Supporting System Hybrid Composite Girder Cable-stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    谢波; 程应刚

    2014-01-01

    以洸府河大桥为工程背景,进行了双塔双索面支座体系混合式结合梁斜拉桥的平面、纵断面和横断面设计,介绍了主桥的桥跨布置、桥梁方案,同时进行了中跨结合梁钢主梁、中跨结合梁混凝土桥面板、边跨混凝土主梁、主梁钢-混结合段、斜拉索、主塔和基础的设计,并进行了结构计算。%The plane,longitudinal section and cross section design of double pylons and cable plane supporting system hybrid composite girder cable-stayed bridge was carried out on the background of Guang Fuhe bridge.This paper introduced the bridge span arrangement and scheme,and conducted the design and structure calculation of steel girder in composite girder at midspan,concrete deck in composite girder at midspan,concrete main girder at side span ,steel-concrete mixing section,cable, tower and foundation.

  3. Seismic Design of Bridge with Vibration Isolation Device under the Action of E2 Earthquake Load%E2地震作用下减隔振桥梁的抗震设计

    Institute of Scientific and Technical Information of China (English)

    禚一; 王菲

    2013-01-01

    Taking a bridge with vibration isolation device as an example, the 3D finite element model which considered the influence of pile-soil interaction was established. And then according to the material characteristic of concrete and steel bar, the proper dynamic elastic-plastic constitutive models were selected and the elastic - plastic spherical steel bearings with the function of seismic isolation were also simulated. Furthermore, by using three artificial seismic time-history waves, the elastic-plastic time-history analysis on this bridge under the action of E2 earthquake load was carried out to calculate the strength and deformation of this bridge. The results of detailed calculation and analysis prove that the bridge in this paper is designed safely and reliably. Also, the design for this bridge provides a reference for irregular bridge's seismic analysis under the action of E2 earthquake load.%以某减隔振桥梁为例,建立该桥的三维有限元模型,考虑桩-土相互作用的影响,并根据混凝土和钢筋的材料特性,选取适宜的动力弹塑性本构模型,同时模拟了弹塑性减隔振球型钢支座,并采用人工拟合的3条地震动时程曲线对该桥进行了E2地震作用下的弹塑性时程分析,验算该桥在E2地震作用下的强度及变形.经过详细的验算与分析,验证了本桥设计的安全性和可靠性,并为实际工程中的非规则桥梁在E2地震作用下的抗震验算提供参考依据.

  4. Design of Steel-Concrete Composite Continuous Rigid Frame Bridge on Changping Light Railway%昌平轻轨钢-混凝土结合连续刚构桥设计

    Institute of Scientific and Technical Information of China (English)

    王冰

    2014-01-01

    Consisting of two multi-span units of ( 37+60+79+42.5 )-m and ( 42.5+79+42.5 )-m, a steel-concrete composite continuous rigid frame was used for the viaduct bridge on Changping line of Beijing urban rail transit to cross above existing railway lines. The bridge is characterized by large bridge span, small curve radius, high earthquake intensity, many existing railway lines under the bridge, etc.;and so the design for it was dominated by many factors. This paper introduced the scheme selection, structure design, calculation of effective width of main girder, and the treatment of the rigid connection zone between piers and girder. And then in order to solve the stress problem in concrete bridge deck in the negative bending moment zone of the continuous girder, a variety of treatment methods were proposed in this paper, such as using prefabricated bridge deck, static pre-loading, longitudinal pre-stressing, hysteresis effect, high reinforcement ratio and so on. Furthermore, the effects of treatment measures were comprehensively compared with each other in this paper so as to determine the final construction scheme.%轨道交通昌平线高架区间跨线桥采用两联桥跨布置为(37+60+79+42.5) m及(42.5+79+42.5) m的钢-混凝土结合连续刚构方案,本桥具有跨度大、曲线半径小、地震烈度高、桥下既有线众多等特点,设计控制因素较多。介绍该桥的方案选择、结构设计、主梁有效宽度计算以及墩梁固结段的处理,并针对连续梁负弯矩区混凝土桥面板受力问题,提出预制桥面板、预加静载法、施加纵向预应力、滞后结合、高配筋率等多种处理方法,对其效果做出综合比较,以确定最终施工方案。

  5. Analysis and design of a parallel-connected single active bridge DC-DC converter for high-power wind farm applications

    DEFF Research Database (Denmark)

    Park, Kiwoo; Chen, Zhe

    2013-01-01

    This paper presents a parallel-connected Single Active Bridge (SAB) dc-dc converter for high-power applications. Paralleling lower-power converters can lower the current rating of each modular converter and interleaving the outputs can significantly reduce the magnitudes of input and output current...

  6. Foot force models of crowd dynamics on a wobbly bridge

    CERN Document Server

    Belykh, Igor; Belykh, Vladamir

    2016-01-01

    Modern pedestrian and suspension bridges are designed using industry-standard packages, yet disastrous resonant vibrations are observed, necessitating multi-million dollar repairs. Recent examples include pedestrian induced vibrations during the openings of the Solf\\'erino Bridge in Paris in 1999 and the increased bouncing of the Squibb Park Bridge in Brooklyn in 2014. The most prominent example of an unstable lively bridge is the London Millennium Bridge which started wobbling as a result of pedestrian-bridge interactions. Pedestrian phase-locking due to footstep phase adjustment, is suspected to be the main cause of its large lateral vibrations; however, its role in the initiation of wobbling was debated. In this paper, we develop foot force models of pedestrians' response to bridge motion and detailed, yet analytically tractable models of crowd phase-locking. We use bio-mechanically inspired models of crowd lateral movement to investigate to what degree pedestrian synchrony must be present for a bridge to ...

  7. Violin bridge mobility analysis under in-plane excitation.

    Science.gov (United States)

    Zhang, Cheng-Zhong; Zhang, Guang-Ming; Ye, Bang-Yan; Liang, Li-Dong

    2013-11-08

    The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2-3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility.

  8. Violin Bridge Mobility Analysis under In-Plane Excitation

    Directory of Open Access Journals (Sweden)

    Cheng-Zhong Zhang

    2013-11-01

    Full Text Available The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2–3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility.

  9. Design of Curve Cable-Stayed Bridge with Steel-Box Hybrid Girder for Four-Track Railway%四线铁路钢箱混合梁弯斜拉桥设计研究

    Institute of Scientific and Technical Information of China (English)

    罗世东; 饶少臣

    2011-01-01

    According to the mechanical characteristics of the curve cable-stayed bridge of four-track railway, the structure design and research on the cable, girder, bridge towers and foundation construction were launched by space bar finite element static analysis method in terms of the cable-stayed bridge architecture, the bridge stiffness, shrinkage and creep, and geometric nonlinearity etc. FEM analysis was used to study the stress distribution of the orthotropic steel box decks under the combined effect of the vertical and horizontal bending, shear lag and torsion warping. With FEM simulation, the local stress analysis and structure research were carried out on several aspects, such as the joint section of steel box girder and the prestressed concrete beam, the consolidation area between the main girder and the crossbeam of the bridge tower as well as the upper and lower steel anchor boxes for stay cable. Vehicle-bridge coupled time-varying analysis method was adopted to study the train running dynamic performance. Response spectrum method and seismic time history analysis method were used to study and analyze the seismic performance and seismic measures of the structure. Analyses show that about 3 m distance between the diaphragm and the web plates adopted for the steel box girder plays important role in improving the main beam structure in the curve cable-stayed bridge of four-track railway. Good train operation performance indicates that 1/900 deflection-span ratio adopted for the bridge to control the structural stiffness is more reasonable. E-type steel damping bearing has improved the seismic performance of the bridge.%根据四线铁路弯斜拉桥的受力特点,采用空间杆系有限元静力分析方法,围绕斜拉桥结构体系、桥梁整体刚度、收缩徐变、几何非线性等方面对其展开拉索、主梁、桥塔、基础的构造设计与研究.采用有限元仿真分析技术,研究正交异性桥面板的弯钢箱梁在受纵横向弯曲

  10. Live-Load Testing and Finite-Element Analysis of a Steel Cantilever Deck Arched Pratt Truss Bridge for the Long-Term Bridge Performance Program

    OpenAIRE

    Laurendeau, Matthew P.

    2011-01-01

    The Long Term Bridge Performance (LTBP) program is an organization within the Federal Highway Administration that inspects, tests, analyzes, and observes, for an extended period of time, a variety of bridge types throughout the United States. Part of the program includes periodic testing of select bridges of a span of 20 years. The Kettle River Bridge located outside of Sandstone, Minnesota was selected for study due to its unique design. The Kettle River Bridge is a historical steel can...

  11. Design of fully enclosed acoustic barrier of Yangze River Bridge in Yingwu continent of Wuhan city%武汉市鹦鹉洲长江大桥全封闭声屏障设计

    Institute of Scientific and Technical Information of China (English)

    李明华

    2016-01-01

    根据声屏障声学原理,从建筑景观设计、结构设计、辅助设计等方面,探讨了武汉市鹦鹉洲长江大桥全封闭声屏障设计方法,并介绍了声屏障施工与维护措施,有效解决了高架道路交通噪声问题。%According to acoustical principle of acoustic barrier,starting from aspects of building landscape design,structural design and aided design,the paper explores design methods of fully enclosed acoustic barrier of Yangze River Bridge in Yingwu continent of Wuhan city,and intro-duces acoustic barrier construction and maintenance measures,which effectively solves elevated road traffic noise problem.

  12. Application of Long-span Bridges Structure in the Design of Heavy Cargo Wharf%大跨度桥型结构在重件码头设计中的应用研究

    Institute of Scientific and Technical Information of China (English)

    罗家安; 黄亚栋; 张鹏飞; 张跃博

    2016-01-01

    The subject of the article is the bearing-trail beam used in a heavy cargo wharf in Wuhan. The cantilever length of the bearing-trail beam is 28 meters, the span of the bridge crane is 52 meters, and the lifting capacity of the bridge crane is 500 tons. For the special requirements of the long cantilever, long span and large lifting capacity, the suspension beam structure is researched using the theory of the long-span bridge type structure. The advantages and disadvantages of different bridge structure applied in the project are analyzed by the finite element analysis software of ANSYS. The research results could provide a theoretical foundation for the design of the heavy cargo wharf.%本文以武汉某重件码头工程吊车梁结构作为研究对象,该码头吊车梁结构悬臂段长度为28 m,桥式起重机跨度为52 m,最大起重量达到500 t,针对这一悬臂长、跨度大和起重量大的特殊使用要求,在本次设计中借鉴引用了大跨度桥型结构对该伸臂梁结构进行研究,使用有限元软件ANSYS分析不同桥型结构在该项目中应用的优缺点,研究成果可为该类型的重件码头设计提供理论参考。

  13. GFRP-花旗松胶合木夹芯桥面板受弯性能试验与结构设计%Experiment on Bending Capacity and Structural Design of GFRP-pseudotsuga Taxifolia Glulam Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    方海; 韩娟; 刘伟庆; 祝露

    2014-01-01

    采用花旗松胶合木作为芯材,玻璃纤维增强复合材料(GFRP)作为面层制备夹芯结构桥面板,在对花旗松胶合木芯材和 GFRP 开展基本力学性能试验研究的基础上,开展了 GFRP-花旗松胶合木夹芯梁的受弯性能试验,得出了其荷载-跨中挠度曲线与 GFRP 荷载-跨中应变曲线,并对抗弯刚度测试值与理论计算值进行了对比;针对某 GFRP-花旗松胶合木桥面板,提出了完整的结构设计流程,给出了桥面板的合理设计参数。研究结果表明:GFRP-花旗松胶合木桥面板应用于钢梁-复合材料桥面板组合桥梁结构较为可行。%The bridge panel of sandwich structure was manufactured by using pseudotsuga taxifolia glulam as core materials and glass fiber reinforced polymer (GFRP) as surface course . The bending experiment of GFRP-pseudotsuga taxifolia glulam beam was carried out based on basic mechanical property of pseudotsuga taxifolia glulam core materials and GFRP .From the bending experiment ,the load-midspan deflection curve and GFRP load-midspan strain curve were got ,and the test value was compared with theoretical value of bending stiffness .It brought up a whole structured design process of a sandwich structure bridge deck , and gave the design parameter of bridge deck .The study results show that using GFRP-pseudotsuga taxifolia glulam bridge deck into girder-composite bridge panel is feasible .

  14. GFRP-花旗松胶合木夹芯桥面板受弯性能试验与结构设计%Experiment on Bending Capacity and Structural Design of GFRP-pseudotsuga Taxifolia Glulam Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    方海; 韩娟; 刘伟庆; 祝露

    2014-01-01

    The bridge panel of sandwich structure was manufactured by using pseudotsuga taxifolia glulam as core materials and glass fiber reinforced polymer (GFRP) as surface course . The bending experiment of GFRP-pseudotsuga taxifolia glulam beam was carried out based on basic mechanical property of pseudotsuga taxifolia glulam core materials and GFRP .From the bending experiment ,the load-midspan deflection curve and GFRP load-midspan strain curve were got ,and the test value was compared with theoretical value of bending stiffness .It brought up a whole structured design process of a sandwich structure bridge deck , and gave the design parameter of bridge deck .The study results show that using GFRP-pseudotsuga taxifolia glulam bridge deck into girder-composite bridge panel is feasible .%采用花旗松胶合木作为芯材,玻璃纤维增强复合材料(GFRP)作为面层制备夹芯结构桥面板,在对花旗松胶合木芯材和 GFRP 开展基本力学性能试验研究的基础上,开展了 GFRP-花旗松胶合木夹芯梁的受弯性能试验,得出了其荷载-跨中挠度曲线与 GFRP 荷载-跨中应变曲线,并对抗弯刚度测试值与理论计算值进行了对比;针对某 GFRP-花旗松胶合木桥面板,提出了完整的结构设计流程,给出了桥面板的合理设计参数。研究结果表明:GFRP-花旗松胶合木桥面板应用于钢梁-复合材料桥面板组合桥梁结构较为可行。

  15. PARAMETRIC STUDY OF SKEW ANGLE ON BOX GIRDER BRIDGE DECK

    OpenAIRE

    Shrikant D. Bobade *, Dr. Valsson Varghese

    2016-01-01

    Box girder bridge deck, is the most common type of bridges in world and India, it consists of several Slab or girders. The span in the direction of the roadway and connected across their tops and bottoms by a thin continuous structural stab, the longitudinal box girders can be made of steel or concrete. The Simple supported single span concrete bridge deck is presented in present study. Skewed bridges are suitable in highway design when the geometry of straight bridges is not possible. The sk...

  16. Ambient Modal Testing of the Vestvej Bridge using Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Brincker, Rune; Rytter, A.

    This paper presents an ambient vibration study of the Vestvej Bridge. The bridge is a typically Danish two-span concrete bridge which crosses a highway. The purpose of the study is to perform a pre-investigation of the dynamic behavior to obtain information for the design of a demonstration project...... concerning application of vibration based inspection of bridges. The data analysis process of ambient vribration testing of bridges has traditionally been based on auto and cross spectral densities estimated using an FFT algorithm. In the pre-analysis state the spectral densities are all averaged to obtain...

  17. Ambient Modal Testing of the Vestvej Bridge using Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Brincker, Rune; Rytter, A.

    1998-01-01

    This paper presents an ambient vibration study of the Vestvej Bridge. The bridge is a typically Danish two-span concrete bridge which crosses a highway. The purpose of the study is to perform a pre-investigation of the dynamic behavior to obtain information for the design of a demonstration project...... concerning application of vibration based inspection of bridges. The data analysis process of ambient vribration testing of bridges has traditionally been based on auto and cross spectral densities estimated using an FFT algorithm. In the pre-analysis state the spectral densities are all averaged to obtain...

  18. Annex 3: BRIDGESIM, a simulation tool for the system design of bridge heating for ice prevention with solar heat stored in a seasonal ground duct store

    Energy Technology Data Exchange (ETDEWEB)

    Pahud, D.

    2006-12-15

    This is the Annex 3 of the annual report 2006 of the Serso project. This appendix provides details on the BRIDGESIM simulation tool for the simulation of a bridge heating system that uses heat stored in summer in a long-term diffusive borehole store to ensure an ice-free surface on a road bridge in winter. The operation of the control system which controls the heating system is described. The simulation tool is described and the various input parameters are discussed, as is the parametrisation of the tool itself. These parameters include not only timescales but also data on the borehole heat exchangers, data on the buried heating pipes in the road surface, thermal conductivity of the circulating heat-transfer fluid, ground parameters, intermediate water tank parameters and many other related data. The running of the simulation and output data are also described. Outputs are also presented in graphical form.

  19. Inspection Strategies for Concrete Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    1989-01-01

    In this paper an optimal inspection strategy for concrete bridges based on periodic routine and detailed inspections is presented. The failure mode considered is corrosion of the reinforcement due to chlorides. A simple modelling of the corrosion and of the inspection strategy is presented....... The optimal inspection strategy is determined from an optimization problem, where the design variables are time intervals between detailed inspections and the concrete cover. The strategy is illustrated on a simple structure, namely a reinforced concrete beam....

  20. Concrete bridge prioritization system

    OpenAIRE

    Kesselring, Debbie Anne

    1995-01-01

    An alternative method of prioritization for concrete bridge maintenance, repair, and rehabilitation activities is required due to the inability of the current system to manage the increasing nmnber of aging concrete bridges. The Concrete Bridge Prioritization System was proposed because of its ability to address the critical technical parameters of safety and cost benefit in prioritization of funding and work allocation. The analysis includes four parts, service life assessment, s...

  1. 厦门新阳大桥耐久性混凝土配合比设计与生产%Mix Proportion Design and Production of Durable Concrete in Xiamen New Yang Bridge

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    该文以厦门新阳大桥马銮湾海堤开口改造为例,阐述了耐久性混凝土的配合比设计与生产工艺,为改善工程质量提高混凝土耐久性、抗腐蚀性提供了参考。%Taking Maluan Bay Seawall Opening in Xiamen New Yang Bridge as an example,this article introduced mix proportion design and production of durable concrete,and gave some advice for improving engineering quality and concrete durability.

  2. Application Design of LLC Resonant Full-Bridge Converter Based on Digital Control%数字控制LLC谐振全桥变换器的应用设计

    Institute of Scientific and Technical Information of China (English)

    史永胜; 李晓明; 高丹阳

    2016-01-01

    In order to improve the efficiency of analog switching power supply,the design of digital power based on DSP is proposed. This paper analyzes the theory of LLC resonant converter that takes the full-bridge as the main circuit. A program for the full-bridge converter based on DSP TMS320F28335 is introduced. Finally a prototype of 300 V~400 V input ,48 V/12 A output was fabricated and tested. Saber software has been used to simulate and debug the full-bridge LLC resonate convertes in the design proceeding. The design of digital control and software system are given. ZCS and ZVS can be maintained in full load. The output ripple is less than 0.5%,efficiency is more than 95%,both of them achieve the design requirements.The result proved that the Full-bridge LLC resonant converter confirms the development trend of the power supply with the higher power density and efficiency.%针对模拟电源效率较低的现状,提出一种基于DSP的数字电源方案。在对LLC谐振全桥变换器工作原理简单分析的基础上,采用DSP TMS320F28335设计了一款输入为DC 300 V~400 V,输出为DC 48 V/12 A的原理样机。利用Saber仿真软件对其进行仿真与调试,仿真结果与实验数据表明,本文设计的LLC全桥谐振变换器能够在全负载范围内实现初级零电压开通(ZCS)以及次级零电流关断(ZVS),输出电压纹波小于±0.5%,效率达到95%以上,满足设计要求。结论表明,LLC谐振变换器符合电源高功率密度、高效率的发展要求。

  3. Analysis of Anti-Seismic Design of Long-Span Continuous Rigid-Frame Railway Bridge with High-Rise Piers%铁路高墩大跨度连续刚构桥抗震设计分析

    Institute of Scientific and Technical Information of China (English)

    卢三平

    2015-01-01

    为保证在罕遇地震下桥梁结构满足规范要求,以主跨120 m的高墩大跨连续刚构桥———云南万拉木特大桥为例,运用M IDAS Civil建立连续刚构桥空间有限元模型,对其进行动力特性及罕遇地震作用下的非线性时程分析,并优化延性抗震设计。分析结果表明:桥梁振型以梁墩的横向振动为主,第1阶横向侧弯的自振周期为1.697 s ,全桥最大振幅出现在桥墩墩顶位置。在罕遇地震(50年超越概率为2%)作用下,中跨墩顶、底受力较大,均已进入屈服,但其弯矩均小于钢筋极限弯矩,桥梁满足“大震不倒”抗震性能目标。对塑性铰区进行优化,将墩底以上3m空心与实体分界位置处截面外层部分主筋弯折,形成最不利塑性铰区域;加强墩顶、底塑性铰区域横向约束钢筋布置,提高墩柱延性。%To ensure that the bridge structure could meet the code requirements under the ac‐tion of a rare earthquake ,the Wanlamu Bridge ,a long‐span continuous rigid‐fame bridge with a main span of 120 m and with high‐rise piers in Yunnan province ,was cited as an example for the study .The MIDAS Civil software was used to set up the finite element model of the continuous rigid‐frame bridge ,to examine the dynamic performance of the bridge ,carry out non‐linear time history analysis and optimize the ductile anti‐seismic design .The results of the analysis indicate that the transverse vibration of the piers is the dominant vibration mode of the bridge ,the natural vibration period of the 1st order transverse lateral bending is 1 .697s ,and the maximum vibration amplitude of the whole bridge was found at pier tops .Under the action of rare earthquakes (the exceedance probability in 50 years is 2% ) , the top and base of middle span piers bear heavier loads ,which has been identified in yielding period ;however ,the bending moment of the middle span piers is less than the

  4. Bridging the Gap

    DEFF Research Database (Denmark)

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska;

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures.......Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures....

  5. Bridging the Gap

    OpenAIRE

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska; Murdock, Karen; Schmidt, Iben Julie

    2015-01-01

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures. Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ve...

  6. Semiconductor bridge (SCB) detonator

    Science.gov (United States)

    Bickes, Jr., Robert W.; Grubelich, Mark C.

    1999-01-01

    The present invention is a low-energy detonator for high-density secondary-explosive materials initiated by a semiconductor bridge igniter that comprises a pair of electrically conductive lands connected by a semiconductor bridge. The semiconductor bridge is in operational or direct contact with the explosive material, whereby current flowing through the semiconductor bridge causes initiation of the explosive material. Header wires connected to the electrically-conductive lands and electrical feed-throughs of the header posts of explosive devices, are substantially coaxial to the direction of current flow through the SCB, i.e., substantially coaxial to the SCB length.

  7. 三岔双向挤扩灌注桩在桥梁设计中的应用%Application of Cast-in-place Pile with Expanded Branches and Bells by 3-way Extruding Arms in Bridge Design

    Institute of Scientific and Technical Information of China (English)

    张睿

    2016-01-01

    Through the design analysis of a bridge project pile,the cast-in-place piles with expanded branches and bells by 3-way extruding arms in the basic principle and design method are described in this paper and their vertical bearing capacity are calculated.The economic advantage and vertical bear-ing capacity advantage are verified,and the problems of its application in bridge engineering design are presented.%通过对某桥梁项目灌注桩的设计分析,阐述了三岔双向挤扩灌注桩的基本原理和设计方法,分别计算了三岔双向挤扩灌注桩与普通钻孔灌注桩的单桩竖向承载力,验证了三岔双向挤扩灌注桩在经济性及桩基竖向承载力等方面的优势,并提出了该桩基在桥梁工程设计中需要注意的问题。

  8. LLC半桥谐振变换器参数优化设计与实现%Design and Implementation of LLC Half-bridge Resonant Converter Parameter Optimization

    Institute of Scientific and Technical Information of China (English)

    叶湖; 周唯逸; 贾文超; 姜明伟

    2016-01-01

    Half-bridge LLC resonant converter of high efficiency and high power density is widely used to drive the LED light source. Through the analysis of its principle, characterization and the resonant network transmission efficiency, we summed up a simple parameter design method. This method designs the LLC half-bridge resonant circuit of 100kHz and 120W with 90% conversion efficiency. The results of experiment confirm the feasibility of the design method.%LLC半桥谐振变换器的高效率、高功率密度使其广泛应用于LED光源驱动器。通过对其工作原理、特性及谐振网络传输效率的分析,归纳出一种简易的参数设计方法。最后,用该方法设计了具有90%变换效率的100kHz、120W的LLC半桥谐振电路,实验结果证实了此设计方法的可行性。

  9. Design method and homogeneity control of bridge fair-faced concrete%桥梁清水混凝土设计方法与匀质性控制

    Institute of Scientific and Technical Information of China (English)

    周孝军; 牟廷敏; 丁庆军; 聂传振

    2015-01-01

    According to the structural characteristics of bridge engineering , the mix optimization design method of bridge fair‐faced concrete was presented , and C30 ~ C50 concrete with high cohesion and package ,outstanding fluidity and excellent mechanical properties were prepared .Through the test of air content of fresh concrete , micro hardness and micro structure in different parts of hardened concrete specimens ,effects of viscosity‐modifying admixtures on homogeneity of concrete were discussed . The results showed that the composition of bridge fair‐faced concrete were relatively homogeneous ,and the microstructure were relatively dense .When C30 concrete mixed with 5 × 10-5 cellulose ether or 6% silica fume (mass fraction of cementitious material ) ,air content of fresh concrete were less than 2% ,and slurry viscosity values were between 1 900 and 2 000 MPa · s .Also ,the micro hardness values in different parts of hardened concrete specimens were closed . The results were applied in practical bridge engineering , w hich generally meets the apparent quality requirements of bridge fair faced concrete .%根据桥梁工程结构特点,提出了桥梁清水混凝土的配合比优化设计方法,制备出粘聚性与包裹性好、流动度佳,且具有优良力学性能的C30~C50高性能清水混凝土。通过对混凝土拌合物含气量、硬化试件不同部位显微硬度与微观结构的测试,分析了增粘剂对其匀质性的影响规律。试验表明:对于C30桥梁清水混凝土,掺5×10-5的纤维素醚或掺6%的硅灰时,混凝土的含气量不超过2%,浆体旋转粘度值在1900~2000 M Pa · s之间,试件不同部位显微硬度值接近,匀质性好,结构密实。

  10. Case Study on 4000 m-span Cable-stayed Suspension Bridge

    OpenAIRE

    Haijun Wang; Jiandong Wang; Hua Wei

    2014-01-01

    This study describes the case studies for a cable-stayed suspension bridges proposed over the Tsugaru Strait, Japan. Center Bridge is designed as a compound bridge of suspension bridges and cable-stayed bridges with 4000 m super-long-span. Case studies about the effects of cable-stayed bridge length, the design of sub-cable, height and stiffness of main tower, type of foundation and length of side span on displacement were carried out. With appropriate design of above parameters, the compound...

  11. The Design and Use of the Bailey-Type Portable Steel Bridge for the Shenglian Island of the Kwan-yin Lake%观音湖圣莲岛贝雷式钢便桥的设计与使用

    Institute of Scientific and Technical Information of China (English)

    徐关尧; 田静; 李和; 朱杰

    2012-01-01

    Being 606 m(46×12 m+6 m+4×12 m) in total length,the portable steel bridge for the Shenglian Island of the Kwan-yin Lake is made up of Type-321 Bailey Panels.50 spans of this bridge are deck-type while the side span(the first span) is through-type.The choice of the designed loads and designed water levels for the bridge,the structural lay-out of the portable bridge and the points for attention in the design of the bridge are introduced in the paper,with technical measures for the use and maintenance of the bridge proposed.The vehicle test shows that the design meets the requirements.The practical use of the portable bridge proves the bridge safe and reliable,which helps speed up the developing progress of the Kwan-yin Lake.%观音湖圣莲岛钢便桥采用贝雷式321型桁架单元,总长度(46×12m+6m+4×12m),其中50跨为上承式结构,边跨(第1跨)为下承式结构。介绍了设计荷载、设计水位的选取、便桥的结构布置及设计注意事项,提出了钢便桥使用维护措施。通载试验表明设计符合要求。实际使用表明,圣莲岛钢便桥安全可靠,加快了圣莲岛开发建设进度。

  12. Fatigue classification of welded joints in orthotropic steel bridge decks

    NARCIS (Netherlands)

    Kolstein, M.H.

    2007-01-01

    This dissertation presents the research into fatigue classifications of welded joints in orthotropic steel bridge decks. These classifications are needed to calculate the fatigue life of these joints and should be included in the design codes. For years bridge design was mainly based on static loadi

  13. D4.2 Guideline for Load and Resistance Assessment of Existing European Railway Bridges - Sustainable Bridges - Assessment for future traffic demands and longer lives

    OpenAIRE

    EUROPEAN COMMISSION

    2007-01-01

    The bridge assessment in many aspects is very similar to the bridge design. The same basic principles lie at the heart of the process. Nevertheless, an important difference lies in the fact when a bridge is being designed, an element of conservatism is generally a good thing that can be achieved with very little additional costs. When a bridge is being assessed, it is important to avoid unnecessarily conservative measures because of the financial implications that may follow the decision of r...

  14. Composite timber-concrete road bridge structure

    Directory of Open Access Journals (Sweden)

    Stojić Dragoslav

    2007-01-01

    Full Text Available This work presents preliminary design of the road bridge made of laminated timber. The supporting system of the main bearing elements is made of the laminated timber in the system of arch with three joints; the bridge slab is designed as continuous slab, made of nine equal fields; each pair is made as composite timber-concrete beam, where the road slab is made of concrete and the needle pieces are made of timber. Fundament is based on HW piles. All the elements are designed to Eurocode.

  15. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated...

  16. The floating water bridge

    International Nuclear Information System (INIS)

    When high voltage is applied to distilled water filled in two glass beakers which are in contact, a stable water connection forms spontaneously, giving the impression of a floating water bridge. A detailed experimental analysis reveals static and dynamic structures as well as heat and mass transfer through this bridge

  17. Comprehensive Real-Time Bridge Health Monitoring System of Tongtai Bridge

    Directory of Open Access Journals (Sweden)

    Lei Su-su

    2015-01-01

    Full Text Available Tongtai Bridge is the world’s largest suspension curve-girder-skew-arch bridge, which is located in Zhangjiakou, China. The understanding of mechanics characteristics is limited to such complex bridges, so it is necessary to establish reliable health monitoring system to investigate the static and dynamic responses and monitor the safety of the bridge. A comprehensive real-time bridge health monitoring system is establish, which includes four aspects: sensor system, data acquisition and transmission system, data processing and control system, structure early warning and security assessment system. The paper systematically describes the system design principles, sensor layout, and monitoring content, then expounds system integration and function of each subsystem.

  18. Optimal design of initative horizontal bracing structure of middle tower column of southern cable stayed bridge of Xiazhang sea-crossing bridge%厦漳跨海大桥南汊斜拉桥索塔中塔柱主动横撑的设计计算

    Institute of Scientific and Technical Information of China (English)

    林寅

    2011-01-01

    本文介绍了厦漳跨海大桥南汊斜拉桥索塔施工中,为消除中塔柱倾斜塔柱根部混凝土的不良应力状态所采用的主动横撑结构的构造特点,以及考虑了施工因素的该结构的设计计算方法,确保中塔柱根部在施工过程中不开裂。该计算方法对类似工程具有一定的指导意义。%This paper intensively introduces the structural characteristics of the adoption of initiative horizontal bracing structure in order to eliminate the bad stress of concrete in the root of leaned tower column during the cable tower construction of Southern Cable Stayed Bridge of Xia Zhang Sea-crossing Bridge,as well as the structural design calculation method considering the construction factors,which can make sure that the root of leaned tower would not cracked during the construction process,and thie could be a reference for similar engineering.

  19. Research on Cultural Landscape Renewal Design of Historical Bridges in Rural and Urban Areas%城乡历史桥梁文化景观更变设计研究

    Institute of Scientific and Technical Information of China (English)

    李绪洪

    2012-01-01

    Based on the urgent need of studying cultural landscape renewal of historical bridges in the process of rural-urban modernization, this paper makes use of appropriate design methods of landscape renewal to explore the fundamental changes of the function and pattern of historical bridges in disrepair and to implement the landscape renewal from the perspective of optimization, integration, management and development. Furthermore, by recombining the historical districts and designing the intensive and interactive transportation function it is realized to make them be the leisure and recreation places for urban and rural residents.%针对目前城乡现代化迫切需要研究历史桥梁文化景观更变的特点,利用相应的景观更变设计方法,探索历史桥梁退役之后,功能、格局发生根本性改变,从优化、整合、经营、发展的角度来实施景观更变,与历史街区空间复合,交通功能集约一体化设计,成为适合城乡人民休闲游憩的场所.

  20. On design for concrete mix proportion C45 pile foundation at Hong Kong-Zhuhai-Macao Bridge%港珠澳大桥C45桩基混凝土配合比的设计

    Institute of Scientific and Technical Information of China (English)

    吴立斌; 郭冉冉; 李国刚

    2012-01-01

    The study undertakes the comparative optimization by applying the double mixed and separated addition of mineral admixtures, designs the C45 high-performance concrete which is suitable for the pile foundation construction at Hong Kong-Zhuhai-Macao Bridge and meets the high durability, and finds the fluidity of the separated addition fly ash is better than the one of the double mixed fly ash and mineral powder, and it can meet the design demands for the durability and strength, so it can be applied at large-diameter pile foundation construction, so as to provide the technical support for the pile foundation construction at later period of constructing Hong Kong-Zhuhai-Macao Bridge.%分别应用了双掺、单掺矿物掺合料的对比优化,设计出适合港珠澳大桥桩基施工并满足高耐久性的C45高性能混凝土,通过现场施工,发现单掺粉煤灰配比流动性优于双掺粉煤灰、矿粉,耐久性、强度均满足设计要求,更适用于大直径桩基施工,为港珠澳大桥桩基后期施工提供了技术支持。

  1. Solving Topological and Geometrical Constraints in Bridge Feature Model

    Institute of Scientific and Technical Information of China (English)

    PENG Weibing; SONG Liangliang; PAN Guoshuai

    2008-01-01

    The capacity that computer can solve more complex design problem was gradually increased.Bridge designs need a breakthrough in the current development limitations, and then become more intelli-gent and integrated. This paper proposes a new parametric and feature-based computer aided design (CAD) models which can represent families of bridge objects, includes knowledge representation, three-dimensional geometric topology relationships. The realization of a family member is found by solving first the geometdc constraints, and then the topological constraints. From the geometric solution, constraint equations are constructed. Topology solution is developed by feature dependencies graph between bridge objects. Finally, feature parameters are proposed to drive bridge design with feature parameters. Results from our implementation show that the method can help to facilitate bridge design.

  2. Aerodynamic stability of cable-stayed-suspension hybrid bridges

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-jun; SUN Bing-nan

    2005-01-01

    Three-dimensional nonlinear aerodynamic stability analysis was applied to study the aerodynamic stability of a cable-stayed-suspension (CSS) hybrid bridge with main span of 1400 meters, and the effects of some design parameters (such as the cable sag, length of suspension portion, cable plane arrangement, subsidiary piers in side spans, the deck form, etc.) on the aerodynamic stability of the bridge are analytically investigated. The key design parameters, which significantly influence the aerodynamic stability of CSS hybrid bridges, are pointed out, and based on the wind stability the favorable structural system of CSS hybrid bridges is discussed.

  3. 49 CFR 237.131 - Design.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Design. 237.131 Section 237.131 Transportation... TRANSPORTATION BRIDGE SAFETY STANDARDS Repair and Modification of Bridges § 237.131 Design. Each repair or... component of a bridge shall be designed by a railroad bridge engineer. The design shall specify the...

  4. Field Tests and Simulation of Lion-Head River Bridge

    Directory of Open Access Journals (Sweden)

    Yao-Min Fang

    2007-01-01

    Full Text Available Lion-Head River Bridge is a twin bridge in parallel position. The east-bounded was designed and constructed as a traditional prestress concrete box girder bridge with pot bearings; and the west-bounded was installed with seismic isolation devices of lead rubber bearings. The behavior of the isolated bridge is compared with that of the traditional bridge through several field tests including the ambient vibration test, the force vibration test induced by shakers, the free vibration test induced by a push and fast release system, and the truck test. The bridges suffered from various extents of damage due to the Chi-Chi and the Chi-I earthquakes of great strength during the construction and had been retrofitted. The damage was reflected by the change of the bridges' natural frequencies obtained from the ambient vibration tests. The models of the two bridges are simulated by the finite element method based on the original design drawings. Soil-structure interaction was also scrutinized in this study. The simulation was then modified based on the results from the field tests. Dynamic parameters of bridges are identified and compared with those from theoretical simulation. The efficiency is also verified to be better for an isolated bridge.

  5. 考虑残余位移影响的梁式桥基于性能的抗震设计%Study on performance-based seismic design for beam bridges considering residual displacement

    Institute of Scientific and Technical Information of China (English)

    李宇; 车艳阳; 王森

    2015-01-01

    According to the current Chinese code of bridge seismic design,320 strong motion records of four sites are selected to establish elastic-plastic displacement spectra,residual displacement spectra. Normalized parameters of cumulative dissipation energy are improved and equivalent ductility coefficients based on damage indexes are obtained. Furthermore,developed seismic damage models are discussed. Performance-based seismic design for bridges considering residual displacement is proposed and specific examples are provided to show the detailed design procedures. The nonlinear time-history analysis results show that both deformation capacity and energy dissipation capacity of bridge can be considered by the proposed method and the maximal displacement, plastic cumulative damage and residual displacement can be controlled well. The proposed method can be applied in design of low and medium-height piers with short natural period and low ductility.%以我国现行的桥梁抗震设计规范为依据,合理地选取4类场地320条强震记录,统计出适用于我国梁式桥抗震设计的弹塑性位移谱和残余位移谱,并改进正规化累积耗能参数,得到基于损伤性能指标的等效位移延性系数,并以此对桥梁的地震损伤模型进行探讨。在此基础上,提出考虑残余位移影响的梁式桥基于性能的抗震设计方法,并给出具体算例,其非线性时程分析的结果表明:该方法综合考虑了结构的变形和耗能能力,可有效地控制桥墩的首超破坏、塑性累积损伤以及震后残余位移,适用于我国短周期、低延性的一般规则梁式桥的中、低矮桥墩的抗震设计。

  6. Bridge technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. As LANs have proliferated, new technologies and system concepts have come to the fore. One of the key issues is how to interconnect networks. One means of interconnection is to use a 'bridge'. Other competing technologies are repeaters, routers, and gateways. Bridges permit traffic isolation, connect network segments together and operate at the MAC layer. Further, because they operate at the MAC layer, they can handle a variety of protocols such as TCP/IP, SNA, and X.25. This report focuses on the specific technology of bridging two netw

  7. 高架桥薄壁空心高墩施工%Construction Organizational Design for High Hollow Thin-wall Pier of Viaduct Bridge

    Institute of Scientific and Technical Information of China (English)

    冯世敏

    2014-01-01

    PJ-200 Cantilever formwork ( climbing formwork ) and big steel formwork lifted with tower crane ( turnover formwork construction) have been adopted for the construction of high hollow thin-wall pier of Hewei Bridge at Km:253+353 of Lechang-Guangzhou Expressway, which has achieved good economic benefits.%乐昌至广州高速公路K253+353河尾大桥薄壁空心高墩施工组织设计采用PJ-200悬臂模板(即爬模施工)和塔吊提升大块钢模的方法施工(即翻模施工)相结合的方式,取得了较好的经济效益。

  8. Molecular Design of Crown Ethers. 191. Synthesis of Novel Disulfide- and Diselenide-Bridged Bis (benzo-12-crown-4)s and their Ag+ Selective Electrode Properties

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Two novel heteroatom-bridged bis (benzo-12-crown-4 ether)s, i.e. bis [2-nitro-4,5-(1,4,7,10-tetraoxadecamethylene)phenyl] disulfide 1 and diselenide 2, have been synthesized. X-ray crystallographic structure was obtained for 1. Ion selective electrodes (ISE) for Ag+, containing 1 and 2 in PVC membrane as neutral carriers, were prepared, and their selectivity coefficients for Ag+ (KpolAg,M) were determined against other heavy metal ions, alkali and alkaline-earth metal ions, and ammonium ion. These ISEs showed excellent Ag+ selectivities, log (KpolAg,M) -3.8, against most of the interfering cations examined, except for Hg+.

  9. Bridging the Gap between User Experience Research and Design in Industry: An Analysis of Two Common Communication Tools--Personas and Scenarios

    Science.gov (United States)

    Putnam, Cynthia

    2010-01-01

    User experience (UX) research in the design of technology products utilizes human-centered design (HCD) methods to summarize and explain pertinent information about end users to designers. However, UX researchers cannot effectively communicate the needs and goals of users if designers do not find UX research (a) easy to integrate into design…

  10. Multivariate Feature Selection for Predicting Scour-Related Bridge Damage using a Genetic Algorithm

    Science.gov (United States)

    Anderson, I.

    2015-12-01

    Scour and hydraulic damage are the most common cause of bridge failure, reported to be responsible for over 60% of bridge failure nationwide. Scour is a complex process, and is likely an epistatic function of both bridge and stream conditions that are both stationary and in dynamic flux. Bridge inspections, conducted regularly on bridges nationwide, rate bridge health assuming a static stream condition, and typically do not include dynamically changing geomorphological adjustments. The Vermont Agency of Natural Resources stream geomorphic assessment data could add value into the current bridge inspection and scour design. The 2011 bridge damage from Tropical Storm Irene served as a case study for feature selection to improve bridge scour damage prediction in extreme events. The bridge inspection (with over 200 features on more than 300 damaged and 2,000 non-damaged bridges), and the stream geomorphic assessment (with over 300 features on more than 5000 stream reaches) constitute "Big Data", and together have the potential to generate large numbers of combined features ("epistatic relationships") that might better predict scour-related bridge damage. The potential combined features pose significant computational challenges for traditional statistical techniques (e.g., multivariate logistic regression). This study uses a genetic algorithm to perform a search of the multivariate feature space to identify epistatic relationships that are indicative of bridge scour damage. The combined features identified could be used to improve bridge scour design, and to better monitor and rate bridge scour vulnerability.

  11. 基于qtopia的桥梁检测车防侧翻监控系统的设计与实现%The design and realization of anti-rollover monitoring systerm of bridge-detection vehicle based on qtopia

    Institute of Scientific and Technical Information of China (English)

    杨世华; 王秀敏; 李世忠

    2011-01-01

    针对桥梁检测车在检测过程中存在的安全隐患,设计了一款基于qtopia的防侧翻监控系统,该系统以ARM9处理器为硬件核心,采取串口通信的方式,对来自传感器的信号经过处理,把机械臂的动作以动态图形显示在LCD屏上,克服了视频监控系统无法全角度监控的弊端.经过安装测试,证明该系统响应快速,运行稳定,具有实用价值.%In order to overcoming the hidden danger in the process of bridge-detection vechile detecting the bridge, a new anti-rollover monitoring systerm based qtopia is designed. In the systerm, ARM9 is adopted as the hard ware-core, and serial communication is taken as the way of data communication. After being processed, the signals from the sensors can display and simulate the robot arm movements in the LCD screen by dynamic graphic. It's better than video monitoring system, which can not give the whole view of arm movements. After being installed and tested, the systerm has been proved to be high-speed response, stable and functional.

  12. Bridged Race Population Estimates

    Data.gov (United States)

    U.S. Department of Health & Human Services — Population estimates from "bridging" the 31 race categories used in Census 2000, as specified in the 1997 Office of Management and Budget (OMB) race and ethnicity...

  13. Long Span Bridges in Scandinavia

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1998-01-01

    The first Scandinavian bridge with a span of more than 500 m was the Lillebælt Suspension Bridge opened to traffic in 1970.Art the end of the 20th century the longest span of any European bridge is found in the Storebælt East Bridge with a main span of 1624 m. Also the third longest span in Europ...

  14. Standard plans for southern pine bridges. Forest Service general technical report

    Energy Technology Data Exchange (ETDEWEB)

    Hilbrich Lee, P.D.; Ritter, M.A.; Triche, M.

    1995-09-01

    This publication contains standardized designs and details for three timber bridge superstructure types, including stress-laminated sawn lumber bridges, stress laminated glued laminated timber (glulam) bridges, and longitudinal sawn lumber stringer bridges with transverse plank decks. Each set of plans encompasses numerous span length and width combinations, design loadings for AASHTO HS 20-44 and HS 25-44 vehicles, and two options for live-load deflection criteria.

  15. Bridging the Educational Research-Teaching Practice Gap: Curriculum Development, Part 1--Components of the Curriculum and Influences on the Process of Curriculum Design

    Science.gov (United States)

    Anderson, Trevor R.; Rogan, John M.

    2011-01-01

    This article summarizes the major components of curriculum design: vision, operationalization of the vision, design, and evaluation. It stresses that the relationship between these components is dynamic, and that the process of curriculum design does not proceed via a linear application of these components. The article then summarizes some of the…

  16. Aerodynamic stability of cable-supported bridges using CFRP cables

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-jun; YING Lei-dong

    2007-01-01

    To gain understanding of the applicability of carbon fiber reinforced polymer (CFRP) cable in cable-supported bridges, based on the Runyang Bridge and Jinsha Bridge, a suspension bridge using CFRP cables and a cable-stayed bridge using CFRP stay cables are designed, in which the cable's cross-sectional area is determined by the principle of equivalent axial stiffness.Numerical investigations on the aerodynamic stability of the two bridges are conducted by 3D nonlinear aerodynamic stability analysis. The results showed that as CFRP cables are used in cable-supported bridges, for suspension bridge, its aerodynamic stability is superior to that of the case using steel cables due to the great increase of the torsional frequency; for cable-stayed bridge,its aerodynamic stability is basically the same as that of the case using steel stay cables. Therefore as far as the wind stability is considered, the use of CFRP cables in cable-supported bridges is feasible, and the cable's cross-sectional area should be determined by the principle of equivalent axial stiffness.

  17. A cloud-based information repository for bridge monitoring applications

    Science.gov (United States)

    Jeong, Seongwoon; Zhang, Yilan; Hou, Rui; Lynch, Jerome P.; Sohn, Hoon; Law, Kincho H.

    2016-04-01

    This paper describes an information repository to support bridge monitoring applications on a cloud computing platform. Bridge monitoring, with instrumentation of sensors in particular, collects significant amount of data. In addition to sensor data, a wide variety of information such as bridge geometry, analysis model and sensor description need to be stored. Data management plays an important role to facilitate data utilization and data sharing. While bridge information modeling (BrIM) technologies and standards have been proposed and they provide a means to enable integration and facilitate interoperability, current BrIM standards support mostly the information about bridge geometry. In this study, we extend the BrIM schema to include analysis models and sensor information. Specifically, using the OpenBrIM standards as the base, we draw on CSI Bridge, a commercial software widely used for bridge analysis and design, and SensorML, a standard schema for sensor definition, to define the data entities necessary for bridge monitoring applications. NoSQL database systems are employed for data repository. Cloud service infrastructure is deployed to enhance scalability, flexibility and accessibility of the data management system. The data model and systems are tested using the bridge model and the sensor data collected at the Telegraph Road Bridge, Monroe, Michigan.

  18. Theoretical mechanics: Crowd synchrony on the Millennium Bridge

    Science.gov (United States)

    Strogatz, Steven H.; Abrams, Daniel M.; McRobie, Allan; Eckhardt, Bruno; Ott, Edward

    2005-11-01

    Soon after the crowd streamed on to London's Millennium Bridge on the day it opened, the bridge started to sway from side to side: many pedestrians fell spontaneously into step with the bridge's vibrations, inadvertently amplifying them. Here we model this unexpected and now notorious phenomenon - which was not due to the bridge's innovative design as was first thought - by adapting ideas originally developed to describe the collective synchronization of biological oscillators such as neurons and fireflies. Our approach should help engineers to estimate the damping needed to stabilize other exceptionally crowded footbridges against synchronous lateral excitation by pedestrians.

  19. 崇启大桥C35承台混凝土配合比设计与优化%Mix proportion design and optimization for C35 pile concrete of Chongqi bridge

    Institute of Scientific and Technical Information of China (English)

    刘冠国; 马爱斌; 秦鸿根; 张萍

    2015-01-01

    以崇启大桥承台混凝土施工为依托,结合大体积混凝土质量控制关键点,提出配合比设计方案,通过对混凝土的工作性能、力学性能及各项耐久性性能的分析和研究,最终得到配合比优化方案。%For the construction of platform concrete of Chongqi bridge and combined with key points of quality control,the mix designs were proposed. The finally mix proportion was obtained through the study of work performace,mechanical properties and durability per-formance.

  20. Very High Frequency Half Bridge DC/DC Converter

    DEFF Research Database (Denmark)

    Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.

    2014-01-01

    This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all...

  1. DSTATCOM Based Design and Analysis of Phase Shifted and Level Shifted Cascaded H-Bridge Multilevel Inverter for Power Quality Enhancement

    Directory of Open Access Journals (Sweden)

    Ch. Rama Krishna

    2014-04-01

    Full Text Available In general, existing cQA forums provide only textual answers, which are not informative enough for many questions. Conventional MMQA aims to seek multimedia answers without the assistance of textual answers. This MMQA scheme using diversification method is able to enrich textual answers in cQA with appropriate meta data which improves the informativeness and it bridges two gaps (i The gap between questions and textual answers (ii The gap between textual answer and multimedia answer. This scheme consists of three components: answer medium selection, query generation and data selection and presentation. This scheme determines the type of media information that can be added for a textual answer. This scheme predicts the type of medium to be added using Naïve Bayes Classifier, it automatically generates query based on QA knowledge and performs multimedia search. Finally this scheme performs query adaptive re-ranking and duplicate removal to obtain a set of images and videos for presentation along with textual answer. This scheme uses diversification methods to make the enriched media data more diverse. This scheme uses Page Ranking algorithm to retrieve more relevant and diverse search results.

  2. 天兴洲大桥提升站设计及安装控制%Design and assemble control of lifting station of Tianxingzhou Bridge

    Institute of Scientific and Technical Information of China (English)

    金永忠

    2011-01-01

    Introduced construction technology of box-beam MSS assemble and lifting in Tianxingzhou Changjiang Bridge, including the calculation of bearing capacity of foundation soil, strength calculation of the steel columns and box-beam lifting, the calculation of structural stability, and the key points of lifting station installation. The integral lifting and installation can speed up process of construction and guarantee the quality of construction. Practice indicates, movable shuttering form lifting had its own features and advantages, which was confirmed safe and controllable, and simple to operate.%介绍了天兴洲公铁两用长江大桥铁路箱梁移动模架整体提升施工方法,主要包括地基承载力、钢管立柱、吊装钢箱梁的设计计算,结构稳定性计算,以及提升站安装时应该控制要点.实践表明,移动模架整体提升加快施工速度,移动模架的结构质量也易于保证;移动模架整体吊装有其自身特点和优势,在施工中安全可控,操作简单.

  3. Truck-based mobile wireless sensor networks for the experimental observation of vehicle–bridge interaction

    International Nuclear Information System (INIS)

    Heavy vehicles driving over a bridge create a complex dynamic phenomenon known as vehicle–bridge interaction. In recent years, interest in vehicle–bridge interaction has grown because a deeper understanding of the phenomena can lead to improvements in bridge design methods while enhancing the accuracy of structural health monitoring techniques. The mobility of wireless sensors can be leveraged to directly monitor the dynamic coupling between the moving vehicle and the bridge. In this study, a mobile wireless sensor network is proposed for installation on a heavy truck to capture the vertical acceleration, horizontal acceleration and gyroscopic pitching of the truck as it crosses a bridge. The vehicle-based wireless monitoring system is designed to interact with a static, permanent wireless monitoring system installed on the bridge. Specifically, the mobile wireless sensors time-synchronize with the bridge's wireless sensors before transferring the vehicle response data. Vertical acceleration and gyroscopic pitching measurements of the vehicle are combined with bridge accelerations to create a time-synchronized vehicle–bridge response dataset. In addition to observing the vehicle vibrations, Kalman filtering is adopted to accurately track the vehicle position using the measured horizontal acceleration of the vehicle and positioning information derived from piezoelectric strip sensors installed on the bridge deck as part of the bridge monitoring system. Using the Geumdang Bridge (Korea), extensive field testing of the proposed vehicle–bridge wireless monitoring system is conducted. Experimental results verify the reliability of the wireless system and the accuracy of the vehicle positioning algorithm

  4. Truck-based mobile wireless sensor networks for the experimental observation of vehicle-bridge interaction

    Science.gov (United States)

    Kim, Junhee; Lynch, Jerome P.; Lee, Jong-Jae; Lee, Chang-Geun

    2011-06-01

    Heavy vehicles driving over a bridge create a complex dynamic phenomenon known as vehicle-bridge interaction. In recent years, interest in vehicle-bridge interaction has grown because a deeper understanding of the phenomena can lead to improvements in bridge design methods while enhancing the accuracy of structural health monitoring techniques. The mobility of wireless sensors can be leveraged to directly monitor the dynamic coupling between the moving vehicle and the bridge. In this study, a mobile wireless sensor network is proposed for installation on a heavy truck to capture the vertical acceleration, horizontal acceleration and gyroscopic pitching of the truck as it crosses a bridge. The vehicle-based wireless monitoring system is designed to interact with a static, permanent wireless monitoring system installed on the bridge. Specifically, the mobile wireless sensors time-synchronize with the bridge's wireless sensors before transferring the vehicle response data. Vertical acceleration and gyroscopic pitching measurements of the vehicle are combined with bridge accelerations to create a time-synchronized vehicle-bridge response dataset. In addition to observing the vehicle vibrations, Kalman filtering is adopted to accurately track the vehicle position using the measured horizontal acceleration of the vehicle and positioning information derived from piezoelectric strip sensors installed on the bridge deck as part of the bridge monitoring system. Using the Geumdang Bridge (Korea), extensive field testing of the proposed vehicle-bridge wireless monitoring system is conducted. Experimental results verify the reliability of the wireless system and the accuracy of the vehicle positioning algorithm.

  5. Investigation of Aerodynamic Interference of Double Deck Bridges

    Energy Technology Data Exchange (ETDEWEB)

    Sitek, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Bojanowski, C. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC)

    2016-05-01

    Construction of a twin bridge can be a cost effective and minimally disruptive way to increase capacity when an existing bridge is not near the end of its service life. With ever growing vehicular traffic, when demand approaches the capacity of many existing roads and bridges. Remodeling a structure with an insufficient number of lanes can be a good solution in case of smaller and less busy bridges. Closing down or reducing traffic on crossings of greater importance for the construction period, however, can result in major delays and revenue loss for commerce and transportation as well as increasing the traffic load on alternate route bridges. Multiple-deck bridges may be the answer to this issue. A parallel deck can be built next to the existing one, without reducing the flow. Additionally, a new bridge can be designed as a twin or multi-deck structure. Several such structures have been built throughout the United States, among them: - The New NY Bridge Project - the Tappan Zee Hudson River Crossing, - SR-182 Columbia River Bridge, - The Thaddeus Kosciusko Bridge (I-87), - The Allegheny River Bridge, Pennsylvania, which carries I76, - Fred Hartman Bridge, TX, see Figure 1.2. With a growing number of double deck bridges, additional, more detailed, studies on the interaction of such bridge pairs in windy conditions appears appropriate. Aerodynamic interference effects should be examined to assure the aerodynamic stability of both bridges. There are many studies on aerodynamic response of single deck bridges, but the literature on double-deck structures is not extensive. The experimental results from wind tunnels are still limited in number, as a parametric study is required, they can be very time consuming. Literature review shows that some investigation of the effects of gap-width and angle of wind incidence has been done. Most of the CFD computational studies that have been done were limited to 2D simulations. Therefore, it is desirable to investigate twin decks

  6. 武汉鹦鹉洲长江大桥北锚碇新型沉井基础设计%Design of New Type Caisson Foundation for North Anchorage of Yingwuzhou Changjiang River Bridge in Wuhan

    Institute of Scientific and Technical Information of China (English)

    李明华; 杨灿文

    2011-01-01

    The main bridge of Yingwuzhou Changjiang River Bridge in Wuhan is a three-tower and four-span suspension bridge. After comparison of different design proposals, it was determined that a new type caisson structure of circular cross section and with multiple round wells would be used for the north anchorage foundation of the bridge. In the big size well in the center of the caisson, the crisscross diaphragm was set and along the periphery within the caisson, a number of small size wells were uniformly set. The caisson is 43 m high and has totally 8 lifts, of which the first lift is a steel shell concrete caisson and the rest parts of the caisson from the second to the eighth lifts are all of reinforced concrete caissons. In the construction of the caisson, the caisson was sunk down by no dewatering and the air curtain was provided in the caisson wall to reduce sinking difficulty and construction risk. The software FLAC3D was used to conduct numerical simulation and analysis of the construction process of the sinking and to evaluate the construction safety, the environmental effect caused by the construction and the deformation of the foundation to be applied with load after the bridge was put into operation. The results of the a-nalysis show that in the process of sinking the caisson in lifts, the caisson structure and ground deformation can meet the relevant requirements in the codes and the adverse influence of the construction on the ambient buildings and the river dyke can be effectively avoided.%武汉鹦鹉洲长江大桥主桥为三塔四跨悬索桥.该桥北锚碇基础经多方案比选采用多圆孔环形截面新型沉井结构.沉井中间大圆孔内设置十字形隔墙,圆环内沿圆周均布有小直径井孔.沉井总高43 m,共分8节,第1节为钢壳混凝土沉井,第2~8节均为钢筋混凝土沉井.北锚碇施工中采用不排水下沉、井壁增加空气幕等措施减小施工难度及风险.采用软件FLAC3D对沉井施工过程进

  7. The Memory Bridge Initiative on Service Learners

    Science.gov (United States)

    Wescott, Amy; Healy, Tara C.

    2011-01-01

    This study evaluated the Memory Bridge Initiative (MBI), an educational, experiential program pairing high school students with older adults who have dementia. A qualitative, single group design with baseline and follow-up measures examined whether or not students would have a positive learning experience while gaining newfound appreciation and…

  8. The Bridge of Mandolin County

    Science.gov (United States)

    Lantz, Juliette M.; Feindt, Jenny E.; Lewellyn, Eric P. B.; Walczak, Mary M.

    1999-12-01

    The Bridge of Mandolin County is a case designed to teach the general chemistry principles of molar mass, ions and aqueous reactions, solubility rules, and inorganic nomenclature. Through the instructor-facilitated class discussion, students consider the options before the Mandolin Town Council regarding deicing the newly constructed bridge connecting Mandolin with a large nearby city. The students must decipher contradictory claims made on behalf of sodium chloride, the traditional deicer, and calcium magnesium acetate, a new environmentally friendly deicer, to arrive at the most cost-effective and environmentally appropriate deicing product. As they work through the analysis they raise questions that can be addressed in a laboratory setting. Four optional role-playing experiments are included, which can be used by the students to gather information helpful to resolution of the case. The case is intended to be used over two class periods, with a laboratory period in between, though suggestions for other models are provided. Laboratory procedures include an EDTA titration for Ca2+ and Mg2+, a gravimetric analysis, a qualitative examination of ions and solubility, an introduction to freezing point depression and measurement, and an experimental design activity. This case can also successfully be used without alteration in non-majors chemistry or environmental chemistry courses, or upper-level analytical or environmental chemistry courses.

  9. LLC半桥谐振变换器参数设计法的比较与优化%Comparison and Optimization for LLC Half-bridge Resonant Converter Parameter Design

    Institute of Scientific and Technical Information of China (English)

    江雪; 龚春英

    2009-01-01

    LLC half-bridge resonant converter has been widely studied due to advantages of high efficiency and high power density.The accurate parameters can create a precondition for LLC resonant converter to achieve high efficiency and satis-factory soft switching.A parameter design strategy based on frequency domain is described,a more accurate design strategy is introduced based on frequency and time domains in order to optimize the parameter.A I,LC resonant converter prototype which employ the latter strategy is designed and the results verify the feasibility of the strategy.%LLC半桥谐振变换器以其高效率、高功率密度等优点成为研究的热门拓扑.合理选择其参数的是实现变换器高工作效率.优良软开关特性的前提和保证.介绍了一种皋丁频域分析的参数设计方法,在总结其优缺点的基础上给出一种更为精确的频域、时域相结合的方法.通过优化参数设计,并根据该设计策略制作了一台LLC半桥谐振变换器样机,以验证所述方法的可行性.

  10. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

  11. 波司登长江大桥拱肋高性能混凝土设计与试验%Design and test of high-performance arch rib concrete of Bosideng Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    王建军; 李冉; 谢开仲

    2015-01-01

    为得到主跨530 m的中承式钢管混凝土桁架拱桥———波司登长江大桥的拱肋管内C60高性能混凝土混凝土基准配合比,采用密实骨架堆积法进行设计,得到初步配合比为水泥:粉煤灰:砂:石子:水=430:140:701:1041:156。以初步配合比为基础进行制备和试验,优化了胶凝材料体系,硅灰掺量确定为30 kg/m3,经过对混凝土的工作性能和力学性能进行试验检验,最终确定满足大桥使用性能要求的基准配合比为水泥:粉煤灰:硅灰:砂:石:水=430:110:30:701:1041:156。%To determine the reference mixing proportion of the high-performance C60 concrete used in the arch rib of Bosideng Yangtze River Bridge which is a half-through concrete filled steel tube ( CFST) truss arch bridge with a main span of 530 m, the dense frame accumulation method was a-dopted in design, and a preliminary mixing proportion of cement :fly ash( FA) :sand :gravel :water=430:140:701:1041:156 was obtained. Based on the proportion, the concrete was prepared, a test was conducted and the cementitious material system was optimized. The mixing amount of silica fume was determined to be 30 kg/m3 . After the test verification about the working performance and mechanical properties, a reference mixing proportion of the concrete for the bridge was determined as cement :FA :Silica fume(SF) :sand :gravel :water=430:110:30:701:1041:156.

  12. Planar Hall effect bridge magnetic field sensors

    DEFF Research Database (Denmark)

    Henriksen, A.D.; Dalslet, Bjarke Thomas; Skieller, D.H.;

    2010-01-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can...... be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar...... Hall effect bridge sensors....

  13. Planar Hall effect bridge magnetic field sensors

    Science.gov (United States)

    Henriksen, A. D.; Dalslet, B. T.; Skieller, D. H.; Lee, K. H.; Okkels, F.; Hansen, M. F.

    2010-07-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar Hall effect bridge sensors.

  14. Simulation of the Whole Process of Ship-Bridge Collision

    Institute of Scientific and Technical Information of China (English)

    刘建成; 顾永宁

    2002-01-01

    The simulation of the whole ship-bridge collision process can be effectively carried out by nonlinear dynamic finiteelement method. Based on the simple description of the theory, a scenario of a 40000 DWT oil tanker colliding with abridge across the Yangtze River is designed for simulation. The technology of structure modeling and the determination ofrelated parameters are introduced. The deformation of the bulb bow, the history of collision force change, the exchange ofcollision energy and the stress distribution of the bridge pier are described in detail, which are of great value to bridge de-sign and bridge pier damage estimation, Some mechanical characters in the process of ship-bridge collision are described.More accurate results can be produced by finite element method than that by empirical formulas and simplified analyticalmethods.

  15. Microwave generation and complex microwave responsivity measurements on small Dayem bridges

    DEFF Research Database (Denmark)

    Pedersen, Niels Falsig; Sørensen, O; Mygind, Jesper;

    1977-01-01

    Measurements of the active properties of a Dayem micro-bridge at X-band frequencies is described. The bridge was mounted in a microwave cavity designed to match the bridge properly and the microwave output from the cavity was detected using a sensitive X-band spectrometer. Microwave power...

  16. 基于LPC2214的ZVZCS-PWM全桥变换控制器的研究%Design of Phase-Shifted Full-Bridge ZVZCS Converter Based on ARM

    Institute of Scientific and Technical Information of China (English)

    龚希宾

    2009-01-01

    Convertional full-bridge Zero-Voltage and Zero-Current switching(ZVZCS)PWM DC-DC converters exist some disadvantages in the operating process of ZCS for lagging leg. These problems include additional losses in auxiliary cir-cuit, complicated realization for soft-switching, and high voltage and curent stresses of switches. A full-bridge ZVZCS PWM DC-DC converter with coupled output inductor was proposed to resolve these issues. The soft-switching operating principle of the converter was analyzed, and digital control system was designed using ARM chip LCP2214. A prototype has verified the principle and characteristics of the proposed soft-switching convener and the feasibility of the digital control system.%针对传统ZVZCS-PWM DC/DC全桥变换器在实现滞后桥臂开关管零电流开关过程中,存在着辅助谐振电路附加损耗较大,软开关实现方式复杂,功率开关管电压应力和电流应力高等缺点,介绍了一种新型次级箝位移相控制的ZVZCS PWM DC/DC全桥变换器.文中分析了该变换器实现软开关的原理,同时设计了变换器数字控制系统,控制器采用LPC2214型ARM芯片,并通过一台实验样机验证了这种软开关变换器相关理论的正确性以及该数字控制系统的可行性.

  17. Design and Analysis of Cable-pylon Anchorage Zone for Huaian Minj iang Bridge in Fuzhou%福州淮安闽江大桥索塔锚固区设计与分析

    Institute of Scientific and Technical Information of China (English)

    朱朝阳

    2016-01-01

    斜拉桥索塔锚固区受力复杂,对全桥结构安全具有重大影响。结合斜拉桥混凝土桥塔工程实例,介绍了主塔锚固区的设计思路,采用有限元软件建立实体模型研究锚固区应力分布情况和受力特性。结果表明:设置环向预应力对主塔锚固区侧壁受力改善显著,锚固齿块应力集中明显,应适当加大齿块尺寸,加强锚下配筋和横向钢筋配置。%The structure behavior of cable-pylon anchorage zone is complicated,and it has a great in-fluence on the safety of the whole bridge structure.Based on the example of cable-stayed bridge con-crete tower proj ect,the design mentality of cable-pylon anchorage zone was introduced,and the solid models was set up by using finite element software to analyze the stress distribution and mechanical characteristic of cable-pylon anchorage zone.The results show that:setting ring pre-stress can signifi-cantly improve the sidewall's stress states of cable-pylon anchorage zone,the stress concentration of anchor block lower edge is distinct,anchor block size should be increased properly and the disposition steel bar under anchorage and the transverse steel bar should be strengthened.

  18. 基于无线网桥传输气吸式免耕播种机振动测试系统设计%Tillage Planter Vibration Test System Design Based on Wireless Transmission of Air-suction Bridge

    Institute of Scientific and Technical Information of China (English)

    张旭; 刘飞; 董帅; 赵满全

    2015-01-01

    针对气吸式免耕播种机在空旷的田间试验不便应用有线传输的特点,采用加速度传感器测量振动的方法,设计了一种综合无线传输技术和振动信号采集与分析的振动测量系统。系统选用 Ti3058 k-16 M 的无线网桥、加速度传感器和数据采集卡实现了振动测量信号的采集和无线传送, MatLab 分析处理采集到的数据。试验表明:系统在田间试验稳定性好、抗干扰能力强、网桥传输数据范围广、便捷实用,可为气吸式免耕播种机的田间测振试验提供方便。%For air-suction tillage planter in the open field test cable transmission characteristics inconvenience applica -tions, Measurement method using the acceleration sensor of vibration , designed an integrated wireless transmission tech-nology and vibration signal acquisition and analysis of vibration measurement system , system used Ti3058k-16M wireless bridge , acceleration sensor and data acquisition card for the vibration measurement signal acquisition and wireless trans -mission , MATLAB analysis and processing the collected data .Experimental results show that:system stability in field tri-als, anti-interference ability , bridge a wide range of data transmission , Convenient and practical , To facilitate air-suc-tion tillage planter field vibration tests .

  19. Shaking Table Tests of Curved Bridge considering Bearing Friction Sliding Isolation

    Directory of Open Access Journals (Sweden)

    Lei Yan

    2016-01-01

    Full Text Available Specific to severe damage to curved bridges in earthquakes caused by the excessive force of the fixed bearings and piers, a new seismic design method on curved bridges considering bearing friction sliding isolation is proposed in this paper. Seismic model bridge and isolation model bridge with similarity ratio of 1/20 were made and the shaking table comparison test was conducted. The experimental results show that the isolation model curved bridge suffered less seismic damage than the seismic model curved bridge. The fundamental frequencies of the seismic model bridge and isolation model bridge decreased and the damping ratio increased with the increase of seismic intensity. Compared with seismic curved bridge, the maximum reduction rates of peak acceleration along the radial and tangential directions on the top of pier of the isolation model curved bridge were 47.3% and 55.5%, respectively, and the maximum reduction rate of the peak strain on the bottom of pier of the isolation model curved bridge was 43.4%. For the isolation model curved bridge, the maximum reduction rate of peak acceleration on the top of pier was 24.6% compared with that on the bottom of pier. The study results can provide experimental basis for the seismic design of curved bridges.

  20. Application of system-based correction factors in condition rating of steel-composite bridges

    OpenAIRE

    Casas Rius, Joan Ramon; Anitori, Giorgio; ghosn, michel

    2016-01-01

    Traditional condition rating procedures concentrate on member condition and give no consider-ation to system behavior. In this paper a methodology is proposed to modify the correction factor applied dur-ing the assignment of bridge condition rating to account for bridge system behavior. Robustness and redun-dancy concepts that have been used in the past for structural design of new bridges and for assessment of existing bridges are in this work extended to condition rating, which represents t...

  1. Effect of material uncertainties on dynamic response of segmental box girder bridge

    OpenAIRE

    Suchart Limkatanyu; Kittisak Kuntiyawichai

    2007-01-01

    The main objective of this paper was to investigate the effect of material uncertainties on dynamic response of segmental box girder bridge subjected to a moving load, in this case a rapid passing trains. Literatures concerned with the design of segmental box girder bridge, the application of finite element analysis to model the segmental box girder bridge, and the minimum requirement for structural conditions of the bridge were described and discussed in detail. A series of finite element a...

  2. Quantum Bidding in Bridge

    Science.gov (United States)

    Muhammad, Sadiq; Tavakoli, Armin; Kurant, Maciej; Pawłowski, Marcin; Żukowski, Marek; Bourennane, Mohamed

    2014-04-01

    Quantum methods allow us to reduce communication complexity of some computational tasks, with several separated partners, beyond classical constraints. Nevertheless, experimental demonstrations of this have thus far been limited to some abstract problems, far away from real-life tasks. We show here, and demonstrate experimentally, that the power of reduction of communication complexity can be harnessed to gain an advantage in a famous, immensely popular, card game—bridge. The essence of a winning strategy in bridge is efficient communication between the partners. The rules of the game allow only a specific form of communication, of very low complexity (effectively, one has strong limitations on the number of exchanged bits). Surprisingly, our quantum technique does not violate the existing rules of the game (as there is no increase in information flow). We show that our quantum bridge auction corresponds to a biased nonlocal Clauser-Horne-Shimony-Holt game, which is equivalent to a 2→1 quantum random access code. Thus, our experiment is also a realization of such protocols. However, this correspondence is not complete, which enables the bridge players to have efficient strategies regardless of the quality of their detectors.

  3. Bridge of Light

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Lying gleaming white under a brooding sky,the Lhasa River Railway Bridge forms a gate to Lhasa City.Built as a part of Qinghai-Tibet Railway,on July 1,2011, the highest altitude railway in the world has been in service for five years. Lhasa,Tibet

  4. Bridge over troubled water?

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Nannestad, Peter; Svendsen, Gert Tinggaard

    2008-01-01

    The problem of integrating non-Western immigrants into Western welfare states is the focus of this paper. To address this issue, we suggest a social capital approach in which we apply the conceptual pair of bridging social capital (BR), which connects an individual to the broader social structure...

  5. Building Bridges to China.

    Science.gov (United States)

    Wasta, Stephanie; Scott, Margaret

    1998-01-01

    Describes a theme cycle called "Building Bridges to China" developed for third grade students that focuses on the similarities between the lives of children and families in China and the United States. Explains that the theme cycle addresses the National Geography Standards and three of the National Council for the Social Studies standards. (CMK)

  6. 浅析公路桥梁中板式橡胶支座设计%Simple Analysis on Laminated Rubber Bearing Design in Highway Bridge Construction

    Institute of Scientific and Technical Information of China (English)

    马少卿

    2015-01-01

    In this paper ,relevant law s and regulations about design methods of laminated rubber bearing are clarified and existing defects in design are further discussed .%本文主要对我国相关法律对公路桥梁中板式橡胶支座设计方法的规定进行了概述,进而探讨了公路桥梁中板式橡胶支座设计存在的漏洞。

  7. Advanced assessment methods for elderly bridges. State-of-the-art and justification based on LCA

    OpenAIRE

    Soriano Chacón, Miriam

    2013-01-01

    [ANGLÈS] Many of the existing bridges do not satisfy the structural requirements specified in design codes for new bridges. However, many of these bridges must remain in service and therefore decisions must be made in order to maintain their safety. In the design of new bridges, it is accepted “to be on the safe side” inherent in the standards; but for an assessment of an elderly bridge this procedure should be removed in order to have a more realistic understanding of the stat...

  8. 南水北调工程交通桥高性能混凝土配合比设计%Mix Proportion Design of High-performance Concrete for Traffic Bridges in South-to-north Water Diversion

    Institute of Scientific and Technical Information of China (English)

    彭辉; 谭健波

    2011-01-01

    结合南水北调中线鹤壁段C50F200混凝土配合比设计实例,介绍了在寒冷地区桥梁高性能混凝土配合比设计的全过程,通过合理选择原材料,选用高性能减水剂,确定经济适用的配合比.实际工程应用效果证明,所配制的C50F200混凝土完全满足施工要求,效果明显.%Based on mix proportion design of high-performance concrete in Hebi segment of South-to-north Water Diversion, authors describe the whole design process of mix proportion for concrete in cold regions bridge. Through a reasonable selection of raw materials and high-performance additives, the economical and appropriate mix proportion is decided. The application of practical engineering proves that the C50F200 concrete can fully meet the construction requirements, and the application effect is obvious.

  9. Revised Rules for Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Jensen, F. M.; Middleton, C.;

    This paper is based on research performed for the Highway Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: Concrete Bridges" It contains details of a methodology which can be used to generate Whole Life (WL) reliability profiles....... These WL reliability profiles may be used to establish revised rules for Concrete Bridges....

  10. The calculation of noise from railway bridges and viaducts

    OpenAIRE

    Bewes, Oliver Guy

    2005-01-01

    Pandrol Rail Fastenings Limited are a designer and manufacturer of railway rail-fastening systems. As an organisation they have the capability to reduce the noise impact of bridges using resilient track components. They also have a commercial interest in providing such technology. Knowledge of the processes behind bridge noise is important to Pandrol in two ways; to aid the engineers within the organisation in the design of fastening systems and to demonstrate a state-of-the-ar...

  11. Numerical analysis of dynamic response of vehicle–bridge coupled system on long-span continuous girder bridge

    Directory of Open Access Journals (Sweden)

    Lipeng An

    2016-07-01

    Full Text Available To systematically study the vehicle–bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle space vibration system was deduced. Considering the stimulation of road roughness, the dynamic response equation of vehicle–bridge coupled system was established in accordance with the elastic system principle of total potential energy with stationary value and the “set-in-right-position” rule. On the basis of the self-compiled Fortran program and bridge engineering, the dynamic response of long-span continuous girder bridge under vehicle load was studied. This study also included the calculation of vehicle impact coefficient, evaluation of vibration comfort, and analysis of dynamic response parameters. Results show the impact coefficient changes with lane number and is larger than the value calculated by the “general code for design of highway bridges and culverts (China”. The Dieckmann index of bridge vibration is also related to lane number, and the vibration comfort evaluation is good in normal conditions. The relevant conclusions from parametric analyses have practical significance to dynamic design and daily operation of long-span continuous girder bridges in expressways. Safety and comfort are expected to improve significantly with further control of the vibration of vehicle–bridge system.

  12. Dynamic Bridge Response for a Bridge-friendly Truck

    Directory of Open Access Journals (Sweden)

    V. Šmilauer

    2004-01-01

    Full Text Available A truck with controlled semi-active suspensions traversing a bridge is examined for benefits to the bridge structure. The original concept of a road-friendly truck was extended to a bridge-friendly vehicle, using the same optimization tools. A half-car model with two independently driven axles is coupled with simply supported bridges (beam, slab model with the span range from 5 m to 50 m. Surface profile of the bridge deck is either stochastic or in the shape of a bump or a pot in the mid-span. Numerical integration in the MATLAB/SIMULINK environment solves coupled dynamic equations of motion with optimized truck suspensions. The rear axle generates the prevailing load and to a great extent determines the bridge response. A significant decrease in contact road-tire forces is observed and the mid-span bridge deflections are on average smaller, when compared to commercial passive suspensions. 

  13. Case Study on 4000 m-span Cable-stayed Suspension Bridge

    Directory of Open Access Journals (Sweden)

    Haijun Wang

    2014-04-01

    Full Text Available This study describes the case studies for a cable-stayed suspension bridges proposed over the Tsugaru Strait, Japan. Center Bridge is designed as a compound bridge of suspension bridges and cable-stayed bridges with 4000 m super-long-span. Case studies about the effects of cable-stayed bridge length, the design of sub-cable, height and stiffness of main tower, type of foundation and length of side span on displacement were carried out. With appropriate design of above parameters, the compound bridge can reduce horizontal displacement of main tower and vertical deflection in the central portion and enhance resistance to partial loading. The study reports the results based on these case studies.

  14. Application Study on HEC-RAS Three-dimensional River Hydraulic Calculation and Analysis System for Bridge Design Optimization%HEC RAS三维河道水力分析计算系统在桥梁优化设计的应用研究

    Institute of Scientific and Technical Information of China (English)

    杨磊磊

    2014-01-01

    Based on computational fluid dynamics, and using three-dimensional river hydraulic model HEC-RAS ( River Analyse System) , this paper took the interchange bridge No. 2 as the research object, which is situated on the Bejaia Express Highway in Algeria and was still under construction. Meanwhile, under the same geological condition and with once-in-a-hundred-year flood peak flow, the paper analyzed the influences of different bridge span schemes on the maximum bridge scouring depth. And then in this paper, the calculation results of three-dimensional river hydraulic model under the condition of different bridge span schemes were analyzed and researched, and finally an economical and reasonable bridge design scheme was determined. This paper provides a new research approach of scheme design for similar bridges at home and abroad in future.%基于计算流体动力学的方法,运用三维河道水力学模型HEC-RAS( River Analyse System)分析阿尔及利贝贾亚高速公路在建项目2号互通桥梁在百年一遇的最大洪峰流量下,不同桥梁孔跨方案在相同地质条件下对桥梁最大冲刷深度的影响,对不同桥梁孔跨方案下三维河道水力学模型计算结果进行分析研究,确定经济合理的桥梁设计方案,为今后国内外同类桥梁设计的方案研究提供了新的研究方法。

  15. 一人桥楼窗框节点解决方案%Window Frame Design of Wheel House for One-man Bridge

    Institute of Scientific and Technical Information of China (English)

    徐美芳

    2014-01-01

    The arrangement of wheel house doors and windows for one-man control console was always difficult for the outfitting designer,due to fact that designers from structure and outfitting discipline did not know each other’s disciplines. The paper connected two disciplines to search for the solution. The structure detail was designed especially in order to fulfill the class requirements as much as possible. The article introduced detail design of wheelhouse doors and windows arrangement improvement based on a 400K VLOC ,which fulfill the NAUT-OC requirements. Four solutions for the structure of window ’s frame were demonstrated which could serve as reference.%一人桥楼门窗布置的设计一直以来是舾装设计的难点。追究其原因,主要是舾装和结构对相互的专业细节不甚了解。现将这两专业进行结合探索其解决方案,同时对结构细节进行专门设计以最大限度地满足规范规则对桥楼视线的要求。描述了40万t船满足NAUT-OC要求的驾驶室窗框节点设计的改进,同时着重总结一人桥楼窗框节点的设计及优化,列出四种驾驶室窗框节点方案,供同行参考讨论。

  16. 虎门二桥62.5 m跨预制节段拼装PC连续刚构桥上部结构设计%Humen Bridge across 62 .5 m Segmental PC continuous rigid frame bridge design department

    Institute of Scientific and Technical Information of China (English)

    刘海龙; 徐德志

    2015-01-01

    虎门二桥部分引桥采用了62.5 m跨预制节段拼装PC连续刚构桥的结构形式,该桥纵向预应力体系为体内束加体外束。介绍了该桥上部结构的结构尺寸、节段拼装构造形式、预应力形式和节段黏结接缝构造。并采用MIDAS CIVIL 2012专业桥梁分析软件建立全桥三维空间杆系模型,对结构进行计算,结果表明结构的应力、强度均满足规范要求。%Humen Bridge Approach uses a 62.5 m section across Segmental PC continuous rigid frame structure of the bridge, the bridge longitudinal beams prestressed system plus external beam vivo.Describes the structure size of the bridge superstructure is constructed in the form of Segmental Prestressed form and segmental construction adhesive joints.And u-sing MIDAS CIVIL 2012 professional analysis software to build a bridge full bridge three-dimensional space truss model of the structure, and the results show that stress, strength of the structure meet the specification requirements.

  17. Study on longitudinal wind load calculation method of cables for cable-stayed bridge

    Institute of Scientific and Technical Information of China (English)

    Pei Minshan; Zhang Xigang; Zhu Bin; Hou Bin; Liu Changpeng

    2009-01-01

    Along with the expanding of span of cable-stayed bridge, wind load becomes a more and more important controlling factor for bridge the design. A very large proportion of the wind load acting on cables has exceeded that acting on deck. There was not any detailed prescript in Chinese code for calculation of longitudinal wind load on cables due to lack of theoretical research and experiment, and conservative simplified calculation was adopted during design, which leads to conservative and uneconomical design of structures. To resolve this problem, cable force experiment was carried out during the design of Sutong Bridge. By comparing with international research results, the calculation formula of longitudinal wind drag coefficient for cables was advanced to fill the blank of bridge wind resistant code of China, and has already been adopted in the Highway Bridge Wind Resistant Design Code (JTG/T D60-01-2004) with great significance for bridge engineering.

  18. Dynamic Analysis of A Pontoon-Separated Floating Bridge ubjected to A Moving Load

    Institute of Scientific and Technical Information of China (English)

    WANG Cong; FU Shi-xiao; LI Ning; CUI Wei-cheng; LIN Zhu-ming

    2006-01-01

    For the design and operation of a floating bridge, the understanding of its dynamic behavior under a moving load is of great importance. The purpose of this paper is to investigate the dynamic performances of a new type floating bridge, the pontoon-separated floating bridge, under the effect of a moving load. In the paper, a brief summary of the dynamic analysis of the floating bridge is first introduced. The motion equations for a pontoon-separated floating bridge, considering the nonlinear properties of connectors and vehicles' inertia effects, are proposed. The super-element method is applied to reduce the numerical analysis scale to solve the reduced equations. Based on the static analysis, the dynamic features of the new type floating bridge subjected to a moving load are investigated. It is found that the dynamic behavior of the pontoon-separated floating bridge is superior to that of the ribbon bridge by taking the nonlinearity of connectors into account.

  19. ANALYTICAL MODELS OF FLOATING BRIDGES SUBJECTED BY MOVING LOADS FOR DIFFERENT WATER DEPTHS

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jun; MIAO Guo-ping; LIU Jian-xun; SUN Wen-jun

    2008-01-01

    There are two types of floating bridge such as discrete-pontoon floating bridges and continuous-pontoon floating bridges.Analytical models of both floating bridges subjected by moving loads are presented to study the dynamic responses with hydrodynamic influence coefficients for different water depths. The beam theory and potential theory are introduced to produce themodels. The hydrodynamic coefficients and dynamic responses of bridges are evaluated by the boundary element method and by the Galerkin method of weighted residuals, respectively. Considering causal relationship between the frequencies of the oscillation of floating bridges and the added mass coefficients, an iteration method is introduced to compute hydrodynamic frequencies. The results indicate that water depth has little influence upon the dynamic responses of both types of floating bridges, so that the effect of water depth can be neglected during the course of designing floating bridges.

  20. 高速铁路桥梁支座设计要求及应用技术%Application Technology and Design Requirement of High Speed Railway Bridge Bearing

    Institute of Scientific and Technical Information of China (English)

    王旭芳

    2011-01-01

    To meet the requirements of large bearing capacity and displacement of long-span bridge for high speed rail- way, the bearings shall have such performances as large tonnage, large displacement as well as anti-vibration in some level. However, due to limit of allowable design stress of material, the bearing with large tonnage is too big to change during operation, so the design of it shall take full consideration of structural durability. Meanwhile, the control of post- construction settlement is especially rigorous in high speed railway, the height-adjustable bearings may be adopted at some special section. This paper presents some design requirements of high speed railway bearings, briefs its installation technology and provides advice for its application.%为满足高速铁路大跨度桥梁的大承载力和大位移的需要,要求支座具有大吨位大位移性能,同时还具有一定的减隔振性能。受材料设计容许应力的限制,大吨位支座的尺寸较大,不适宜运营期的更换,因此,支座设计时应充分考虑结构的耐久性。高速铁路对工后沉降量控制严格,在一些特殊地段还需采用可调高支座进行调整。文章对高速铁路支座的设计要求做了一些展述,并对高速铁路支座安装技术做了介绍。

  1. 半桥型LLC变换器稳态建模与参数设计%Model and parameter design of half bridge LLC converter

    Institute of Scientific and Technical Information of China (English)

    李尹泉; 尹斌; 康亚东

    2014-01-01

    本文介绍了LLC型谐振变换器的主电路结构和工作原理。通过基波分析法对半桥型LLC谐振变换器进行稳态建模分析,得出了谐振腔的等效电路和直流增益表达式。基于稳态模型的基础上,给出了半桥型LLC谐振电容、谐振电感和励磁电感的设计方法。最后通过saber仿真验证了半桥型LLC谐振变换器稳态模型与参数设计方法的正确性。%This paper introduces the main circuit structure and working principle of LLC resonant converter. Through the analysis of steady state model of LLC resonant converter, based on FHA, equivalent circuit of resonant cavity and DC gain expressions are obtained. Based on the steady-state model, the design method of LLC resonant capacitance, inductance and excitation inductance are given. The accuracy of the steady-state model and the design method of parameters are proved by saber simulation.

  2. BRIDGING SERVICE QUALITY GAPS

    OpenAIRE

    BARKATH UNISSA

    2012-01-01

    Bridging the Service quality gaps is one of the foremost areas of concern for amarketer. Service marketing is inherently different from product or goods marketing.Services are distinctively characterized by their intangible, heterogeneous, inseparableand perishable nature. The importance of the service sector in today's world is a verywidely accepted and renowned idea. “We are already experiencing a service society“services do have some basic characteristics which make them fundamentally diff...

  3. Bridging as Coercive Accommodation

    CERN Document Server

    Bos, J W; Mineur, A M; Bos, Johan; Buitelaar, Paul; Mineur, Anne-Marie

    1995-01-01

    In this paper we discuss the notion of "bridging" in Discourse Representation Theory as a tool to account for discourse referents that have only been established implicitly, through the lexical semantics of other referents. In doing so, we use ideas from Generative Lexicon theory, to introduce antecedents for anaphoric expressions that cannot be "linked" to a proper antecedent, but that do not need to be "accommodated" because they have some connection to the network of discourse referents that is already established.

  4. Nematic liquid crystal bridges

    Science.gov (United States)

    Doss, Susannah; Ellis, Perry; Vallamkondu, Jayalakshmi; Danemiller, Edward; Vernon, Mark; Fernandez-Nieves, Alberto

    We study the effects of confining a nematic liquid crystal between two parallel glass plates with homeotropic boundary conditions for the director at all bounding surfaces. We find that the free surface of the nematic bridge is a surface of constant mean curvature. In addition, by changing the distance between the plates and the contact angle with the glass plates, we transition between loops and hedgehogs that can be either radial or hyperbolic.

  5. Isolated Full Bridge Boost DC-DC Converter Designed for Bidirectional Operation of Fuel Cells/Electrolyzer Cells in Grid-Tie Applications

    DEFF Research Database (Denmark)

    Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.

    2013-01-01

    -dc converter (IFBBC) designed for this new application focusing on losses analysis. The system topology is briefly discussed and the major concerns related to the system, cells stacks and converter operating points are analyzed. The dc-dc converter losses are modeled and presented in detail; the analysis...... is validated on adc-dc converter prototype rated at 6 kW 30-80 V 0-80 A on the low voltage side and 700-800 V on the high voltage side (for a grid-tie application). The prototype is based on fully planar magnetic, Si MOSFETs, Si IGBTs and SiC diodes; efficiencies up to ~96.5% and ~97.8% were demonstrated...

  6. Blueprint and First Experiences Bridging Hardware Virtualization and Global Grids for Advanced Scientific Computing: Designing and Building a Global Edge Services Framework (ESF) for OSG, EGEE, and LCG

    CERN Document Server

    Rana, A S; Vaniachine, A; Wurthwein, F; Foster, I; Sotomayor, B; Freeman, T

    2006-01-01

    We report on first experiences with building and operating an edge services framework (ESF) based on Xen virtual machines instantiated via the workspace service in Globus toolkit, and developed as a joint project between EGEE, LCG, and OSG. Many computing facilities are architected with their compute and storage clusters behind firewalls. Edge services (ES) are instantiated on a small set of gateways to provide access to these clusters via standard grid interfaces. Experience on EGEE, LCG, and OSG has shown that at least two issues are of critical importance when designing an infrastructure in support of ES. The first concerns ES configuration. It is impractical to assume that each virtual organization (VO) using a facility will employ the same ES configuration, or that different configurations will coexist easily. Even within a VO, it should be possible to run different versions of the same ES simultaneously. The second issue concerns resource allocation: it is essential that an ESF be able to effectively gu...

  7. Anti-wave Design for Independent Drilling Platform of Sea-crossing Bridge in the Typhoon Area%台风区跨海桥梁独立钻孔平台抗风浪设计

    Institute of Scientific and Technical Information of China (English)

    范发财

    2016-01-01

    In connection with the (B0 ~B58)main pier foundation independent drilling platform of the highway and rail-way combined bridge over the Pingtan Strait of newly-built Fuzhou-Pingtan Railway under the complicated typhoon area sea conditions such as strong wind,high wave and urgent flow,we carry out a summary respectively from the aspects of the structure comparison of independent platform,the structure design calculation for drilling platform and its structural analysis during construction.It can provide a reference for similar engineering construction in future.%针对新建福州至平潭铁路平潭海峡公铁两用大桥(B0~B58)主墩基础独立钻孔平台所处风大、浪高、流急等复杂台风区海况下,分别从独立平台结构形式的比选,钻孔平台的结构设计检算以及施工过程中结构分析等方面进行了总结,为以后类似工程施工提供借鉴。

  8. 基于行为心理的重庆市观音桥步行街坐具设计策略研究%On Behavior Psychology-Based Design Strategy of Guanyin Bridge Pedestrian Street Seat

    Institute of Scientific and Technical Information of China (English)

    黄友慧; 辛儒鸿; 周建华

    2015-01-01

    Based on the theory of behavior and psychology ,the present situation of Guanyin bridge pedes‐trian street in Chongqing has been investigated and analyzed with the method of field observation and ques‐tionnaires .Besides this paper puts forward some suggestions for improvement ,then summarizes the design strategies of commercial pedestrian street seat ,from the aspects of function ,layout ,the form and the o‐verall environment to meet the needs of people .%以行为心理学为理论基础,采用实地观察和调查问卷的方式,调查分析了重庆市观音桥步行街坐具的使用现状,并提出一定的改进建议,进而总结出从功能、布局、形式及整体环境等方面满足人的需求的商业步行街坐具的设计策略。

  9. 厦漳跨海大桥海工高性能混凝土配制技术%Mix Design Technology of Marine Concrete with High Performance of Xiamen-Zhangzhou Sea-crossing Bridge

    Institute of Scientific and Technical Information of China (English)

    焦运攀; 秦明强; 屠柳青; 张明雷; 陈杰

    2011-01-01

    Marine concrete mix proportion design, the optimization of materials and the selection of key parameters are introduced. Then NT Build 492 standard is used to get the index of resistance to chloride ion permeability. The requirement of concrete crack resistance is put forward finally. Based on the example of marine high performance concrete of Xiamen-Zhangzhou Sea-crossing Bridge,a series of tests about marine concrete are done. The application of in-situ concrete construction shows that the workability, mechanical performance and the resistance to chloride ion permeability of concrete are excellent ,and the concrete can meet construction requirements.%介绍了海工混凝土配合比设计原则、原材料优选和关键参数的确定等,选用NT Build 492标准确定抗氯离子渗透性指标,最后提出混凝土抗裂性控制要求.将以上原理应用于厦漳跨海大桥海工高性能混凝土实际工程中,从现场混凝土应用情况看,混凝土配合比工作性、力学性能、耐久性和抗氯离子渗透性良好,满足施工需要.

  10. Design of Static Transfer Switch for Ship Based on LC Bridge-Type Convertor Circuit%基于LC桥式换流的船用静态切换开关设计

    Institute of Scientific and Technical Information of China (English)

    陈海涛; 刘正海; 杨峰权; 祝义华; 童敏杰; 周凯; 林录云

    2015-01-01

    In order to meet severe requirements of ship for power quality, static transfer switch (STS) is a dual power switching system. STS mainly contains the LC bridge-type auxiliary resonant convertor circuit, the circuit of digital trigger and the control circuit of DSP. This paper puts forward a new LC bridge-type auxiliary convertor circuit. To prevent the injection of remaining power on resonant bypass into the load, the main SCR is used to absorb excess power on the resonant capacitor, and without using serial feedback diode, the feedback of power can be executed which reduces the power consumption. In order to avoid the rapid rise in the resonant current, a proper power resistor is added between capacitor and inductor on the resonant bypass of the circuit. A large number of experiments show that the design can complete the switch within 8 ms and it can be up to a continuous power supply requirements.%为了满足船舶设备对供电质量的苛刻要求,研发设计了一种针对双路电源切换的船用静态切换开关系统.静态切换开关装置由LC谐振换电流模块、数字触发模块、DSP数字控制系统模块等组成.设计了一套全新的LC桥式谐振辅助换电流电路,为了避免谐振旁路上的多余电量流入负载,利用主用晶闸管吸收多余电量,同时不必串联反馈二极管但是却又能达到馈能的效果,降低了系统的功耗;为了避免谐振电流急速上升,将一个适当阻值的功率电阻串联在谐振旁路电容与电感之间.通过大量的实验证明,系统切换工作完全可以控制在8 ms以内,完成了连续供电的要求.

  11. BRIDGING THE GAP OF INDIAN REGULATIONS AND MAJOR GLOBAL REGULATIONS FOR BIOEQUIVALENCE STUDIES WITH EMPHASIS ON ADAPTIVE SEQUENTIAL DESIGN AND TWO-STAGE BIOEQUIVALENCE STUDIES

    Directory of Open Access Journals (Sweden)

    Shah Kalpesh

    2013-04-01

    Full Text Available The cost of healthcare has been escalating globally during the last two decades, and this has prompted efforts in most countries to reduce those costs. Because of the importance of generic drugs in healthcare, it is imperative that the pharmaceutical quality and in vivo performance of generic drugs be reliably assessed. Because generic drugs would be interchanged with innovator products in the market place, it must be demonstrated that the safety and efficacy of generics are comparable to the safety and efficacy of the corresponding innovator drugs. The concept of bioavailability (BA and bioequivalence (BE has been accepted worldwide by the pharmaceutical industry and national regulatory authorities for over 20 years and is applied to new as well as generic products. As a result, thousands of high-quality generic drugs at reduced costs have become available in every corner of the globe. The assessment of BE is not a simple issue, however, and much of the research has been done in recent years to develop new and more effective approaches to the assessment of BE. There are several approaches to assess BE and each regulatory authority has its own regulations/guidance for conducting BA/BE studies before approving generic products for marketing in their country. Therefore, a thorough understanding is required of these BA/BE concepts and basic regulatory requirements for conduct of BA/BE studies. In this article, the regulatory guidelines are compared on the basis of various parameters involving the clinical conduct of the BA/BE studies. Harmonization of these approaches may decrease the number of in vivo bioequivalence studies and avoid unnecessary drug exposure to humans. Another upcoming approach for conduct of bioequivalence studies is Adaptive design, which is a relatively new approach. This innovation is becoming accepted by the regulators and has been taken up by the pharmaceutical industry to reduce product development times and costs. There

  12. Impact Coefficient Analysis of Long-Span Railway Cable-Stayed Bridge Based on Coupled Vehicle-Bridge Vibration

    Directory of Open Access Journals (Sweden)

    Yongle Li

    2015-01-01

    Full Text Available Compared with medium and small span bridges, very limited attention has been paid on the research of the impact coefficient of long-span railway bridges. To estimate the impact effects of long-span railway bridges subjected to moving vehicles, a real long-span railway cable-stayed bridge is regarded as the research object in this study, and a coupled model of vehicle-bridge system is established. The track irregularities are taken as the system excitation and the dynamic responses of the vehicle-bridge system are calculated. The impact effects on main girder, stayed cable, bearings, and bridge tower are discussed at various vehicle speeds. The results show that different components of the long-span railway cable-stayed bridge have different impact coefficients. Even for each part, the impact coefficient is also different at different local positions. It reveals that the impact coefficients in the actual situation may have significant differences with the related code clauses in the present design codes.

  13. Effect of near-fault earthquake on bridges: lessons learned from Chi-Chi earthquake

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The objective of this paper is to describe the lessons learned and actions that have been taken related to the seismicdesign of bridge structures after the Chi-Chi, Taiwan earthquake. Much variable near-fault ground motion data was collected fromthe rupture of Chelungpu fault during the Chi-Chi earthquake, allowing the seismic response of bridge structures subjected to thesenear-fault ground motions to be carefully examined. To study the near-fault ground motion effect on bridge seismic design codes, atwo-level seismic design of bridge structures was developed and implemented. This design code reflects the near-fault factors in theseismic design forces. Finally, a risk assessment methodology, based on bridge vulnerability, is also developed to assist in decisionsfor reducing seismic risk due to failure of bridges.

  14. On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments

    Science.gov (United States)

    Prasai, Binay; Wilson, A. R.; Wiley, B. J.; Ren, Y.; Petkov, Valeri

    2015-10-01

    The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.The extent to which current theoretical modeling alone can

  15. On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments.

    Science.gov (United States)

    Prasai, Binay; Wilson, A R; Wiley, B J; Ren, Y; Petkov, Valeri

    2015-11-14

    The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au(100-x)Pd(x) (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when "tuned up" against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design. PMID:26463562

  16. Multiobjective Optimal Control of Longitudinal Seismic Response of a Multitower Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Geng Fangfang

    2016-01-01

    Full Text Available The dynamic behavior of a multitower cable-stayed bridge with the application of partially longitudinal constraint system using viscous fluid dampers under real earthquake ground motions is presented. The study is based on the dynamic finite element model of the Jiashao Bridge, a six-tower cable-stayed bridge in China. The prime aim of the study is to investigate the effectiveness of viscous fluid dampers on the longitudinal seismic responses of the bridge and put forth a multiobjective optimization design method to determine the optimized parameters of the viscous fluid dampers. The results of the investigations show that the control objective of the multitower cable-stayed bridge with the partially longitudinal constraint system is to yield maximum reductions in the base forces of bridge towers longitudinally restricted with the bridge deck, with slight increases in the base forces of bridge towers longitudinally unrestricted with the bridge deck. To this end, a multiobjective optimization design method that uses a nondominating sort genetic algorithm II (NSGA-II is used to optimize parameters of the viscous fluid dampers. The effectiveness of the proposed optimization design method is demonstrated for the multitower cable-stayed bridge with the partially longitudinal constraint system, which reveals that a design engineer can choose a set of proper parameters of the viscous fluid dampers from Pareto optimal fronts that can satisfy the desired performance requirements.

  17. Theory of bridge aerodynamics

    CERN Document Server

    Strømmen, Einar

    2006-01-01

    This text book is intended for studies in wind engineering, with focus on the stochastic theory of wind induced dynamic response calculations for slender bridges or other line ?like civil engineering type of structures. It contains the background assumptions and hypothesis as well as the development of the computational theory that is necessary for the prediction of wind induced fluctuating displacements and cross sectional forces. The simple cases of static and quasi-static structural response calculations are for the sake of completeness also included. The text is at an advanced level in the

  18. Seismic vulnerability of historical arch type bridge structures in Italy

    OpenAIRE

    Qadir Bhatti, Abdul

    2009-01-01

    Italy is located on a earthquake prone area and old bridges were desinged without any seismic provision. In the years (2009), tremors were felt in Italy due to the strong earthquakes at Abruzzo, which highlight the earthquake threat to Italy. This study focuses on seismic vulnerability of arch type masonry bridge structures in Italy, designed primarily for gravity loads, when they are subjected to earthquakes. A case study has been carried out for the vulnerability study for a ...

  19. A Unique Prestressed Concrete Pedestrian Bridge in Spain

    OpenAIRE

    Ivorra Chorro, Salvador; Alvado Bañón, Joaquín; Crespo Zaragoza, Miguel Ángel

    2014-01-01

    This paper describes the so-called Kiss Bridge. This structure resembles a kiss, a subtle touch of structures. The beams have been structurally designed to adapt the Japanese art of paper folding called "origami." The material used for constructing the floating beams is white reinforced concrete in the form of folded shells. The two geometrically different parts have distinct structural behaviors. The length of the main pathway of both structures is over 60 m. The pedestrian bridge crosses an...

  20. Optimization of Dead Load State in Earth-Anchored Cable-Stayed Bridges

    Institute of Scientific and Technical Information of China (English)

    Bin Sun∗; Rucheng Xiao

    2015-01-01

    In order to determine the reasonable completed dead load state in earth⁃anchored cable⁃stayed bridges, a practical method is proposed. The method is based on the rigidly supported continuous beam method and the feasible zone method, emphasizing on the mutual effect between the self⁃anchored structural parts and the earth⁃anchored ones. Three cable⁃stayed bridge models are designed with the main spans of 1 400 m, including a partially earth⁃anchored cable⁃stayed bridge, a cable⁃stayed⁃suspension bridge and a fully self⁃anchored cable⁃stayed bridge, in which the C50 concrete and Q345 steel are adopted. The partially earth⁃anchored cable⁃stayed bridge and the cable⁃stayed⁃suspension bridge secure lower compressive force in the girder than the fully self⁃anchored cable⁃stayed bridge by 25 percent at least. The same is for the material consumption of the whole bridge. Furthermore, the anchor volume is more than 20% lower in the partially earth⁃anchored cable⁃stayed bridge than that in the cable⁃stayed⁃suspension bridge. Consequently, the practical span of cable⁃stayed bridges can be accordingly extended.

  1. Translating Climate Projections for Bridge Engineering

    Science.gov (United States)

    Anderson, C.; Takle, E. S.; Krajewski, W.; Mantilla, R.; Quintero, F.

    2015-12-01

    A bridge vulnerability pilot study was conducted by Iowa Department of Transportation (IADOT) as one of nineteen pilots supported by the Federal Highway Administration Climate Change Resilience Pilots. Our pilot study team consisted of the IADOT senior bridge engineer who is the preliminary design section leader as well as climate and hydrological scientists. The pilot project culminated in a visual graphic designed by the bridge engineer (Figure 1), and an evaluation framework for bridge engineering design. The framework has four stages. The first two stages evaluate the spatial and temporal resolution needed in climate projection data in order to be suitable for input to a hydrology model. The framework separates streamflow simulation error into errors from the streamflow model and from the coarseness of input weather data series. In the final two stages, the framework evaluates credibility of climate projection streamflow simulations. Using an empirically downscaled data set, projection streamflow is generated. Error is computed in two time frames: the training period of the empirical downscaling methodology, and an out-of-sample period. If large errors in projection streamflow were observed during the training period, it would indicate low accuracy and, therefore, low credibility. If large errors in streamflow were observed during the out-of-sample period, it would mean the approach may not include some causes of change and, therefore, the climate projections would have limited credibility for setting expectations for changes. We address uncertainty with confidence intervals on quantiles of streamflow discharge. The results show the 95% confidence intervals have significant overlap. Nevertheless, the use of confidence intervals enabled engineering judgement. In our discussions, we noted the consistency in direction of change across basins, though the flood mechanism was different across basins, and the high bound of bridge lifetime period quantiles exceeded

  2. 一种使用H桥和多谐振荡器的无线充电器设计%A Design of Wireless Charger based on H-Bridge and Multivibrator

    Institute of Scientific and Technical Information of China (English)

    耿其炜; 宋宇飞; 陈耀

    2014-01-01

    针对有线充电繁琐的人工操作和线材杂乱的弊端,设计一种无线充电器方案。此设计使用H桥逆变器和基于NE555的多谐振荡器,利用开关电源模块对交流电进行降压和整流,再将直流电逆变为交流电并通过线圈将电能发射,接收端将接收到的交流电能整流滤波后稳压供应给用电器。与大多数一对一无线充电方案相比,本设计可以在一较大范围内对多个移动设备同时供电。该套系统经测试可稳定工作,并可同时给手机、键盘和鼠标三件无线设备供电,达到设计要求。%To avoid tedious manual charging cable and wire clutter drawbacks,this paper develops a scheme for designing a wireless charger by using an H-bridge inverter and a multivibrator based on NE555.Then switch power module is applied to reduce the voltage and rectify the alternating current.Next,direct current is inverted to alternating current,and the power is transmitted via coils.The alternating power,which is filtered and rectified,is provided for electrical appliances. Compared with the mostly used one-to-one wireless chargers,this design is able to simultaneously power multiple mobile devices in a large area.The tests suggest that this system can work stably and charge mobile phone,keyboard and mouse at the same time.The design purpose is achieved.

  3. Design of Bridge-Detection Vehicle Monitoring System Based on Android%基于Android的桥梁检测车安全监控系统的设计

    Institute of Scientific and Technical Information of China (English)

    张麒; 王秀敏; 任建新

    2012-01-01

    为解决国内桥梁检测车全局监控设备以及碰撞警报设备缺乏的问题,设计并实现了基于Android平台的一套智能监控系统.该系统通过倾角传感器采集的数据,用3D模型实时模拟机械臂的姿态,以达到全局监控的目的.同时可以根据实际情况构建虚拟障碍物,实现机械臂与障碍物碰撞的逼真模拟与警报.结果表明,该系统性能可靠、实用性强,不但解决了传统视频监控无法达到全局监控的问题,还对人工规避障碍物提供了可靠的参考.%To solve the problem of lacking of global monitoring device and collision warning device for domestic bridge-detection vehicle,we design and implement an intelligent monitoring system based on Android. The system uses real-time 3D model to simulate robot arm posture in realtime from tilt sensor, a-chieving global monitoring. The system can also build virtual obstacles based on actual situation,to simulate the collision between robot arm and obstacles vividly. If collision was detected,the system will trigger the alarm. Result shows that the system has reliable performance as well as strong practicability, it not only solve the problems of the traditional video surveillance can not reach the global monitoring, and also provides a reliable reference for avoiding obstacles by labour.

  4. Evaluation of Seismic Performance of Long Span Continuous Girder Bridges Based on Seismic Isolation Design%基于减隔震设计的大跨度连续梁桥抗震性能评价

    Institute of Scientific and Technical Information of China (English)

    李贞新; 刘高

    2011-01-01

    Nonlinear time history analysis method is adopted to analyze dynamic characteristics and seismic performance based on long span continuous girder bridges with spans of 89 m, 170 m and 89 m in high intensity region. The good hysteretic, energy-dissipation characteristics and self-restoring ability of double curvature seismic isolation bearings are simulated as well as the friction energy-dissipation characteristics of sliding bearing and damping energy-dissipation characteristics of dampers. Analytical results indicate that seismic performance can basically meet the expected design goal; seismic isolation device of double curvature spherical supports and dampers can adjust dynamic characteristics, reduce seismic response, dissipate earthquake energy and guarantee the safety of the structure.%基于高烈度区的某大跨度连续梁桥(89 m+170 m+89 m),采用非线性时程分析法进行结构动力特性及抗震性能分析.全桥均采用三维梁单元建立空间模型,对于双曲面球形减隔震支座的滞回耗能特性和自恢复功能,活动支座的摩擦耗能以及固定销剪断后的效应进行了模拟,同时模拟了阻尼器的阻尼耗能作用.研究结果表明:采用双曲面球形减隔震支座及桥台处纵向阻尼器后,结构的反应得到了很好的控制,确保了高烈度区结构的抗震安全性.

  5. 武汉天兴洲公铁两用桥主塔爬模设计及应用%Design and Application of Climbing Slipform Formwork in Pylon Tower of Wuhan Tianxingzhou Yangtze River Highway-railway Bridge

    Institute of Scientific and Technical Information of China (English)

    宁智刚

    2011-01-01

    武汉天兴洲公铁两用桥主塔模板施工采用液压自爬模体系,打破了传统的施工工艺,对施工环境、提高施工工效、安全环保等都有所改善.针对该工程主塔模板施工,施工脚手架采用液压自爬模系统配合木工字梁模板体系,并对爬模体系进行了优化和设计.此外,阐述了模板系统组成及液压自爬架组成,详细介绍了爬模施工方案以及安全规定.体现了液压自爬模及木梁胶合板模板体系用于异型混凝土结构的优越性.%Hydraulic climbing slipform system is used with main tower formwork construction of Wuhan Tianxingzhou Yangtze river highway-railway bridge, the traditional construction technology is changed. The construction environment, construction efficiency, safety and environmental protection is all improved. Based on the construction, construction scaffolding is used with hydraulic climbing slipform system combined with wood H beam formwork system, and auto-climbing formwork system is optimized and designed. In addition, formwork system composition and hydraulic climbing slipform system are expounded. Construction scheme of climbing slipform and safety regulations are introduced in detail. The fact shows that it is reasonable that hydraulic climbing slipform system and timber beam plywood formwork system are used in non-standard concrete structure.

  6. 基于力学与造价的CFRP-钢组合拉索斜拉桥设计理论%Design of Cable-stayed Bridges with CFRP-steel Composite Stay Cables Based on Mechanical and Economical Behaviors

    Institute of Scientific and Technical Information of China (English)

    熊文; 肖汝诚; CAIC S; 叶见曙

    2012-01-01

    To solve the problem resulting from the low structural stiffness, authors proposed a new design of cable-stayed bridges with composite carbon fiber reinforced polymer (CFRP)-steel stay cables, especially for the cable-stayed bridges with main spans of 1 400 ~ 2 800 m. More specifically, the CFRP stay cables with high strength-to-weight ratio and traditional steel stay cables with high elastic modulus were combined together for application in cable-stayed bridges, which could improve the entire stiffness of bridges. Through a parametric study concerning the equivalent stiffness and economical behavior, three design strategies for the composite cable- stayed bridges were proposed in details: the best equivalent stiffness with equal safety factor, best equivalent stiffness-to-cost ratio with equal safety factor and best equivalent stiffness with equal budget. The design procedure and design chart based on the proposed strategies were also provided. Finally, the feasibility of the proposed cable-stayed bridges was discussed through a case study of a cable-stayed bridge with a main span of 1 400 m. The results indicate that the proposed composite cable-stayed bridges can demonstrate a high equivalent stiffness and can be an excellent selection for the bridges with main spans of 1 400~2 800 m.%针对1400~2800m主跨斜拉桥整体刚度不足的问题,提出一种新型结构方案——碳纤维增强塑料(CFRP)-钢组合拉索斜拉桥。该方案将CFRP斜拉索与传统钢斜拉索同时应用于斜拉桥中,组合2种材料高强轻质及弹性模量高的优点,以:达.到提高斜拉桥整体刚度的设计目的。通过基于力学与造价的参数分析提出该组合拉索斜拉桥的3种设计原则:等安全系数等效刚度最优、等安全系数等效刚度性价比最优、等造价等效刚度最优,并分别给出详细的设计步骤及设计用图。最后,进行了多种方案1400m主跨斜拉桥试设计。结果

  7. Bridge Pressure Flow Scour at Clear Water Threshold Condition

    Institute of Scientific and Technical Information of China (English)

    GUO Junke; KERENYI Kornel; PAGAN-ORTIZ Jorge E; FLORA Kevin

    2009-01-01

    Bridge pressure flow scour at clear water threshold condition is studied theoretically and experimentally. The flume experiments reveal that the measured scour profiles under a bridge are more or less 2-dimensional; all the measured scour profiles can be described by two similarity equations, where the horizontal distance is scaled by the deck width while the local scour by the maximum scour depth; the maximum scour position is located just under the bridge about 15% deck width from the downstream deck edge; the scour begins at about one deck width upstream the bridge while the deposition occurs at about 2.5 deck widths downstream the bridge; and the maximum scour depth decreases with increas-ing sediment size, but increases with deck inundation. The theoretical analysis shows that: bridge scour can be divided into three cases, i.e. downstream unsubmerged, partially submerged, and totally submerged. For downstream unsubmerged flows, the maximum bridge scour depth is an open-channel problem where the conventional methods in terms of critical velocity or bed shear stress can be applied; for partially and totally submerged flows, the equilibrium maximum scour depth can be described by a scour and an inundation similarity number, which has been confirmed by experiments with two decks and two sediment sizes. For application, a design and field evaluation procedure with examples is presented, including the maximum scour depth and scour profile.

  8. 大跨度梁拱组合桥的梁轨相互作用设计参数研究%Study of Design Parameters of Beam-Track Interaction of Long Span Hybrid Bridge of Beam and Arch

    Institute of Scientific and Technical Information of China (English)

    戴公连; 刘瑶

    2015-01-01

    为了解梁轨相互作用设计参数对大跨度梁拱组合桥无缝线路的影响,以兰渝线广元段某(82.9+172+82.9) m梁拱组合桥为例,采用ANSYS 软件建立了考虑拱肋—吊杆—主梁—桥墩—桩基—轨道梁轨系统一体化有限元模型,分析了拱肋与吊杆升温、纵向阻力模型、吊杆间距、桥墩高度、制动力率、风荷载等参数对钢轨纵向力的传递规律。结果表明:拱肋升温对钢轨应力的影响较大,计算钢轨伸缩力时,按梁体升温15℃考虑较为安全;梁拱组合桥的梁轨相互作用根据《铁路无缝线路设计规范》计算较为安全;钢轨制动力随固定墩高度的增加而增大,固定墩的墩顶水平力与其墩高基本呈线性递减关系;钢轨应力随吊杆间距的增大而增加;钢轨的最大制动拉、压应力和固定墩的墩顶水平力均与制动力率呈线性关系;风荷载作用下,钢轨应力可达5.8 M Pa以上,风速较大区域需考虑风荷载对钢轨的影响。%To understand the effect of the design parameters of beam‐track interaction on the continuously welded rail on long span hybrid bridge of beam and arch ,a hybrid bridge of beam and arch with span arrangement (82 .9 + 172 + 82 .9 ) m on the Guangyuan section of Lanzhou‐Chongqing Railway was taken as an example ,a finite element model considering the integration of the arch rib -hanger-main beam -pier-pile foundation -beam‐track system was established ,u‐sing the software ANSYS and the effect of the design parameters ,such as the temperature rise in the arch rib and hanger ,longitudinal resistance model ,hanger spacing ,pier height ,braking force ratio and wind load ,on the longitudinal force transmission laws of the steel rail were analyzed . T he results of the analysis show that the effect of the temperature rise in the arch rib on the steel rail stress is great and w hen the steel rail expansion force is calculated

  9. Evaluation of High-Speed Railway Bridges Based on a Nondestructive Monitoring System

    Directory of Open Access Journals (Sweden)

    Mosbeh R. Kaloop

    2016-01-01

    Full Text Available Recently, trains’ velocities in Korea increased more than the speed used in the design of some bridges. Accordingly, this paper demonstrates the evaluation of a railway bridge due to high-speed trains’ movement. A nondestructive monitoring system is used to assess the bridge performance under train speeds of 290, 360, 400 and 406 km/h. This system is comprised of a wireless short-term acceleration system and strain monitoring sensors attached to the bridge girder. The results of the analytical methods in time and frequency domains are presented. The following conclusions are obtained: the cross-correlation models for accelerations and strain measurements are effective to predict the performance of the bridge; the static behavior is increased with train speed developments; and the vibration, torsion, fatigue and frequency contents analyses of the bridge show that the bridge is safe under applied trains’ speeds.

  10. Estimation of Curvature Changes for Steel-Concrete Composite Bridge Using Fiber Bragg Grating Sensors

    Directory of Open Access Journals (Sweden)

    Donghoon Kang

    2013-01-01

    Full Text Available This study is focused on the verification of the key idea of a newly developed steel-concrete composite bridge. The key idea of the proposed bridge is to reduce the design moment by applying vertical prestressing force to steel girders, so that a moment distribution of a continuous span bridge is formed in a simple span bridge. For the verification of the key technology, curvature changes of the bridge should be monitored sequentially at every construction stage. A pair of multiplexed FBG sensor arrays is proposed in order to measure curvature changes in this study. They are embedded in a full-scale test bridge and measured local strains, which are finally converted to curvatures. From the result of curvature changes, it is successfully ensured that the key idea of the proposed bridge, expected theoretically, is viable.

  11. Online Bridge Crack Monitoring with Smart Film

    Directory of Open Access Journals (Sweden)

    Benniu Zhang

    2013-01-01

    Full Text Available Smart film crack monitoring method, which can be used for detecting initiation, length, width, shape, location, and propagation of cracks on real bridges, is proposed. Firstly, the fabrication of the smart film is developed. Then the feasibility of the method is analyzed and verified by the mechanical sensing character of the smart film under the two conditions of normal strain and crack initiation. Meanwhile, the coupling interference between parallel enameled wires of the smart film is discussed, and then low-frequency detecting signal and the custom communication protocol are used to decrease interference. On this basis, crack monitoring system with smart film is designed, where the collected crack data is sent to the remote monitoring center and the cracks are simulated and recurred. Finally, the monitoring system is applied to six bridges, and the effects are discussed.

  12. Construction and control technology of the main bridge superstructure of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Hong; Luo Chenbin; Zhang Yongtao; You Xinpeng

    2009-01-01

    The Sutong Yangtze River Bridge (short as Sutong Bridge) is now the largest span cable-stayed bridge in the world. The construction of the superstructure of the middle bridge covered several stages including erection of the big block girders for the side span, assistant span and tower area, erection of standard girders and closure of the middle span. The big block girders were hoisted by a floating crane, and the standard girders were hoisted by a double crane system on the deck. The pushing assistant method was adopted for the middle span closure construction. Furthermore, key technologies and innovative methods used in the processes of girder erection and cable assemblage in all stages were expatiated systematically. An all-stage self- adaptive geometry control method was used in the construction process. By accurately controlling the unstressed dimensions and shape of all structural components in each step, and realization that the control system and the controlled system adapt to each other, the goal was to make control of the final line shape and inner force of the bridge structure achievable. Two solutions, including GPS based and total station based dynamic geometry monitoring systems, were used to resolve the measure problem under the wide-range of wind-induced vibrations in the long cantilever state. Finally, research on the wind-induced vibration of the superstructure during the construction period was executed. Buffeting response analysis to the longest single and double cantilever states were carried out. The analysis and evaluation of wind resistance safety of the main girders under the longest single cantilever state was made, and corresponding wind resistance measures were suggested. The as-built geometric error and cable force error were controlled in a required design range, and this whole technological achievement can be a benchmark for construction of other large span cable-stayed bridges in the future.

  13. 240 W全桥移相ZVS变换器的设计%Design of a 240 W full-bridge converter with phase shift control and zero voltage switching

    Institute of Scientific and Technical Information of China (English)

    张本庚; 刘平

    2011-01-01

    The phase-shifted full-bridge zero-voltage-switching (PS-FB-ZVS) PWM converter is widely used in medium and high power levels. However, there are two problems existing in this kind of converter; one is that lagging leg has narrow zero-voltage-switching ranges,and the other is that the output rectifier diodes suffer the parasitic oscillation and voltage spike resulted by the reverse recovery of the rectifier diodes. The converter discussed in the literalure one had wide zero-voltage-switching ranges of lagging leg switches by using the magnetizing current. In addition, the resonance between the leakage inductor of the transformer and the rectifier capacitors could reduce the current stresses of the rectifier diodes and coeduction losses. Based on the principle of the converter, one 240 W zero-voltage-switching (ZVS) soft-switching power supply on the phase shift control was designed The procedures of main circuit design were presented. The experimental waveforms were given in the end.%移相全桥零电压变换器在中大功率场合中得到了广泛的应用,但其滞后臂只能在较窄的负载范围内实现软开关,并且其输出整流二极管反向恢复时产生严重的寄生振荡,二极管上存在很高的尖峰压.而文献[1]中变换器的滞后臂利用励磁电感电流可以在较宽的负载范围内实现软开关.变压器的漏感与电容的谐振可以减小整流管的电流应力和导通损失.基于此变换器的工作原理,设计了一台240 W移相控制零电压软开关电源,给出了主电路的设计过程,最后给出了实验波形.

  14. Cascaded resonant bridge converters

    Science.gov (United States)

    Stuart, Thomas A. (Inventor)

    1989-01-01

    A converter for converting a low voltage direct current power source to a higher voltage, high frequency alternating current output for use in an electrical system where it is desired to use low weight cables and other circuit elements. The converter has a first stage series resonant (Schwarz) converter which converts the direct current power source to an alternating current by means of switching elements that are operated by a variable frequency voltage regulator, a transformer to step up the voltage of the alternating current, and a rectifier bridge to convert the alternating current to a direct current first stage output. The converter further has a second stage series resonant (Schwarz) converter which is connected in series to the first stage converter to receive its direct current output and convert it to a second stage high frequency alternating current output by means of switching elements that are operated by a fixed frequency oscillator. The voltage of the second stage output is controlled at a relatively constant value by controlling the first stage output voltage, which is accomplished by controlling the frequency of the first stage variable frequency voltage controller in response to second stage voltage. Fault tolerance in the event of a load short circuit is provided by making the operation of the first stage variable frequency voltage controller responsive to first and second stage current limiting devices. The second stage output is connected to a rectifier bridge whose output is connected to the input of the second stage to provide good regulation of output voltage wave form at low system loads.

  15. Behavior of FRP Link Slabs in Jointless Bridge Decks

    Directory of Open Access Journals (Sweden)

    Aziz Saber

    2012-01-01

    Full Text Available The paper investigated the use of fiberglass-reinforced plastic (FRP grid for reinforcement in link slabs for jointless bridge decks. The design concept of link slab was examined based on the ductility of the fiberglass-reinforced plastic grid to accommodate bridge deck deformations. The implementation of hybrid simulation assisted in combining the experimental results and the theoretical work. The numerical analyses and the experimental work investigated the behavior of the link slab and confirmed its feasibility. The results indicated that the technique would allow simultaneous achievement of structural need, lower flexural stiffness of the link slab approaching the behavior of a hinge, and sustainability need of the link slab. The outcome of the study supports the contention that jointless concrete bridge decks may be designed and constructed with fiberglass-reinforced plastic grid link slabs. This concept would also provide a solution to a number of deterioration problems associated with bridge deck joints and can be used during new construction of bridge decks. The federal highway administration provided funds to Louisiana Department of Transportation through the innovative bridge research and development program to implement the use of FRP grid as link slab.

  16. Segmental Bridges under Combined Torsion, Bending and Shear

    Institute of Scientific and Technical Information of China (English)

    黄真; 刘西拉

    2003-01-01

    Segmental bridges with unbonded prestressed tendons have some advantages, such as the weather independence and the corrosion protection of prestressing tendons. This paper analyzed the behavior of a prestressed segmental bridge with unbonded tendons under combined loading of torsion, bending and shear. According to the experiment research, a modified skew bending model was developed to calculate the bearing capacity of segmental bridges subjected to combined bending, shear and torsion. The finite element method was used to investigate the deflection behaviors of such structure, also to check the theoretical model. The theoretical and FEM research resuits were compared favorably with the test results from Technical University of Braunschweig, Germany. Finally, suggestion for the design and construction of segmental bridges with external prestressing was made.

  17. Bridge SHM system based on fiber optical sensing technology

    Science.gov (United States)

    Li, Sheng; Fan, Dian; Fu, Jiang-hua; Huang, Xing; Jiang, De-sheng

    2015-09-01

    The latest progress of our lab in recent 10 years on the area of bridge structural health monitoring (SHM) based on optical fiber sensing technology is introduced. Firstly, in the part of sensing technology, optical fiber force test-ring, optical fiber vibration sensor, optical fiber smart cable, optical fiber prestressing loss monitoring method and optical fiber continuous curve mode inspection system are developed, which not only rich the sensor types, but also provides new monitoring means that are needed for the bridge health monitoring system. Secondly, in the optical fiber sensing network and computer system platform, the monitoring system architecture model is designed to effectively meet the integration scale and effect requirement of engineering application, especially the bridge expert system proposed integration of sensing information and informatization manual inspection to realize the mode of multi index intelligence and practical monitoring, diagnosis and evaluation. Finally, the Jingyue bridge monitoring system as the representative, the research on the technology of engineering applications are given.

  18. Noise Reduction of Fractional Source in Cryogenic Current Comparator Bridge

    Directory of Open Access Journals (Sweden)

    C. Jassadajin

    2013-10-01

    Full Text Available In this work, a resistance measurement is done at both high accuracy and precision using Cryogenic Current Comparator (CCC bridge system [1]. A CCC bridge circuit consists of three parts: coil, current source and detector parts. There are electronic components in the current source of the system. They generate thermal noise in the measurement system. This paper shows the noise reduction in a fractional source of CCC Bridge which is a ramp generator. The bridge receives the voltage signal, which is supplied to a CCC coil to achieve the magnetic flux balance condition inside the superconductorshield, from a null detector. By analysing the noise of the circuit in the fractional part and improving the circuit, it can minimize the noise to obtain a better output of the fractional source for improved accurate and more stability. Finally, the noise can be reduced for a designed bandwidth, a unity noise gain and minimized input resistance in the circuit.

  19. Discrete vortex method simulations of aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan;

    The meshless and remeshed Discrete Vortex Method (DVM) has been widely used in academia and by the industry to model two-dimensional flow around bluff bodies. The implementation “DVMFLOW” [1] is used by the bridge design company COWI to determine and visualise the flow field around bridge sections......, and to determine aerodynamic forces and the corresponding flutter limit. A simulation of the three-dimensional bridge responseto turbulent wind is carried out by quasi steady theory by modelling the bridge girder as a line like structure [2], applying the aerodynamic load coefficients found from the current version...... of DVMFLOW in a strip wise fashion. Neglecting the aerodynamic admittance, i.e. the correlation of the instantaneous lift force to the turbulent fluctuations in the vertical velocities, leads to higher response to high frequency atmospheric turbulence than would be obtained from wind tunnel tests....

  20. Discrete vortex method simulations of aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan;

    velocity spectra are found in good agreement with the target spectra. The aerodynamic admittance of the structure is measured by sampling vertical velocities immediately upstream of the structure and the lift forces on the structure. The method is validated against the analytic solution for the admittance......The meshless and remeshed Discrete Vortex Method (DVM) has been widely used in academia and by the industry to model two-dimensional flow around bluff bodies. The implementation “DVMFLOW” [1] is used by the bridge design company COWI to determine and visualise the flow field around bridge sections......, and to determine aerodynamic forces and the corresponding flutter limit. A simulation of the three-dimensional bridge responseto turbulent wind is carried out by quasi steady theory by modelling the bridge girder as a line like structure [2], applying the aerodynamic load coefficients found from the current version...

  1. Venture Creation Programs: Bridging Entrepreneurship Education and Technology Transfer

    Science.gov (United States)

    Lackéus, Martin; Williams Middleton, Karen

    2015-01-01

    Purpose: The purpose of this paper is to explore how university-based entrepreneurship programs, incorporating real-life venture creation into educational design and delivery, can bridge the gap between entrepreneurship education and technology transfer within the university environment. Design/methodology/approach: Based on a literature review…

  2. Bridging Cultures: Evaluating Teachers' Understanding of Cross-Cultural Conflicts.

    Science.gov (United States)

    Trumbull, Elise; Greenfield, Patricia; Quiroz, Blanca; Rothstein-Fisch, Carrie

    The Bridging Cultures Project is a collaboration among several researchers and teachers (n=8) to design professional development activities on the topic of cross-cultural understanding. During the fall of 1996, participating teachers will be given a pre-assessment and post-assessment. The assessments are designed to give some information on how…

  3. Acquisition and Analysis of Dynamic Responses of a Historic Pedestrian Bridge using Video Image Processing

    Science.gov (United States)

    O'Byrne, Michael; Ghosh, Bidisha; Schoefs, Franck; O'Donnell, Deirdre; Wright, Robert; Pakrashi, Vikram

    2015-07-01

    Video based tracking is capable of analysing bridge vibrations that are characterised by large amplitudes and low frequencies. This paper presents the use of video images and associated image processing techniques to obtain the dynamic response of a pedestrian suspension bridge in Cork, Ireland. This historic structure is one of the four suspension bridges in Ireland and is notable for its dynamic nature. A video camera is mounted on the river-bank and the dynamic responses of the bridge have been measured from the video images. The dynamic response is assessed without the need of a reflector on the bridge and in the presence of various forms of luminous complexities in the video image scenes. Vertical deformations of the bridge were measured in this regard. The video image tracking for the measurement of dynamic responses of the bridge were based on correlating patches in time-lagged scenes in video images and utilisinga zero mean normalisedcross correlation (ZNCC) metric. The bridge was excited by designed pedestrian movement and by individual cyclists traversing the bridge. The time series data of dynamic displacement responses of the bridge were analysedto obtain the frequency domain response. Frequencies obtained from video analysis were checked against accelerometer data from the bridge obtained while carrying out the same set of experiments used for video image based recognition.

  4. Architectural design in the east artificial island of the Hongkong-Zhuhai-Macao Bridge:the combination of natural and humanistic cultures%港珠澳大桥东人工岛岛上建筑设计--自然与人文的结合

    Institute of Scientific and Technical Information of China (English)

    冯颖慧; 姜立得

    2015-01-01

    通过研究分析港珠澳大桥人工岛的自然环境、人文环境及大桥建造的背景,对岛上集观光、商业、展览、交通服务等功能的大型公共建筑设计与岛上广场景观设计进行呼应与融合。最大程度地发挥珠江口海中央的独特地理特性及香港、珠海、澳门三地的人文特色,成为港珠澳大桥里程碑式工程中的精髓。%Through studying and analyzing the natural and cultural environment, and the bridge construction background of the Hongkong-Zhuhai- Macao Bridge, echo and fuse the square sightseeing designs of the island and the large public building designs, such as sightseeing, business, exhibitions, transport services and etc. Maximize the unique geographical center of the Pearl River Estuary characteristics and the cultural characteristics of Hongkong, Zhuhai and Macao. It would be the essence of the landmark Hongkong-Zhuhai-Macao Bridge project.

  5. Real-time seismic monitoring of the integrated cape girardeau bridge array and recorded earthquake response

    Science.gov (United States)

    Celebi, M.

    2006-01-01

    This paper introduces the state of the art, real-time and broad-band seismic monitoring network implemented for the 1206 m [3956 ft] long, cable-stayed Bill Emerson Memorial Bridge in Cape Girardeau (MO), a new Mississippi River crossing, approximately 80 km from the epicentral region of the 1811-1812 New Madrid earthquakes. The bridge was designed for a strong earthquake (magnitude 7.5 or greater) during the design life of the bridge. The monitoring network comprises a total of 84 channels of accelerometers deployed on the superstructure, pier foundations and at surface and downhole free-field arrays of the bridge. The paper also presents the high quality response data obtained from the network. Such data is aimed to be used by the owner, researchers and engineers to assess the performance of the bridge, to check design parameters, including the comparison of dynamic characteristics with actual response, and to better design future similar bridges. Preliminary analyses of ambient and low amplitude small earthquake data reveal specific response characteristics of the bridge and the free-field. There is evidence of coherent tower, cable, deck interaction that sometimes results in amplified ambient motions. Motions at the lowest tri-axial downhole accelerometers on both MO and IL sides are practically free from any feedback from the bridge. Motions at the mid-level and surface downhole accelerometers are influenced significantly by feedback due to amplified ambient motions of the bridge. Copyright ASCE 2006.

  6. Experimental study on the width of the turbulent area around bridge pier

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Yuan; LIU Zu-yuan

    2007-01-01

    At present, the method of calculating the turbulent flow width around the bridge pier is not given in the "Standard for Inland River Navigation" (GB50139-2004) in China, and the bridge designer usually increases the bridge span in order to ensure the navigation safety, which increases both of the structural design difficulty and the project investments. Therefore, it is extremely essential to give a research on the turbulent flow width around the bridge pier. Through the experiments of the fixed bed and the mobile bed, the factors influencing the turbulent flow width around the bridge pier have been analyzed, such as the approaching flow speed, the water depth, the angles between the bridge pier and the flow direction, the sizes of bridge pier, the shapes of the bridge pier, and the scouring around the bridge pier, etc. Through applying the dimension analytic method to the measured data, the formula of calculating the turbulent flow width around the bridge pier is then inferred.

  7. Overlapping reliable control for a cable-stayed bridge benchmark

    OpenAIRE

    Bakule, Lubomir; Paulet-Crainiceanu, Fideliu; Rodellar Benedé, José; Rossell Garriga, Josep Maria

    2005-01-01

    The brief presents a reliable 1-out-2 reduced order control design strategy for a cable-stayed bridge benchmark using two overlapping subsystems and the linear quadratic Gaussian (LQG) design. Reliability with regard to controller failures is considered. Local controllers are designed for reduced order subsystems of expanded system. They are implemented and evaluated on the original overall system model. Two different sets of numerical experiments of reliable control design within 1-out-2 con...

  8. Towards Sustainable Construction: Life Cycle Assessment of Railway Bridges

    DEFF Research Database (Denmark)

    Du, Guangli

    implementation is under great expectations to set a new design criterion, to optimize the structural design towards the environmental sustainability, and to assist the decision-making among design proposals. This thesis consists of two parts: an extended summary and three appended papers. Part one gives......Since last few decades, the increased pressure from the environmental issues of natural resource depletion, global warming and air pollution have posed a great challenge worldwide. Among all the industrial fields, bridge infrastructures and their belonged construction sector contribute to a wide...... a more detailed theoretical review of the current literatures and knowledge associated with bridge LCA, by highlighting the great challenging issues. A systematic flowchart is presented both in Paper I and Paper II for how to model and assess the bridge life cycle, together by coping with the structural...

  9. Liquid-Bridge Breaking Limits

    Science.gov (United States)

    Macner, Ashley; Steen, Paul

    2011-11-01

    Wet adhesion by liquid bridges in large arrays shows promise for use in lightweight, controllable on-demand devices. Applications include grab/release of wafer substrates, transport of micron-sized tiles for use in 3D printing and micro-dosing of personalized pharmaceutical drugs. By wetting and spreading, a drop can form a bridge and thereby ``grab'' a nearby solid substrate. By volume decrease or extension, the bridge can break. The breaking limit corresponds to bridge instability which can be predicted, knowing the static mechanical response of the bridge. Mechanical behaviors include force-volume (FV), pressure-volume (pV) and force-length (FL) responses. Instability crucially depends on the mode of failure - failure under constant-force or constant length are typical cases. We study single bridge equilibria for their breaking limits. FV diagrams for the pin-pin equal and pin-pin unequal radii boundary conditions for different bridge heights are measured in the laboratory. The FL response in the case of pin-pin equal radii is also measured. Results are compared to predictions of static theory. Static results are then used to compare to dynamical sequences where volume is driven quasistatically by syringe or an electro-osmotic pump. As the breaking limit is approached, the shape deformation accelerates leading to non-equilibrium shapes not captured by the static analysis.

  10. Bridge Creek IMW database - Bridge Creek Restoration and Monitoring Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The incised and degraded habitat of Bridge Creek is thought to be limiting a population of ESA-listed steelhead (Oncorhynchus mykiss). A logical restoration...

  11. National Bridge Inventory - National Geospatial Data Asset (NGDA) Bridges

    Data.gov (United States)

    Department of Transportation — The NBI (NTAD 2015) is a collection of information (database) describing the more than 610,000 of the Nation's bridges located on public roads, including Interstate...

  12. Sustainable Bridge Procurement Considering Life-Cycle Cost, Life-Cycle Assessment and Aesthetics

    DEFF Research Database (Denmark)

    Safi, Mohammed; Du, Guangli; Simonsson, Peter

    2016-01-01

    The lack of a flexible but systematic approach for integrating lifecycle aspects into bridge investment decisions is a major obstacle hindering the procurement of sustainable bridge infrastructures. This paper addresses this obstacle by introducing a holistic approach that agencies could use...... to procure the most “sustainable” (lifecycle-efficient) bridge through a fair design-build (D-B) tendering process, considering all the main aspects: life-cycle cost (LCC), service life-span, aesthetic demands and environmental impacts (LCA)....

  13. Dynamic analysis of a portal frame railway bridge using frequency dependent soil structure interaction

    OpenAIRE

    Arvidsson, Therese; Li, Jiajia

    2011-01-01

    With the development of high-speed railroads the dynamic behaviour of railroad bridges is increasingly important to explore. Deeper knowledge about the influence of different factors and what should be included in a model is essential if the designer shall be able to make reliable estimates of responses in existing and new structures. One factor is the soil-structure interaction (SSI), describing how the foundation of the bridge and the soil properties affect the behavior of the bridge under ...

  14. Rational design of azide-bridged bimetallic complexes. Crystal structure and magnetic properties of Fe(III)MFe(III) (M = Ni(II) and Cu(II)) trinuclear species.

    Science.gov (United States)

    Colacio, Enrique; Costes, Jean-Pierre; Domínguez-Vera, José M; Maimoun, Ikram Ben; Suárez-Varela, José

    2005-01-28

    The first examples of azide-bridged bimetallic trinuclear complexes ([M(cyclam)][FeL(N3)(mu1,5-N3)]2) (H2L = 4,5-dichloro-1,2-bis(pyridine-2-carboxamido) benzene) have been structurally and magnetically characterized.

  15. The Vertical Rotating Structure Design of Cable-stayed Bridge Pylon Based on the Finite Element%基于有限元的斜拉桥索塔竖转结构件设计

    Institute of Scientific and Technical Information of China (English)

    张宝宏

    2014-01-01

    Using vertical method forward the steel tower type cable-stayed bridge body mounted, to save time, reduce the co-st.%利用竖转法进行钢塔式斜拉桥塔身安装,以达到节省工期、降低成本的目的。

  16. Complex Testing of the Bridges

    Directory of Open Access Journals (Sweden)

    Savić Adrijana

    2016-01-01

    Full Text Available This article describes the process of examining bridges. AB road bridge, founded on the columns by the Karpoš system and damaged due to erosive action of the river, is given as an example. The first tests of the bridge are conducted on the impact load of V 300, because of the appearance of longitudinal cracks. The results of the columns testing are presented in this paper, as well as the rehabilitation measures thus increasing the load capacity of the column.

  17. Reliability Assessment of Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Middleton, C. R.

    This paper is partly based on research performed for the Highways Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: concrete bridges". It contains the details of a methodology which can be used to generate Whole Life (WL) reliability...... profiles. These WL reliability profiles may be used to establish revised rules for concrete bridges. This paper is to some extend based on Thoft-Christensen et. al. [1996], Thoft-Christensen [1996] et. al. and Thoft-Christensen [1996]....

  18. Excellent Combination of Concept,Design and Technology——Analysis of the Garden of 10,000 Bridges in the 2011 Xi'an International Horticulture Exhibition%理念·设计·技术的优秀结合——2011西安世园会万桥园解读

    Institute of Scientific and Technical Information of China (English)

    马冀汀; 岳邦瑞

    2011-01-01

    This article analyses the Garden of 10,000 bridges in the 2011 Xi'an International Horticulture Exhibition. The garden designed by Adriaan Geuze who is the chief designer of WEST 8.First,the article focuses on the design ideas,pointing out the theme of the garden:"Experience the life course",as well as the "to suit both refined and popular tasxtes" concept.Then the article looks into the design techniques and technology,believes that Garden of 10,000 bridges is an excellent combination of concept,design and technology.%以WEST 8主创设计师高伊策在2011西安世园会的"万桥园"为解读对象,首先分析了的该作品的构思源泉和设计理念,指出作品所传达的"体验生命历程"的主题,以及所反映的"雅俗共赏"观念;继而对作品设计手法与技术进行了分析,认为万桥园是理念、设计与技术的优秀结合,作品所呈现的整体性、亲和力是其成功的关键所在。

  19. Design Analysis on Steel-Concrete Transition Section of Main Girder of Shangdi Bridge on Beijing-Xinjiang Expressway%京新上地桥主梁钢-混过渡段的设计分析

    Institute of Scientific and Technical Information of China (English)

    徐升桥; 刘永锋

    2013-01-01

    京新上地桥的曲线混凝土主梁采用单点顸推法施工,顶推总重250 000 kN,顶推距离213 m,顶推过程最大悬臂长度63 m.钢导梁预埋于主梁前端,通过剪力连接件和混凝土箱梁连接成整体,以传递顶推过程中的弯矩和剪力.对钢-混凝土过渡段顶、底、腹板的连接件受力性能进行设计分析,并建立实体模型详细分析最不利工况下关键部位的局部应力,结果表明界面连接可靠,钢-混凝土过渡段变形协调、应力分布均匀,设计合理.%Single-point incremental launching method is employed to construct the curved concrete main girder of Shangdi Bridge on Beijing - Xinjiang Expressway. During the incremental launching construction, the total launching weight, distance and maximum cantilever length is respectively 25 000 t, 213 m and 63 m. In order to transfer bending moment and shear force, the steel launching nose is pre-embedded in the front end of the concrete main girder, and is integrally connected with the concrete box girder by shear connectors. For the steel-concrete transition section; mechanical performance of connectors at the top, bottom and web slabs are analyzed firstly; and then, local stress at key positions under the most unfavorable conditions are precisely analyzed by means of solid model. The analysis results show that: connection of the interface is reliable, deformation of the steel-concrete transition section is compatible, and stress distribution is uniform, which indicate that the design is reasonable.

  20. 大跨桥梁健康监测系统设计构成及其进展%Designed Components and Development of Health Monitoring Systems for Long Span Bridges

    Institute of Scientific and Technical Information of China (English)

    王戒躁; 钟继卫; 王波

    2009-01-01

    With the constant construction of the new types of long span, lightweight and flexible structure bridges, the safety and durability of the bridges in operation state have attracted great concern from engineering circle and the real-time structural health monitoring and the near real-time structural safety evaluation of the bridges have also become the hot research subjects in the engineering and academic circles. The contents and components of the monitoring and evaluation systems are presented herewith, the current research of the monitoring and evaluation systems for some major bridges at home and abroad are reviewed, the state-of-the-art, development tendency and prospecting of the monitoring system and evaluation items are described and the research findings of the monitoring system for Wuhan Yangluo Changjiang River Bridge are particularly analyzed.%随着大跨、轻、柔等新型桥型的不断建造,桥梁结构运营状态的安全性及耐久性受到工程界高度重视.大跨度桥梁的实时结构健康监测和近实时结构安全评估工作也成为工程界及学术界研究的热点问题.介绍桥梁健康监测与评估系统的内容及系统构成,简要回顾国内外大型桥梁健康监测与评估系统的研究现状,阐述桥梁健康监测与评估项目的发展现状、趋势及前景,并重点分析武汉阳逻长江大桥健康监测系统的研究成果.

  1. The Higgs Bridge

    CERN Document Server

    Allen, Roland E

    2013-01-01

    The particle recently discovered at the Large Hadron Collider near Geneva is almost certainly a Higgs boson, the long-sought completion of the Standard Model of particle physics. But this discovery, an achievement by more than six thousand scientists (including students), is actually much more than a mere capstone of the Standard Model. It instead represents a bridge from the Standard Model to exciting discoveries of the future, at higher energies or in other experiments, and to the properties of matter at very low temperatures. The mere existence of a particle with zero spin implies a need for new physics, with the most likely candidate being supersymmetry, which requires that every known particle has a superpartner yet to be discovered. And phenomena similar to the Higgs are seen in superconducting metals and superfluid gases at low temperatures, which extend down to a millionth or even a billionth of a degree Kelvin. So the discovery of a Higgs boson has a central place in our attempts both to achieve a tr...

  2. Seismic Analysis for Rigid-Framed Prestressed Reinforced Concrete Bridge in Tianjin Light Railway

    Institute of Scientific and Technical Information of China (English)

    丁阳; 李楠; 李忠献

    2004-01-01

    The seismic analysis of a rigid-framed prestressed concrete bridge in Tianjin Light Railway is performed. A 3-D dynamic finite element model of the bridge is established considering the weakening effect caused by the soft soil foundation. After the dynamic characteristics are calculated in terms of natural frequencies and modes, the seismic analysis is carried out using the modal response spectrum method and the time-history method, respectively. Based on the calculated results, the reasonable design values are finally suggested as the basis of the seismic design of the bridge, and meanwhile the problems encountered were also analyzed. Finally, some conclusions are drawn as: 1) Despite the superiority of rigid-framed prestressed concrete bridge, the upper and lower ends of the piers of the bridge are proved to be the crucial parts of the bridge, which are easily destroyed under designed earthquake excitations and should be carefully analyzed and designed; 2) The soft soil foundation can possibly result in rather weakening of the lateral rigidity of the rigid-framed bridge, and should be paid considerable attention; 3) The modal response spectrum method, combined with time-history method, is suggested for the seismic analysis in engineering design of the rigid-framed prestressed concrete bridge.

  3. Mineral bridges in nacre revisited

    CERN Document Server

    Checa, Antonio G; Willinger, Marc-Georg

    2012-01-01

    We confirm with high-resolution techniques the existence of mineral bridges between superposed nacre tablets. In the towered nacre of both gastropods and the cephalopod Nautilus there are large bridges aligned along the tower axes, corresponding to gaps (150-200 nm) in the interlamellar membranes. Gaps are produced by the interaction of the nascent tablets with a surface membrane that covers the nacre compartment. In the terraced nacre of bivalves bridges associated with elongated gaps in the interlamellar membrane (> 100 nm) have mainly been found at or close to the edges of superposed parental tablets. To explain this placement, we hypothesize that the interlamellar membrane breaks due to differences in osmotic pressure across it when the interlamellar space below becomes reduced at an advanced stage of calcification. In no cases are the minor connections between superimposed tablets (< 60 nm), earlier reported to be mineral bridges, found to be such.

  4. Simulation of multivariate diffusion bridges

    DEFF Research Database (Denmark)

    Bladt, Mogens; Finch, Samuel; Sørensen, Michael

    We propose simple methods for multivariate diffusion bridge simulation, which plays a fundamental role in simulation-based likelihood and Bayesian inference for stochastic differential equations. By a novel application of classical coupling methods, the new approach generalizes a previously...

  5. Bridge Culture of Langde Village

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Langde, a village in Leishan County ofsouthwestern Guizhou province, is known for itslarge number of unique bridges bearing the distinctdesign style of the Miao ethnic group. Animpressive variety of well-preserved ancient

  6. TMD-Based Structural Control of High Performance Steel Bridges

    International Nuclear Information System (INIS)

    The purpose of this study is to investigate the effectiveness of structural control using tuned mass damper (TMD) for suppressing excessive traffic induced vibration of high performance steel bridge. The study considered 1-span steel plate girder bridge and bridge-vehicle interaction using HS-24 truck model. A numerical model of steel plate girder, traffic load, and TMD is constructed and time history analysis is performed using commercial structural analysis program ABAQUS 6.10. Results from analyses show that high performance steel bridge has dynamic serviceability problem, compared to relatively low performance steel bridge. Therefore, the structural control using TMD is implemented in order to alleviate dynamic serviceability problems. TMD is applied to the bridge with high performance steel and then vertical vibration due to dynamic behavior is assessed again. In consequent, by using TMD, it is confirmed that the residual amplitude is appreciably reduced by 85% in steady-state vibration. Moreover, vibration serviceability assessment using 'Reiher-Meister Curve' is also remarkably improved. As a result, this paper provides the guideline for economical design of I-girder using high performance steel and evaluates the effectiveness of structural control using TMD, simultaneously.

  7. Procurement of Beams in Multiple D&B Bridge Projects

    Directory of Open Access Journals (Sweden)

    CT. Ramanathan

    2010-06-01

    Full Text Available Selected infrastructure development projects are being implemented by Design and Build (D&B pocurement system in Sabah (East Malaysia by the Public Works Department (PWD. In the first phase 45 bridge replacement projects were awarded in 5 packages. These simultaneous multiple Bridge projects are for the development of the backward areas and hence their timely completion is utmost important. Procurement and production of bridge beams have been the critical element of construction in these rural areas and no researches has been reported on various aspects of procurement of the bridge beams in multiple D&B projects. The aspects of procurement researched in this work include the determination of a common beam element for the ease of procurement and the optimization of the construction methodology, the finalization and purchasing plate dimensions to suite the manufacturer's production range, the delivery of materials, the planning and monitoring of fabrication, the preparation and assembly, and the erection and launching of beams. The beams are optimized using element optimization techniques. The most important problems in fabricating steel girders were in planning and scheduling of materials for the fabrication and the fabrication process. Findings in all the aspects of production of steel girders are highlighted through a case study of six long span bridges at various locations in Sabah. Solutions drawn from lessons learnt which minimize wastages, and aids in timely completion of beams in multiple bridge construction are discussed.

  8. An integrated FBG sensing system for bridge health monitoring

    Science.gov (United States)

    Sun, Ru-Jiao; Sun, Zhi; Dan, Dan-Hui; Sun, Li-Min

    2006-03-01

    Thanking to its distinguishing advantages including wavelength multiplexing capability, miniature size, high sensitivity, immunity from electro-magnetic interference and etc, the fiber Bragg grating (FBG) sensing technologies are regarded as a competent candidate for the bridge long-term health monitoring. According to the shifted Bragg wavelength of the light reflected by a fiber grating, the FBG sensors can accurately measure various physical properties such as strain, temperature, displacement, acceleration and corrosion. One special advantage of the FBG sensing technology is that only one demodulation device is required to acquire various physical properties simultaneously. Compared with the bridge health monitoring system using conventional sensors, this advantage makes the quasi-distributed sensing possible and data transmission more convenient because many FBG sensors can be connected in series by a single fiber. In this paper, an integrated FBG sensing system is presented for monitoring the physical state of a real bridge, the main-navigation channel cable-stayed bridge of the Donghai Bridge. The strain variation of two selected sections in the construction stage and during the load trial test are continuously monitored. The results of this study will supply a good guidance for the use of FBG sensors on the health monitoring of real bridges. Finally, the paper present the design and fabrication of an accelerometer based on the FBG technology for structure vibration monitoring.

  9. ANGIOGRAPHIC ASPECTS OF MYOCARDIAL BRIDGES

    Directory of Open Access Journals (Sweden)

    Sujatha. M

    2015-12-01

    Full Text Available Introduction: The segment of epicardial coronary artery that traverses intramurally through the myocardium and bridged by a bunch of cardiac muscle fibers is called tunneled artery or intramural artery. The band of cardiac muscle fibers passing over the tunneled artery segment is named as myocardial bridge. During angiography milking effect is observed during systole due to the external pressure of muscle fibers on the tunneled artery that leads to narrowing of vessel lumen and further ischemia. Materials & Methods: It is a prospective study performed from 2012- 2015 in cardiac centers available around Tirupati, Andhra Pradesh, South India. A total number of 2015 adult patients who underwent diagnostic coronary angiography were evaluated to detect myocardial bridges. With the informed consent the relevant data was collected from the patients and analyzed. Results: The prevalence of myocardial bridges was 3.17%. Among the 2015 patients 70.7% are males and 29.2% are females. Among 64 myocardial bridge positive cases 62.5% were male and 37.5% were female patients. Regarding coronary dominance 84% were right dominant and 14.4% were left dominant and 1.6% are balanced. The percentage incidence of myocardial bridging according to dominance was 3.01% for right dominant patients, 4.12% for left dominant patients and 3.1% for balanced dominant patients. In all the myocardial bridge positive cases they were located on the left anterior descending artery (LAD. According to diagnosis the patients with normal coronaries were 22.6%, patients with MILD CAD were 17.9%, patients with single vessel disease were 23.4%, patients with two vessel disease were 14.7% and the patients with triple vessel disease were 21.3%. The 64 myocardial bridging cases were grouped in to three groups according to their age. Incidence of double bridges was observed in 3 cases of which 66.7% males & 33.3% in females. Conclusion: These results show that Andhra Pradesh population are

  10. The stories of two bridges in Ghana

    DEFF Research Database (Denmark)

    Andreasen, Jørgen

    2004-01-01

    Public participation in bridge building was promoted by un habitat in the village of Mankrong. The neighbouring village did not participate in the construction of their bridge. The first flooding washed the second bridge down while the "participative bridge" stood up....

  11. An Expert System for Concrete Bridge Management

    DEFF Research Database (Denmark)

    Brito, J. de; Branco, F. A.; Thoft-Christensen, Palle;

    1997-01-01

    The importance of bridge repair versus new bridge construction has risen in recent decades due to high deterioration rates that have been observed in these structures. Budgets both for building new bridges and keeping the existing ones are always limited. To help rational decision-making, bridge...

  12. Stability of liquid crystalline bridges

    Science.gov (United States)

    Mahajan, Milind P.; Tsige, Mesfin; Taylor, P. L.; Rosenblatt, Charles

    1999-02-01

    The stability of cylindrical bridges of the liquid crystal octylcyanobiphenyl in an immiscible liquid bath was investigated in the nematic and smectic A phases. In the nematic phase the bridge was found to destabilize at a length-to-diameter (slenderness) ratio R similar to that of ordinary Newtonian fluids. On the other hand, the Bingham behavior of the smectic A phase, i.e., an apparent yield stress, enabled the formation of stable columns with R well in excess of π.

  13. Bridge connection of quantum Hall elementary devices

    CERN Document Server

    Callegaro, Luca

    2013-01-01

    Multiple-series and multiple-parallel connections of quantum Hall elementary devices allow the realization of multiple or fractional values of the quantized Hall resistance, rejecting the effect of contact and wiring resistances. We introduce here the multiple-bridge connection, which maintains the properties of multiple-series and parallel connections and allows more freedom in the choice of the topology of networks composed of quantum Hall elements, and the design of more efficient quantum Hall array resistance standards (and other devices). As an example, a 5-element network is analyzed in detail.

  14. Comparison of Temperature Loadings of Bridge Girders

    Directory of Open Access Journals (Sweden)

    J. Římal

    2008-01-01

    Full Text Available This paper compares the effect of temperature changes on the superstructure of bridges, above all the effect of non-uniform temperature. Loadings according to standards ESN 73 6203, ENV 1991-1-5 and DIN 1072 are compared here. The paper shows a short summary of temperature loading according to each standard and shows the comparison of bending moments arisen from these temperature loadings on superstructure made from continuous girder from a steel-concrete box girder with a composite concrete slab. With respect to a variety of design processes, the comparison is made without any coefficient of loading, combination or material. 

  15. Comparison of several innovative bridge cable surface modifications

    DEFF Research Database (Denmark)

    Kleissl, Kenneth; Georgakis, Christos T.

    into the effectiveness of helical fillets and pattern-indented surfaces has shown that, be-sides their purported ability to suppress rain-wind induced vibrations, they also modestly reduce drag forces at design wind velocities. This is of particular interest to bridge designers, as wind on stay planes of long......Over the last two decades, several bridge cable manufacturers have introduced surface modifications on the high-density polyethylene (HDPE) sheathing that is installed for the protection of inner cable strands or wires. The modifications are based on research undertaken predominantly in Europe...... and Japan, with two different prevailing systems: HDPE tubing fitted with helical fillets and tubing with pattern-indented surfaces. In the US and Europe, helical fillets dominate, whilst pattern indented sur-faces are more common in Asia, particularly for long-span cable-stayed bridges. Research...

  16. Studies on Technical Development of Railway Steel-Concrete Composite Cirider Bridges in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Steel-concrete composite girder bridge boasts the advantages of strong rigidity,low noise and low construction height.Along with the large-scale construction of passengerdedicated lines (PDL) and high-speed lines (HSL),tests and researches on steel-concrete composite girder bridges have been conducted with the main types of which including steel plate girder-concrete composite girder bridge,deck steel truss girder-concrete composite girder bridge,through steel truss girder-concrete composite girder bridge and through type tied arch composite girder bridge.Based on the application and researches on steel-concrete composite technology and in combination with the engineering construction of railway bridges,the construction of HSL and PDL and upgrading of existing lines for speed-up in China,this paper analyzes the main structural forms of through steel truss girder-concrete composite girder bridges with different spans and structure systems,carries out studies on the force acted upon these bridges and the related theory and methods for design and computation,and puts forward the solutions required in relation to the key technologies for further development of railway steel-concrete composite girder bridges.

  17. Economical bridge solutions based on innovative composite dowels and integrated abutments ecobridge

    CERN Document Server

    Băncilă, Radu

    2015-01-01

    This book is an outcome of the research project “ECOBRIDGE – Demonstration of ECOnomical BRIDGE solutions based on innovative composite dowels and integrated abutments – RFCS – CT 2010-00024”, which has been co-funded by the Research Fund for Coal and Steel (R.F.C.S.) of the European Community. The main topics of the book are the following: design of integral bridges, innovative composite dowels for the shear transmission, construction of bridges, structural analysis of bridges and monitoring. The book joins the technical experience and the contributions of the involved research partners. The technical content of all the papers is present-day in the field of the design, construction and monitoring of innovative composite bridges. The efficient design and construction improve and consolidate the market position of steel construction and steel producing industry. In addition, the advanced forms of construction are contributing to savings in material and energy consumption for the structure during prod...

  18. Contribution of Disulfide Bridges to the Thermostability of a Type A Feruloyl Esterase from Aspergillus usamii

    OpenAIRE

    Xin Yin; Die Hu; Jian-Fang Li; Yao He; Tian-Di Zhu; Min-Chen Wu

    2015-01-01

    The contribution of disulfide bridges to the thermostability of a type A feruloyl esterase (AuFaeA) from Aspergillus usamii E001 was studied by introducing an extra disulfide bridge or eliminating a native one from the enzyme. MODIP and DbD, two computational tools that can predict the possible disulfide bridges in proteins for thermostability improvement, and molecular dynamics (MD) simulations were used to design the extra disulfide bridge. One residue pair A126-N152 was chosen, and the res...

  19. Economic Functions Proposal of Urgency Prioritization of Investment Projects of Operated Railway Bridges

    Science.gov (United States)

    Pitoňák, Martin

    2014-12-01

    The main objective of the article is to describe the proposals of economic functions within the prioritization of urgency investments of operated railway bridges within a comprehensive evaluation of existing bridges. The purpose of the paper is a comprehensive assessment of existing bridges and to define determinants and determinants of decision-making and designing a mechanism of decision-making procedures of prioritized infrastructure measures in the form of repairs and reconstructions of bridges resulting from the records of supervising activities based not only on technical but also economic aspects to the railway infrastructure manager.

  20. A Cost Estimation Model for Repair Bridges Based on Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Mohamed Bouabaz

    2008-01-01

    Full Text Available Estimating the total cost of bridges repair and maintenance with high accuracy is an important components, and points to a need for a cost estimation model. This paper focuses on the development of a more accurate estimation model for repair and maintenance of bridges in developing countries using artificial neural networks. Cost and design data for two categories of repair bridges were used for training and testing our neural network model, with only three main parameters used in estimating the total cost of repairing bridges. An accuracy of 96% was achieved.

  1. Wind loads analysis at the anchorages of the Talavera de la Reina cable stayed bridge

    Directory of Open Access Journals (Sweden)

    L. Rosa

    2014-06-01

    Full Text Available This paper describes wind tunnel tests performed on wind tunnel models of the Talavera de la Reina cable stayed bridge. The work describes the aeroelastic model construction and it is focused on the evaluation and analysis of the mean and peak wind loads at the tower foundation and the cable anchorages since these data can be very useful by the bridge manufacturer as a support for the bridge design. The work is part of a complete wind tunnel study carried out to analyze the aeroelastic stability of the bridge.

  2. 基于NCP1396控制的LLC半桥串联谐振变换器的设计%Design of LLC Half-Bridge Series Resonance Converter Based on NCP1396

    Institute of Scientific and Technical Information of China (English)

    邓永清

    2016-01-01

    The fundamentals and internal structures of resonance controller NCP1396 were introduced firstly in this paper. Then, the working principle and mathematical model of LLC half-bridge series resonance converter were analyzed. In addition, typical applications of NCP1396 in LLC half-bridge series resonance converter were elaborated. Finally, related experimental waves were presented.%通过介绍谐振控制器NCP1396的基本原理及内部组成,对LLC半桥串联谐振变换器的工作原理及数学模型进行分析,详细论述了NCP1396在LLC半桥串联谐振变换器中的典型应用,并给出了相关实验波形。

  3. Seismic performance evaluation for super-long span cable-stayed bridges

    Institute of Scientific and Technical Information of China (English)

    Ye Aijun; Wu Shouchang

    2009-01-01

    Based on the capacity/demand (C/D) analysis of bridge components, and life cycle and performance based seismic design principles, a practical approach is developed for the seismic performance evaluation of super-long span cable-stayed bridges. According to the approach, the seismic performance evaluation of the Sutong Bridge, which is a cable-stayed bridge with a main span of 1 088 m, is completed, and the practicality of the approach is validated. The earthquake resistance level for super-long span cable-stayed bridges is discussed, including the earthquake level, its corresponding structural performance and check indices. And a set of formula for capacity/demand ratio calculation of bridge components is proposed.

  4. Nondestructive Evaluation of Railway Bridge by System Identification Using Field Vibration Measurement

    International Nuclear Information System (INIS)

    This paper presents a nondestructive evaluation approach for system identification (SID) of real railway bridges using field vibration test results. First, a multi-phase SID scheme designed on the basis of eigenvalue sensitivity concept is presented. Next, the proposed multi-phase approach is evaluated from field vibration tests on a real railway bridge (Wondongcheon bridge) located in Yangsan, Korea. On the steel girder bridge, a few natural frequencies and mode shapes are experimentally measured under the ambient vibration condition. The corresponding modal parameters are numerically calculated from a three-dimensional finite element (FE) model established for the target bridge. Eigenvalue sensitivities are analyzed for potential model-updating parameters of the FE model. Then, structural subsystems are identified phase-by-phase using the proposed model-updating procedure. Based on model-updating results, a baseline model and a nondestructive evaluation of test bridge are identified

  5. GPS Dynamic Monitoring Experiment and Result Analysis of Long-Span Cable-Stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    For the sake of timely appraising the working condition of the bridge, measuring the dynamic characteristics of the bridge structure is very important and necessary. A GPS dynamic monitoring test was carried out in the Wuhan Baishazhou Bridge, which is one of the longest span cable-stayed bridges having been built in China. This paper introduces the experimental implementing scheme and data processing method. The vibration characteristics of the middle span of cable-stayed bridge are availably obtained by use of the spectral analytic approach. The measuring results are very identical to the theoretical designed values. The research demonstrates that, with GPS receiver of the high sampling rate and suitable data processing method, the vibration characteristics of the bridge structure can be determined with high accuracy.

  6. Aerostatic Stability of Long-Span Cable-Stayed Bridges: Parametric Study

    Institute of Scientific and Technical Information of China (English)

    程进; 江见鲸; 肖汝诚; 项海帆

    2003-01-01

    The increasing span of cable-stayed bridges has focused more attention on the aerostatic stability of the design and construction of such bridges. This paper presents a new method to analyze the nonlinear aerostatic stability of cable-stayed bridges including all three components of the wind load and the geometric nonlinearity. The analysis was used to investigate the effects of the wind angle of incidence, the wind load of individual bridge elements, the sagging of cable elements, the changes of tower height and the changes of side span length on the aerostatic stability of cable-stayed bridges. The results show that the wind angle of incidence and the wind loads on the cables have an important effect on the aerostatic stability of cable-stayed bridges.

  7. Design Argumentation in Academic Design Education

    DEFF Research Database (Denmark)

    Dalsgaard, Peter; Dindler, Christian; Fritsch, Jonas

    2013-01-01

    We explore design argumentation as a resource when teaching interaction design in a university setting. We propose that design argumentation can help bridge between practice-based design education and theoretical issues from university curricula. In this paper, we outline the idea of design...

  8. A new multiconstraint method for determining the optimal cable stresses in cable-stayed bridges.

    Science.gov (United States)

    Asgari, B; Osman, S A; Adnan, A

    2014-01-01

    Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM). The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  9. Micro-bridge structure design of UFPA detector with high sensitive pixels%非制冷红外焦平面高灵敏像元微桥设计

    Institute of Scientific and Technical Information of China (English)

    范茂彦; 姜胜林; 谢甜甜; 张清峰; 张丽芳

    2009-01-01

    介绍了硅微桥结构的传热物理模型及其理论计算方法.提出一种厚膜像元尺寸为360μm×360μm,具有"桌形"绝热框架支撑的微桥结构像元,用有限元分析证明其有较小的热导G,能获得很高的响应率.微桥结构在非制冷红外焦平面(UFPA)单元探测器中起着力学支撑、热隔离和电连接的作用,其品质优劣直接影响着UFPA器件的成像性能.%The physical mode and theory of the heat transfer in micro-bridge structure are introduced. A kind of micro-bridge pixel is provided with thick-film pixel size of 360 μm×360μm and" desk-type" adiabatic frame support, and the analysis results by FEM show that the thermal conductivity G is small and high response rate can be obtained. The micro-bridge structure plays an important role in the mechanical support, thermal isolation and electrical connection for the UFPA detector,the quality of which has a direct effect on the imaging performance of the UFPA detector.

  10. 泉州湾跨海大桥海工混凝土耐久性解决方案%Research of Durability Design and Life Prediction for the Quanzhou Bay Bridge Marine Concrete Structure

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    分析了泉州湾跨海大桥混凝土结构所处的腐蚀环境特点,提出了桥梁海工混凝土耐久性解决方案。研究表明,采用低渗透高抗裂海工混凝土,提出合理的混凝土保护层最小厚度、裂缝宽度允许值,同时根据不同混凝土结构采取必要的附加防腐蚀措施,加强施工过程中混凝土质量、保护层厚度以及裂缝控制等系列措施确保桥梁混凝土的耐久性。%This paper analyzed the environmental corrosion characteristics of Quanzhou Bay Bridge concrete struc-ture and proposed solutions of the durability of bridge marine concrete.Results show that using low permeability and highly crack-resistant marine concrete,presenting proper minimum thickness of concrete cover and allowable crack width and adopting necessary additional corrosion protecting measures can improve the durability of concrete effective-ly.Meanwhile,strengthening the regulatory measures of the quality of concrete,thickness of concrete cover and crack prevention can ensure the durability of bridge concrete.

  11. Bridge Type Selection of Anyi Daifang Bridge (Ferry-Transformed Bridge)%安义县戴坊大桥(渡改桥)桥型方案选取

    Institute of Scientific and Technical Information of China (English)

    卢亚洲; 陈芳

    2013-01-01

    Under the four principles of bridge design(security, application, economics, aesthetics), the thesis optimizes the bridge site in the feasibility of the project; and compares and selects bridge program in the preliminary design phase of the Daifang Bridge; then determines the recommended program and related specific design content.%  本文按照桥梁设计的四原则(安全、适用、经济、美观),在戴坊大桥工可阶段优化了桥位选择,在初步设计阶段进行了桥型方案的比选,进而确定推荐方案和相关的具体设计内容。

  12. Analysis of Common Aerodynamic Measures for Wind Resistant Design of Long Span Bridges%大跨度桥梁抗风设计常用气动措施分析

    Institute of Scientific and Technical Information of China (English)

    胡长灿; 詹昊

    2015-01-01

    To improve the wind resistant performance of long span bridges ,the common aero‐dynamic measures and their mechanism for suppressing the vortex‐induced resonance and for im‐proving the flutter stability of the bridges are preliminarily analyzed .Since the vortex‐induced res‐onance and flutter stability of the bridges are correlated with the vortex generation and vortex drift ,the general principle of optimizing the aerodynamic measures is to improve the windward and leeward structural aerodynamic profiles in order to delay or avoid the flow separation ,reduce the separated vortex scales and impede the vortex drift paths .As regards the aerodynamic measures for suppressing the vortex‐induced vibration of the bridges ,the rounded corners and wind fairings are generally installed ,the shapes of the wind fairings are optimized and the guide vanes are in‐stalled while as regards the measures for improving the flutter stability ,the wind fairings are gen‐erally installed ,the shapes of the wind fairings are optimized and the stabilizers and aerodynamic wing plates are installed .Researches indicate that the aerodynamic performance of the long span bridges can be improved after these measures have been taken .%为提高大跨度桥梁的抗风性能,对该类桥梁抑制涡激共振和提高颤振稳定性的常用气动措施及其机理进行初步分析。桥梁涡激共振和颤振稳定性与旋涡的产生和漂移有关,因此气动优化的一般原则是改善结构迎风面和背风面的气动外形以延缓或避免流动分离、减小分离涡尺度、阻碍旋涡漂移路径。抑制桥梁涡激振动一般采用设置倒角、安装风嘴和优化风嘴形状、安装导流板等气动措施;提高桥梁颤振稳定性一般采用安装风嘴和优化风嘴形状、安装稳定板和气动翼板等气动措施。研究表明采用气动措施后,大跨度桥梁的气动性能得到改善。

  13. 云桂铁路南盘江特大桥扣锚素系统施工设计%Construction Design for Fastening-Anchoring Cable System of Nanpanjiang Bridge on Yunnan-Guangxi Railway

    Institute of Scientific and Technical Information of China (English)

    樊秋林

    2013-01-01

    南盘江特大桥是云桂铁路全线的重难点控制性工程,也是世界铁路中斜拉扣挂+分环分段组合法模注拱圈混凝土最大跨度的混凝土拱桥,主桥为单跨416m上承式钢管外包混凝土拱桥.扣锚索系统主要由扣塔、扣点、扣索、锚索及锚碇系统组,扣塔由主体5号、6号交界墩、0号段及其上部钢塔组成;扣点利用Q345B钢板在劲性骨架上弦管节点位置焊接而成;扣锚索均采用7φ5 mm(φj15.24,Rby=1 860 MPa)钢绞线束;锚碇采用岩锚和桩基承台锚碇两种形式.利用此系统进行劲性骨架单节段整体斜拉扣挂悬臂拼装、斜拉扣挂+分环分段组合法模注外包混凝土,为解决高山深谷条件下大跨度钢管外包混凝土拱桥的安全快速施工提供了参考.%As a super major bridge, Nanpanjiang Bridge is an important and difficult control project on Yunnan-Guangxi Railway. With the longest span in this kind of bridges in the world, it belongs to the concrete arch bridge with casting arch ring concrete which was erected by cable-stayed fastening-hanging method plus piecewise combination method, and its main bridge is a deck type concrete-encased steel tube arch bridge with a span of 416 meters. Its fastening-anchoring cable system was made mainly from several subsystems, including the fastening tower, fastening point, fastening cable, anchoring cable and anchorage device. The fastening tower was composed of No, 5 and No. 6 border pier, No. 0 segment and upper steel tower. Q345B steel plate was welded at the tube joint of upper chord of the stiff frame and then was taken as the fastening point. Both the fastening cable and the anchoring cable were composed of 7φ5 (φj15. 24, Rby = 1 860 MPa) steel stranded wires respectively. Two anchorage methods including rock anchorage and pile cap anchorage were employed. With this system, the construction of the stiff frame by segmental cable-stayed fastening-hanging cantilever assembling method, and

  14. Joint design and model tests of extra-long-span continuous box girder bridge composed of UHPC%超大跨径UHPC连续箱梁桥接缝设计及模型试验

    Institute of Scientific and Technical Information of China (English)

    张策; 邵旭东; 张阳

    2015-01-01

    With the precast segment cantilever method,a bracket joint between segments is proposed for the extra-long-span continuous box girder bridge composed of ultra-high performance concrete (UHPC ). The optimization analysis is conducted based on some parameters,such as the horizontal angle of bracket joint,the ratio of joint tooth block depth and height,and the ratio of joint tooth block height to beam height. The optimal ones are less than 45 ,great than 1/10, and 1/3 ~ 2/3 correspondingly. A double cantilever box girder with bracket joint is designed according to the optimization results. Combining with model tests and numerical analysis,the shear behavior of web ’s joint and the influence of diaphragm plates on the joint performance are studied. The results demonstrate that the shear behavior of web’s joint is strong,and the shear capacity of joint can be increased by intensive diaphragm plates in thin-walled box girder. The cracking strain in joint’s corner is up to 455με,and the corresponding stress is about 9. 23MPa. The results are much greater than those of the ordinary concrete joint,and the resistance cracking degree of safety approaches 1. 63.%针对超大跨径UHPC连续箱梁桥,提出悬臂拼装法施工的牛腿式UHPC节段间接缝,并对其倾角、深高比、齿梁高之比进行优化设计,得到接缝牛腿最优水平倾角为0°~45°,深高比≥1/10,齿梁高比为1/3~2/3。利用优化结果设计制作一个双悬臂梁接缝模型,采用模型试验与数值分析相结合的方法,研究薄壁箱梁拼装节段腹板接缝的抗剪性能及横隔板对腹板接缝性能的影响。静力试验的结果与数值模拟分析的结果都表明:薄壁箱梁腹板接缝抗剪性能强,密集横隔板能提高接缝抗剪承载力,接缝角趾开裂应变达到455με,相应计算应力达14.71MPa,远大于普通混凝土的接缝强度,抗裂安全度可达1.63。

  15. Floating liquid bridge charge dynamics

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  16. A strange bridge by Leonardo

    CERN Document Server

    Huylebrouck, Dirk

    2013-01-01

    On folio 855 recto of the Codex Atlanticus, Leonardo da Vinci drew three 'easily movable' bridges, but one of them is enigmatic: all 'replicas' in Leonardo museums and exhibitions come as a surprise, to say the least, to any engineer or architect whose attention is drawn to it. This is the case for models in Amboise (France), Chicago and Portland (USA), Florence (Italy) and for the one of the traveling exhibition by the Australian company 'Grande Exhibitions' that already visited 40 major cities in the world. All 'replicas' of the bridge model attributed to Leonardo have pillars standing on the deck of the bridge, while the deck is suspended by cables attached on these pillars. At first sight this problem does not catch the attention of the observer, as the bridge seems to be a mixed form of a beam and a suspension bridge, but it was not overlooked by my colleague architect-engineer Dr. Laurens Luyten (Gent, Belgium). Yet, after a TV-interview in Brussels so much pressure was exerted by some of the museum col...

  17. Academic Wholism: Bridging the Gap between High School and College

    Science.gov (United States)

    Giuliano, Barbara; Sullivan, Judith

    2007-01-01

    Without adequate reading comprehension, writing proficiency, math competency, and critical thinking skills, students pursuing higher education are vulnerable to failure. An environmental Science course built around academic wholism is the focus of a summer program designed to bridge the gap between high school and college. Students self-reflect…

  18. Evacuation of mixed populations from trains on bridges

    DEFF Research Database (Denmark)

    Kindler, C.; Sørensen, J.G.; Dederichs, A.S.

    2012-01-01

    An understanding of human evacuation dynamics and performance are important when designing complex buildings such as bridges and when applying performance-based codes in order to reduce the risk of exposing occupants to critical conditions in case of fire. The majority of previous studies deal wi...

  19. Silicone polymer waveguide bridge for Si to glass optical fibers

    Science.gov (United States)

    Kruse, Kevin L.; Riegel, Nicholas J.; Middlebrook, Christopher T.

    2015-03-01

    Multimode step index polymer waveguides achieve high-speed, (bridge for Si to glass optical fibers can be implemented using silicone polymers at 1310 nm. Fabricated and measured prototype devices with modeling and simulation analysis are reported for a 12 member 1-D tapered PWG. Recommendations and designs are generated with performance factors such as numerical aperture and alignment tolerances.

  20. Bridging history and social psychology

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre; Yamamoto, Koji

    2012-01-01

    This special issue aims to bridge history and social psychology by bringing together historians and social psychologists in an exercise of reading and learning from each other’s work. This interdisciplinary exercise is not only timely but of great importance for both disciplines. Social...... hand historians can enhance their analysis of historical sources by drawing upon the conceptual tools developed in social psychology. They can “test” these tools and contribute to their validation and enrichment from completely different perspectives. Most important, as contributions to this special......-traditionalized societies—a distinction that lies at the heart of many social psychology accounts of the world we live in. The present editorial will introduce and consider this act of bridging history and social psychology by focusing on three main questions: What is the bridge made of? How can the two disciplines...

  1. Essential Analysis on Integrated Design of Layout Plan and installation Drawing of Overhead Contact System in Conjoint Section of Bridge and Tunnel%桥隧相连地段接触网平面布置与安装图结合设计要点分析

    Institute of Scientific and Technical Information of China (English)

    梁利民

    2012-01-01

    山区电气化铁路受隧道净空和桥支柱安装位置局限性等因素的影响,桥隧相连段是接触网设计的难点和关键控制部位.就160 km/h以下客货共线铁路桥隧相连地段接触网设计的几个关键控制点进行分析和探讨,主要包括接触网支柱(悬挂点)的平面布置、导线高度和坡度的控制、锚段关节和中心锚结的位置选择、设备安装位置的选择、附加导线安装方式的选择等.%Being restricted by some factors such as the tunnel clearance, positions of poles of overhead contact system (OCS) upon bridge and so on, the conjoint section of bridge and tunnel in electrified railway of mountain area is the difficult points and key points of OCS design. This paper analyzes and discusses several key control issues of OCS design of conjoint section of bridge and tunnel in mixed passenger and freight railway under 160 km/h, including mainly the layout plan of OCS poles ( suspension points) , the control of the height and slope of conductor, the selection of the overlap position, mid-point anchor position, equipment installation position, the installation ways of additive conductor, etc.

  2. Bridging UX and web development better results through team integration

    CERN Document Server

    Moffett, Jack

    2014-01-01

    The divide between UX and Web development can be stifling. Bridging UX and Web Development prepares you to break down those walls by teaching you how to integrate with your team's developers. You examine the process from their perspective, discovering tools and coding principles that will help you bridge the gap between design and implementation. With these tried and true approaches, you'll be able to capitalize on a more productive work environment. Whether you're a novice UX professional finding your place in the software industry and looking to nail down your technical skills, or a seasone

  3. Study of displacements of a bridge abutment using FEM

    Directory of Open Access Journals (Sweden)

    Wymysłowski Michał

    2016-06-01

    Full Text Available Steel sheet piles are often used to support excavations for bridge foundations. When they are left in place in the permanent works, they have the potential to increase foundation bearing capacity and reduce displacements; but their presence is not usually taken into account in foundation design. In this article, the results of finite element analysis of a typical abutment foundation, with and without cover of sheet piles, are presented to demonstrate these effects. The structure described is located over the Więceminka river in the town of Kołobrzeg, Poland. It is a single-span road bridge with reinforced concrete slab.

  4. Very High Frequency Half Bridge DC/DC Converter

    DEFF Research Database (Denmark)

    Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.

    2014-01-01

    This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all...... components in the power stage are given. The circuit has been simulated to verify the accuracy of the presented equations and an efficiency of 89% has been shown. A prototype has been implemented with self-oscillating resonant gate drives driving the switches. The prototype has been used to drive an LED...

  5. Excitation Methods for Bridge Structures

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, C.R.; Duffy, T.A.; Cornwell, P.J.; Doebling, S.W.

    1999-02-08

    This paper summarizes the various methods that have been used to excited bridge structures during dynamic testing. The excitation methods fall into the general categories of ambient excitation methods and measured-input excitation methods. During ambient excitation the input to the bridge is not directly measured. In contrast, as the category label implies, measured-input excitations are usually applied at a single location where the force input to the structure can be monitored. Issues associated with using these various types of measurements are discussed along with a general description of the various excitation methods.

  6. Bridge Number and Conway Products

    OpenAIRE

    Blair, Ryan C.

    2007-01-01

    Schubert proved that, given a composite link $K$ with summands $K_{1}$ and $K_{2}$, the bridge number of $K$ satisfies the following equation: $$\\beta(K)=\\beta(K_{1})+\\beta(K_{2})-1.$$ In ``Conway Produts and Links with Multiple Bridge Surfaces", Scharlemann and Tomova proved that, given links $K_{1}$ and $K_{2}$, there is a Conway product $K_{1}\\times_{c}K_{2}$ such that $$\\beta(K_{1}\\times_{c} K_{2}) \\leq \\beta(K_{1}) + \\beta(K_{2}) - 1$$ In this paper, we define the generalized Conway prod...

  7. Is myocardial bridging a bridge connecting to cardiovascular events?

    Institute of Scientific and Technical Information of China (English)

    LI Jian-jun

    2010-01-01

    @@ Coronary arteries and their major branches usually course on the surface of the heart in the subepicardial tissue. However, a muscle hber overlying the intramyocardial segment of an epicardial coronary artery was defined as myocardial bridging (MB), and subsequently the artery coursing within the myocardium is called a tunneled artery.

  8. Design and Analysis of Main Saddle Structure for Self-anchored Suspension Bridge with Spatial Cables%空间缆索悬索桥主鞍座结构设计与分析

    Institute of Scientific and Technical Information of China (English)

    李建慧; 李爱群; 袁辉辉; 李喜平

    2009-01-01

    以南京江心洲大桥为工程背景,对空间缆索自锚式悬索桥主鞍座的相关问题进行研究.以大型通用有限元程序为平台,采用二次开发技术,建立精细化有限元模型,在此基础上采用合理的加载模式对其进行空间受力分析,并阐述与空间主鞍座相匹配的主缆切点简化修正方法.结果表明:空间主缆在成桥状态对主鞍座横向力的作用会造成鞍槽外侧壁应力大于内侧壁的应力;主缆横向体积力会对主鞍座压紧装置和鞍体产生梯度分布的竖向挤压力;自锚式悬索桥体系转换过程中缆索的几何非线性效应显著,体现在空缆到成桥状态主缆与主鞍座空间切点位置会有较大的变化.%Based on the Jianxinzhou Bridge in Nanjing, the issues related to the main saddle of the serf-anchored suspension bridge with spatial cables were studied. Refinement finite element model was established with secondary development technology based on the platform of general finite element program, reasonable load pattern was used for its spatial mechanical analysis, and the spatial main cable tangenty point correction method which matched with the main saddle was also discussed. The result shows that (1) external lateral wall stress of saddle groove is higher than the internal wall stress because of the role of lateral force from the main cable in the ~mished bridge state; (2) horizontal volume force of the main cable can generate a gradient distribution of vertical extrusion pressure on the saddle clamping device and the main saddle body; (3) the geometric nonlinear effect of self-anchored suspension bridge cable system in the constroction process is significant, which reflects from that the spatial tangent point position of main cable with main saddle changes a lot from free cable to finished cable state.

  9. Evacuation of mixed populations from trains on bridges

    DEFF Research Database (Denmark)

    Kindler, C.; Sørensen, J.G.; Dederichs, A.S.

    2012-01-01

    An understanding of human evacuation dynamics and performance are important when designing complex buildings such as bridges and when applying performance-based codes in order to reduce the risk of exposing occupants to critical conditions in case of fire. The majority of previous studies deal...... with the evacuation behavior of abled bodied homogeneous groups. Hence, a significant part of the population is poorly described such as are people with impairments which are about 10%-21% of the world's population, furthermore elderly people, giving an additional 10% and 20% of the population are aged below 15 years....... The discussion of "equal access" is only followed slowly by the demand on "equal egress". However, the passengers on trains on bridges are rarely homogeneous mixture. At the same time equal egress is far from assured today. In this paper the evacuation of mixed populations from trains on bridges are considered...

  10. Scale-Bridging Model Development for Coal Particle Devolatilization

    CERN Document Server

    Schroeder, Benjamin B; Smith, Philip J; Fletcher, Thomas H; Packard, Andrew; Frenklach, Michael; Hegde, Arun; Li, Wenyu; Oreluk, James

    2016-01-01

    When performing large-scale, high-performance computations of multi-physics applications, it is common to limit the complexity of physics sub-models comprising the simulation. For a hierarchical system of coal boiler simulations a scale-bridging model is constructed to capture characteristics appropriate for the application-scale from a detailed coal devolatilization model. Such scale-bridging allows full descriptions of scale-applicable physics, while functioning at reasonable computational costs. This study presents a variation on multi-fidelity modeling with a detailed physics model, the chemical percolation devolatilization model, being used to calibrate a scale-briding model for the application of interest. The application space provides essential context for designing the scale-bridging model by defining scales, determining requirements and weighting desired characteristics. A single kinetic reaction equation with functional yield model and distributed activation energy is implemented to act as the scal...

  11. Seismic Retrofitting of an Existing Steel Railway Bridge by Fluid Viscous Dampers

    Science.gov (United States)

    Gangopadhyay, Avijit; Ghosh, Aparna Dey

    2016-06-01

    There are over a lakh of bridges in the Indian Railways, many of which have become seismically deficient, either through aging or due to inadequate seismic design considerations. The extensive damage of bridges all over the world in recent earthquakes has propelled significant advancement in earthquake protection and retrofitting of bridges. Amongst various passive control systems that are reliable as well as cost-effective, Fluid Viscous Dampers (FVDs) are proving to be successful in bridge vibration control. Orificed FVDs, commercially available as Taylor Devices, have already been successfully installed in several bridges worldwide. However, there has been no such application or study related to Indian railway bridges. In this paper, an existing thirty years' old railway bridge in Jharkhand, India, has been analyzed in SAP2000v14 considering reduced stiffness and found deficient when subjected to spectrum-compatible accelerograms. Subsequent retrofitting of the bridge superstructure with FVDs has been carried out and the results indicate substantial reductions in the responses of the bridge deck.

  12. Modelling the Flow Structure in Local Scour Around Bridge Pier

    Directory of Open Access Journals (Sweden)

    Usman Ghani

    2014-04-01

    Full Text Available Bridge pier scouring is an important issue of any bridge design work. If it is not taken into account properly, then results will be disastrous. A number of bridges have failed due to clear water local scouring of piers. This research paper presents a numerical model study in which an attempt has been made to explore the flow variables which exist in and around a scoured bridge pier. A finite volume based model of bridge pier was developed using 3D (Three Dimensional numerical code FLUENT and GAMBIT. After validation process, different discharge values were considered and its impact on three dimensional characteristics of flow such as stream-wise velocities on longitudinal and transverse sections, turbulance circulation cells, and boundary shear stresses was investigated. It was observed that increasing the discharge results in more turbulance around the pier on its downstream side and turbulence properties are intensified in such a situation. However, the primary velocities on the downstream side remain almost unchanged. The results have been presented in the form of contours, vector of primary velocities and x-y plots of bed shear stresses. This study can be used for enhanced understanding of flow features and improvement of formulae for prediction of scour holes around piers

  13. Seismic Response Analysis of Continuous Multispan Bridges with Partial Isolation

    Directory of Open Access Journals (Sweden)

    E. Tubaldi

    2015-01-01

    Full Text Available Partially isolated bridges are a particular class of bridges in which isolation bearings are placed only between the piers top and the deck whereas seismic stoppers restrain the transverse motion of the deck at the abutments. This paper proposes an analytical formulation for the seismic analysis of these bridges, modelled as beams with intermediate viscoelastic restraints whose properties describe the pier-isolator behaviour. Different techniques are developed for solving the seismic problem. The first technique employs the complex mode superposition method and provides an exact benchmark solution to the problem at hand. The two other simplified techniques are based on an approximation of the displacement field and are useful for preliminary assessment and design purposes. A realistic bridge is considered as case study and its seismic response under a set of ground motion records is analyzed. First, the complex mode superposition method is applied to study the characteristic features of the dynamic and seismic response of the system. A parametric analysis is carried out to evaluate the influence of support stiffness and damping on the seismic performance. Then, a comparison is made between the exact solution and the approximate solutions in order to evaluate the accuracy and suitability of the simplified analysis techniques for evaluating the seismic response of partially isolated bridges.

  14. Preliminary study to facilitate smart structure systems in bridge girders

    Science.gov (United States)

    Kirkpatrick, Thomas C.; Peterson, Danford O.; Rossi, Peter J.; Ray, Laura R.; Livingston, Richard A.

    1999-05-01

    Sensors are currently available and used to monitor structural performance and loads incurred by bridges already in service. However, there has been limited research concerning the stresses that steel bridge girders endure during transport from the manufacturer to the job site and during the installation process. This paper reports the measured stresses on steel bridge girders during transportation from Lancaster, PA to Hanover, NH and during construction of the Ledyard Bridge on the New Hampshire - Vermont border. Two different monitoring system were developed for this data acquisition in a mobile environment. The first, a fiber optic strain monitoring system, utilizing Bragg grating technology. The second utilized an electrical- resistive foil strain gage network, in conjunction with wireless telemetry equipment. Together, these two systems formed a smart structure system for monitoring bridge girders while confirming the accuracy of data gathered through redundancy. Result conclusively demonstrated for the first time, that stresses in beams during transportation are significant and approach the factor of safety margin in girder design.

  15. US-Korea collaborative research for bridge monitoring test beds

    Science.gov (United States)

    Yun, C. B.; Sohn, H.; Lee, J. J.; Park, S.; Wang, M. L.; Zhang, Y. F.; Lynch, J. P.

    2010-04-01

    This paper presents an interim report on an international collaborative research project between the United States and Korea that fundamentally addresses the challenges associated with integrating structural health monitoring (SHM) system components into a comprehensive system for bridges. The objective of the project is to integrate and validate cutting-edge sensors and SHM methods under development for monitoring the long-term performance and structural integrity of highway bridges. A variety of new sensor and monitoring technologies have been selected for integration including wireless sensors, EM stress sensors and piezoelectric active sensors. Using these sensors as building blocks, the first phase of the study focuses on the design of a comprehensive SHM system that is deployed upon a series of highway bridges in Korea. With permanently installed SHM systems in place, the second phase of the study provides open access to the bridges and response data continuously collected as an internal test-bed for SHM. Currently, basic facilities including Internet lines have been constructed on the test-beds, and the participants carried out tests on bridges on the test road section owned by the Korea Expressway Corporation (KEC) with their own measurement and monitoring systems in the local area network environment. The participants were able to access and control their measurement systems by using Remote Desktop in Windows XP through Internet. Researchers interested in this test-bed are encouraged to join in the collaborative research.

  16. Centrifuge modeling of rocking-isolated inelastic RC bridge piers

    OpenAIRE

    Loli, Marianna; Knappett, Jonathan A; Brown, Michael J.; Anastasopoulos, Ioannis; GAZETAS, George

    2014-01-01

    Experimental proof is provided of an unconventional seismic design concept, which is based on deliberately underdesigning shallow foundations to promote intense rocking oscillations and thereby to dramatically improve the seismic resilience of structures. Termed rocking isolation, this new seismic design philosophy is investigated through a series of dynamic centrifuge experiments on properly scaled models of a modern reinforced concrete (RC) bridge pier. The experimental method reproduces th...

  17. Instability of the capillary bridge

    Science.gov (United States)

    Pare, Gounseti; Hoepffner, Jerome

    2014-11-01

    Capillary adhesion is a physical mechanism that maintains two bodies in contact by capillarity through a liquid ligament. The capillary bridge is an idealization of this capillary adhesion. In this study we first focus on the classical case of the stability of the capillary bridge. Secondly we study a slightly more complex configuration, imagining a flow in the capillary bridge as in the case of the dynamics of the neck of a liquid ligament, in its withdrawal under the effect of capillarity. Inspired by the experiments on soap films of Plateau, the configuration analyzed consists of an initially axisymmetric, mass of fluid held by surface tension forces between two parallel, coaxial, solid pipes of the same diameter. The results presented are obtained by numerical simulations using the free software, Gerris Flow Solver. We first focus on the capillary Venturi. In the static configuration the stability diagram of the capillary bridge obtained is in perfect agreement with the results of Lev A. Slobozhanin. In the dynamic case we develop a matlab code based on the one dimensional equations of Eggers and Dupont. The comparison of the bifurcation diagram obtained and the numerical simulations shows a good agreement.

  18. Intercellular bridges in vertebrate gastrulation.

    Directory of Open Access Journals (Sweden)

    Luca Caneparo

    Full Text Available The developing zebrafish embryo has been the subject of many studies of regional patterning, stereotypical cell movements and changes in cell shape. To better study the morphological features of cells during gastrulation, we generated mosaic embryos expressing membrane attached Dendra2 to highlight cellular boundaries. We find that intercellular bridges join a significant fraction of epiblast cells in the zebrafish embryo, reaching several cell diameters in length and spanning across different regions of the developing embryos. These intercellular bridges are distinct from the cellular protrusions previously reported as extending from hypoblast cells (1-2 cellular diameters in length or epiblast cells (which were shorter. Most of the intercellular bridges were formed at pre-gastrula stages by the daughters of a dividing cell maintaining a membrane tether as they move apart after mitosis. These intercellular bridges persist during gastrulation and can mediate the transfer of proteins between distant cells. These findings reveal a surprising feature of the cellular landscape in zebrafish embryos and open new possibilities for cell-cell communication during gastrulation, with implications for modeling, cellular mechanics, and morphogenetic signaling.

  19. Parametric Study on Dynamic Response of Fiber Reinforced Polymer Composite Bridges

    Directory of Open Access Journals (Sweden)

    Woraphot Prachasaree

    2015-01-01

    Full Text Available Because of high strength and stiffness to low self-weight ratio and ease of field installation, fiber reinforced polymer (FRP composite materials are gaining popularity as the materials of choice to replace deteriorated concrete bridge decks. FRP bridge deck systems with lower damping compared to conventional bridge decks can lead to higher amplitudes of vibration causing dynamically active bridge deck leading serviceability problems. The FRP bridge models with different bridge configurations and loading patterns were simulated using finite element method. The dynamic response results under varying FRP deck system parameters were discussed and compared with standard specifications of bridge deck designs under dynamic loads. In addition, the dynamic load allowance equation as a function of natural frequency, span length, and vehicle speed was proposed in this study. The proposed dynamic load allowance related to the first flexural frequency was presented herein. The upper and lower bounds’ limits were established to provide design guidance in selecting suitable dynamic load allowance for FRP bridge systems.

  20. Evaluation of Dynamic Load Factors for a High-Speed Railway Truss Arch Bridge

    Directory of Open Access Journals (Sweden)

    Ding Youliang

    2016-01-01

    Full Text Available Studies on dynamic impact of high-speed trains on long-span bridges are important for the design and evaluation of high-speed railway bridges. The use of the dynamic load factor (DLF to account for the impact effect has been widely accepted in bridge engineering. Although the field monitoring studies are the most dependable way to study the actual DLF of the bridge, according to previous studies there are few field monitoring data on high-speed railway truss arch bridges. This paper presents an evaluation of DLF based on field monitoring and finite element simulation of Nanjing DaShengGuan Bridge, which is a high-speed railway truss arch bridge with the longest span throughout the world. The DLFs in different members of steel truss arch are measured using monitoring data and simulated using finite element model, respectively. The effects of lane position, number of train carriages, and speed of trains on DLF are further investigated. By using the accumulative probability function of the Generalized Extreme Value Distribution, the probability distribution model of DLF is proposed, based on which the standard value of DLF within 50-year return period is evaluated and compared with different bridge design codes.