Sample records for bridge design

  1. General framework for bridge life cycle design

    Junhai MA; Airong CHEN; Jun HE


    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. New Philosophy in Steel Bridge Design and Frabrication

    Henkle, David


    The foremost parameters in the design of any structure are safety and cost. The SEBD (simplified economical bridge design) concept meets and exceeds all conditions of safety but with an added benefit of cost savings over more conventional design procedures for steel bridges. Comparative analysis indicates that cost saving as much as 10 percent of the bridge cost can be realized. Learn about SEBD and how you can apply it to steel bridge design and fabrication. Contact InformationTele: 574-2...

  3. Research on Fairway Width Design in Curved Bridge Waters Channel

    Chi Hong-Fu


    Full Text Available Bridge construction can promote economic development but if the bridge layout is unreasonable, it would hinder ship’s safety navigation in the bridge area. There is little reference for fairway width design about curved bridge channel in 〈〈inland river navigation standards〉〉 of China. In this study, a fairway width design method in curved bridge channel was put forward by taking into account the scope of turbulent scope of pier, ship’s track width, drifting distance due to wind, drifting distance due to current, the scope of ship’s safety field and additional width in curved channel. The fairway width design concept for curved bridge channel presented in this studyit may provide reference for bridge design and other fairway layout.

  4. The Influence of the Recommended LRFD Guidelines for the Seismic Design of Highway Bridges on Virginia Bridges

    Widjaja, Matius Andy


    THE INFLUENCE OF THE RECOMMENDED LRFD GUIDELINES FOR THE SEISMIC DESIGN OF HIGHWAY BRIDGES ON VIRGINIA BRIDGES by Matius A. Widjaja Committee Chairwoman: Prof. Carin Roberts-Wollmann Civil Engineering (ABSTRACT) The influence of the recommended LRFD Guidelines for the seismic design of highway bridges in Virginia was investigated by analyzing two existing bridges. The first bridge has prestressed concrete girders and is located in the Richmond area. The second bridge has...

  5. A modular steel freeway bridge: design concept and earthquake resistance.

    Wattenburg, W H; McCallen, D B; Murray, R C


    A modular multilane steel freeway bridge has been constructed from surplus railroad flatcar decks. It can be erected on-site in a few days' time. It has been built and static-load tested for emergency freeway bridge repair. This inexpensive modular bridge may also have broad application around the world for low-cost bridges in areas where funds are limited. On the basis of static-load testing performed by the California Department of Transportation and computer dynamic analysis, this simple modular-design concept has the potential of providing a strong bridge that can withstand the severe aftershocks expected immediately after a major earthquake. PMID:17814794

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

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


    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...

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

    Bakht, Baidar


    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...

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

    Oguz Gunes


    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.

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

    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

  10. Research on Multidisciplinary Optimization Design of Bridge Crane

    Tong Yifei; Ye Wei; Yang Zhen; Li Dongbo; Li Xiangdong


    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 c...

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

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


    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.

  12. Scientific Collaborations: principles of WikiBridge Design

    Leclercq, Eric


    Semantic wikis, wikis enhanced with Semantic Web technologies, are appropriate systems for community-authored knowledge models. They are particularly suitable for scientific collaboration. This paper details the design principles ofWikiBridge, a semantic wiki.

  13. Optimum design of concrete cable-stayed bridges

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


    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.

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

    Spasojevic, Ana


    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. ...

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

    Fujino, Yozo; Tanaka, Hiroshi


    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...

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

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


    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...

  17. Research on Multidisciplinary Optimization Design of Bridge Crane

    Tong Yifei


    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.

  18. CPT in bridge foundation and embankment design

    Braaten, Anne; Oset, Frode; Vaslestad, Jan


    The cone penetration test (CPT) has proved to be a valuable tool in obtaining design parameters for foundations especially in silty and sandy soils, and even in clay. This paper is submitted to the international symposium CPT'95 in Linkjøping, Sweden. It shows a few cases where CPT interpretations are compared with laboratory test results, and design calculations based on CPTs are compared with field observations and other design methods.


    Wang Min; Wu Shunjun; Su Tao


    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.

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

    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

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

    杨成峰; 邱白


    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。

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

    FAN Lichu


    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.

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


    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.

  4. Reliability evaluation of axially loaded steel members design criteria in AASHTO LRFD bridge design code

    Reliability based structural design insures a uniformly designed structure, in terms of safety. By considering an adequate reliability index (or probability of failure) for different parts of a structure, a reasonable balance between cost and safety of the structure can be achieved. In this study, the reliability of steel tension and compression members designed with AASHTO LRFD bridge design specifications (2007) is evaluated. These members are prevalent in different types of truss or arch bridges. Various conditions such as redundancy, ductility and importance of the bridge are taken into account by changing the load modification factor, η. To include the effect of the span length, a variable ratio of dead load to total load is considered. Current load factors in AASHTO LRFD code are accepted due to their verification in a comprehensive study for reliability of girder-type bridges. Furthermore, load and resistance distribution models are chosen based on the latest existing experimental data. The Monte Carlo simulation technique with randomly generated samples is applied in numerical calculations. For tension members, analysis results show relatively high reliability indices in yielding design, while having slightly low reliabilities for the fracture mode. For fracture design of steel tension members, an increase in vehicular dynamic load allowance (IM) from 33% to 75% is suggested to insure a safer behavior. Also, it is shown that the resistance factor for yielding of gross section, φy, can be increased from 0.95 to 1.00 while maintaining enough safety for designed tension members. In addition, obtained reliability curves for steel compression members show a safe behavior of designed compression members with conservative response in some cases. More results and plotted curves are discussed in detail and possible adjustments in code criteria are presented in this paper

  5. Improvement on design analyses of composite steel-concrete bridges using elaborate finite element methods

    Jaturong Sanguanmanasak


    Full Text Available In this paper, three-dimensional finite element analysis of composite steel-concrete bridges is performed to simulate theactual bridge behavior. The accuracy of the model is verified against the results acquired from a field test. Thai trucks are loaded at possible locations of the bridge in order to obtain the maximum stresses on the bridge. The influences of concrete barriers, the displacement of bridge piers, and the Young’s modulus of concrete are then discussed, to reveal the actual behavior of the steel-concrete composite bridge. The reactions at the bearings on the bridge piers are also evaluated and discussed in this conjunction. Good agreement is obtained between the models and loading tests to show that the finite element model can aid engineers in design practices.

  6. Structural behavior and design criteria for bridge strengthening by tied arch. Comparison with network arch bridges

    Valenzuela, Matías A.; Casas Rius, Joan Ramon


    This study focuses on a new strengthening method of continuous bridges with several spans that present extensive damage in their foundation/piers due to scour and erosion. The method consists on the construction of a new upper steel arch with a network hanger's arrangement over the original deck with the aim to hang the existing deck to the new arch. The deck is acting as a tie in the new structural configuration. This allows to remove the damaged foundations/piers, deriving on an arch bridge...

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

    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

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

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


    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.

  9. On Reliability Based Optimal Design of Concrete Bridges

    Thoft-Christensen, Palle

    In recent years important progress has been made in assessment of the lifetime behaviour of concrete bridges. Due to the large uncertainties related to the loading and the deterioration of such bridges, an assessment based on stochastic modelling of the significant parameters seems to be only...... relevant modelling. However, a great number of difficulties are involved in the modelling. The main purpose of this paper is to give an overview of areas where more research is needed and in some cases propose solutions....

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

    Du, Guangli; Karoumi, Raid


    Railway bridges currently encounter the challenges of increasing the load capacity while the environmental sustainability should be achieved. However, it has been realised that the environmental assessment of railway bridges has not been integrated into the decision-making process, the standard...... guideline and criterion is still missing in this field. Therefore, the implementation of life cycle assessment (LCA) method is introduced into railway bridges. This article provides a systematic bridge LCA model as a guideline to quantify the environmental burdens for the railway bridge structures. A...... 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...

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



    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。

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

    Gligorijević Milan


    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.

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

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


    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.

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

    Bertelsen, Olav Wedege; Kramp, Gunnar


    In this position paper we discuss, in terms of the concept of boundary objects, how a mobile application, the, 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....

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

    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 desi...

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

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


    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 ...

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

    Ji Lin


    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.

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



    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.

  19. Designing a second language bridging course for university students

    Carol A. Puhl


    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

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

    Ozbulut, Osman E.; Hurlebaus, Stefan


    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.

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



    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.

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

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


    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

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

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


    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.

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

    Yan Jukao; Han Lei; Zhao Yi; Peng Tianbo


    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.

  5. Designing a bridge for consciousness: are criteria for a unification of approaches feasible?

    Miller, D W


    Different intrinsic rules of functioning for body and mind are overemphasized by the mutually exclusive methods of investigation in both consciousness and the sciences. Classical science, alternative and complementary healing, quantum physics, and metaphysics all take drastically different approaches to consciousness research. A bridge is needed to restore the conceptual unity of mind-body. However, the construction of such a bridge paradoxically must rely on consciousness for information. The construction company (Consciousness, Inc.) therefore becomes means and end in the design of the bridge. This piece argues that the methods of each discipline contain research tools and resources to create a bridge that satisfies a unified multidimensional and multidisciplinary conception. The piece further suggests that the framework of the bridge must place consciousness as a partner to physiology in the evolutionary trajectory of life, since problems of survival are a primary consideration in the activity of both. Finally, the piece develops six criteria by which to evaluate the effectiveness of any construction design. PMID:10835764

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

    Jonge, de, B.; Valk, van der, L.J.M.


    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 they develop an empirically grounded methodology for planning and design. The process of theory building is part of a process of methodical reflection on best and worst practices. It focuses on an ana...

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

    Li Jianzhong; Peng Tianbo; Xu yan


    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.

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

    Halding, Philip Skov


    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....

  9. Memetic Algorithm Approach to Designing Precast-Prestressed Concrete Road Bridges with Steel Fiber Reinforcement

    Martí Albiñana, José Vicente; Yepes Piqueras, Víctor; Gonzalez Vidosa, Fernando


    This paper describes the influence of steel fiber-reinforcement on the design of cost-optimized, prestressed concrete, precast road bridges, with a double U-shaped crosssection and isostatic spans. A memetic algorithm with variable-depth neighborhood search is applied to the economic cost of these structures at different stages of manufacturing, transportation, and construction. The problem involved 41 discrete design variables for the geometry of the beam and the slab, materials in the two e...

  10. Design and fabrication of indium phosphide air-bridge waveguides with MEMS functionality

    Ng, Wing; Podoliak, Nina; Horak, Peter; Wu, Jiang; Liu, Huiyun; Stewart, Will; Kenyon, Anthony J.


    We present the design and fabrication of a dual air-bridge waveguide structure integrated with MEMS functionality. The structure is designed to function as a tunable optical buffer for telecommunication application. The optical buffer structure is based on two parallel waveguides made of high refractive index material with subwavelength dimensions. They are suspended in air, and are separated by a sub-micron air gap. Due to the fact that the size of the waveguides is much smaller than the wav...

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

    Koss, Holger


    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...... influences the accretion of ice to an extent that the aerodynamic forces differ significantly amongst the designs. The experiments were conducted in a wind tunnel facility capable amongst others to simulate in-cloud icing conditions....

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

    Raymond E. Levitt


    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.

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

    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....

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

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


    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.

  15. D0 Silicon Upgrade: End Calorimeter Transfer Bridge Design and Installation Procedures

    elevated to the level of the transfer bridge. The elevation process is the same as that used for the CC installation. When the correct elevation is attained the transporter extensions are positioned and fastened to the transporter on the south side. Static column supports will be added underneath the transporter to minimize deflections as the NEC is rolled off. The carriage extensions are now put in place and the Hilman rollers transferred into position under the extensions. The NEC is now ready to be pulled off of the transporter and onto the transfer bridge. Again using the Cyl. and chain mechanism, with the anchor point attached to the transporter extension on the north sidewalk, pull the NEC completely off of the transporter and onto the transfer bridge. Once the NEC is on the transfer bridge a rearrangement of equipment must be done. The transporter extension on the north sidewalk is decoupled from the transfer bridge and moved against the wall of the fixed counting area. The transporter extension at the south end of the transporter is removed, the transporter is decoupled from and moved to the north side of the transfer bridge. The transporter is supported from the floor at an elevation equal to the transfer bridge and coupled to it. The transporter extension is fastened to the north end of the transporter. The movement of the NEC now continues until it is back on the transporter. At this time the transfer bridge, concrete shield blocks and steel plates in the pit are removed. The detector is moved back to its normal parked position(cable bridge up). The NEC is lowered to the sidewalk (reverse of elevation procedure). Welding of the heads is then finished prior to final installation on the center beam. The final installation is identical to the CC installation, using all the same equipment. The finite element analysis of the transfer bridge design was done by Kay Weber of the Accelerator Mechanical Support Group.

  16. A predictive Bayesian approach to the design and analysis of bridging studies.

    Gould, A Lawrence; Jin, Tian; Zhang, Li Xin; Wang, William W B


    Pharmaceutical product development culminates in confirmatory trials whose evidence for the product's efficacy and safety supports regulatory approval for marketing. Regulatory agencies in countries whose patients were not included in the confirmatory trials often require confirmation of efficacy and safety in their patient populations, which may be accomplished by carrying out bridging studies to establish consistency for local patients of the effects demonstrated by the original trials. This article describes and illustrates an approach for designing and analyzing bridging studies that fully incorporates the information provided by the original trials. The approach determines probability contours or regions of joint predictive intervals for treatment effect and response variability, or endpoints of treatment effect confidence intervals, that are functions of the findings from the original trials, the sample sizes for the bridging studies, and possible deviations from complete consistency with the original trials. The bridging studies are judged consistent with the original trials if their findings fall within the probability contours or regions. Regulatory considerations determine the region definitions and appropriate probability levels. Producer and consumer risks provide a way to assess alternative region and probability choices. [Supplemental materials are available for this article. Go to the Publisher's online edition of the Journal of Biopharmaceutical Statistics for the following free supplemental resource: Appendix 2: R code for Calculations.]. PMID:22946940

  17. Design of prestressed concrete precast road bridges with hybrid simulated annealing

    Martí Albiñana, José Vicente; Gonzalez Vidosa, Fernando; Yepes Piqueras, Víctor; Alcalá González, Julián


    This paper describes one approach to the analysis and design of prestressed concrete precast road bridges, with double U-shaped cross-section and isostatic spans. The procedure used to solve the combinatorial problem is a variant of simulated annealing with a neighborhood move based on the mutation operator from the genetic algorithms (SAMO). This algorithm is applied to the economic cost of these structures at different stages of manufacturing, transportation and construction. The problem in...

  18. Designing the optimum watch keeping schedule for a passenger vessel bridge team

    Heikkilä, Mikko


    A well-designed watch schedule is the backbone of the working environment for the bridge team on board ships. The rhythm on passenger vessels is quite different when compared to cargo ships: there are more drills and more safety related work. Actual watchkeeping is also different due to more internal communication and alarm management. Understanding the unique features is paramount when setting up the watch system. Sleep deprivation and fatigue causes health issues for the crewmembers but ...

  19. Designing the optimum watchkeeping schedule for a passenger vessel bridge team

    Heikkilä, Mikko


    A well-designed watch schedule is the backbone of the working environment for the bridge team on board ships. The rhythm on passenger vessels is quite different when compared to cargo ships: there are more drills and safety related work. Actual watchkeeping is also different due to more internal communication and alarm management. Understanding the unique features is paramount when setting up the watch system. Sleep deprivation and fatigue causes health issues for the crewme...


    Francis, Charles; Nicolaysen, Anna Marie; Morse, Suzanne; Breland, Tor Arvid; Lieblein, Geir


    Bridging the large gap between science and experience of farmers is a crucial focus for educators who are intent on developing learning programs featuring phenomenology and practical experiences. Agroecology is emerging as an integrative and holistic approach to study agricultural and food systems. Understanding lessons learned from indigenous systems and the ecological principles on which they are built, focusing on the uniqueness of place in design and practice of farming, shifting from a d...

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

    Carnaby, Sarah


    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...

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

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


    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,...

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

    Husemoen, Mette Suzanne


    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.

  4. Design and Modeling of Five Level PWM Hybrid H-Bridge Multilevel Converter

    P.Surendra Babu,Dr. B V. Sanker Ram


    Full Text Available The concept of multilevel inverters introduced about 20 years ago entails performing power conversion in multiple voltage steps to obtain improved power quality, lower switching losses, better electromagnetic compatibility, and higher voltage capability. The benefits are especially clear for medium-voltage drives in industrial applications and are being considered for future naval ship propulsion systems. Several topologies for multilevel inverters have been proposed over the years; the most popular cascaded H-bridge apart from other multilevel inverters is the capability of utilizing different dc voltages on the individual H-bridge cells which results in splitting the power conversion amongst higher-voltage lower-frequency and lower-voltage higher-frequency inverters. Considering the cascaded inverter to be one unit, it can be seen that a higher number of voltage levels are available for a given number of semiconductor devices. In this paper a Novel 5 level Hybrid H-Bridge is proposed. Considering the system as separate inverters, the cascaded design can be regarded as a combination of a bulk power (highervoltage inverter and a conditioning (lower-power inverter. In this paper, the design procedure for single cell based on cost and losses optimization is carried out. The selection of a single cell is based on SSOA (safe operating Area and Thermal Rating .The selection of capacitor and heat sink is also carried out. A SIMULINK based model is developed and Simulation results are presented.

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

    Ding Lei; Shan Hongwei; Zhou Qing; Zheng Benhui


    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.

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

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


    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. PMID:26276996

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

    Jiancheng YU; Hao TONG; Wei HUANG


    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.

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



    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。

  9. Development of an optimized procedure bridging design and structural analysis codes for the automatized design of the SMART

    In this report, an optimized design and analysis procedure is established to apply to the SMART (System-integrated Modular Advanced ReacTor) development. The development of an optimized procedure is to minimize the time consumption and engineering effort by squeezing the design and feedback interactions. To achieve this goal, the data and information generated through the design development should be directly transferred to the analysis program with minimum operation. The verification of the design concept requires considerable effort since the communication between the design and analysis involves time consuming stage for the conversion of input information. In this report, an optimized procedure is established bridging the design and analysis stage utilizing the IDEAS, ABAQUS and ANSYS. (author). 3 refs., 2 tabs., 5 figs

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

    Schiavone, Marco; Fiume, Giuseppe; Caivano, Antonella; de Laurentiis, Annamaria; Falcone, Cristina; Masci, Francesca Fasanella; Iaccino, Enrico; Mimmi, Selena; Palmieri, Camillo; Pisano, Antonio; Pontoriero, Marilena; Rossi, Annalisa; Scialdone, Annarita; Vecchio, Eleonora; Andreozzi, Concetta; Trovato, Maria; Rafay, Jan; Ferko, Boris; Montefiori, David; Lombardi, Angela; Morsica, Giulia; Poli, Guido; Quinto, Ileana; Pavone, Vincenzo; de Berardinis, Piergiuseppe; Scala, Giuseppe


    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. PMID:22754323

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

    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

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

    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

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

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


    potential, being compatible with batch micro- and nanofabrication techniques. For low-frequency magnetic field detection, sensors based on the planar Hall effect, especially planar Hall effect bridge (PHEB) sensors, show promising performance given their inherent low-field linearity, limited hysteresis and...... 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...

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

    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

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

    Guido Poli


    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.

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



    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.

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

    Acar, Yalda; Jingstål, Pontus


    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...

  18. Cable Supported Bridges

    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...

  19. A survey of Wien bridge-based chaotic oscillators: Design and experimental issues

    This paper presents a comparative study on design and implementation of Wien type chaotic oscillators. By making a collection of almost all Wien bridge-based chaotic circuits, we have investigated these oscillators in terms of chaotic dynamics, circuit structures, active building blocks, nonlinear element structures and operating frequency by using PSpice simulations and laboratory experiments. In addition to this comparative investigation, we present our two basic experimental contributions to referred implementations. While the first of our experimental contributions consists of the experimentally implementation of CFOA-based Chua's circuit modified for very high chaotic oscillations, the scope of the second is to experimentally implement a Wien type high frequency chaos generator, which has the diode-inductor composite, in the inductorless form by using CFOA-based synthetic inductor

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

    Zhang, Dao; He, Yu; Tang, Junkai


    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

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

    Shina Caroline Lynn Kamerlin


    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.

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

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


    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

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

    Lan, Cheng


    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...

  4. Design of a single-track railway network arch bridge : According to the Eurocodes

    Varennes, Maxime


    A constant research of more ecological and efficient structures has enabled bridges to be more innovative through the years. Nowadays, as the need is greater than ever, a new kind of bridge is expanding in the entire world: the network arch bridges. The concept was developed by professor and engineer Per Tveit in 1955 and has been improved since then. But it is only for 10 years that many bridges of this sort have been built. The aim of the thesis is to investigate the structural behavior of ...

  5. Design and analysis of the tracker bridge for the Hobby-Eberly Telescope wide-field upgrade

    Worthington, Michael S.; Mollison, Nicholas T.; Soukup, Ian M.; Zierer, Joseph J.; Good, John M.; Nichols, Steven P.


    A large structural weldment has been designed to serve as the new star tracker bridge for the Wide Field Upgrade to the Hobby-Eberly Telescope at McDonald Observatory in support of the Hobby-Eberly Telescope Dark Energy Experiment‡. The modeling approach, analysis techniques and design details will be of interest to designers of large structures where stiffness is the primary design driver. The design includes detailed structural analysis using finite element models to maximize natural frequency response and limit deflections and light obscuration. Considerable fabrication challenges are overcome to allow integration of precision hardware required for positioning the corrector optics to a precision of less than 5 microns along the 4-meter travel range. Detailed descriptions of the bridge geometry, analysis results and challenging fabrication issues are discussed.

  6. PCI-VME bridge device driver design of a high-performance data acquisition and control system on LINUX

    Data acquisition and control is an important part of nuclear electronic and nuclear detection application in HEP. The key method has been introduced for designing LINUX device driver of PCI-VME bridge device based on realized by authors' data acquisition and control system

  7. PCI-VME bridge device driver design of a high-performance data acquisition and control system on LINUX

    Data Acquisition and Control is an important part of Nuclear Electronic and Nuclear Detection application in HEP. The key methods are introduced for designing LINUX Device Driver of PCI-VME Bridge Device based on the realized Data Acquisition and Control System

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

    张红星; 刘德宝; 余茂峰


    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.

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

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


    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...

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



    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.

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

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


    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.

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



    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.

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

    Ruan, Xinbo


    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

  14. Design and fabrication of indium phosphide air-bridge waveguides with MEMS functionality

    Ng, Wing H.; Podoliak, Nina; Horak, Peter; Wu, Jiang; Liu, Huiyun; Stewart, William J.; Kenyon, Anthony J.


    We present the design and fabrication of a dual air-bridge waveguide structure integrated with MEMS functionality. The structure is designed to function as a tunable optical buffer for telecommunication application. The optical buffer structure is based on two parallel waveguides made of high refractive index material with subwavelength dimensions. They are suspended in air, and are separated by a sub-micron air gap. Due to the fact that the size of the waveguides is much smaller than the wavelength of light that propagates in the structure, a significant fraction of the optical mode is in the air gap between the waveguides. By changing the size of the air gap using MEMS techniques, we can vary this fraction and hence the effective refractive index of the waveguide structure, thus generating tunable optical delay. The optical buffer structure was grown on an InP substrate by molecular beam epitaxy, and the device layer was made of InGaP. An InGaAs layer was sandwiched between the device layer and the substrate to serve as a sacrificial layer. The sub-micron waveguides, their supports in the form of side pillars with tapered shapes in order to minimize optical losses, and the MEMS structures were patterned using electron beam lithography and plasma etching. Electrodes were integrated into the structure to provide electrostatic actuation. After the sample patterning, the waveguide structure was released using HF etch. Our simulations predict that by varying the waveguide separation from 50 nm to 500 nm, we could achieve a change in propagation delay by a factor of two.

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

    Seffah, Ahmed


    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

  16. 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

    柴增铧; 齐钺


    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。

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

    罗嗣碧; 唐方清; 孔祥升; 杨华振


    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.

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



    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.

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

    Solazzi L.


    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.


    N. N. Melnichuk


    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.

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

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

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


    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.

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

    杨文; 何耀炜


    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.

  4. 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

    王福敏; 罗强; 李军


    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

  5. Development of a bridge transported servo manipulator for the maintenance of the hot cell equipment - a prototype design

    Mechanical Master - Slave Manipulators (MSMs ) which are mounted on the hot cell wall cannot access all the areas for the equipment maintenance due to their reach limitation. A Bridge Transported Servo Manipulator (BTSM) has been designed to overcome the limitation of access that is a drawback of the MSMs for the equipment maintenance. The BTSM system consists of four components : a transporter with a telescoping tubeset , a slave manipulator, a master manipulator, and a remote control system. T he BTSM system has been designed by Solid Edge which is a 3D CAD, except for the remote control system. In this paper, it is addressed the design and analysis of the mechanical parts, except for the design of the remote control system

  6. Bridge? What's a Bridge?

    Gutsche, George


    Considers the metaphor of the "bridge" as it applies to Russian-language courses at the university level. The article examines broader curricular issues of technology, innovation, and outside pressures on language teaching. (22 references) (CK)

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

    Gerlach, Torsten; Durak, Umut


    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...

  8. Design and implementation of a monitoring system applied to a long-span prestressed concrete bridge

    H. Sousa; Figueiras, J; Félix, C; Bento, J.


    Currently, long-term monitoring systems are mandatory for major civil engineering structures such as bridges, tunnels and dams. Generally, they monitor a set of physical, chemical and mechanical parameters in critical sections of the structure by incorporating appropriate sensors. The set of data collected demonstrates great potential in the prevention of damage and contributes to more efficient maintenance of the structures monitored. This work presents the long-term monitoring system instal...

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


    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.

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

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


    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. Railroad Bridges

    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...

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

    Nentawe Y. Goshwe


    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.

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


    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.%  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。

  14. Integral Abutment and Jointless Bridges

    Cristian-Claudiu Comisu


    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...

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

    乔建东; 吴慧山; 杨伟


    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%.

  16. Control and design of full-bridge three-level converter for renewable energy sources

    Yao, Zhilei; Xu, Jing; Guerrero, Josep M.


    Output voltage of renewable energy sources, such as fuel cell and PV cell, is often low and varies widely with load and environmental conditions. Therefore, the high step-up DC-DC converter is needed between renewable energy sources and the grid-connected inverter. However, voltage stress of...... rectifier diodes is high and filter is large in traditional voltage-source converters in a wide input-voltage range. In order to solve the aforementioned problems, a full-bridge (FB) three-level (TL) converter is proposed. It can operate at both two-level and three-level modes, so it is suitable for wide...

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



    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

  18. 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

    张效奎; 刘伟; 韩国梁; 李娟娟


    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.

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

    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

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

    Makda, Ishtiyaq Ahmed; Nymand, Morten


    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......-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....... 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...

  1. 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

    张慕圣; 陈锐斌


    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.

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

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


    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

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

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


    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.

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

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


    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.

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

    Hauge, Trond Eiliv


    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…

  6. Bridging the gaps in design methodologies by evolutionary optimization of the stability and proficiency of designed Kemp eliminase KE59

    Khersonsky, Olga; Kiss, Gert; Röthlisberger, Daniela; Dym, Orly; Albeck, Shira; Houk, Kendall N.; Baker, David; Tawfik, Dan S.


    Computational design is a test of our understanding of enzyme catalysis and a means of engineering novel, tailor-made enzymes. While the de novo computational design of catalytically efficient enzymes remains a challenge, designed enzymes may comprise unique starting points for further optimization by directed evolution. Directed evolution of two computationally designed Kemp eliminases, KE07 and KE70, led to low to moderately efficient enzymes (kcat/Km values of ≤ 5 × 104 M-1s-1). Here we de...

  7. Environment-behaviour studies: A synergetic bridge between designers and users of open space

    Barbara Goličnik


    Full Text Available This paper critically reflects on a kind and use of knowledge about the users of urban open public spaces in urban planning and design. It shows that designers’ perceptions about usage-spatial relationships are inadequate and many times very different form the actual situations. The findings are based on results from workshops with urban landscape designers and on the basis of observation and behavioural mapping in squares and parks of city centres of two European cities, Edinburgh and Ljubljana. As the behavioural maps graphically express structural relationships between physical qualities of places and their users, they represent a useful tool for improvement of designers’ knowledge and perception about potential and actual use of a place. In this respect they represent a basis for better cooperation and synergy between users and planners or designers, as the knowledge about any possible or expected behavioural patterns in places may lead into effective and responsive design.

  8. Design of the overhead bridge crane beam and strenght analysis for given loads

    Armán Morales, Sergio


    The main aim of the project is: for given loads, analyse and design (analytically and with Catia software) different beams for an overhead crane. For this purpose, it will be study the theory of cranes and structures calculation and from this theory I will design an algorithm that allows finding the necessary beam from de European standard metallic beam list. After obtaining the analytical and the software (Catia) results for each beam, it will be compare the results between them and presente...

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

    Mona Komeijani


    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%.

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

    Guenther, Milan


    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

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

    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


    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...

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

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


    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

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

    Wilson, Joe M.


    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…

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



    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.

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

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


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

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


    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...

  17. Designing a Time-Aware Service System: Bridging the Front and Back Stages in Service System Design

    Rhee, Seung-Hyun


    A service "system" implies a systematic strategy, design, implementation, operation, and evaluation of services. This systematic approach enables to more specifically define intrinsic problems of services and solve them. One of the problems involves time efficiency; it affects the quality of each service and, as a result, customer satisfaction. In other words, time efficiency has been one of the most critical factors in services' competitive power. Therefore, this paper recognizes the importa...

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


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

    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


    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.

  20. Myocardial Bridging.

    Yuan, Shi-Min


    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. PMID:27074276

  1. Myocardial Bridging

    Shi-Min Yuan


    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.

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



    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.

  3. The Building Bridges Project: Involving Older Adults in the Design of a Communication Technology to Support Peer-to-Peer Social Engagement

    Wherton, Joseph; Prendergast, David

    There are a variety of factors that can lead to social isolation and loneliness in old age, including decline in physical and mental health, as well as change to social environment. The Building Bridges project explores how communication technology can help older adults remain socially connected. This paper will first provide an overview of a prototype communication system designed to support peer-to-peer group interaction. A description of the user-centered design process will be provided to demonstrate the importance of involving older adults at the earliest stages. The implications for designing new technology for older adults are discussed.

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

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


    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...

  5. Wave-current force on bridge foundation

    Pan, J.N.; Wang, D.T.; Wang, X. G.; Nie, F


    Many cross-sea bridges have been constructed or in construction in the Chinese coastal areas, such as Hangzhou Bay Bridge, East China Sea Bridge and Hong Kong-Zhuhai-Macau Bridge, etc. Usually the foundations of cross-sea bridges will bear the load of wave and current simultaneously, the extreme value of which is an important factor for bridge design. It is quite difficult to estimate the extreme wave-current forces on bridge foundations due to their complex form, for example a polygonal plat...

  6. Bridging a cultural gap

    Leviatan, Talma


    There has been a broad wave of change in tertiary calculus courses in the past decade. However, the much-needed change in tertiary pre-calculus programmes—aimed at bridging the gap between high-school mathematics and tertiary mathematics—is happening at a far slower pace. Following a discussion on the nature of the gap and the objectives of a potential bridging programme, this paper aims at demonstrating that the gap can be bridged, by presenting an ongoing modular bridging programme especially designed for the diverse types of student populations in teachers training colleges. We also present here some innovative teaching and assessment methods that were judged essential for the success of these programmes—focusing mainly on the "Questionnaire Based Instruction Method". Finally we suggest directions of follow up and research.

  7. 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



    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.

  8. 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

    孙英杰; 梅新咏


    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

  9. 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



    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.

  10. Estimation procedure of nonlinear maximum displacement response of steel bridge pier in seismic design; Kosei kyokyaku no dansosei saidai oto hen`i suiteiho ni tsuite

    Nakajima, A. [Utsunomiya University, Tochigi (Japan); Miyama, D. [Metropolitan Expressway Public Corp., Tokyo (Japan); Otsuka, H. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Sato, T. [Ministry of Construction, Tokyo (Japan); Suzuki, M. [Tohoku University, Sendai (Japan)


    In this paper, in order to investigate an accuracy of the equal energy assumption which is often adopted in evaluating their nonlinear maximum displacement response in seismic design, parametric studies on elasto-plastic behavior of steel bridge pier are carried out. First, the comparison between the maximum displacement response of the steel bridge pier evaluated by the equal energy assumption and the one obtained by the elasto-plastic dynamic response analysis shows that there is a quite difference between them. Secondly, an estimation procedure of the maximum displacement response of the steel pier employing an equivalent SDOF system with bilinear restoring characteristics is proposed and its efficiency is confirmed. 15 refs., 13 figs., 1 tab.

  11. 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

    王鸽; 肖稀; 曾建伟; 吴智宇


    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.

  12. Bridge Management Systems

    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....

  13. 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



    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。

  14. Programmevaluierung Bridge

    Warta, Katharina; Good, Barbara; Geyer, Anton


    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 ...

  15. 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



    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.

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

    郭安辉; 张门哲


    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

  17. National Bridge Inventory (NBI) Bridges

    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,...

  18. Nondestructive testing for bridge diagnosis

    There are many motivations for bridge diagnosis using Nondestructive testing (NDT) to monitor its integrity. The measured frequency and damping on real bridge are compared in one figure as a function of span length and general aspects are explained. These date were measured in every construction of bridges and applied to design new bridges. Ultrasonic testing is also well used for concrete and steel members mainly to detect internal damages or delaminations. Detail analysis on reflected waves gives us more accurate information about the defect. Experimental results are shown as examples in this paper.

  19. Modelling railway bridge asset management

    Le, Bryant Linh Hai


    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...

  20. Vulnerability of bridges to fire

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


    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...

  1. Thermal bridges of modern windows

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


    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 wi...

  2. Vulnerability of bridges to fire

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


    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 endan...

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

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


    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

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

    Du, Guangli; Karoumi, Raid


    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 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...... scenarios outlined. LCA study is performed with the ReCiPe methodology with life cycle inventories data from public database. Five selected mid-point level impact categories and the energy consumption are presented. The result shows that the steel bridge has a better environmental performance due to the...

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

    Park, Kiwoo; Chen, Zhe


    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...... ripples without increasing switching losses or device stresses. Analysis of both the input and output current characteristics and design aspects of the transformer, the filter inductor, and the input and output filter capacitors will be presented. Considering the high maintenance cost and fault tolerant...... requirements, this modular converter concept is expected to be highly beneficial especially for the offshore wind farm application....

  6. Building Bridges

    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...

  7. Bridge engineering handbook construction and maintenance

    Chen, Wai-Fah


    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

  8. Istanbul Bridge Conference 2014

    Gülkan, Polat; Mahmoud, Khaled


      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.

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

    胡明义; 黄冰释; 余俊林; 唐守峰


    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

  10. 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

    郭会歌; 薛鹏; 杨军宁; 王永利


    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.

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

    杨磊; 吴晓光; 羊彦


    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.

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

    Vinayaka B.C


    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.

  13. New Concept for Durable Concrete Bridges

    Damek, Marek


    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 ...

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

    Shunquan Qin; Pu Zhou; Youheng Hua


    @@ 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.

  15. Stone bridges

    Drdácký, Miloš; Slížková, Zuzana

    Prague : Institute of theoretical and applied mechanics AS CR, v.v.i, 2011 - (Drdácký, M.; Binda, L.; Hennen, I.; Kőpp, C.; Lanza, L.), s. 122-129 ISBN 978-80-86246-37-6 Grant ostatní: evropská komise(XE) CHEF-SSPI-044251 Institutional research plan: CEZ:AV0Z20710524 Keywords : flood * stone bridge * cultural heritage Subject RIV: AL - Art, Architecture, Cultural Heritage

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

    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


    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

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

    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


    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

  18. 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



    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.

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

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


    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.

  20. 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

    王东升; 孙治国; 郭迅; 李晓莉; 霍燚


    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.

  1. 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



    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.

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

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


    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

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

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


    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.

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

    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

  5. Applications of overburden conveyor bridges

    Schachtschneider, H.


    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.

  6. Probabilistic Performance-Based Optimum Seismic Design of Seismic Isolation for California High-Speed Rail Prototype Bridge

    Li, Yong


    Over the last five decades, remarkable progress has been achieved in the field of earthquake engineering, especially in the following areas: seismic design philosophy, earthquake protective systems, seismic design and performance evaluation of structures, and theory of structural optimization. The progress achieved and products developed in these areas can be integrated to develop a desired computer-aided optimum structural design framework. Accordingly, a probabilistic performance-based opti...

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

    杨庸; 雷俊卿


    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

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

    雷正保; 宁寒


    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

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



    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

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



    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

  11. 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

    王镇道; 赵亚魁; 章兢; 吴旭; 易峰


    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。

  12. [Retention of adhesive bridges].

    Raes, F; De Boever, J


    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

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

    Mohamad Kassema


    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. 

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

    Roehl, Amy


    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.…

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

    Ahmad, Javaid; Cheng, Shaohong; Ghrib, Faouzi


    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.

  16. Cognitive task load and support on a ship's bridge : Design and evaluation of a prototype user interface

    Grootjen, M.; Neerincx, M.A.; Passenier, P.O.


    Recently, four cognitive support concepts were developed, that should help to handle high-y demand situations. These concepts are based on a cognitive task load model and can be realised with a specific method for cognitive task load analysis. The model and method describe task load in terms of three behavioural factors: the percentage time occupied, the level of information processing and the number of task-set switches. This paper shows the design and evaluation of a prototype user interfac...

  17. Bridging the gap between human and machine trust : applying methods of user-centred design and usability to computer security

    Karvonen, Kristiina


    This work presents methods for improving the usability of security. The work focuses on trust as part of computer security. Methods of usability and user-centred design present an essential starting point for the research. The work uses the methods these fields provide to investigate differences between machine and human trust, as well as how the technical expressions of trust could be made more usable by applying these methods. The thesis is based on nine publications, which present various ...

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

    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

  19. A user-friendly design of the webs of steel bridges subjected to many times repeated loading

    Škaloud, Miroslav; Zörnerová, Marie

    Chichester : Horwood publishing, Chichester, UK, 2008 - (Jármai, K.; Farkas, J.), s. 343-352 ISBN 978-1-904275-28-2. [Design, fabrication and economy of welded structures. Miskolc (HU), 24.04.2008-26.04.2008] R&D Projects: GA ČR(CZ) GA103/06/0064; GA AV ČR(CZ) IAA200710603; GA ČR(CZ) GA103/05/2003; GA ČR(CZ) GA103/05/2066 Institutional research plan: CEZ:AV0Z20710524 Keywords : plated structures * post-buckled behaviour * repeated loading Subject RIV: JM - Building Engineering

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

    钟运平; 程小华; 张勇; 程声烽


    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。

  1. Bridging worlds

    Rose, Jeremy; Memon, Saifullah Hassan


    (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...

  2. Seismic Passive Control of Cable-Stayed Bridges

    Ali, Hosam-Eddin M.; Abdel-Ghaffar, Ahmed M.


    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...

  3. 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

    罗扣; 王东晖; 张强


    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.

  4. 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

    章治国; 余海生


    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.

  5. Design of six pulse bridge multiplication converter model for current harmonic elimination of three phase ac-dc converter

    The recent development of semiconductor technology and wide spread use of power electronic devices in power system have open the era of the power system harmonics due to increasing penetration of non-linear loads. Harmonics are widely admitted as most important issues of power quality which must be eliminated to maintain power system reliability. The tolerable THD (Total Harmonic Distortion) values must be bounded in well-defined limits recognized by IEEE-519 standard. In this work, in order to eliminate the current harmonics produced by non-linear loads, six pulse multiplication converter technique in conjunction with STSSHPE (Single Tuned Shunt Harmonic Passive Filter) is proposed. The proposed model has the capacity of harmonic cancellation of the dominant 3rd order harmonics. Besides that, the 5th and 7th order harmonics are also reduced to a diminishing level. The hardware model has been experimentally tested by PQA (Power Quality Analyzer) and simulation model is designed using MATLAB software. The acquired results have been measured by considering THD values in terms of current and voltage. Furthermore, they have been compared against IEEE-519 performance standards. The prosed model, successfully bounds the total harmonic distortion under defined limits by IEEE-519 standard. (author)

  6. Myocardial bridges: morphological and functional aspects.

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


    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...

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

    van Manen, S. M.


    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

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

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


    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......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 transformer; this structure minimizes the number of the switching transistors and their associate gate driver components. With phase-shift control strategy, all the switches are operated under zero-voltage switching (ZVS) condition. Furthermore, in order to optimize the converter performance and increase...

  9. 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

    檀永刚; 陈亮; 张哲


    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

  10. Architectural engineering of FRP bridges

    Smits, J.E.P.


    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.

  11. Bridge Aesthetics and Structural Honesty

    Gimsing, Niels Jørgen


    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 ...

  12. 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

    张云; 谭平; 郑建勋; 周福霖


    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 .

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

    李永; 张承瑞; 翟鹏; 胡天亮; 林明星


    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.

  14. Bridge Coupler for APT

    Greninger, P T; Spalek, G; Greninger, Paul T.; Rodarte, Henry J.


    The Coupled Cavity Drift Tube Linac (CCDTL) used in the Accelerator for the Production of Tritium (APT) is fully described elsewhere [1]. The modules are composed of several machined and brazed segments that must account for the accumulation of dimensional tolerances in the build up of the stack. In addition, space requirements dictate that power fed to the accelerator cannot be through the accelerating cavities. As well, we would like to remove a single segment of the accelerator without removing additional segments. These requirements combined with phasing relationships of the design and space limitations have resulted in a different bridge coupling method used in the module comprising 3-gap segments. The coupling method, phasing relationships and other features that enhance the flexibility of the design will be discussed.

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



    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.

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



    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.

  17. Halliburton Composite Bridge Plug Assembly

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


    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.

  18. The evaluation of bicycle paths on bridges

    Wang, Hwa-chyi; De Backer, Hans; Lauwers, Dirk; Chang, SK Jason


    Bicycle accidents have increasingly caused casualties and property damage. Many countries have therefore started to pay more attention to designing the space of bicycle paths. However, few studies have focused on the design of bicycle continuity between each bicycle path. In this study, the concept of using both spatial crash probability (P) and crash severity index (CSI) is introduced to address the bicycle safety issue on bridges in Central Business Districts (CBDs). Bicycle paths on bridge...

  19. Half Bridge Inductive Heater



    Full Text Available Induction heating performs contactless, efficient and fast heating of conductive materials, therefore became one of the preferred heating procedure in industrial, domestic and medical applications. During induction heating the high-frequency alternating currents that heat the material are induced by means of electromagnetic induction. The material to be heated is placed inside the time-varying magnetic field generated by applying a highfrequency alternating current to an induction coil. The alternating electromagnetic field induces eddy currents in the workpiece, resulting resistive losses, which then heat the material. This paper describes the design of a power electronic converter circuit for induction heating equipment and presents the obtained results. The realized circuit is a low power half bridge resonant inverter which uses power MOS transistors and adequate driver circuits.

  20. [A newly designed salt bridge cap-type, a variable, and non-invasive EEG lead electrode and the analytical power spectrum].

    Ohsawa, K; Mikawa, J


    A newly devised, variable EEG cap-style electrode that has an electrical salt bridge with 2% agarose gel and 5% NaCl solution was developed. The number of electrodes can be increased as required. The weight of 15 electrodes is about 100g. The electrode is simple, fast and in a one-touch form for measuring the EEG. An EEG using this electrode system was recorded in a healthy man in a sitting position on a chair, at rest, and with eyes closed. The power spectrum showed different patterns for the power at different concentrations of aqueous solution in the matrix of the salt bridge. The power changed to a pattern of J-type with 20% NaCl solution, to a pattern of U-type with 5% NaCl solution, and to a pattern of L-type with 0.9% NaCl solution, respectively. The matrix of the salt bridge that has a concentration higher than 0.9% NaCl, is a hypertonic solution for the isotonic body liquid. One person felt pain in half of the part of the experiment when a 20% NaCl hypertonic solution was applied to the scalp, so a 20% NaCl solution of the salt bridge was used in experiments concerning osmosis. When a salt bridge of 5% NaCl solution was used, the same results of the wave measurement was obtained 10 times. It was a value close to the expected measurement so it has a high probability of being correct. At this time the power spectrum shows a U-type pattern consistently. PMID:1591099

  1. Violin Bridge Mobility Analysis under In-Plane Excitation

    Cheng-Zhong Zhang


    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.

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

    Laurendeau, Matthew P.


    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...

  3. 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

    罗家安; 黄亚栋; 张鹏飞; 张跃博


    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。

  4. 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



    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.

  5. Generalized Gaussian Bridges

    Sottinen, Tommi


    A generalized bridge is the law of a stochastic process that is conditioned on linear functionals of its path. We consider two types of representations of such bridges: orthogonal and canonical. In the canonical representation the filtrations and the linear spaces generated by the bridge process and the original process coincide. In the orthogonal representation the bridge is constructed from the entire path of the underlying process. The orthogonal representation is given for any continuous Gaussian process but the canonical representation is given only for so-called prediction-invertible Gaussian processes. Finally, we apply the canonical bridge representation to insider trading by interpreting the bridge from an initial enlargement of filtration point of view.

  6. Partially entangled states bridge in quantum teleportation

    Cai, Xiao-Fei; Yu, Xu-Tao; Shi, Li-Hui; Zhang, Zai-Chen


    The traditional method for information transfer in a quantum communication system using partially entangled state resource is quantum distillation or direct teleportation. In order to reduce the waiting time cost in hop-by-hop transmission and execute independently in each node, we propose a quantum bridging method with partially entangled states to teleport quantum states from source node to destination node. We also prove that the designed specific quantum bridging circuit is feasible for partially entangled states teleportation across multiple intermediate nodes. Compared to two traditional ways, our partially entanglement quantum bridging method uses simpler logic gates, has better security, and can be used in less quantum resource situation.

  7. Active Control of Long Bridges Using Flaps

    Hansen, H. I.; Thoft-Christensen, Palle

    The main problem in designing ultra-long span suspension bridges is flutter. A solution to this problem might be to introduce an active flap control system to increase the flutter wind velocity. The investigated flap control system consists of flaps integrated in the bridge girder so each flap is...... different flap configurations for a bridge section model by using aerodynamic derivatives for a flat plate. The example shows that different flap configurations can either increase or decrease the flutter wind velocity. for optimal flap configurations flutter will not occur....

  8. 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

    方海; 韩娟; 刘伟庆; 祝露


    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。

  9. Inspection Strategies for Concrete Bridges

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    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....

  10. Concrete bridge prioritization system

    Kesselring, Debbie Anne


    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...


    Shrikant D. Bobade *, Dr. Valsson Varghese


    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...

  12. Bridging the Gap

    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....

  13. Bridging the Gap

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


    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...

  14. Project of industrial hall with a bridge crane

    Ambrožič, Klemen


    In graduation thesis design of steel industrial hall with a bridge crane is performed. The first chapter contains technical report of the structure. Followed by the second chapter, which analyzes bridge crane and crane track. The influences of bridge crane are determined. These influences are considered for design of the crane track, fatigue check and displacements of the crane supporting structure. Fatigue check contains basic detail. The third chapter contains analysis of the hall supportin...

  15. Post-earthquake Traffic Capacity of Modern Bridges in California

    Terzic, Vesna


    Evaluation of the post-earthquake capacity of a bridge to carry self-weight and traffic loads is essential for a safe and timely re-opening of the bridge after an earthquake. Although modern highway bridges in California designed using the Caltrans Seismic Design Criteria are expected to maintain at minimum a gravity load-carrying capacity during both frequent and extreme seismic events, as of now, there are no validated, quantitative guidelines for estimating the remaining load carrying capa...

  16. 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


    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.

  17. 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

    史永胜; 李晓明; 高丹阳


    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。

  18. 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

    叶湖; 周唯逸; 贾文超; 姜明伟


    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。

  19. 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

    周孝军; 牟廷敏; 丁庆军; 聂传振


    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。

  20. Principles of Bridge Reliability

    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...

  1. The floating water bridge

    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

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

    Haijun Wang; Jiandong Wang; Hua Wei


    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...

  3. 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

    徐关尧; 田静; 李和; 朱杰


    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。

  4. Design and Evaluation of New Tc-99m-Labeled Lactam Bridge-Cyclized Alpha-MSH Peptides for Melanoma Imaging

    Guo, Haixun; Gallazzi, Fabio; Miao, Yubin


    The purpose of this study was to examine the melanoma targeting and imaging properties of new 99mTc-labeled lactam bridge-cyclized alpha-melanocyte stimulating hormone (α-MSH) peptides using bifunctional chelating agents. MAG3-GGNle-CycMSHhex, AcCG3-GGNle-CycMSHhex and HYNIC-GGNle-CycMSHhex peptides were synthesized and their melanocortin-1 (MC1) receptor binding affinities were determined in B16/F1 melanoma cells. The biodistribution of 99mTc-MAG3-GGNle-CycMSHhex, 99mTc-AcCG3-GGNle-CycMSHhex...

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

    Lei Su-su


    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.

  6. 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



    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.

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



    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...

  8. 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

    吴立斌; 郭冉冉; 李国刚


    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。

  9. Solving Topological and Geometrical Constraints in Bridge Feature Model

    PENG Weibing; SONG Liangliang; PAN Guoshuai


    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.

  10. Active aerodynamic stabilisation of long suspension bridges

    Nissen, Henrik Ditlev; Sørensen, Paul Haase; Jannerup, Ole Erik


    use of control analysis and design techniques, a linear model of the structural and aerodynamic motion around equilibriun is developed. The model is validated through comparison with finite element calculations and wind tunnel experimental data on the Great Belt East Bridge in Denmark. The developed......The paper describes the addition of actively controlled appendages (flaps) attached along the length of the bridge deck to dampen wind-induced oscillations in long suppension bridges. A novel approach using control systems methods for the analysis of dynamic stability is presented. In order to make...... active control scheme is local in that the flap control signal at a given longitudinal position along the bridge only depends on local motion measurements. The analysis makes use of the Nyquist stability criteria and an anlysis of the sensitivity function for stability analysis. The analysis shows that...