WorldWideScience

Sample records for bridge design

  1. Virtual Bridge Design Challenge

    Science.gov (United States)

    Mitts, Charles R.

    2013-01-01

    This design/problem-solving activity challenges students to design a replacement bridge for one that has been designated as either structurally deficient or functionally obsolete. The Aycock MS Technology/STEM Magnet Program Virtual Bridge Design Challenge is an authentic introduction to the engineering design process. It is a socially relevant…

  2. Students design composite bridges

    NARCIS (Netherlands)

    Stark, J.W.B.; Galjaard, J.C.; Brekelmans, J.W.P.M.

    1999-01-01

    The paper gives an overview of recent research on steel-concrete composite bridge design by students of Delft University of Technology doing their master's thesis. Primary objective of this research was to find possibilities for application of steel-concrete composite bridges in the Netherlands,

  3. Preliminary bridge design navigation tool for novices

    OpenAIRE

    Boulanger, Sylvie

    1997-01-01

    The motivation of the thesis comes from the frustrations of young engineers confronted with real design problems. The inspiration of the thesis evolved from observations of bridge designers and analyses of bridge design competitions. Not only do designers adopt more than one strategy during design, they rarely perform a fixed sequence of tasks. Not only do designers consider more than one criterion during design, their priorities shift during the determination of parameters. The choice of tas...

  4. Preliminary bridge design navigation tool for novices

    OpenAIRE

    Boulanger, Sylvie; Hirt, Manfred A.

    2008-01-01

    The motivation of the thesis comes from the frustrations of young engineers confronted with real design problems. The inspiration of the thesis evolved from observations of bridge designers and analyses of bridge design competitions. Not only do designers adopt more than one strategy during design, they rarely perform a fixed sequence of tasks. Not only do designers consider more than one criterion during design, their priorities shift during the determination of parameters. The choice of tas...

  5. Multimedia package for LRFD concrete bridge design.

    Science.gov (United States)

    2009-02-01

    This Project developed a Load and Resistance Factor Design (LRFD) multimedia package to provide a practical introduction and an in-depth understanding of the technological advances in the design of concrete bridges. This package can be used to train ...

  6. Salt bridges: geometrically specific, designable interactions.

    Science.gov (United States)

    Donald, Jason E; Kulp, Daniel W; DeGrado, William F

    2011-03-01

    Salt bridges occur frequently in proteins, providing conformational specificity and contributing to molecular recognition and catalysis. We present a comprehensive analysis of these interactions in protein structures by surveying a large database of protein structures. Salt bridges between Asp or Glu and His, Arg, or Lys display extremely well-defined geometric preferences. Several previously observed preferences are confirmed, and others that were previously unrecognized are discovered. Salt bridges are explored for their preferences for different separations in sequence and in space, geometric preferences within proteins and at protein-protein interfaces, co-operativity in networked salt bridges, inclusion within metal-binding sites, preference for acidic electrons, apparent conformational side chain entropy reduction on formation, and degree of burial. Salt bridges occur far more frequently between residues at close than distant sequence separations, but, at close distances, there remain strong preferences for salt bridges at specific separations. Specific types of complex salt bridges, involving three or more members, are also discovered. As we observe a strong relationship between the propensity to form a salt bridge and the placement of salt-bridging residues in protein sequences, we discuss the role that salt bridges might play in kinetically influencing protein folding and thermodynamically stabilizing the native conformation. We also develop a quantitative method to select appropriate crystal structure resolution and B-factor cutoffs. Detailed knowledge of these geometric and sequence dependences should aid de novo design and prediction algorithms. Copyright © 2010 Wiley-Liss, Inc.

  7. Design aids of NU I-girders bridges.

    Science.gov (United States)

    2010-05-01

    Precast prestressed concrete I-Girder bridges have become the most dominant bridge system in the United States. In the early design : stages, preliminary design becomes a vital first step in designing an economical bridge. Within the state of Nebrask...

  8. Update of bridge design standards in Alabama for AASHTO LRFD seismic design requirements.

    Science.gov (United States)

    2013-11-01

    The Alabama Department of Transportation (ALDOT) has been required to update their bridge design to the LRFD Bridge Design Specifications. This transition has resulted in changes to the seismic design standards of bridges in the state. Multiple bridg...

  9. Implementation of sustainability in bridge design, construction and maintenance.

    Science.gov (United States)

    2012-12-01

    The focus of this research is to develop a framework for more sustainable design and construction : processes for new bridges, and sustainable maintenance practices for existing bridges. The framework : includes a green rating system for bridges. The...

  10. Guardrails for Use on Historic Bridges: Volume 2—Bridge Deck Overhang Design

    OpenAIRE

    Frosch, Robert J.; Morel, Adam J.

    2016-01-01

    Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

  11. New conceptual design of portable bamboo bridge for emergency purposes

    Science.gov (United States)

    Musthaffa, A. A.; Nor, N. M.; Yusof, M. A.; Yuhazri, M. Y.

    2018-02-01

    Portable bridges serve as routes for troops during the military operations and the disaster relief operation. Nowadays, bamboo has been regarded as one of the alternative construction materials for building and bridge structures. This paper presents the conceptual design of the portable bridge. Several types of portable bridges and bamboo bridges are reviewed in the current work. The characteristics, capability and method of construction of each bridge are discussed. Finally, the conceptual of the portable bamboo bridge for emergency purposes is presented. The idea of producing portable bridge is proposed in the current work as it is crucial for providing route for communities affected by natural disasters.

  12. Design and Analysis of Collapsible Scissor Bridge

    Directory of Open Access Journals (Sweden)

    Biro Mohamad Nabil Aklif

    2018-01-01

    Full Text Available Collapsible scissor bridge is a portable bridge that can be deployed during emergency state to access remote areas that are affected by disaster such as flood. The objective of this research is to design a collapsible scissor bridge which is able to be transported by a 4x4 vehicle and to be deployed to connect remote areas. The design is done by using Solidworks and numerical analysis for structural strength is conducted via ANSYS. The research starts with parameters setting and modelling. Finite element analysis is conducted to analyze the strength by determining the safety factor of the bridge. Kutzbach equation is also analyzed to ensure that the mechanism is able to meet the targeted degree of motion. There are five major components of the scissor structure; pin, deck, cross shaft and deck shaft. The structure is controlled by hydraulic pump driven by a motor for the motions. Material used in simulation is A36 structural steel due to limited library in ANSYS. However, the proposed material is Fiber Reinforced Polymer (FRP composites as they have a high strength to weight ratio. FRP also tends to be corrosion resistance and this characteristic is useful in flooded area.

  13. A bridge with a view, a view with a bridge : Identifying design considerations for bridges to strengthen regional identity

    NARCIS (Netherlands)

    Smits, J.E.P.; van der Hoeven, F.D.

    2015-01-01

    This paper discusses design considerations for creating high quality infrastructural artefacts with an emphasis on bridges. The authors pursue a design study and analysis approach to highlight the specifics of infrastructure design for regional identity, based on their own work on a bridge

  14. Design of bridges against large tectonic deformation

    Science.gov (United States)

    Anastasopoulos, I.; Gazetas, G.; Drosos, V.; Georgarakos, T.; Kourkoulis, R.

    2008-12-01

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

  15. Verification of LRFD Bridge Design and Analysis Software for INDOT

    OpenAIRE

    Varma, Amit H.; Seo, Jungil

    2009-01-01

    NCHRP Process 12-50 was implemented to evaluate and verify composite steel I-girder bridge design software used commonly in Indiana. A test-bed of twenty one bridges was developed with the guidance from an Indiana Department of Transportation appointed research advisory panel (RAP). The test-bed included five simple-span and sixteen multi-span bridge superstructures. More than 80 parameters were required to define a bridge and they include bridge span, girder spacing, number of beams, section...

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

    CERN Document Server

    Bakht, Baidar

    2015-01-01

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

  17. Determination of barge impact probabilities for bridge design.

    Science.gov (United States)

    2016-04-01

    Waterway bridges in the United States are designed to resist vessel collision loads according to design provisions released by the American Association of State : Highway and Transportation Officials (AASHTO). These provisions provide detailed proced...

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

    International Nuclear Information System (INIS)

    Hassan, M.I.U.

    2009-01-01

    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

  19. Improved bridge joint materials and design details.

    Science.gov (United States)

    2017-06-01

    Expansion joints accommodate bridge movements that result from factors such as thermal expansion and contraction, concrete shrinkage, creep effects, live loading, settlement of the foundation and substructure, and environmental stressors. Expansion j...

  20. Determination of barge impact probabilities for bridge design : [summary].

    Science.gov (United States)

    2016-04-01

    University of Florida researchers developed a revised barge impact probability expression applicable for the design of bridge structures located on Florida waterways. University of Florida researchers obtained barge flotilla traffic data and barge-to...

  1. Environmental comparison of a railway bridge with alternative designs

    DEFF Research Database (Denmark)

    Du, Guangli; Karoumi, Raid

    2012-01-01

    Railway bridges are complex structures that remain for a long life span and consume large amount of material and energy throughout the life span. All of those lead to considerable resource depletion and environmental burdens. Life Cycle Assessment (LCA) has proved to be a comprehensive tool...... for quantifying and assessing the environmental impacts of the products through its whole life cycle. This paper presents a comparative case study between two alternative designs of Banafjäl Bridge: ballast track design and fixed slab track design. The methodology of LCA is utilized as a supporting tool...

  2. Implementation of sustainable and green design and construction practices for bridges.

    Science.gov (United States)

    2012-12-01

    The focus of this research is to develop a framework for more sustainable design and construction : processes for new bridges, and sustainable maintenance practices for existing bridges. The framework : includes a green rating system for bridges. The...

  3. Non-Flutter Design Principle for long Span Bridges

    DEFF Research Database (Denmark)

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

    velocity for a thin airfoil shows an asymptotical behavior. In traditional bridge design the torsional-to-vertical frequency ratio is increased to obtain higher flutter wind velocities. In the present study, we investigate, what we will label the non-flutter design principle, in which the torsional...

  4. Design of Usui bridge (PC cable stayed bridge). Usuihashi (PC shachokyo) no sekkei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Kido, M.; Iizuka, Y. (Japan Highway Public Corp., Tokyo (Japan)); Tanaka, S.; Otsuka, K. (P.S. Concrete Co. Ltd. Kajima Corp. Joint Venture, Tokyo (Japan)); Kitakuni, S. (Kajima Corp., Tokyo (Japan))

    1991-11-30

    Structure and design of single suspension PC cable bridge, which is first kind of high way bridge in Japan and aiming to start for general use by March, 1993, are reported. As a construction outline, main construction quantity and general layout of the whole bridge together with the selective detail and characteristics of the diagonal member, tower, main girder and tower support member, are cited. Design conditions( load, materials, allowable stress and others ), basic plan of the design, and structure analysis( surface stress framed structure analysis, stereoscopic framework analysis and FEM analysis of local stress ) are explained. Design of structure member like main girder is based on diagonal member tension, wave shearing force, level of diagonal strain stress, bending stress when diagonal member anchors the deformed main tower caused by living load during earth quake, principal stress of main tower junction and local stress etc. Main tower support member design is based on the results of corbel shearing force at varied cross section and main stress, and diagonal member design is decided by allowable stress. Diagonal member anchorage traverse beam design depends on bending moment of traverse beam and shearing force. 3 refs., 15 figs., 1 tab.

  5. Research on Multidisciplinary Optimization Design of Bridge Crane

    Directory of Open Access Journals (Sweden)

    Tong Yifei

    2013-01-01

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

  6. Design and Construction of Operation Bridge for Research Reactor

    International Nuclear Information System (INIS)

    Jung, Kwangsub; Choi, Jinbok; Lee, Jongmin; Oh, Jinho

    2015-01-01

    The operation bridge contains a lower working deck mounted on a saddle that travels on rails. Upright members are mounted on the saddle to support the upper structure and two hoist monorails. The saddle contains an anti-derail system that is composed of seismic lugs and guide rollers. The operation bridge travels along the rails to transport the fuel assembly, irradiated object, and reactor components in the pools by using tools. Hoists are installed at the top girder. The hoist is suspended from the monorail by means of a motor driven trolley that runs along the monorail. Movements of hoist and trolley are controlled by using the control pendant switch. Processes of design and construction of the operation bridge for the research reactor are introduced. The operation bridge is designed under consideration of functions of handling equipment in the pool and operational limits for safety. Structural analysis is carried out to evaluate the structural integrity in the seismic events. Tests and inspections are also performed during fabrication and installation to confirm the function and safety of the operation bridge

  7. Inclusive design: Bridging theory and practice

    NARCIS (Netherlands)

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

    2013-01-01

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

  8. Design Optimization of Hybrid FRP/RC Bridge

    Science.gov (United States)

    Papapetrou, Vasileios S.; Tamijani, Ali Y.; Brown, Jeff; Kim, Daewon

    2018-04-01

    The hybrid bridge consists of a Reinforced Concrete (RC) slab supported by U-shaped Fiber Reinforced Polymer (FRP) girders. Previous studies on similar hybrid bridges constructed in the United States and Europe seem to substantiate these hybrid designs for lightweight, high strength, and durable highway bridge construction. In the current study, computational and optimization analyses were carried out to investigate six composite material systems consisting of E-glass and carbon fibers. Optimization constraints are determined by stress, deflection and manufacturing requirements. Finite Element Analysis (FEA) and optimization software were utilized, and a framework was developed to run the complete analyses in an automated fashion. Prior to that, FEA validation of previous studies on similar U-shaped FRP girders that were constructed in Poland and Texas is presented. A finer optimization analysis is performed for the case of the Texas hybrid bridge. The optimization outcome of the hybrid FRP/RC bridge shows the appropriate composite material selection and cross-section geometry that satisfies all the applicable Limit States (LS) and, at the same time, results in the lightest design. Critical limit states show that shear stress criteria determine the optimum design for bridge spans less than 15.24 m and deflection criteria controls for longer spans. Increased side wall thickness can reduce maximum observed shear stresses, but leads to a high weight penalty. A taller cross-section and a thicker girder base can efficiently lower the observed deflections and normal stresses. Finally, substantial weight savings can be achieved by the optimization framework if base and side-wall thickness are treated as independent variables.

  9. Development of Secondary Route Bridge Design Plan Guides

    Science.gov (United States)

    2018-03-03

    The objective of this study is to develop a set of bridge plan guides for low-volume traffic roads. The purpose of the plans is to facilitate construction of new structures suitable for local agencies. The designs are to specifically address common l...

  10. Design and evaluation of steel bridges with double composite action

    Science.gov (United States)

    2010-02-01

    This report presents findings from a cooperative USF/URS/FDOT research study undertaken to develop design rules for : double composite steel bridges. In the study, a 48 ft long, 16 ft wide, 4 ft. 10 in. deep trapezoidal HPS 70W box section : desig...

  11. Bridges

    NARCIS (Netherlands)

    Zant, W.

    2017-01-01

    We estimate to what extent bridges in Mozambique lead to transport cost reductions and attribute these reductions to key determinants, in particular road distance, road quality and crossing borders. For identification we exploit the introduction of a road bridge over the Zambezi river, in August

  12. Design and construction of superstructure in prestressed concrete cable-stayed bridge. ; Aomori Bay Bridge. PC shachokyo jobuko no sekkei to seko. ; Aomori Bay Bridge

    Energy Technology Data Exchange (ETDEWEB)

    Ishibashi, T.; Fujimori, S.; Oba, M.; Tsuyoshi, T. (East Japan Railway Co., Tokyo (Japan))

    1991-12-01

    Aomori Bay Bridge is a 1,219m long elevated bridge, a part of No.2 Bay Highway of 1,993m in total length crossing over Aomori railway station which was planned in ordecr to integrate the port facilities of Aomori Harbor and expedite cargo traffic smoothly. Of this Bay Bridge, its main bridge portion crossing over Aomori railway station and the sea area was planned as a continuous prestressed concrete cable-stayed bridge of 498m in total length and consisting of three portions including the central portion in which the main span between the central bridge piers was 240m. It is scheduled to open in the summer of 1992. With regard to the design of this bridge, special care for the view of the bridge has been taken covering from the structure style to the accessories. For this bridge, a large scale underground continuous wall solid base with a box-shaped section consisting of 6 chambers was adopted for the base of a main tower. It has the cantilever suspension structure of the wide girder with the inverted Y-shaped pylons. For its stav cable, was adopted a large capacity stay cable with standard tensile strength of 1,942 fabricated on the site and for its covering tube, a FRP tube was adopted. In this article, the construction of the main girder and stay cables, and the construction control during their installation by projection are reported. 7 refs., 14 figs., 9 tabs.

  13. Christian Menn's recent bridge designs - Reducing structural elements to the simplest solution

    OpenAIRE

    Brühwiler, E.; Mahmoud, Khaled M.

    2009-01-01

    The conceptual designs by Christian Menn of four landmark bridges are presented: 1) a 350-m span cable-stayed bridge with jointless deck girder, 2) a cable-stayed bridge with a single “spindle-shaped” pylon, 3) a bridge with an arch reaching high above the deck (both carrying a horizontally curved deck girder), and 4) a cable stayed bridge with three pylons monolithically connected to the deck girder. All of the original bridge designs are driven by the aim to optimize the flow of force...

  14. A static analysis method for barge impact design of bridges with consideration of dynamic amplification : summary.

    Science.gov (United States)

    2009-11-01

    Several hundred Florida bridges span waterways deep enough for barge traffic. To ensure a bridge is capable of withstanding the potential impact of a barge collision, engineers use design specifications recommended by the American Association of Stat...

  15. Design and erection of the MUSEUM BRIDGE; Bijutsu no sekai eno yume no kakehashi. MUSEUM BRIDGE no sekkei seko

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, S.; Tsunekawa, M.; Umda, A.; Kishimoto, Y.; Yotsukura, Y.; Miitsu, K.; Okada, S.; Furukawa, M. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1998-12-20

    MUSEUM Projects for the religious corporation of Shinji-Shumeikai, at Shigaraki, Shiga prefecture. Fundamental design was by a project team led by the world-famous architect I.M. Pei. The museum is located in a prefectural park surrounded by forests. The design concept of the bridge aimed to connect Shangri-La (museum) to the real world. In order to satisfy this purpose, a cable-stayed bridge with external tendon was adopted as an original structure style, and details such as handrails, gratings, and gloss painting taken into consideration. The authors report the characteristics of the bridge and the sequence of erection. (author)

  16. An engineering design study of the transfer bridge for the SSC SDC detector

    International Nuclear Information System (INIS)

    Western, J.L.; Tulk, G.W.; Dittert, L.I.

    1993-05-01

    The transfer bridge is a major structural installation component for the large detector proposed by the Solenoidal Detector Collaboration (SDC). The transfer bridge is the structural device that allows for installation of the Muon Forward Toroid (MFT) and calorimeter components into the Muon Barrel Toroid (MBT). This paper summarizes the design and construction of the SDC transfer bridge

  17. Design and construction of the Natorigawa Bridge; Natorigawa kyoryo no sekkei/seko

    Energy Technology Data Exchange (ETDEWEB)

    Murai, Y.; Oba, M.; Omurata, Y. [JR East Japan Railway Co., Tokyo (Japan); Miyauchi, M.; Iwasaki, I. [Taisei Corp., Tokyo (Japan)

    1997-03-31

    The Natorigawa Bridge is reconstructed. Out of the reconstruction work, a report is made mainly on the design of the superstructure work of the PC panel-stayed bridge and the details of the work. In selecting bridge type, PC simple through beam bridge, steel trussed bridge, PC cable-stayed bridge, and PC panel-stayed bridge are compared, and a 2-span continuous PC panel-stayed bridge is adopted. Its appearance resembles that of the cable-stayed bridge, but the structure resembles a girder bridge. The appropriate span length is the intermediate range between those of the girder bridge and the cable-stayed bridge. Its trafficability is excellent with little deformation by the running of trains because the main beam, diagonal panel, and the main tower are connected rigidly to provide high rigidity of the entire bridge. PRC structure is employed in consideration of the restriction to beam height and economical efficiency. Analyses by a FEM model using two dimensional plane elements and by a few plane frame models as well as comparison of sectional force are performed for this bridge, and a proper plane model is selected. Substructure work, superstructure work and measurement work are described. 3 refs., 16 figs., 6 tabs.

  18. Bridging the gap between building science and design studios

    Energy Technology Data Exchange (ETDEWEB)

    Papamichael, Konstantinos; Pal, Vineeta

    2002-02-06

    Design studios and building science courses have been conducted independent of each other, mainly due to a lack of tools that allow quick and easy consideration of building science criteria, such as comfort and energy requirements, during the design process. Existing tools are not user-friendly and their use requires significant effort in gaining familiarity with the input requirements, understanding the modeling assumptions and interpreting the output. This paper is about the Building Design Advisor (BDA), an evolving computer-based tool intended to bridge the gap between design studios and building science considerations by addressing the above-mentioned limitations of existing tools. BDA allows automatic preparation of input files to multiple simulation tools while the user is working in a CAD environment. BDA automatically activates the relevant simulation tools when the user selects performance parameters to be computed and provides the results in a graphical form, allowing comparison of multiple design options with respect to multiple performance criteria. The paper includes considerations for the use of the BDA in the design studio and ends with a description of the current development efforts and future plans.

  19. Comparative analysis of design codes for timber bridges in Canada, the United States, and Europe

    Science.gov (United States)

    James Wacker; James (Scott) Groenier

    2010-01-01

    The United States recently completed its transition from the allowable stress design code to the load and resistance factor design (LRFD) reliability-based code for the design of most highway bridges. For an international perspective on the LRFD-based bridge codes, a comparative analysis is presented: a study addressed national codes of the United States, Canada, and...

  20. On Reliability Based Optimal Design of Concrete Bridges

    DEFF Research Database (Denmark)

    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...

  1. Continuous prestressed concrete girder bridges volume 1 : literature review and preliminary designs.

    Science.gov (United States)

    2012-06-01

    The Texas Department of Transportation (TxDOT) is currently designing typical highway bridge structures as simply supported using standard precast, pretensioned girders. TxDOT is interested in developing additional economical design alternatives for ...

  2. Recent design methods for prestressed concrete cable stayed bridge; PC shachokyo no sekkei gijutsu no genjo

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, K. [Kajima Corp., Tokyo (Japan)

    1995-02-01

    The number of constructed prestressed concrete cable stayed bridges reached nearly 100 in Japan, and the technique has greatly developed. In this article, the current status of design techniques for prestressed concrete cable stayed bridges were introduced along with the examples of constructed bridges for the analysis method and the design method for each structure part while introducing the current examples of constructed bridges. Also, this kind of extra-dosed prestressed concrete bridge and prestressed concrete bridge with prestressed concrete stays were reported. Standards have been prepared including a chapter for the prestressed concrete cable stayed bridges in the Road Bridge Guideline document in February 1990. Load to be noticed as the characteristics peculiar to the prestressed concrete cable stayed bridges includes the shock due to live load, temperature change, and execution error of a tower. For example, 1/1000 of the total tower height is generally considered as the execution error of the tower. A diagonal member is manufactured at factories and in fields and has both advantages and disadvantages. The linear analysis of plane framework is general. Damping of and earthquakeproof designs against the wind and earthquake of the diagonal member were also provided. 11 refs., 17 figs., 2 tabs.

  3. A static analysis method for barge-impact design of bridges with consideration of dynamic amplification : final report, November 2009.

    Science.gov (United States)

    2009-11-01

    Current practice with regard to designing bridge structures to resist impact loads associated with barge collisions relies upon the : use of the American Association of State Highway and Transportation Officials (AASHTO) bridge design specifications....

  4. The method of rapid design of the folding bridge based on floating supports

    Directory of Open Access Journals (Sweden)

    Jan Marszałek

    2016-09-01

    Full Text Available The article includes a methodology for the rapid design of the folding bridge based on floating supports. This methodology includes an analysis of the possibilities of using blocks from the park pontoon PP-64 as a support for the floating folding DMS-65 bridge, built as a tem-porary crossing for civilian application. The analysis was carried out for the bridge loaded with a moving vehicle. The results of this analysis have been developed in the form of nomograms that enable rapid development of crossings in different structural systems.[b]Keywords[/b]: civil engineering, folding bridges, floating supports

  5. Bridge Failure Due to Inadequate Design of Bed Protection

    Science.gov (United States)

    Gupta, Yogita; Kaur, Suneet; Dindorkar, Nitin

    2017-12-01

    The shallow foundation is generally provided on non-erodible strata or where scour depth is less. It is also preferable for low perennial flow or standing water condition. In the present case study shallow foundation is adopted for box type bridge. The total length of the bridge is 132.98 m, consisting of eight unit of RCC box. Each unit is composed of three cell box. The bottom slab of box unit is acted as raft foundation, founded 500 mm below ground level. River bed protection work is provided on both upstream and downstream side along the whole length of the bridge as it is founded above scour level. The bridge collapsed during the monsoon just after two years of service. The present paper explains the cause of failure. This study on failure of the bridge illustrates the importance of bridge inspection before and after monsoon period and importance of the timely maintenance. Standard specifications of Indian Road Congress for the river bed protection work are also included.

  6. Salt-bridge networks within globular and disordered proteins: characterizing trends for designable interactions.

    Science.gov (United States)

    Basu, Sankar; Mukharjee, Debasish

    2017-07-01

    There has been considerable debate about the contribution of salt bridges to the stabilization of protein folds, in spite of their participation in crucial protein functions. Salt bridges appear to contribute to the activity-stability trade-off within proteins by bringing high-entropy charged amino acids into close contacts during the course of their functions. The current study analyzes the modes of association of salt bridges (in terms of networks) within globular proteins and at protein-protein interfaces. While the most common and trivial type of salt bridge is the isolated salt bridge, bifurcated salt bridge appears to be a distinct salt-bridge motif having a special topology and geometry. Bifurcated salt bridges are found ubiquitously in proteins and interprotein complexes. Interesting and attractive examples presenting different modes of interaction are highlighted. Bifurcated salt bridges appear to function as molecular clips that are used to stitch together large surface contours at interacting protein interfaces. The present work also emphasizes the key role of salt-bridge-mediated interactions in the partial folding of proteins containing long stretches of disordered regions. Salt-bridge-mediated interactions seem to be pivotal to the promotion of "disorder-to-order" transitions in small disordered protein fragments and their stabilization upon binding. The results obtained in this work should help to guide efforts to elucidate the modus operandi of these partially disordered proteins, and to conceptualize how these proteins manage to maintain the required amount of disorder even in their bound forms. This work could also potentially facilitate explorations of geometrically specific designable salt bridges through the characterization of composite salt-bridge networks. Graphical abstract ᅟ.

  7. Structural design guidelines for concrete bridge decks reinforced with corrosion-resistant reinforcing bars.

    Science.gov (United States)

    2014-10-01

    This research program develops and validates structural design guidelines and details for concrete bridge decks with : corrosion-resistant reinforcing (CRR) bars. A two-phase experimental program was conducted where a control test set consistent : wi...

  8. Bridge scour and stream instability countermeasures : experience, selection, and design guidance : third edition. Volume 1

    Science.gov (United States)

    2009-09-01

    This document identifies and provides design guidelines for bridge scour and stream instability countermeasures that have been implemented by various State departments of transportation (DOTs) in the United States. Countermeasure experience, selectio...

  9. Bridge scour and stream instability countermeasures : experience, selection, and design guidance : third edition. Volume 2

    Science.gov (United States)

    2009-09-01

    This document identifies and provides design guidelines for bridge scour and stream instability countermeasures that have been implemented by various State departments of transportation (DOTs) in the United States. Countermeasure experience, selectio...

  10. Design and evaluation of a single-span bridge using ultra-high performance concrete.

    Science.gov (United States)

    2009-09-01

    "Research presented herein describes an application of a newly developed material called Ultra-High Performance Concrete (UHPC) to a : single-span bridge. The two primary objectives of this research were to develop a shear design procedure for possib...

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

    DEFF Research Database (Denmark)

    Bertelsen, Olav Wedege; Kramp, Gunnar

    2012-01-01

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

  12. FEATURES OF DESIGN OF TIED-ARCH BRIDGES WITH FLEXIBLE INCLINED SUSPENSION HANGERS

    Directory of Open Access Journals (Sweden)

    V. O. Samosvat

    2017-10-01

    Full Text Available Purpose. Investigation and analysis of the hanger arrangement and the structural stability of a Network arch bridge – a tied-arch bridge with inclined hangers that cross each other at least twice. It is also necessary to make a comparative analysis with other types of hanger arrangements. Methodology. The authors in their research investigated a large number of parameters to determine their influence in the force distribution in the arch. Eventually they determined optimal values for all parameters. These optimal values allowed developing a design guide that leads to optimal arch design. When solving this problem, the authors used three-dimensional finite element models and the objective was to determine the most suitable solution for a road bridge, with a span of 100 meters, consisting of two inclined steel arches, located on a road with two traffic lanes, subjected to medium traffic. The virtual prototype of the model is performed by finite element simulator Midas Civil. Findings. In this study, for the bridge deck, a concrete tie appears to be the best solution considering the structural behavior of network arches, but economic advantages caused by easier erection may lead to steel or a composite bridge deck as better alternatives. Design requirements and local conditions of each particular bridge project will decide the most economic deck design.Originality. To ensure passenger comfort and the stability and continuity of the track, deformations of bridges are constricted. A network arch is a stiff structure with small deflections and therefore suitable to comply with such demands even for high speed railway traffic.
A network arch bridge with a concrete tie usually saves more than half the steel required for tied arches with vertical hangers and concrete ties. Practical value. Following the study design advice given in this article leads to savings of about 60 % of structural steel compared with conventional tied arch bridges with

  13. Economic impact of multi-span, prestressed concrete girder bridges designed as simple span versus continuous span : final report.

    Science.gov (United States)

    2016-10-01

    The objective of this study was to determine the economic impact of designing pre-tensioned prestressed concrete beam (PPCB) : bridges utilizing the continuity developed in the bridge deck as opposed to the current Iowa Department of Transportation (...

  14. Economic impact of multi-span, prestressed concrete girder bridges designed as simple span versus continuous span : tech transfer summary.

    Science.gov (United States)

    2016-10-01

    The objective of this study was to determine the economic impact of : designing pre-tensioned prestressed concrete beam (PPCB) bridges : utilizing the continuity developed in the bridge deck as opposed to the : current Iowa Department of Transportati...

  15. Protein thermal stability enhancement by designing salt bridges: a combined computational and experimental study.

    Directory of Open Access Journals (Sweden)

    Chi-Wen Lee

    Full Text Available Protein thermal stability is an important factor considered in medical and industrial applications. Many structural characteristics related to protein thermal stability have been elucidated, and increasing salt bridges is considered as one of the most efficient strategies to increase protein thermal stability. However, the accurate simulation of salt bridges remains difficult. In this study, a novel method for salt-bridge design was proposed based on the statistical analysis of 10,556 surface salt bridges on 6,493 X-ray protein structures. These salt bridges were first categorized based on pairing residues, secondary structure locations, and Cα-Cα distances. Pairing preferences generalized from statistical analysis were used to construct a salt-bridge pair index and utilized in a weighted electrostatic attraction model to find the effective pairings for designing salt bridges. The model was also coupled with B-factor, weighted contact number, relative solvent accessibility, and conservation prescreening to determine the residues appropriate for the thermal adaptive design of salt bridges. According to our method, eight putative salt-bridges were designed on a mesophilic β-glucosidase and 24 variants were constructed to verify the predictions. Six putative salt-bridges leaded to the increase of the enzyme thermal stability. A significant increase in melting temperature of 8.8, 4.8, 3.7, 1.3, 1.2, and 0.7°C of the putative salt-bridges N437K-D49, E96R-D28, E96K-D28, S440K-E70, T231K-D388, and Q277E-D282 was detected, respectively. Reversing the polarity of T231K-D388 to T231D-D388K resulted in a further increase in melting temperatures by 3.6°C, which may be caused by the transformation of an intra-subunit electrostatic interaction into an inter-subunit one depending on the local environment. The combination of the thermostable variants (N437K, E96R, T231D and D388K generated a melting temperature increase of 15.7°C. Thus, this study

  16. The method of rapid design of the folding bridge based on floating supports

    OpenAIRE

    Jan Marszałek; Mieczysław Piechota

    2016-01-01

    The article includes a methodology for the rapid design of the folding bridge based on floating supports. This methodology includes an analysis of the possibilities of using blocks from the park pontoon PP-64 as a support for the floating folding DMS-65 bridge, built as a tem-porary crossing for civilian application. The analysis was carried out for the bridge loaded with a moving vehicle. The results of this analysis have been developed in the form of nomograms that enable rapid development ...

  17. Design, fabrication and erection of Queen Mall Bridge; Queen mall kyo no sekkei seisaku kasetsu

    Energy Technology Data Exchange (ETDEWEB)

    Arai, M.; Ishii, A.; Shinohara, T. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1997-12-20

    This paper describes design, fabrication and erection of Queen Mall Bridge, which is a new landmark in Minato-Mirai Yokohama. This bridge is two-span continuous cable stayed pedestrian bridge with a roof, and has a length 72.2 m, a width 18 m and a weight about 1,050 t. This bridge connects between the Queen`s Square and the second floor of Pacifico Yokohama. Achieving harmonious impression of the newly designed bridge in this area, glass roof was employed and all-weld method was applied to the in-site jointing of main girders and main tower in addition to the essential structural design. Since all-weld method was applied to the in-site jointing, highly accurate fabrication was considered during the in-site jointing. Due to the heavy traffic of the road below the bridge, the erection time was shortened under the severe erection conditions at night by large block method. Especially, accuracy control was considered for the whole shape management. Pre-assemble of all members was conducted just near the erection site, only 500 m away from the site, to shorten the construction time. 1 ref., 5 figs.

  18. Use of interactive graphics in bridge analysis and design.

    Science.gov (United States)

    1983-01-01

    This study evaluated the role of computer-aided design (CAD), including interactive graphics, in engineering design applications, especially in the design activities of the Virginia Department of Highways and Transportation. A review of the hardware ...

  19. Winding design of series AC inductor for dual active bridge converters

    DEFF Research Database (Denmark)

    Shen, Zhan; Wang, Huai; Shen, Yanfeng

    2018-01-01

    The ac resistance and parasitic capacitance of the inductor are the primary considerations in the winding design for the dual-active bridge converter (DAB). They are dependent of up to four independent structure variables. The interactive restrictions between those variables makes the design diff...

  20. Designing a second language bridging course for university students

    Directory of Open Access Journals (Sweden)

    Carol A. Puhl

    2013-02-01

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

  1. Longevity of anterior resin-bonded bridges: survival rates of two tooth preparation designs.

    Science.gov (United States)

    Abuzar, M; Locke, J; Burt, G; Clausen, G; Escobar, K

    2018-04-16

    Significant developments have occurred in the design of resin-bonded bridges (RBB) over the past two decades. They are commonly used as an alternative treatment option for a single missing tooth. The longevity of these bridges needs to be further investigated to evaluate long-term outcomes for this option to remain relevant. A cohort of patients who received anterior resin-bonded bridges (ARBB) over two decades was studied retrospectively. Longevity of 206 ARBB was assessed using Kaplan-Meier probability estimates. The two modified tooth preparation designs investigated were: (A) mesial and distal vertical grooves only; and (B) one proximal groove adjacent to the pontic and two palatal grooves. Age and gender of the patient cohort were also recorded. Overall survival rate of ARBB was 98% at 5 years, 97.2% at 10 years, and 95.1% from 12 years till 21 years. Survival curves showed minor differences when compared for the two designs, age groups and gender of ARBB recipients. Differences in the proportion of surviving bridges for design A (95.96%) and design B (98.13%) were not statistically significant (Fisher's exact test). Anterior RBB with described tooth preparation designs demonstrate a high survival rate. © 2018 Australian Dental Association.

  2. Smart Rocks for Bridge Scour Monitoring: Design and Localization Using Electromagnetic Techniques and Embedded Orientation Sensors

    Science.gov (United States)

    Radchenko, Andro

    River bridge scour is an erosion process in which flowing water removes sediment materials (such as sand, rocks) from a bridge foundation, river beds and banks. As a result, the level of the river bed near a bridge pier is lowering such that the bridge foundation stability can be compromised, and the bridge can collapse. The scour is a dynamic process, which can accelerate rapidly during a flood event. Thus, regular monitoring of the scour progress is necessary to be performed at most river bridges. Present techniques are usually expensive, require large man/hour efforts, and often lack the real-time monitoring capabilities. In this dissertation a new method--'Smart Rocks Network for bridge scour monitoring' is introduced. The method is based on distributed wireless sensors embedded in ground underwater nearby the bridge pillars. The sensor nodes are unconstrained in movement, are equipped with years-lasting batteries and intelligent custom designed electronics, which minimizes power consumption during operation and communication. The electronic part consists of a microcontroller, communication interfaces, orientation and environment sensors (such as are accelerometer, magnetometer, temperature and pressure sensors), supporting power supplies and circuitries. Embedded in the soil nearby a bridge pillar the Smart Rocks can move/drift together with the sediments, and act as the free agent probes transmitting the unique signature signals to the base-station monitors. Individual movement of a Smart Rock can be remotely detected processing the orientation sensors reading. This can give an indication of the on-going scour progress, and set a flag for the on-site inspection. The map of the deployed Smart Rocks Network can be obtained utilizing the custom developed in-network communication protocol with signals intensity (RSSI) analysis. Particle Swarm Optimization (PSO) is applied for map reconstruction. Analysis of the map can provide detailed insight into the scour

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

    DEFF Research Database (Denmark)

    Koss, Holger

    2014-01-01

    In recent years the relevance of ice accretion for wind-induced vibration of structural bridge cables has been recognised and became a subject of research in bridge engineering. Full-scale monitoring and observation indicate that light precipitation at moderate low temperatures between zero and -...... 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........ The determination of these force coefficients require a proper simulation of the ice layer occurring under the specific climatic conditions, favouring real ice accretion over simplified artificial reproduction. The work presented in this paper was performed to study whether the design of bridge cable surface...

  4. Using artificial neural networks in the design of orthotropic bridge decks

    Directory of Open Access Journals (Sweden)

    Ahmed Shamel Fahmy

    2016-12-01

    Full Text Available For orthotropic bridge decks a lot of progress has been made in the development of codes to aid in the design process, in addition to software tools for numerical analysis and design. However, professional software tools will not aid the designer in choosing a preliminary economic layout at the conceptual design stage. Designers would go through iterative, lengthy and expensive procedures to reach the best configuration. The present research provides a methodology to investigate the contingency of using artificial neural networks for conceptual design of orthotropic steel-deck bridge. A neural network model was trained with different combinations of dimensions, and eight types of safety checks were performed on all of them. The resulting network can predict whether the deck is safe or not. It is found that this approach for the selection of orthotropic deck dimensions is a better and cost-effective option compared with international codes or expert opinion.

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

    DEFF Research Database (Denmark)

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

    The ReflecTable is a digital learning environment that explores how design games and video-led reflection might be combined to bridge the gap between the theoretical and practical components of design education. The concept seeks to leverage the qualities of exploratory design games and video...... to inspire design students to critically reflect upon the relationship between their evolving design practices and the theories and techniques they are taught in lectures, by allowing them to capture, review and reflect upon short videos of a design game. In this paper, we present the ReflecTable design...

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

    International Nuclear Information System (INIS)

    Kurusu, T; Ono, M; Ogata, H; Tosaka, T; Senda, I; Nomura, S

    2006-01-01

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

  7. Feature of extradosed PC bridge and its design; Daihenshin keburu PC kyo no tokucho to sono sekkei

    Energy Technology Data Exchange (ETDEWEB)

    Komiya, M. [Japan Bridge and Structure Institute Inc., Tokyo (Japan)

    1997-03-31

    A PC bridge with the eccentricity of the external cable increased by protruding the deviated member to the outside of the beam for more effective use of the external cable is called a `PC bridge with tendons of large eccentricity.` The extradosed bridge of main beam/cable joint type is a PC bridge with the external cable arranged via a tower-shaped eccentric member provided at the intermediate support, and resembles morphologically a cable stayed bridge having a very low tower. There are two types of extradosed bridges, i.e. a type with concrete coated external cable (cable stayed slab bridge) and the other with non-coated external cable (external cable stayed bridge). Features, structural planning and designing of the general external cable stayed bridge are shown. The features are the possession of intermediate characteristics of those of the PC beam bridge and the PC cable stayed bridge from the viewpoints of structural property, workability, economic efficiency, and scenic property. Outline of the plan, selection of structural data, design of the external cable, and structural characteristics in the ultimate state are discussed. 19 refs., 18 figs., 15 tabs.

  8. Learning Based on the Project Entitled "Design and Construction of a Wooden Bridge"

    Science.gov (United States)

    Barris, Cristina; Torres, Lluís; Simon, Enric

    2016-01-01

    This article presents the results of a case involving the application of project-based learning carried out with students in the Mechanical Engineering degree program at the University of Girona. The project, entitled "Design and construction of a wooden bridge", was conducted at the Polytechnic School in the third-year Structures…

  9. Bridge-in-a-Backpack(TM) task 3.1: investigating soil - structure interaction - experimental design.

    Science.gov (United States)

    2015-07-01

    This report includes fulfillment of Task 3.1 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 3 is an investigation of soil-structure interaction for the FRP tubes. Task 3.1 is the : design of...

  10. Learning Axes and Bridging Tools in a Technology-Based Design for Statistics

    Science.gov (United States)

    Abrahamson, Dor; Wilensky, Uri

    2007-01-01

    We introduce a design-based research framework, "learning axes and bridging tools," and demonstrate its application in the preparation and study of an implementation of a middle-school experimental computer-based unit on probability and statistics, "ProbLab" (Probability Laboratory, Abrahamson and Wilensky 2002 [Abrahamson, D., & Wilensky, U.…

  11. Values in Design - Building Bridges between RE, HCI and Ethics

    OpenAIRE

    Detweiler , Christian; Pommeranz , Alina; Hoven , Jeroen; Nissenbaum , Helen

    2011-01-01

    Part 1: Long and Short Papers; International audience; Designing for values has become increasingly important for technology development. In many technological systems (medical applications, social networks etc.) values (privacy, autonomy, trust etc.) play a role and are sometimes violated. In working with stakeholder requirements or user needs, various design methods in requirements engineering (RE) [3] and human computer interaction (HCI), in specific user-centered (UCD), deal with “soft is...

  12. CF60 Concrete Composition Design and Application on Fudiankou Xijiang Super Large Bridge

    Science.gov (United States)

    Qiu, Yi Mei; Wen, Sen Yuan; Chen, Jun Xiang

    2018-06-01

    Guangxi Wuzhou City Ring Road Fudiankou Xijiang super large bridge CF60 concrete is a new multi-phase composite high-performance concrete, this paper for the Fudiankou Xijiang bridge structure and characteristics of the project, in accordance with the principle of local materials and technical specification requirements, combined with the site conditions of CF60 engineering high performance concrete component materials, proportion and the technical performance, quantify the main physical and mechanical performance index. Analysis main influencing factors of the technical indicators, reasonable adjustment of concrete mix design parameters, and the use of technical means of admixture and multi-function composite admixture of concrete, obtain the optimal proportion of good work, process, mechanical properties stability and durability of engineering properties, recommend and verification of concrete mix; to explore the CF60 high performance concrete Soil in the Fudiankou Xijiang bridge application technology, detection and tracking the quality of concrete construction, concrete structure during the construction of the key technology and control points is proposed, evaluation of CF60 high performance concrete in the actual engineering application effect and benefit to ensure engineering quality of bridge structure and service life, and super long span bridge engineering construction to provide basis and reference.

  13. A Review of Multi-Criteria Decision-Making Methods Applied to the Sustainable Bridge Design

    Directory of Open Access Journals (Sweden)

    Vicent Penadés-Plà

    2016-12-01

    Full Text Available The construction of bridges has been necessary for societies since ancient times, when the communication between and within towns, cities or communities was established. Until recently, the economic factor has been the only one considered in the decision-making of any type of construction process for bridges. However, nowadays, the objective should not be just the construction of bridges, but of sustainable bridges. Economic, social and environmental factors, which form the three pillars of sustainability, have been recently added. These three factors usually have conflicting perspectives. The decision-making process allows the conversion of a judgment into a rational procedure to reach a compromise solution. The aim of this paper is to review different methods and sustainable criteria used for decision-making at each life-cycle phase of a bridge, from design to recycling or demolition. This paper examines 77 journal articles for which different methods have been used. The most used methods are briefly described. In addition, a statistical study was carried out on the Multiple Attribute Decision-making papers reviewed.

  14. Designing for knowledge: bridging socio-hydrological monitoring and beyond

    Science.gov (United States)

    Mao, F.; Clark, J.; Buytaert, W.; Ochoa-Tocachi, B. F.; Hannah, D. M.

    2016-12-01

    Many methods and applications have been developed to research socio-hydrological systems, such as participatory monitoring, environmental big data processing and sensor network data transmission. However, these data-centred activities are insufficient to guarantee successful knowledge co-generation, decision making or governance. This research suggests a shift of attentions in designing socio-hydrological monitoring tools, from designing for data to designing for knowledge (DfK). Compared to the former strategy, DfK has at least three features as follows. (1) Why monitor? DfK demands the data produced by the newly introduced monitoring application to have potentials to generate socio-hydrological knowledge that supports decision making or management. It means that when designing a monitoring tool, we should not only answer how to collect data, but also questions such as how to best use the collected data in the form of knowledge. (2) What is the role of monitoring? DfK admits that the socio-hydrological data and knowledge generated by monitoring is just one of many kinds to support decision making and management. It means that the importance of monitoring and scientific evidence should not be overestimated, and knowledge cogeneration and synthesis should be considered in advance in the monitoring design process. (3) Who participate? DfK implies a wider engagement of stakeholders, which is not restricted between volunteers as data collectors and providers, and scientist and researcher communities as main data users. It requires a broader consideration of users, including not only data collectors, processors and interpreters, but also local and indigenous knowledge providers, and decision makers who use the knowledge and data. In summary, this research proposes a knowledge-centred strategy in designing participatory socio-hydrological monitoring tools, in order to make monitoring more useful and effective.

  15. Computational manufacturing as a bridge between design and production.

    Science.gov (United States)

    Tikhonravov, Alexander V; Trubetskov, Michael K

    2005-11-10

    Computational manufacturing of optical coatings is a research area that can be placed between theoretical designing and practical manufacturing in the same way that computational physics can be placed between theoretical and experimental physics. Investigations in this area have been performed for more than 30 years under the name of computer simulation of manufacturing and monitoring processes. Our goal is to attract attention to the increasing importance of computational manufacturing at the current state of the art in the design and manufacture of optical coatings and to demonstrate possible applications of this research tool.

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

    NARCIS (Netherlands)

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

    2010-01-01

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

  17. Complementarity and Compensation: Bridging the Gap between Writing and Design.

    Science.gov (United States)

    Killingsworth, M. Jimmie; Sanders, Scott P.

    1990-01-01

    Outlines two rhetorical principles for producing iconic-mosaic texts--the principle of complementarity and the principle of compensation. Shows how these principles can be applied to practical problems in coordinating the writing and design processes in student projects. (RS)

  18. Affordability Engineering: Bridging the Gap Between Design and Cost

    Science.gov (United States)

    Reeves, J. D.; DePasquale, Dominic; Lim, Evan

    2010-01-01

    Affordability is a commonly used term that takes on numerous meanings depending on the context used. Within conceptual design of complex systems, the term generally implies comparisons between expected costs and expected resources. This characterization is largely correct, but does not convey the many nuances and considerations that are frequently misunderstood and underappreciated. In the most fundamental sense, affordability and cost directly relate to engineering and programmatic decisions made throughout development programs. Systems engineering texts point out that there is a temporal aspect to this relationship, for decisions made earlier in a program dictate design implications much more so than those made during latter phases. This paper explores affordability engineering and its many sub-disciplines by discussing how it can be considered an additional engineering discipline to be balanced throughout the systems engineering and systems analysis processes. Example methods of multidisciplinary design analysis with affordability as a key driver will be discussed, as will example methods of data visualization, probabilistic analysis, and other ways of relating design decisions to affordability results.

  19. Get synchronized : Bridging the gap between design and volume production

    NARCIS (Netherlands)

    Smulders, F.E.H.M.

    2006-01-01

    The interface between Design and Manufacturing forms a locus of frequent interpersonal conflict. Misunderstandings, unwelcome surprises and planning problems are the rule rather than the exception. Within companies that deliver consumer goods in large quantities to the market this interface is also

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

    Directory of Open Access Journals (Sweden)

    Raymond E. Levitt

    2012-08-01

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

  1. Hybrid design tools for conceptual design and design engineering processes: bridging the design gap: towards an intuitive design tool

    NARCIS (Netherlands)

    Wendrich, Robert E.

    2016-01-01

    Hybrid Design Tools; Representation; Computational Synthesis. Non-linear, non-explicit, non-standard thinking and ambiguity in design tools has a great impact on enhancement of creativity during ideation and conceptualization. Tacit-tangible representation based on a mere idiosyncratic and

  2. Design and construction of Chiburiko Bridge (stress ribbon bridge). Chiburiko bashi (tsurishoban kyo) no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Kamisakoda, K; Tokuyama, S; Sano, K; Onuma, K [Kashima Corp., Tokyo (Japan)

    1992-07-30

    Chiburiko Bridge lies across Chiburiko which is a lake for agricultural water, and is used by people, carts and cars for administration. It is a stressed-ribbon bridge with the road surface made with concrete covered bands of cables stretched between abutments, and is the first highway bridge in Japan. A report is made on the plan and construction of the bridge. Integration of the precast slab with the cast-in-place concrete as well as mutual integration of the precast slabs are validated by the use of a reproduced model of a part of the bridge. Floor slabs are suspended by cables, and can be constructed with no form nor support by integrating cast-in-place concrete with the precast slabs on mutually joined precast slabs. It has been said that the stressed-ribbon bridge has a structure suitable for long span bridges because it has a simple structure. Studies, however, seems to be necessary on the impact caused by running of vehicles and on the wind resisting stability. 3 refs., 17 figs., 2 tabs.

  3. Classical and Modern Design Solutions in Conceptual Design of a Pedestrian Bridge over Vistula River in Cracow

    Science.gov (United States)

    Ryż, Karol; Pańtak, Marek

    2017-10-01

    In the paper the design concept of the steel pedestrian bridge over Vistula river in Cracow, Poland has been characterised. The footbridge was designed as a truss structure with steel pipes, Warren truss configuration, arched bottom chord and spans 15.5+120.0+15.5 m. Intensive tourist traffic around the Wawel Castle in Cracow, directed towards the historic Kazimierz district, Wawel Hill and the Old Town Market Place requires the creation of a bridge structure over the Vistula River that will meet both the communication and recreation functions. An additional aim was to design a structure which architectural form will not unduly and negatively interfere in the environment and will join the technical capabilities of the XXI century with the charm of nearby historic buildings.

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

    International Nuclear Information System (INIS)

    Stredde, H.J.

    1991-01-01

    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.

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

    Science.gov (United States)

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

    2012-09-01

    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.].

  6. Access Bridge Design Measures for Safety Increase of the Road Infrastructure

    Directory of Open Access Journals (Sweden)

    Tomas Micunek

    2013-12-01

    Full Text Available Solid barriers represent danger for the driver in case of traffic lane escape. This threat can be represented by a drainage ditch culvert face. The access bridge is not usually conspicuous enough near the traffic lane so that the driver could ditch and crash this barrier in case of an exceptional situation such as avoidance manoeuvres. This work deals with a technical solution of access bridges with an integrated deformation zone which was designed on the ground of a detailed analysis of current types of the construction. The new technical solution was proved by means of a numerical simulation of passenger car impact and compared with the current design of culvert faces.

  7. A Cost-Effective Design and Analysis of Full Bridge LLC Resonant Converter

    OpenAIRE

    Kaibalya Prasad Panda; Sreyasee Rout

    2016-01-01

    LLC (Inductor-inductor-capacitor) resonant converter has lots of advantages over other type of resonant converters which include high efficiency, more reliable and have high power density. This paper presents the design and analysis of a full bridge LLC resonant converter. In addition to the operational principle, the ZVS and ZCS conditions are also explained with the DC characteristics. Simulation of the LLC resonant converter is performed in MATLAB/ Simulink and the practical prototype setu...

  8. Bridging the Gap: A Design-based Case Study of a Mathematics Skills Intervention Program

    OpenAIRE

    Safaralian, Leila

    2017-01-01

    Abstract of the DissertationBridge the Gap: A Design-based Case Study of a Mathematics Skills Intervention ProgrambyLeila SafaralianDoctor of Education in Educational LeadershipUniversity of California, San Diego, 2017California State University, San Marcos, 2017Kenneth P. Gonzalez, ChairMany students aspire to continue their educational journey, but far too many enter college without the basic content knowledge, skills, or habits of mind needed to succeed. Research on college readiness indic...

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

    Energy Technology Data Exchange (ETDEWEB)

    Husemoen, Mette Suzanne

    1998-12-31

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Husemoen, Mette Suzanne

    1997-12-31

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    International Nuclear Information System (INIS)

    Kim, Tae Wan; Park, Keun Bae; Choi, Suhn; Kim, Kang Soo; Jeong, Kyeong Hoon; Lee, Gyu Mahn

    1998-09-01

    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

  13. Complex Method Mixed with PSO Applying to Optimization Design of Bridge Crane Girder

    Directory of Open Access Journals (Sweden)

    He Yan

    2017-01-01

    Full Text Available In engineer design, basic complex method has not enough global search ability for the nonlinear optimization problem, so it mixed with particle swarm optimization (PSO has been presented in the paper,that is the optimal particle evaluated from fitness function of particle swarm displacement complex vertex in order to realize optimal principle of the largest complex central distance.This method is applied to optimization design problems of box girder of bridge crane with constraint conditions.At first a mathematical model of the girder optimization has been set up,in which box girder cross section area of bridge crane is taken as the objective function, and its four sizes parameters as design variables, girder mechanics performance, manufacturing process, border sizes and so on requirements as constraint conditions. Then complex method mixed with PSO is used to solve optimization design problem of cane box girder from constrained optimization studying approach, and its optimal results have achieved the goal of lightweight design and reducing the crane manufacturing cost . The method is reliable, practical and efficient by the practical engineer calculation and comparative analysis with basic complex method.

  14. Collision loads on bridge piers : phase 2, report of guidelines for designing bridge piers and abutments for vehicle collisions

    Science.gov (United States)

    2011-03-01

    An instrumented, simulated bridge pier was constructed, and two full-scale collisions with an : 80,000-lb van-type tractor-trailer were performed on it. The trailer was ballasted with bags of sand on : pallets. The simulated pier was 36 inches in dia...

  15. Design and fabrication of piezoresistive p-SOI Wheatstone bridges for high-temperature applications

    Science.gov (United States)

    Kähler, Julian; Döring, Lutz; Merzsch, Stephan; Stranz, Andrej; Waag, Andreas; Peiner, Erwin

    2011-06-01

    For future measurements while depth drilling, commercial sensors are required for a temperature range from -40 up to 300 °C. Conventional piezoresistive silicon sensors cannot be used at higher temperatures due to an exponential increase of leakage currents which results in a drop of the bridge voltage. A well-known procedure to expand the temperature range of silicon sensors and to reduce leakage currents is to employ Silicon-On-Insulator (SOI) instead of standard wafer material. Diffused resistors can be operated up to 200 °C, but show the same problems beyond due to leakage of the p-njunction. Our approach is to use p-SOI where resistors as well as interconnects are defined by etching down to the oxide layer. Leakage is suppressed and the temperature dependence of the bridges is very low (TCR = (2.6 +/- 0.1) μV/K@1 mA up to 400 °C). The design and process flow will be presented in detail. The characteristics of Wheatstone bridges made of silicon, n- SOI, and p-SOI will be shown for temperatures up to 300 °C. Besides, thermal FEM-simulations will be described revealing the effect of stress between silicon and the silicon-oxide layer during temperature cycling.

  16. Design and construction of Chichibu-park bridge. Chichibu Koenkyo (kasho) no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Hasuike, H.; Azami, Y. (Saitama Prefectural Government Office, Saitama (Japan) New Structural Engineering, Ltd., Tokyo (Japan)); Yamamoto, T.

    1994-01-31

    The design and construction of the Chichibu-Park Bridge in Japan were outlined which is the symmetric 2-span continuous PC cable stayed road bridge with one main tower (530 m in total length, 392 m in main bridge length, 19 m in width) built over the Arakawa River. The double-suspended four-box main girder with wind noses was adopted because of its excellent torsional rigidity of area and wind proof stability, and the rigid-frame main girder was rigidly connected to the middle main tower. The main tower with an H-type hollow section was adopted considering its workability, and was assembled with its divided 18 blocks. Each side of the main girder was suspended at 30 points spaced at 6.0 m, and the tower ends of the diagonal cables were fixed to the partition inside the main tower taking a landscape into account. The thick stranded wires composed of fine PC steel stranded wires and covered with polyethylene were adopted as diagonal cables, and structural beams were used for both ends of the diagonal cables. Damping wires were also adopted to damp the diagonal cables. 9 refs., 12 figs., 6 tabs.

  17. Improved Simplified Methods for Effective Seismic Analysis and Design of Isolated and Damped Bridges in Western and Eastern North America

    Science.gov (United States)

    Koval, Viacheslav

    The seismic design provisions of the CSA-S6 Canadian Highway Bridge Design Code and the AASHTO LRFD Seismic Bridge Design Specifications have been developed primarily based on historical earthquake events that have occurred along the west coast of North America. For the design of seismic isolation systems, these codes include simplified analysis and design methods. The appropriateness and range of application of these methods are investigated through extensive parametric nonlinear time history analyses in this thesis. It was found that there is a need to adjust existing design guidelines to better capture the expected nonlinear response of isolated bridges. For isolated bridges located in eastern North America, new damping coefficients are proposed. The applicability limits of the code-based simplified methods have been redefined to ensure that the modified method will lead to conservative results and that a wider range of seismically isolated bridges can be covered by this method. The possibility of further improving current simplified code methods was also examined. By transforming the quantity of allocated energy into a displacement contribution, an idealized analytical solution is proposed as a new simplified design method. This method realistically reflects the effects of ground-motion and system design parameters, including the effects of a drifted oscillation center. The proposed method is therefore more appropriate than current existing simplified methods and can be applicable to isolation systems exhibiting a wider range of properties. A multi-level-hazard performance matrix has been adopted by different seismic provisions worldwide and will be incorporated into the new edition of the Canadian CSA-S6-14 Bridge Design code. However, the combined effect and optimal use of isolation and supplemental damping devices in bridges have not been fully exploited yet to achieve enhanced performance under different levels of seismic hazard. A novel Dual-Level Seismic

  18. Enhancing the hermeneutic single-case efficacy design: Bridging the research-practice gap.

    Science.gov (United States)

    Wall, Jessie M; Kwee, Janelle L; Hu, Monica; McDonald, Marvin J

    2017-09-01

    Systematic case study designs are emerging as alternative paradigm strategies for psychotherapy and social science research. Through enhanced sensitivity to context, these designs examine idiographic profiles of causal processes. We specifically advocate the use of the hermeneutic single-case efficacy design (HSCED). HSCED has recently been used to investigate the efficacy of an existing therapy with a new population (Observed and Experiential Integration for athlete performance barriers) and an emerging therapy (Lifespan Integration Therapy). We describe innovations in HSCED that were implemented for these studies. These developments include (a) integrating psychotherapists as case developers, (b) incorporating multiple cases in one investigation, and (c) tailoring the repertoire of assessment tools. These extensions strategically incorporated principles of contextual paradigms in HSCED, thus complementing single-case designs that neglect idiographic contexts. We discuss recommendations for using HSCED in practice-based research, highlighting its potential as a bridge to address the research-practice gap.

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

    International Nuclear Information System (INIS)

    Hasibuan, D.

    1999-01-01

    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

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

    International Nuclear Information System (INIS)

    Sitompul, Aristarkus

    2000-01-01

    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 47.25 i n length and a peace of steel plate by 111.82 x 47.25 x 0,394 . This paper concluded that this design is feasible to be fabricated

  1. Comparative design of the superstructure of timber bridges, using norm np 005 - 2003 and provisions of european standards

    Directory of Open Access Journals (Sweden)

    Chiotan Corina

    2015-12-01

    Full Text Available The norms and standards for design of timber bridges, as well as other structures built from this material, were obsolete, design standards that were used dated from 1978 to 1980. The introduction of European Standards has created a new legislative framework in the field of designing and building timber bridges. Currently the design of such constructions use Norm NP 005-2003 and SR EN 1995-1-1: 2004 Eurocode 5: Design of timber structures. Part 1-1: General. Common rules and rules for buildings, SR EN 1995-2: 2005 Eurocode 5: Design of timber structures. Part 2: Bridges, along with their national annexes. The aim of this paper is to analyze the design of the beams for timber bridges in parallel, using on one hand Norm NP 005 - 2003, and on the other hand provisions of European standards. The design requirements for both norms as well as the results of a case study for a structural element of a timber bridge will be presented.

  2. Analysis and Design of a Wireless Power Transfer System with Dual Active Bridges

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2017-10-01

    Full Text Available Nowadays, work on Wireless Power Transfer (WPT systems with dual active bridges is attracting great attention due to their low conduction losses, power regulation, load transformation and reactance compensation. However, in these studies limitations such as overall analysis, design and realization techniques of the system were not considered properly. To address the aforementioned issues, this paper presents a detailed analysis, design and realization of a Series-Series (SS WPT system with dual active bridges, which will improve the overall performance. Three independent Phase Angles (PAs have been analyzed and designed in this study, one PA on the primary side and the other two PAs on the secondary side. This Multiple Degrees of Phase Control (MDPC method can achieve additional reactance compensation, load transformation and output regulation simultaneously. To realize the proposed method in practice, key implementation techniques have been investigated in detail, including additional reactance estimation, mutual inductance estimation, phase detection and synchronization. The feasibility and effectiveness of the proposed system is verified through simulation and experimental results.

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

    Directory of Open Access Journals (Sweden)

    Weiss Mathieu

    2015-01-01

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

  4. Design of fuelling machine bridge and carriage to meet seismic qualification requirements

    International Nuclear Information System (INIS)

    Ghare, A.B.; Chhatre, A.G.; Vyas, A.K.; Bhambra, H.S.

    1996-01-01

    During each refuelling operation, the boundary of Primary heat transport system is extended up to Fuelling Machines. A breach in the pressure boundary of Fuelling Machine in this condition would cause a loss of coolant accident. Fuelling Machines are also used for transit storage of spent fuel bundles till discharged to fuel transfer system. Therefore, a fuelling machine, including its support structures, is required to be seismically qualified for both on-reactor ( coupled ) mode and off-reactor (uncoupled) mode. The fuelling machine carriage used in the first generation of Indian PHWRs is a mobile equipment on wheels moving over fixed rails. As this configuration was found unsuitable for withstanding strong seismic disturbances, a bridge type design with fixed columns was evolved for the next generation of reactors. Initially, the seismic analysis of the fuelling machine bridge and carriage was done using static structural analysis and values of natural frequencies for various structures were computed. The structures were suitably modified based on the results of this analysis. Subsequently, a detailed dynamic seismic analysis using finite element model has been completed for both coupled and uncoupled conditions. The qualification of the structure has been carried out as per ASME section 111 Division 1, sub section NF. Details of the significant design features, static and dynamic analysis, results and conclusions are given in the presentation. (author). 4 refs., 4 tabs., 7 figs

  5. Design of fuelling machine bridge and carriage to meet seismic qualification requirements

    Energy Technology Data Exchange (ETDEWEB)

    Ghare, A B; Chhatre, A G; Vyas, A K; Bhambra, H S [Nuclear Power Corporation of India Ltd., Mumbai (India)

    1997-12-31

    During each refuelling operation, the boundary of Primary heat transport system is extended up to Fuelling Machines. A breach in the pressure boundary of Fuelling Machine in this condition would cause a loss of coolant accident. Fuelling Machines are also used for transit storage of spent fuel bundles till discharged to fuel transfer system. Therefore, a fuelling machine, including its support structures, is required to be seismically qualified for both on-reactor ( coupled ) mode and off-reactor (uncoupled) mode. The fuelling machine carriage used in the first generation of Indian PHWRs is a mobile equipment on wheels moving over fixed rails. As this configuration was found unsuitable for withstanding strong seismic disturbances, a bridge type design with fixed columns was evolved for the next generation of reactors. Initially, the seismic analysis of the fuelling machine bridge and carriage was done using static structural analysis and values of natural frequencies for various structures were computed. The structures were suitably modified based on the results of this analysis. Subsequently, a detailed dynamic seismic analysis using finite element model has been completed for both coupled and uncoupled conditions. The qualification of the structure has been carried out as per ASME section 111 Division 1, sub section NF. Details of the significant design features, static and dynamic analysis, results and conclusions are given in the presentation. (author). 4 refs., 4 tabs., 7 figs.

  6. Design and construction of Ogawa bridge; Ogawa bashi no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Hori, T.; Chigira, F. [Kajima Corp., Tokyo (Japan); Sakao, H.

    1995-09-30

    Ogawa bridge 230m long by 15.5m wide has been planned on the national road No.401 at Katashina-mura in Gunma Prefecture. Structure mode is two spans continuous PC cable-stayed obliquely system, and a main tower is H type (height: 56m from the road surface) and is located at the center of the bridge alone. This place corresponding to the entrance of Oze famous national park, the main tower is designed so as to have bulge, imaging Mizubasho (lysichiton camtschatcense), from the middle part of the pier to the lower part of the main tower. Arrangement of the cables is designed as two faces of hung fun type and one side face is composed of 13 steel strands (dia. 15.2mm wire x 27 (partly 19); covered with PE tube) in front and rear respectively. A main girder is the box type PC block 2.3m height by 4m or 3m long, and 3m long one is for fastening with a cable. Centering on the main tower, the girder blocks are successively connected in front and rare alternatively and are fastened with cables in part. This overhanging connection work is carried out by two special movable conveyers `Wagens`. 26 figs., 2 tabs.

  7. Abrasion-resistant concrete mix designs for precast bridge deck panels.

    Science.gov (United States)

    2010-08-01

    The report documents laboratory investigations undertaken to develop high performance concrete (HPC) for precast and pre-stressed bridge deck components that would reduce the life-cycle cost of bridges by improving the studded tire wear (abrasion) re...

  8. Evaluation of concrete bridge mix designs for control of cracking, phase I.

    Science.gov (United States)

    2014-11-01

    Cracking of concrete is a common problem with concrete structures such as bridge decks, pavements and bridge : rail. The Agency of Transportation (VTrans) has recently invested in higher performing concrete mixes that are : more impervious and has hi...

  9. INVESTIGATION OF SEISMIC PERFORMANCE AND DESIGN OF TYPICAL CURVED AND SKEWED BRIDGES IN COLORADO

    Science.gov (United States)

    2018-01-15

    This report summarizes the analytical studies on the seismic performance of typical Colorado concrete bridges, particularly those with curved and skewed configurations. A set of bridge models with different geometric configurations derived from a pro...

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

    Directory of Open Access Journals (Sweden)

    Matevž Juvančič

    2012-01-01

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

  11. Simple heuristics: A bridge between manual core design and automated optimization methods

    International Nuclear Information System (INIS)

    White, J.R.; Delmolino, P.M.

    1993-01-01

    The primary function of RESCUE is to serve as an aid in the analysis and identification of feasible loading patterns for LWR reload cores. The unique feature of RESCUE is that its physics model is based on some recent advances in generalized perturbation theory (GPT) methods. The high order GPT techniques offer the accuracy, computational efficiency, and flexibility needed for the implementation of a full range of capabilities within a set of compatible interactive (manual and semi-automated) and automated design tools. The basic design philosophy and current features within RESCUE are reviewed, and the new semi-automated capability is highlighted. The online advisor facility appears quite promising and it provides a natural bridge between the traditional trial-and-error manual process and the recent progress towards fully automated optimization sequences. (orig.)

  12. Analysis and modelling composite timber-concrete systems: Design of bridge structure according to EN

    Directory of Open Access Journals (Sweden)

    Manojlović Dragan

    2016-01-01

    Full Text Available Timber-concrete composite structures are already applied more than 80 years in engineering practice, went trought the intuitive problem solution to the fully prefabricated hybride assemblies for dry building. The development path of timber-concrete composites was always followed by extensive theoretical and experimental research, whose results were successfully implemented in practice, i.e. on the market, but till presence didn't result in modern designer's code. In expectation of new European codes for timber-concrete composites, the objective of the paper is to provide a comprehensive review of available standards provisions and recent conclusions from literature. The key issues for practical design are highlighted and ilustrated on the example of glulam composite arch bridge structure with concrete deck, according the Eurocodes.

  13. Species Identification and Design Value Estimation of Wooden Members in Covered Bridges

    Science.gov (United States)

    Alex C. Wiedenhoeft; David E. Kretschmann

    2014-01-01

    Covered timber bridges are historic structures with unique aesthetic value. To preserve this value and maintain bridges in service, robust evaluation of their performance and safety is necessary. The strength of the timber found in covered bridges can vary considerably, not only because of age and condition, but also because of species and grade. For the practicing...

  14. Design and Fabrication of Full Wheatstone-Bridge-Based Angular GMR Sensors

    Directory of Open Access Journals (Sweden)

    Shaohua Yan

    2018-06-01

    Full Text Available Since the discovery of the giant magnetoresistive (GMR effect, GMR sensors have gained much attention in last decades due to their high sensitivity, small size, and low cost. The full Wheatstone-bridge-based GMR sensor is most useful in terms of the application point of view. However, its manufacturing process is usually complex. In this paper, we present an efficient and concise approach to fabricate a full Wheatstone-bridge-based angular GMR sensor by depositing one GMR film stack, utilizing simple patterned processes, and a concise post-annealing procedure based on a special layout. The angular GMR sensor is of good linear performance and achieves a sensitivity of 0.112 mV/V/Oe at the annealing temperature of 260 °C in the magnetic field range from −50 to +50 Oe. This work provides a design and method for GMR-sensor manufacturing that is easy for implementation and suitable for mass production.

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

    Directory of Open Access Journals (Sweden)

    Rizal Sebastian

    2013-01-01

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

  16. Design and Implementation of Half-Bridge LLC Resonant Converter by FHA Technique

    Directory of Open Access Journals (Sweden)

    Navid Salehi

    2015-07-01

    Full Text Available Although in existence for many years, only recently has the LLC resonant converters, in particular in its half-bridge implementation, gained in the popularity it certainly deserve. The advantages such as high efficiency, low level of EMI emissions, and its ability to achieve high power density are such features that suited for power supply demand of many modern applications such as ATX PCs and flat panel TVs. One of the major difficulties in concern with designing such converter is complex model and non-linear equations that cannot be easily used into a design procedure. So in this paper, design is based on the assumption that input-to-output power transfer is essentially due to the fundamental Fourier series components of currents and voltages. This technique known as First Harmonic Approximation (FHA and is a proper method to obtain the voltage gain through solving the equivalent ac circuit of the resonant tank. The design simulated by Pspice and finally the experimental results show design procedure base on FHA technique.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kilic, Recai [Erciyes University, Department of Electrical and Electronic Engineering, 38039 Kayseri (Turkey)], E-mail: kilic@erciyes.edu.tr; Yildirim, Fatma [Erciyes University, Civil Aviation School, 38039 Kayseri (Turkey)

    2008-12-15

    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.

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

    International Nuclear Information System (INIS)

    Kilic, Recai; Yildirim, Fatma

    2008-01-01

    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

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

    OpenAIRE

    Lan, Cheng

    2012-01-01

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

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

    Science.gov (United States)

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

    2016-06-01

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

  1. Bridging the Gap: A Manual Primer into Design Computing in the Context of Basic Design Education

    Science.gov (United States)

    Uysal, V. Safak; Topaloglu, Fulden

    2017-01-01

    Design education is in need of a wider restructuring to accommodate new developments and paradigmatic shifts brought forth by the information age, all of which capitalise a move towards complexity theory, systems science and digital technologies. The intention of this article is to approach one particular aspect of this need: that is, how basic…

  2. Bridging the Design Gap: Towards an intuitive Design Tool (CD ROM)

    NARCIS (Netherlands)

    Wendrich, Robert E.; Tragter, Hendrik; Kokkeler, Frans; van Houten, Frederikus J.A.M.

    2009-01-01

    A main task of industrial designers is the shaping and transformations of ideas or fuzzy notions into abstract or materialized equivalents. These sketches, models or other representations can be described as the sum of form and shape aspects, aesthetics, intuitive qualities as well as technical and

  3. Skewed steel bridges, part ii : cross-frame and connection design to ensure brace effectiveness : technical summary.

    Science.gov (United States)

    2017-08-01

    Skewed bridges in Kansas are often designed such that the cross-frames are carried parallel to the skew angle up to 40, while many other states place cross-frames perpendicular to the girder for skew angles greater than 20. Skewed-parallel cross-...

  4. Skewed steel bridges, part ii : cross-frame and connection design to ensure brace effectiveness : final report.

    Science.gov (United States)

    2017-08-01

    Skewed bridges in Kansas are often designed such that the cross-frames are carried parallel to the skew angle up to 40, while many other states place cross-frames perpendicular to the girder for skew angles greater than 20. Skewed-parallel cross-...

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

    International Nuclear Information System (INIS)

    Sun Yan; Ye Mei; Zhang Nan; Zhao Jingwei

    2000-01-01

    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

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

    International Nuclear Information System (INIS)

    Sun Yan; Ye Mei; Zhang Nan; Zhao Jingwei

    2001-01-01

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

    DEFF Research Database (Denmark)

    Halding, Philip Skov

    2016-01-01

    a filling layer of lower stiffness above the arches to level the road surface. The present Ph.D. thesis is part of a larger development project about Pearl‐Chain Bridges funded by Innovationsfonden. The project also included another Ph.D. study about the developed materials used in Pearl‐Chain Bridges...

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

    DEFF Research Database (Denmark)

    Du, Guangli; Karoumi, Raid

    2013-01-01

    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 g...

  9. Comparison Between PCI and Box Girder in BridgesPrestressed Concrete Design

    Science.gov (United States)

    Rahmawati, Cut; Zainuddin, Z.; Is, Syafridal; Rahim, Robbi

    2018-04-01

    This research is done by comparing PCI and Box Girder types of prestressed concrete design. The method used is load balance. Previous studies have just discussed the differences in terms of effectiveness and economics. In this study, the researchers want to know the design process by comparing the working forces, the resulting moment, and the losses of the prestressed. As the case in this study, the researchers used the bridge with the span of 31 meters. The tendon pulling system was conducted with post-tensioning system The analysis result showed that prestressed of the Girder box type sustained the greatest moment due to the combination of its own weight, additional dead load, lane load, and wind load of 44,029 kNm, while the biggest moment of PCI Girder was 7,556.75 KNm The Girder beam box experiences greater moment and shear force than PCI Girder. This is the effect of the weight of its own Girderboxwaslarger than PCI Girder. The losses ofprestressed style of Girderboxand PCI Girder type were 24.85% and 26.32%, respectively.Moreover, it showed that the type of Girder box is cheaper, easier, and more efficient than PCI Girder.

  10. Rating of Dynamic Coefficient for Simple Beam Bridge Design on High-Speed Railways

    Science.gov (United States)

    Diachenko, Leonid; Benin, Andrey; Smirnov, Vladimir; Diachenko, Anastasia

    2018-06-01

    The aim of the work is to improve the methodology for the dynamic computation of simple beam spans during the impact of high-speed trains. Mathematical simulation utilizing numerical and analytical methods of structural mechanics is used in the research. The article analyses parameters of the effect of high-speed trains on simple beam spanning bridge structures and suggests a technique of determining of the dynamic index to the live load. Reliability of the proposed methodology is confirmed by results of numerical simulation of high-speed train passage over spans with different speeds. The proposed algorithm of dynamic computation is based on a connection between maximum acceleration of the span in the resonance mode of vibrations and the main factors of stress-strain state. The methodology allows determining maximum and also minimum values of the main efforts in the construction that makes possible to perform endurance tests. It is noted that dynamic additions for the components of the stress-strain state (bending moments, transverse force and vertical deflections) are different. This condition determines the necessity for differentiated approach to evaluation of dynamic coefficients performing design verification of I and II groups of limiting state. The practical importance: the methodology of determining the dynamic coefficients allows making dynamic calculation and determining the main efforts in split beam spans without numerical simulation and direct dynamic analysis that significantly reduces the labour costs for design.

  11. Design of pedestrian truss bridge with Sengon-Rubber laminated veneer lumber

    Science.gov (United States)

    Herbudiman, B.; Pranata, Y. A.; Pangestu, L.

    2017-12-01

    Timber bridges are one of the bridge that has long been used, but nowadays, large dimension of sawn timber has limited supply and also it is not environmental-friendly. Laminated veneer lumber (LVL) is a engineered wood that becomes one of the promising alternative, because it is made from lower quality wood that processed to be used as a more quality one. The bridge planned to be a pedestrian truss bridge with length of 9 m, width of 3 m, height of 2.5 m, and using bolt and steel plate as its connection system. Mechanical properties of LVL obtained directly from laboratory test result. Bridge modeling and planning for wood construction refers to SNI 7973:2013, while the loading refers to SNI 1725:2016. Based on the modelling and calculation, the dimension of truss frame and girder beam which are 9 cm x 9 cm and 9 cm x 18 cm have adequate strengths and satisfy deflection requirement.

  12. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

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

  13. Engineering nutritious proteins: improvement of stability in the designer protein MB-1 via introduction of disulfide bridges.

    Science.gov (United States)

    Doucet, Alain; Williams, Martin; Gagnon, Mylene C; Sasseville, Maxime; Beauregard, Marc

    2002-01-02

    Protein design is currently used for the creation of new proteins with desirable traits. In this laboratory the focus has been on the synthesis of proteins with high essential amino acid content having potential applications in animal nutrition. One of the limitations faced in this endeavor is achieving stable proteins despite a highly biased amino acid content. Reported here are the synthesis and characterization of two disulfide-bridged mutants derived from the MB-1 designer protein. Both mutants outperformed their parent protein MB-1 with their bridge formed, as shown by circular dichroism, size exclusion chromatography, thermal denaturation, and proteolytic degradation experiments. When the disulfide bridges were cleaved, the mutants' behavior changed: the mutants significantly unfolded, suggesting that the introduction of Cys residues was deleterious to MB-1-folding. In an attempt to compensate for the mutations used, a Tyr62-Trp mutation was performed, leading to an increase in bulk and hydrophobicity in the core. The Trp-containing disulfide-bridged mutants did not behave as well as the original MB-1Trp, suggesting that position 62 might not be adequate for a compensatory mutation.

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

    CERN Document Server

    Ruan, Xinbo

    2014-01-01

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

  15. Bridging the Design-Science Gap with Tools: Science Learning and Design Behaviors in a Simulated Environment for Engineering Design

    Science.gov (United States)

    Chao, Jie; Xie, Charles; Nourian, Saeid; Chen, Guanhua; Bailey, Siobhan; Goldstein, Molly H.; Purzer, Senay; Adams, Robin S.; Tutwiler, M. Shane

    2017-01-01

    Many pedagogical innovations aim to integrate engineering design and science learning. However, students frequently show little attempt or have difficulties in connecting their design projects with the underlying science. Drawing upon the Cultural-Historical Activity Theory, we argue that the design tools available in a learning environment…

  16. Thermal behavior of IDOT integral abutment bridges and proposed design modifications.

    Science.gov (United States)

    2013-05-01

    The Illinois Department of Transportation (IDOT) has increasingly constructed integral abutment bridges (IABs) : over the past few decades, similar to those in many other states. Because the length and skew limitations : currently employed by IDOT ha...

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

    CERN Document Server

    Seffah, Ahmed

    2015-01-01

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

  18. Issues in Designing Tutors for Games of Incomplete Information: a Bridge Case Study

    Science.gov (United States)

    Kemp, Ray; McKenzie, Ben; Kemp, Elizabeth

    There are a number of commercial packages for playing the game of bridge, and even more papers on possible techniques for improving the quality of such systems. We examine some of the AI techniques that have proved successful for implementing bridge playing systems and discuss how they might be adapted for teaching the game. We pay particular attention to the issue of incomplete information and include some of our own research into the subject.

  19. A New Local Flap Nipple Reconstruction Technique Using Dermal Bridge and Preoperatively Designed Tattoo

    Science.gov (United States)

    Iwahira, Yoshiko

    2017-01-01

    Background: Nipple–areolar reconstruction is the final step in breast reconstruction. Reconstruction using local flaps and tattooing is useful in cases of bilateral reconstruction, a small nipple–areolar complex (NAC) as the donor site, and avoiding disturbance of the normal side and other body parts. However, this method can cause projection loss and color fading of the nipple. Moreover, the breast mound is reconstructed with an implant. Methods: We performed nipple–areolar reconstruction of 90 nipples using clover-designed flaps oriented at 120 degrees and tattooing after breast silicone implantation in 64 women. The tattoo was designed before flap operation and stained darker. Following donor site closure, a dermal flap was made as a bridge for nipple support. The nipple space was separated by the dermal flap from the breast mound and was filled with subcutaneous tissue. The size of the reconstructed nipple projection was measured postoperatively and 1 year later. The projection maintenance rate was calculated. Results: The heights of the nipple projection were 11.3 ± 1.8 mm (95% confidence interval [CI]: 10.9–11.7) just after the operation and 6.09 ± 2.4 mm (95% CI: 5.6–6.6) 1 year later. The actual range of nipple projection between these 2 heights was 5.2 ± 2.4 mm (95% CI: 4.7–5.7). The maintenance rate of the reconstructed nipple projection after 12 months was 54.1 ± 20.9 (95% CI: 49.7–58.5). The nipple color was maintained for over a year. Conclusions: Our nipple–areolar reconstruction technique could maintain the projection and color of the reconstructed nipple for a long period. Good outcomes were obtained in this implant-based breast reconstruction. PMID:28507843

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

    Science.gov (United States)

    Takeya, Kouichi; Sasaki, Eiichi; Kobayashi, Yusuke

    2016-01-01

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

  1. Experimental design for the evaluation of high-T(sub c) superconductive thermal bridges in a sensor satellite

    Science.gov (United States)

    Scott, Elaine P.; Lee, Kasey M.

    1994-01-01

    Infrared sensor satellites, which consist of cryogenic infrared sensor detectors, electrical instrumentation, and data acquisition systems, are used to monitor the conditions of the earth's upper atmosphere in order to evaluate its present and future changes. Currently, the electrical connections (instrumentation), which act as thermal bridges between the cryogenic infrared sensor and the significantly warmer data acquisition unit of the sensor satellite system, constitute a significant portion of the heat load on the cryogen. As a part of extending the mission life of the sensor satellite system, the researchers at the National Aeronautics and Space Administration's Langley Research Center (NASA-LaRC) are evaluating the effectiveness of replacing the currently used manganin wires with high-temperature superconductive (HTS) materials as the electrical connections (thermal bridges). In conjunction with the study being conducted at NASA-LaRC, the proposed research is to design a space experiment to determine the thermal savings on a cryogenic subsystem when manganin leads are replaced by HTS leads printed onto a substrate with a low thermal conductivity, and to determine the thermal conductivities of HTS materials. The experiment is designed to compare manganin wires with two different types of superconductors on substrates by determining the heat loss by the thermal bridges and providing temperature measurements for the estimation of thermal conductivity. A conductive mathematical model has been developed and used as a key tool in the design process and subsequent analysis.

  2. BRIDGING OUTDOOR AND INDOOR ENVIRONMENTAL SIMULATION FOR ASSESSING AND AIDING SUSTAINABLE URBAN NEIGHBOURHOOD DESIGN

    Directory of Open Access Journals (Sweden)

    Chengzhi Peng

    2012-11-01

    Full Text Available Urban dwellers in cities located in hot-arid or hothumid regions have greater needs to live in between outdoor and indoor environments. The sustainability of urban building design in these regions cannot be fully assessed by indoor environmental simulation not taking into account the microclimatic factors of the surrounding urban neighbourhood. We find that the current suites of outdoor and indoor simulation software do not connect with each other to give us a holistic understanding of both outdoor and indoor simulation results. This paper reports on our current development of a methodological framework for bridging the current gap between outdoor and indoor environmental simulation. Our objective is that assessment of sustainability at an urban neighbourhood level can be carried out more holistically, and hence achieving more valid environmental simulations from an urban  dwelling point of view. The outdoor-indoor coupling methodology is currently modelled on a digital work flow among three key software platforms: (1 ENVImet for urban neighbourhood outdoor simulation, (2 Ecotect for building indoor simulation, (3 uCampus for combined outdoor-indoor 3D visualisation modelling of an entire urban neighbourhood including its individual buildings. A case study of a new neighbourhood development proposed for New Cairo is presented to demonstrate how indoor environmental simulation can be grounded on outdoor environmental simulation of the urban neighbourhood. Graphical outputs from this outdoorindoor coupling approach to neighbourhood simulation can be further brought together onto a Web-based 3D virtual reality modelling platform to enable wider accessibility.

  3. Myocardial Bridge

    Science.gov (United States)

    ... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge En español Your heart is made of muscle, ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

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

    Directory of Open Access Journals (Sweden)

    Solazzi L.

    2010-06-01

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

  5. Analytical model and design of spoke-type permanent-magnet machines accounting for saturation and nonlinearity of magnetic bridges

    Science.gov (United States)

    Liang, Peixin; Chai, Feng; Bi, Yunlong; Pei, Yulong; Cheng, Shukang

    2016-11-01

    Based on subdomain model, this paper presents an analytical method for predicting the no-load magnetic field distribution, back-EMF and torque in general spoke-type motors with magnetic bridges. Taking into account the saturation and nonlinearity of magnetic material, the magnetic bridges are equivalent to fan-shaped saturation regions. For getting standard boundary conditions, a lumped parameter magnetic circuit model and iterative method are employed to calculate the permeability. The final field domain is divided into five types of simple subdomains. Based on the method of separation of variables, the analytical expression of each subdomain is derived. The analytical results of the magnetic field distribution, Back-EMF and torque are verified by finite element method, which confirms the validity of the proposed model for facilitating the motor design and optimization.

  6. Synthesis and evaluation of lightweight concrete research relevant to the AASHTO LRFD bridge design specifications : potential revisions for definition and mechanical properties.

    Science.gov (United States)

    2012-11-01

    Much of the fundamental basis for the current lightweight concrete provisions in the AASHTO LRFD Bridge : Design Specifications is based on research of lightweight concrete (LWC) from the 1960s. The LWC that was : part of this research used tradition...

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

    Directory of Open Access Journals (Sweden)

    Wenxue LIU

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

  8. Asset management business model for design, realization, and maintenance of fibre reinforced polymer bridges

    NARCIS (Netherlands)

    Sebastian, R.

    2013-01-01

    This paper particularly addresses the market implementation of Fibre Reinforced Polymer (FRP) for bridges. It presents the concept of demand and supply chain innovation as being investigated within two ongoing European collaborative research projects (FP7) titled Trans-IND and PANTURA. FRP has

  9. Design and Implementation of a New System for Large Bridge Monitoring—GeoSHM

    Directory of Open Access Journals (Sweden)

    Xiaolin Meng

    2018-03-01

    Full Text Available Structural Health Monitoring (SHM is a relatively new branch of civil engineering that focuses on assessing the health status of infrastructure, such as long-span bridges. Using a broad range of in-situ monitoring instruments, the purpose of the SHM is to help engineers understand the behaviour of structures, ensuring their structural integrity and the safety of the public. Under the Integrated Applications Promotion (IAP scheme of the European Space Agency (ESA, a feasibility study (FS project that used the Global Navigation Satellite Systems (GNSS and Earth Observation (EO for Structural Health Monitoring of Long-span Bridges (GeoSHM was initiated in 2013. The GeoSHM FS Project was led by University of Nottingham and the Forth Road Bridge (Scotland, UK, which is a 2.5 km long suspension bridge across the Firth of Forth connecting Edinburgh and the Northern part of Scotland, was selected as the test structure for the GeoSHM FS project. Initial results have shown the significant potential of the GNSS and EO technologies. With these successes, the FS project was further extended to the demonstration stage, which is called the GeoSHM Demo project where two other long-span bridges in China were included as test structures. Led by UbiPOS UK Ltd. (Nottingham, UK, a Nottingham Hi-tech company, this stage focuses on addressing limitations identified during the feasibility study and developing an innovative data strategy to process, store, and interpret monitoring data. This paper will present an overview of the motivation and challenges of the GeoSHM Demo Project, a description of the software and hardware architecture and a discussion of some primary results that were obtained in the last three years.

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

    Science.gov (United States)

    Sadeghi, H.

    2015-12-01

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

  11. Design and fabrication of single-crystal GaN nano-bridge on homogeneous substrate for nanoindentation

    Science.gov (United States)

    Hung, Shang-Chao

    2014-12-01

    This study reports a simple method to design and fabricate a freestanding GaN nano-bridge over a homogeneous short column as supporting leg. Test samples were fabricated from MOCVD-grown single-crystal GaN films over sapphire substrate using a FIB milling to leave freestanding short spans. We also investigated the nanoindentation characteristics and the corresponding nanoscopic mechanism of the GaN nano-bridge and its short column with a conical indenter inside transmission electron microscopy. The stress-strain mechanical properties and Young's modulus have also been examined and calculated as 108 GPa ± 4.8 % by the strain energy method. The significant slope switch of the L- D curve corresponds to the transition from the single-point bending indentation to the surface stretching indentation and has been interpreted with the evolution of TEM images. This freestanding fabrication and test have key advantages to characterize nanoscale behavior of one-dimensional bridge structure and greater ease of sample preparation over other micro-fabrication techniques.

  12. Design and construction of a cable-stayed composite girder bridge with precast RC-slabs; Purekyasuto shohan gosei keta shachokoyo no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, K. [Tokyo Metropolitan Univ. (Japan). Faculty of Technology; Shimura, T.; Tachibana, Y.; Echigo, S. [Kawada Industries Inc., Tokyo (Japan)

    1995-09-20

    A report on design and execution of cable-stayed composite girder bridge with precast RC-slabs constructed first in Japan though in small scale was described. This bridge adopted steel slabs relatively low in slab height for main slab and with two boxes slab section, and was designed at an aim of being more economic and shorter in its working term in comparison with steel girder slab type, on a base of the design in a region allowable with the existing design standards. This bridge is mainly in accordance with the regulation on continuous bridge in the prescription of road bridge, and is designed for normal RC-girder selecting between girder supports to direction normal to bridge axis as usual without using specially strong concrete to the girder. And, in order to fill with the regulation on allowable tensile stress on considering effects of creep and drying shrinkage, a method adding prestress to the slabs was adopted. Furthermore, a loop-like overlap joint for cable joint for the precast girders, expansion concrete for joint portion to compose the girder with the steel slab and so forth were adopted. 12 refs., 22 figs., 5 tabs.

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

    Directory of Open Access Journals (Sweden)

    Qiao You-Lin

    2011-05-01

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

  14. 47 CFR 80.331 - Bridge-to-bridge communication procedure.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge communication procedure. 80..., Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a) Vessels subject to the Bridge-to-Bridge Act transmitting on the designated navigational frequency must conduct...

  15. Assessment of vehicular live load and load factors for design of short-span bridges according to the new Egyptian Code

    Directory of Open Access Journals (Sweden)

    Hatem M. Seliem

    2015-04-01

    The study shows that concrete box-girders designed according to ECP-201:2012 and ECP-201:2003 using the ultimate limit state method yield almost the same demand. Despite the increase in the VLL of ECP-201:2012, and consequently the live load forces, concrete I-shaped girder bridges will be subjected to less total factored internal forces in comparison to ECP-201:2003 This is attributed to the interaction between the live to dead loads ratio and the load combinations. Design of composite steel plate girder bridges according to ECP-201:2012 using the allowable stress design method yields over designed sections.

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

    Science.gov (United States)

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

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

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...

  18. Railroad Bridges

    Data.gov (United States)

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

  19. Design, fabrication, erection of Yuge-Ohashi bridge; Yuge ohashi no sekkei seisaku kasetsu

    Energy Technology Data Exchange (ETDEWEB)

    Nagamine, T.; Konishi, T.; Sasaki, K.; Miyakawa, T. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1995-12-20

    Introduced herein is the construction of Yuge-Ohashi Bridge, a 325-meter long three-span cable-stayed structure. Each tower is provided with deflectors to prevent galloping vibration that the bridge may experience after completion. Because it was afraid that the towers during the erection process would experience at the base sections a bend that would be greater than their withstand strength, vibration dampers TMDs (Tuned Mass Dampers) were installed. To enable the spars to withstand strong wind after completion, wing-type flaps were arranged on their sides. To damp vibration during the spar cantilever erection process, TMDs of the cantilever type were provided capable of responding to the vertical direction vibration, for which weights were caused to travel along the arms for tuning. To prevent the top-stage cables from rain caused vibration, U-shape grooves were provided. To prevent the intermediate-stage cables from rain caused vibration, high-attenuation rubber dampers were installed. A side span spar and a tower were installed en bloc by FC (Floating Crane) boats, and the central span spar was installed by cantilever erection. Thanks to the fuzzy control-aided accuracy management system, cable adjustment was efficiently accomplished and the accuracy fell within the target value range. 4 refs., 5 figs.

  20. Comprehensive evaluation of fracture critical bridges.

    Science.gov (United States)

    2014-02-01

    Two-girder steel bridges are classified as fracture critical bridges based on the definition given in the AASHTO LRFD Bridge Design Specifications. In a fracture critical bridge a failure of a tension member leads to collapse of the bridge. However, ...

  1. An Optimization Algorithm for the Design of an Irregularly-Shaped Bridge Based on the Orthogonal Test and Analytic Hierarchy Process

    Directory of Open Access Journals (Sweden)

    Hanbing Liu

    2016-11-01

    Full Text Available Irregularly-shaped bridges are usually adopted to connect the main bridge and ramps in urban overpasses, which are under significant flexion-torsion coupling effects and in complicated stress states. In irregular-shaped bridge design, the parameters such as ramp radius, bifurcation diaphragm stiffness, box girder height, and supporting condition could affect structural performance in different manners. In this paper, the influence of various parameters on three indices, including maximum stress, the stress variation coefficient, and the fundamental frequency of torsional vibration, is investigated and analyzed based on orthogonal test method. Through orthogonal analysis, the major influence parameters and corresponding optimal values for these indices are achieved. Combining with the analytic hierarchy process (AHP, the hierarchical structure model of the multi-indices orthogonal test is established and a comprehensive weight analysis method is proposed to reflect the parameter influence on overall mechanical properties of an irregularly-shaped bridge. Influence order and optimal values of parameters for overall mechanical properties are determined based on the weight of factors and levels calculated by the comprehensive weight analysis method. The results indicate that the comprehensive weight analysis method is superior to the overall balance method, which verifies the effectiveness and accuracy of the comprehensive weight analysis in the parameter optimization of the multi-indices orthogonal test for an irregularly-shaped bridge. Optimal parameters obtained in this paper can provide reference and guidance for parameter control in irregularly-shaped bridge design.

  2. Life cycle assessment based environmental impact estimation model for pre-stressed concrete beam bridge in the early design phase

    International Nuclear Information System (INIS)

    Kim, Kyong Ju; Yun, Won Gun; Cho, Namho; Ha, Jikwang

    2017-01-01

    The late rise in global concern for environmental issues such as global warming and air pollution is accentuating the need for environmental assessments in the construction industry. Promptly evaluating the environmental loads of the various design alternatives during the early stages of a construction project and adopting the most environmentally sustainable candidate is therefore of large importance. Yet, research on the early evaluation of a construction project's environmental load in order to aid the decision making process is hitherto lacking. In light of this dilemma, this study proposes a model for estimating the environmental load by employing only the most basic information accessible during the early design phases of a project for the pre-stressed concrete (PSC) beam bridge, the most common bridge structure. Firstly, a life cycle assessment (LCA) was conducted on the data from 99 bridges by integrating the bills of quantities (BOQ) with a life cycle inventory (LCI) database. The processed data was then utilized to construct a case based reasoning (CBR) model for estimating the environmental load. The accuracy of the estimation model was then validated using five test cases; the model's mean absolute error rates (MAER) for the total environmental load was calculated as 7.09%. Such test results were shown to be superior compared to those obtained from a multiple-regression based model and a slab area base-unit analysis model. Henceforth application of this model during the early stages of a project is expected to highly complement environmentally friendly designs and construction by facilitating the swift evaluation of the environmental load from multiple standpoints. - Highlights: • This study is to develop the model of assessing the environmental impacts on LCA. • Bills of quantity from completed designs of PSC Beam were linked with the LCI DB. • Previous cases were used to estimate the environmental load of new case by CBR model. • CBR

  3. Life cycle assessment based environmental impact estimation model for pre-stressed concrete beam bridge in the early design phase

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyong Ju, E-mail: kjkim@cau.ac.kr; Yun, Won Gun, E-mail: ogun78@naver.com; Cho, Namho, E-mail: nhc51@cau.ac.kr; Ha, Jikwang, E-mail: wlrhkd29@gmail.com

    2017-05-15

    The late rise in global concern for environmental issues such as global warming and air pollution is accentuating the need for environmental assessments in the construction industry. Promptly evaluating the environmental loads of the various design alternatives during the early stages of a construction project and adopting the most environmentally sustainable candidate is therefore of large importance. Yet, research on the early evaluation of a construction project's environmental load in order to aid the decision making process is hitherto lacking. In light of this dilemma, this study proposes a model for estimating the environmental load by employing only the most basic information accessible during the early design phases of a project for the pre-stressed concrete (PSC) beam bridge, the most common bridge structure. Firstly, a life cycle assessment (LCA) was conducted on the data from 99 bridges by integrating the bills of quantities (BOQ) with a life cycle inventory (LCI) database. The processed data was then utilized to construct a case based reasoning (CBR) model for estimating the environmental load. The accuracy of the estimation model was then validated using five test cases; the model's mean absolute error rates (MAER) for the total environmental load was calculated as 7.09%. Such test results were shown to be superior compared to those obtained from a multiple-regression based model and a slab area base-unit analysis model. Henceforth application of this model during the early stages of a project is expected to highly complement environmentally friendly designs and construction by facilitating the swift evaluation of the environmental load from multiple standpoints. - Highlights: • This study is to develop the model of assessing the environmental impacts on LCA. • Bills of quantity from completed designs of PSC Beam were linked with the LCI DB. • Previous cases were used to estimate the environmental load of new case by CBR model. • CBR

  4. Sustainable Bridge Infrastructure Procurement

    DEFF Research Database (Denmark)

    Safi, Mohammed; Du, Guangli; Simonsson, Peter

    2016-01-01

    The lack of a flexible but systematic approach for integrating lifecycle aspects into bridge investment decisions is a major obstacle hindering the procurement of sustainable bridge infrastructures. This paper addresses this obstacle by introducing a holistic approach that agencies could use...... to procure the most “sustainable” (lifecycle-efficient) bridge through a fair design-build (D-B) tendering process, considering all the main aspects: life-cycle cost (LCC), service life-span, aesthetic demands and environmental impacts (LCA)....

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

    DEFF Research Database (Denmark)

    Andersen, Kristine

    2007-01-01

    Considering the rapidly growing amount of digital educational materials only few of them bridge the gab between experimental learning environments and computer based learning environments (Gardner, 1991). Observations from two cases in primary school and lower secondary school in the subject...... with a prototype of a MOO storyline. The aim of the MOO storyline is to challenge the potential of dialogue, user involvement, and learning responsibility and to use the children?s natural curiosity and motivation for game playing, especially when digital games involves other children. The paper proposes a model......, based on the narrative approach for experimental learning subjects, relying on ideas from Csikszentmihalyis notion of flow (Csikszentmihalyi, 1991), storyline-pedagogy (Meldgaard, 1994) and ideas from Howard Gardner (Gardner, 1991). The model forms the basis for educational games to be used in home...

  6. Analytical model and design of spoke-type permanent-magnet machines accounting for saturation and nonlinearity of magnetic bridges

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Peixin; Chai, Feng [State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001 (China); Department of Electrical Engineering, Harbin Institute of Technology, Harbin 150001 (China); Bi, Yunlong [Department of Electrical Engineering, Harbin Institute of Technology, Harbin 150001 (China); Pei, Yulong, E-mail: peiyulong1@163.com [Department of Electrical Engineering, Harbin Institute of Technology, Harbin 150001 (China); Cheng, Shukang [State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001 (China); Department of Electrical Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2016-11-01

    Based on subdomain model, this paper presents an analytical method for predicting the no-load magnetic field distribution, back-EMF and torque in general spoke-type motors with magnetic bridges. Taking into account the saturation and nonlinearity of magnetic material, the magnetic bridges are equivalent to fan-shaped saturation regions. For getting standard boundary conditions, a lumped parameter magnetic circuit model and iterative method are employed to calculate the permeability. The final field domain is divided into five types of simple subdomains. Based on the method of separation of variables, the analytical expression of each subdomain is derived. The analytical results of the magnetic field distribution, Back-EMF and torque are verified by finite element method, which confirms the validity of the proposed model for facilitating the motor design and optimization. - Highlights: • The no-load magnetic field of poke-type motors is firstly calculated by analytical method. • The magnetic circuit model and iterative method are employed to calculate the permeability. • The analytical expression of each subdomain is derived.. • The proposed method can effectively reduce the predesign stages duration.

  7. Analytical model and design of spoke-type permanent-magnet machines accounting for saturation and nonlinearity of magnetic bridges

    International Nuclear Information System (INIS)

    Liang, Peixin; Chai, Feng; Bi, Yunlong; Pei, Yulong; Cheng, Shukang

    2016-01-01

    Based on subdomain model, this paper presents an analytical method for predicting the no-load magnetic field distribution, back-EMF and torque in general spoke-type motors with magnetic bridges. Taking into account the saturation and nonlinearity of magnetic material, the magnetic bridges are equivalent to fan-shaped saturation regions. For getting standard boundary conditions, a lumped parameter magnetic circuit model and iterative method are employed to calculate the permeability. The final field domain is divided into five types of simple subdomains. Based on the method of separation of variables, the analytical expression of each subdomain is derived. The analytical results of the magnetic field distribution, Back-EMF and torque are verified by finite element method, which confirms the validity of the proposed model for facilitating the motor design and optimization. - Highlights: • The no-load magnetic field of poke-type motors is firstly calculated by analytical method. • The magnetic circuit model and iterative method are employed to calculate the permeability. • The analytical expression of each subdomain is derived.. • The proposed method can effectively reduce the predesign stages duration.

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

    International Nuclear Information System (INIS)

    Valot, Carole; Bertolus, Marjorie; Konings, Rudy; Somers, Joe; Groot, Sander de

    2010-01-01

    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

  9. Timber in Bridge Structures

    OpenAIRE

    Detkin, Viktoria

    2016-01-01

    The purpose of this final year project was to study the properties of timber as a structural material and the suitability of wood in load bearing members for bridge structures. For a case study, an existing timber bridge was selected. Due to its condition the bridge should be replaced. The design of a new bridge with steel beams holding a glulam deck was made. During the case study the replacement of steel beams by glulam timber ones was discussed. Some calculations were made in order to ...

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

    Science.gov (United States)

    2015-11-01

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

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

    Science.gov (United States)

    Hops, Jonathan

    1993-01-01

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

  12. Covered Bridge Security Manual

    Science.gov (United States)

    Brett Phares; Terry Wipf; Ryan Sievers; Travis Hosteng

    2013-01-01

    The design, construction, and use of covered timber bridges is all but a lost art in these days of pre-stressed concrete, high-performance steel, and the significant growth both in the volume and size of vehicles. Furthermore, many of the existing covered timber bridges are preserved only because of their status on the National Registry of Historic Places or the...

  13. Design of an improved RCD buffer circuit for full bridge circuit

    Science.gov (United States)

    Yang, Wenyan; Wei, Xueye; Du, Yongbo; Hu, Liang; Zhang, Liwei; Zhang, Ou

    2017-05-01

    In the full bridge inverter circuit, when the switch tube suddenly opened or closed, the inductor current changes rapidly. Due to the existence of parasitic inductance of the main circuit. Therefore, the surge voltage between drain and source of the switch tube can be generated, which will have an impact on the switch and the output voltage. In order to ab sorb the surge voltage. An improve RCD buffer circuit is proposed in the paper. The peak energy will be absorbed through the buffer capacitor of the circuit. The part energy feedback to the power supply, another part release through the resistor in the form of heat, and the circuit can absorb the voltage spikes. This paper analyzes the process of the improved RCD snubber circuit, According to the specific parameters of the main circuit, a reasonable formula for calculating the resistance capacitance is given. A simulation model will be modulated in Multisim, which compared the waveform of tube voltage and the output waveform of the circuit without snubber circuit with the improved RCD snubber circuit. By comparing and analyzing, it is proved that the improved buffer circuit can absorb surge voltage. Finally, experiments are demonstrated to validate that the correctness of the RC formula and the improved RCD snubber circuit.

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

    Science.gov (United States)

    Miaskiewicz, Tomasz

    2010-01-01

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

  15. Bridging the Gap between Actors and Digital tools in a Furnishing Design Process

    DEFF Research Database (Denmark)

    Rasmussen, Mai; Gade, Anne Nørkjær; Jensen, Rasmus Lund

    2017-01-01

    The high level of complexity in today’s building design requires a high level of interdisciplinary collaboration, which historically is an uncommon working method in the building industry. To support the interdisciplinary collaboration, new digital tools such as Building Information Models (BIM......) and Virtual Reality (VR) can be implemented in various phases of the building project. The implementation of BIM is expected to support the designers and improve the collaboration among multiple actors, but the social aspects related to the use of BIM in the design process needs further investigation...

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    This paper presents the design, modeling, and control of an isolated dc-dc three-port converter (TPC) based on an interleaved-boost full-bridge converter with pulsewidth modulation (PWM) and phase-shift control for hybrid renewable energy systems. In the proposed topology, the switches are driven...

  17. Practical cable tension adjustment based upon the satisfaction concept of bridge designers; Sekkeisha no manzokudo wo koryo shita fuzzy cable choryoku choseiho

    Energy Technology Data Exchange (ETDEWEB)

    Kaneyoshi, M.; Tanaka, H. [Hitachi Zosen, Tokyo (Japan)] Furuta, H. [Kansai Univ., Osaka (Japan)

    1998-07-21

    Cable tension adjustment of bridge beam of cable stayed bridge and so forth that uses cable as a structural element is classified into (1) pre-stress adjustment of cable at design level, (2) slim adjustment required at erection level. The former deals with the structurally high dimensional statically indeterminate structures like cable-stayed bridges and is a process for carrying out economical design by making the stress resultant of main girder small due to the introduction of appropriate pre-stress stress on this cable. The later is the process of getting rid off the errors caused in cable tension and camber of girder and tower regarding various errors such as design, fabrication and erection errors. The authors developed analysis method using fuzzy regression analysis and this has been applied in number of practical bridges. In this research, much more practical method is developed where the aspire of designer can be introduced easily by applying the satisfaction concept. By using this, pre-stress adjustment and shim adjustment of cable can be possible in a practical way. 9 refs., 7 figs., 8 tabs.

  18. Development of load and resistance factor design for FRP strengthening of reinforced concrete bridges.

    Science.gov (United States)

    2006-05-01

    Externally bonded fiber reinforced polymer (FRP) composites are an increasingly adopted technology for the renewal of existing concrete structures. In order to encourage the further use of these materials, a design code is needed that considers the i...

  19. Enterprise Command, Control, and Design: Bridging C2 Practice and CT Research

    National Research Council Canada - National Science Library

    Nissen, Mark E

    2007-01-01

    .... This is particularly the case with research in the area of Contingency Theory (CT). The central premise of CT is that no single enterprise design is ideal for all missions, environments, and contexts...

  20. Determination of minimum height and lateral design load for MASH test level 4 bridge rails.

    Science.gov (United States)

    2011-12-01

    The Manual for Assessing Safety Hardware (MASH) prescribes higher design vehicle impact speed and mass for test level 4 barriers compared to its predecessor National Cooperative Highway Research Program (NCHRP) Report 350. This has resulted in a 56 p...

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

    Directory of Open Access Journals (Sweden)

    Barbara Goličnik

    2005-01-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Mona Komeijani

    2016-03-01

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

  3. Design and Implementation of Battery Charger with Power Factor Correction Using Sepic Converter and Full-bridge DC-DC Converter

    OpenAIRE

    Efendi, Moh. Zaenal; Windarko, Novie Ayub; Amir, Moh. Faisal

    2013-01-01

    This paper presents a design and implementation of a converter which has a high power factor for battery charger application. The converter is a combination of a SEPIC converter and a full-bridge DC-DC converter connected in two stages of series circuit. The SEPIC converter works in discontinuous conduction mode and it serves as a power factor corrector so that the shape of input current waveform follows the shape of input voltage waveform. The full-bridge DC-DC converter serves as a regulato...

  4. Bridging Anticoagulation

    Science.gov (United States)

    ... clinical centers in the United States, Canada, and Brazil. A more detailed description of the study is ... Your Personal Message Send Message Share on Social Media Bridging Anticoagulation The BRIDGE Study Investigators Circulation. 2012; ...

  5. Development of wave and surge atlas for the design and protection of coastal bridges in south Louisiana : [tech summary].

    Science.gov (United States)

    2015-02-01

    The failures of highway bridges on the Gulf Coast seen in the aftermath of Hurricane Katrina in 2005 were unprecedented. : In the past four decades, wind waves accompanied by high surges from hurricanes have damaged a number of coastal : bridges alon...

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

    CERN Document Server

    Guenther, Milan

    2012-01-01

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

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

    Science.gov (United States)

    Fleming, Debra L.

    2008-01-01

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

  8. Bridging Professional Teacher Knowledge for Science and Literary Integration via Design-Based Research

    Science.gov (United States)

    Fazio, Xavier; Gallagher, Tiffany L.

    2018-01-01

    We offer insights for using design-based research (DBR) as a model for constructing professional development that supports curriculum and instructional knowledge regarding science and literacy integration. We spotlight experiences in the DBR process from data collected from a sample of four elementary teachers. Findings from interviews, focus…

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

    NARCIS (Netherlands)

    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

  10. A Design Quality Learning Unit in OO Modeling Bridging the Engineer and the Artist

    Science.gov (United States)

    Waguespack, Leslie J.

    2015-01-01

    Recent IS curriculum guidelines compress software development pedagogy into smaller and smaller pockets of course syllabi. Where undergraduate IS students once may have practiced modeling in analysis, design, and implementation across six or more courses in a curriculum using a variety of languages and tools they commonly now experience modeling…

  11. Bridging design and behavioral research with variance-based structural equation modeling

    NARCIS (Netherlands)

    Henseler, Jörg

    2017-01-01

    Advertising research is a scientific discipline that studies artifacts (e.g., various forms of marketing communication) as well as natural phenomena (e.g., consumer behavior). Empirical advertising research therefore requires methods that can model design constructs as well as behavioral constructs,

  12. Cybersecurity Protection: Design Science Research toward an Intercloud Transparent Bridge Architecture (ITCOBRA)

    Science.gov (United States)

    Wilson, Joe M.

    2013-01-01

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

  13. Effects of Thinking Style on Design Strategies: Using Bridge Construction Simulation Programs

    Science.gov (United States)

    Sun, Chuen-Tsai; Wang, Dai-Yi; Chang, Yu-Yeh

    2013-01-01

    Computer simulation users can freely control operational factors and simulation results, repeat processes, make changes, and learn from simulation environment feedback. The focus of this paper is on simulation-based design tools and their effects on student learning processes in a group of 101 Taiwanese senior high school students. Participants…

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

    DEFF Research Database (Denmark)

    Brynskov, Martin

    2007-01-01

    This paper will focus on the challenges in designing pervasive computing technology for children’s play, taking into account current trends in popular culture. In search of theoretical support for this work I have been exploring an activity-based approach called ‘habitats’ to describe the conditi......, informational, and pragmatic – together with the ability to describe their relations are a useful platform for practitioners and theorists who are forced to span a heterogeneous mash-up of technologies, theories, and professions.......This paper will focus on the challenges in designing pervasive computing technology for children’s play, taking into account current trends in popular culture. In search of theoretical support for this work I have been exploring an activity-based approach called ‘habitats’ to describe...

  15. Bridging Theory and Practice: Developing Guidelines to Facilitate the Design of Computer-based Learning Environments

    Directory of Open Access Journals (Sweden)

    Lisa D. Young

    2003-10-01

    Full Text Available Abstract. The design of computer-based learning environments has undergone a paradigm shift; moving students away from instruction that was considered to promote technical rationality grounded in objectivism, to the application of computers to create cognitive tools utilized in constructivist environments. The goal of the resulting computer-based learning environment design principles is to have students learn with technology, rather than from technology. This paper reviews the general constructivist theory that has guided the development of these environments, and offers suggestions for the adaptation of modest, generic guidelines, not mandated principles, that can be flexibly applied and allow for the expression of true constructivist ideals in online learning environments.

  16. Existing Steel Railway Bridges Evaluation

    Science.gov (United States)

    Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

    2016-12-01

    The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  17. Existing Steel Railway Bridges Evaluation

    Directory of Open Access Journals (Sweden)

    Vičan Josef

    2016-12-01

    Full Text Available The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  18. Design and construction of the Daini-Chikumagawa bridge; Dai ni Chikumagawa kyoryo no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Inaba, N.; Takasusuki, K.; Hirasawa, T.; Kanamori, M.

    1996-01-30

    The Daini-Chikumagawa bridge, having spans of 134m {times} 2 which is the largest in Japan as the concrete railroad, is a prestressed concrete (PC) oblique cable-stayed bridge building on the Hokuriku Shinkansen express line which is constructing towards Nagano Olympic (Feb.1998). Regarding adoption of the oblique cable-stayed bridge for the railroad bridge, there are very few examples on a global scale and in Japan besides this bridge there is only one example (Omoto bridge (Iwate pref.), span = 85m). One H type tower (H = 65m from the surface of bridge) is erected at the center of the Chikuma river and then main girders are built at the front and rear of this tower. These main girders, being separated into 5m {times} 24 blocks per one side excepting surroundings of the tower, are fabricated as a three room box type PC block (total width 12.8m; height 3.0m) each on the river beach near the spot. These blocks are jointed from the tower side by the overhanging work using the constructing vehicles and are fixed with oblique materials (cables; two face hanging system) at intervals of 10m. 4 refs., 16 figs., 5 tabs.

  19. Bridging the conservation design and delivery gap for wetland bird habitat maintenance and restoration in the Midwestern United States

    Science.gov (United States)

    Thogmartin, W.E.; Potter, B.; Soulliere, G.

    2011-01-01

    The U.S. Fish and Wildlife Service's adoption of Strategic Habitat Conservation is intended to increase the effectiveness and efficiency of conservation delivery by targeting effort in areas where biological benefits are greatest. Conservation funding has not often been allocated in accordance with explicit biological endpoints, and the gap between conservation design (the identification of conservation priority areas) and delivery needs to be bridged to better meet conservation goals for multiple species and landscapes. We introduce a regional prioritization scheme for North American Wetlands Conservation Act funding which explicitly addresses Midwest regional goals for wetland-dependent birds. We developed decision-support maps to guide conservation of breeding and non-breeding wetland bird habitat. This exercise suggested ~55% of the Midwest consists of potential wetland bird habitat, and areas suited for maintenance (protection) were distinguished from those most suited to restoration. Areas with greater maintenance focus were identified for central Minnesota, southeastern Wisconsin, the Upper Mississippi and Illinois rivers, and the shore of western Lake Erie and Saginaw Bay. The shores of Lakes Michigan and Superior accommodated fewer waterbird species overall, but were also important for wetland bird habitat maintenance. Abundant areas suited for wetland restoration occurred in agricultural regions of central Illinois, western Iowa, and northern Indiana and Ohio. Use of this prioritization scheme can increase effectiveness, efficiency, transparency, and credibility to land and water conservation efforts for wetland birds in the Midwestern United States.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    .g., disregarding shape anisotropy effects, and also incorporates some approximations. To validate the results, modelled data was compared to measurements on actual PHEBs and was found to predict the measured values within 13% for the investigated geometries. Subsequently, the model was used to establish a design...... that PHEBs can be applicable to several different areas within science including satellite attitude determination and magnetic bead detection in lab-on-a-chip applications, where detectivities down towards 1 nT Hz -0.5 at 1 Hz are required, and maybe even magnetic field measurements in scientific space......The applicability of miniaturized magnetic field sensors is being explored in several areas of magnetic field detection due to their integratability, low mass, and potentially low cost. In this respect, different thin-film technologies, especially those employing magnetoresistance, show great...

  1. Integral Abutment and Jointless Bridges

    Directory of Open Access Journals (Sweden)

    Cristian-Claudiu Comisu

    2005-01-01

    Full Text Available 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 that have their superstructure cast integrally with their substructure. The jointless bridges cost less to construct and require less maintenance then equivalent bridges with expansion joints. Integral bridges present a challenge for load distribution calculations because the bridge deck, piers, abutments, embankments and soil must all be considered as single compliant system. This paper presents some of the important features of integral abutment and jointless bridge design and some guidelines to achieve improved design. The goal of this paper is to enhance the awareness among the engineering community to use integral abutment and jointless bridges in Romania.

  2. 47 CFR 80.309 - Watch required by the Bridge-to-Bridge Act.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Watch required by the Bridge-to-Bridge Act. 80... Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch requirement contained in § 80.148, all vessels subject to the Bridge-to-Bridge Act must keep a watch on the designated...

  3. Conceptual design for the thermal shield bridges and multilayer insulation in the interconnect region for the SSC

    International Nuclear Information System (INIS)

    Baritchi, D.; Nicol, T.; Boroski, W.

    1991-01-01

    The interconnect region serves as the connection area between magnets. In order to minimize radiant heat transfer in the interconnect area, the authors used shield bridges which span the 80K and 20K shield gap between adjacent magnets. A sliding joint between bridge sections on adjacent magnets accommodates contraction during cool-down. An investigation was done to determine which attachment schemes (riveted or bolted versus welded) are better for heat transfer. Each shield bridge is covered with the same multilayer insulation scheme used throughout the body of the magnet. These shield bridges also contain pressure reliefs for each shield in the event of an internal piping failure. The reliefs are located in the upper half of the shield section in order to prevent liquid spills from impinging directly onto the vacuum vessel wall

  4. Design and operation of a transistorised bridge-type detector for burn-out in boiling heat transfer experiments

    Energy Technology Data Exchange (ETDEWEB)

    Salt, K J; Wintle, C A [Reactor Development Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1964-04-15

    Theoretical, technical and operational details of an instrument to protect heater rods in heat transfer burn-out experiments from actual rupture under electrical heating, by a Wheatstone bridge method. (author)

  5. Design and operation of a transistorised bridge-type detector for burn-out in boiling heat transfer experiments

    International Nuclear Information System (INIS)

    Salt, K.J.; Wintle, C.A.

    1964-04-01

    Theoretical, technical and operational details of an instrument to protect heater rods in heat transfer burn-out experiments from actual rupture under electrical heating, by a Wheatstone bridge method. (author)

  6. Comparison of using different bridge prosthetic designs for partial defect restoration through mathematical modeling.

    Science.gov (United States)

    Styranivska, Oksana; Kliuchkovska, Nataliia; Mykyyevych, Nataliya

    2017-01-01

    To analyze the stress-strain states of bone and abutment teeth during the use of different prosthetic designs of fixed partial dentures with the use of relevant mathematical modeling principles. The use of Comsol Multiphysics 3.5 (Comsol AB, Sweden) software during the mathematical modeling of stress-strain states provided numerical data for analytical interpretation in three different clinical scenarios with fixed dentures and different abutment teeth and demountable prosthetic denture with the saddle-shaped intermediate part. Microsoft Excel Software (Microsoft Office 2017) helped to evaluate absolute mistakes of stress and strain parameters of each abutment tooth during three modeled scenarios and normal condition and to summarize data into the forms of tables. In comparison with the fixed prosthetic denture supported by the canine, first premolar, and third molar, stresses at the same abutment teeth with the use of demountable denture with the saddle-shaped intermediate part decreased: at the mesial abutment tooth by 2.8 times, at distal crown by 6.1 times, and at the intermediate part by 11.1 times, respectively, the deformation level decreased by 3.1, 1.9, and 1.4 times at each area. The methods of mathematical modeling proved that complications during the use of fixed partial dentures based on the overload effect of the abutment teeth and caused by the deformation process inside the intermediate section of prosthetic construction.

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

    Science.gov (United States)

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

    2015-04-01

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

  8. Bridge Aesthetics and Structural Honesty

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    In bridges the overall form must be chosen with due respect to the transmission of forces if efficient structures shall be created, The design must therefore be governed by experienced structural engineers - in some cases assisted by aesthetic advisers on specific issues. Some basic requirements...... decisive for choosing the form of trusses, arches and cable-stayed bridges are outlined, and several examples show bridges designed without giving priority to the structural aspects....

  9. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

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

  10. Development of Inspection Robots for Bridge Cables

    Directory of Open Access Journals (Sweden)

    Hae-Bum Yun

    2013-01-01

    Full Text Available This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

  11. Development of inspection robots for bridge cables.

    Science.gov (United States)

    Yun, Hae-Bum; Kim, Se-Hoon; Wu, Liuliu; Lee, Jong-Jae

    2013-01-01

    This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

  12. Steel-soil composite bridge

    DEFF Research Database (Denmark)

    Du, Guangli; Pettersson, Lars; Karoumi, Raid

    2017-01-01

    viability, while their environmental performance is overlooked. Today’s designers are urged to seek new design options to reduce the environmental burdens. Sweden owns more than 24574 bridges and most of them are short spans. Among them, the slab frame bridge (CFB) is a common solution. Soil steel composite...... bridge (SSCB), alternatively, is a functionally equivalent solution to CFB and shows advantages in low cost and easy construction. This paper compares the environmental performance between these two bridge types based on life cycle assessment (LCA). The analysis and result shows that, the SSCB...

  13. Long-term behavior of integral abutment bridges : [technical summary].

    Science.gov (United States)

    2011-01-01

    Integral abutment bridges, a type of jointless bridge, are the construction option of choice when designing highway bridges in many parts of the country. Rather than providing an expansion joint to separate the substructure from the superstructure to...

  14. Design and Implementation of Battery Charger with Power Factor Correction using Sepic Converter and Full-bridge DC-DC Converter

    Directory of Open Access Journals (Sweden)

    Moh. Zaenal Efendi

    2013-12-01

    Full Text Available This paper presents a design and implementation of a converter which has a high power factor for battery charger application. The converter is a combination of a SEPIC converter and a full-bridge DC-DC converter connected in two stages of series circuit. The SEPIC converter works in discontinuous conduction mode and it serves as a power factor corrector so that the shape of input current waveform follows the shape of input voltage waveform. The full-bridge DC-DC converter serves as a regulator of output voltage and operates at continuous conduction mode. The experimental results show that the power factor of this converter system can be achieved up to 0.96.

  15. Building a Straw Bridge

    Science.gov (United States)

    Teaching Science, 2015

    2015-01-01

    This project is for a team of students (groups of two or three are ideal) to design and construct a model of a single-span bridge, using plastic drinking straws as the building material. All steps of the design, construction, testing and critiquing stages should be recorded by students in a journal. Students may like to include labelled diagrams,…

  16. Optimum design of large span concrete filled steel tubular arch bridge based on static, stability and modal analysis

    Institute of Scientific and Technical Information of China (English)

    赵长军; 胡隽; 徐兴

    2002-01-01

    A three-dimensional finite element model was established for a large span concrete filled steel tubular (CFST) arch bridge which is currently under construction. The arch rib, the spandrel columns, the prestressed concrete box-beam, the cast-in-situ concrete plate of bridge deck, the steel box-beam and the crossbeams connecting the two pieces of arch ribs, were modeled by three-dimensional Timoshenko beam elements (3DTBE). The suspenders were modeled by three-dimensional cable elements (3DCE). Both geometric nonlinearity and prestress effect could be included in each kind of element. At the same time a second finite element model with the same geometric and material properties excepted for the sectional dimension of arch rib was set up. Static dynamic analyses were performed to determine the corresponding characteristics of the structure. The results showed that the arch rib's axial rigidity could be determined by static analysis. The stability and vibration of this system could be separated into in-plane modes, out-of-plane modes and coupled modes. The in-plane stability and dynamic characteristics are determined by the arch rib's vertical stiffness and that of out-of-plane is determined by the crossbeams' stiffness and arch rib's lateral stiffness mainly. The in-plane stiffness is much greater than that of out-of-plane for this kind of bridge . The effect of geometric nonlinearity and prestress effect on bridge behavior is insignificant.

  17. Design and introduction of a disulfide bridge in firefly luciferase: increase of thermostability and decrease of pH sensitivity.

    Science.gov (United States)

    Imani, Mehdi; Hosseinkhani, Saman; Ahmadian, Shahin; Nazari, Mahboobeh

    2010-08-01

    The thermal sensitivity and pH-sensitive spectral properties of firefly luciferase have hampered its application in a variety of fields. It is proposed that the stability of a protein can be increased by introduction of disulfide bridge that decreases the configurational entropy of unfolding. A disulfide bridge is introduced into Photinus pyralis firefly luciferase to make two separate mutant enzymes with a single bridge. Even though the A103C/S121C mutant showed remarkable thermal stability, its specific activity decreased, whereas the A296C/A326C mutant showed tremendous thermal stability, relative pH insensitivity and 7.3-fold increase of specific activity. Moreover, the bioluminescence emission spectrum of A296C/A326C was resistant against higher temperatures (37 degrees C). Far-UV CD analysis showed slight secondary structure changes for both mutants. Thermal denaturation analysis showed that conformational stabilities of A103C/S121C and A296C/A326C are more than native firefly luciferase. It is proposed that since A296 and A326 are situated in the vicinity of the enzyme active site microenvironment in comparison with A103 and S121, the formation of a disulfide bridge in this region has more impact on enzyme kinetic characteristics.

  18. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

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

  19. Nondestructive testing for bridge diagnosis

    International Nuclear Information System (INIS)

    Oshima, Toshiyuki; Mikami, Shuichi; Yamazaki, Tomoyuki

    1997-01-01

    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.

  20. Fatigue test on aluminium bridges

    NARCIS (Netherlands)

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

    2005-01-01

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

  1. Vulnerability of bridges to fire

    DEFF Research Database (Denmark)

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

    2012-01-01

    Even if recent effort in developing methodology and measures for design structures against fire and explosions has been mostly focused on buildings, bridges can also be very sensitive to those actions, as witnesses by some recent bridge accidents, which caused major economic losses and also endan...

  2. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

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

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    Energy production from renewable energy sources is continuously varying, for this reason energy storage is becoming more and more important as the percentage of green energy increases. Newly developed fuel cells can operate in reverse mode as electrolyzer cells; therefore, they are becoming...... current. Dc-dc converter efficiency plays a fundamental role in the overall system efficiency since processed energy is always flowing through the converter; for this reason, loss analysis and optimization are a key component of the converter design. The paper presents an isolated full bridge boost dc...

  4. Bridging the Gap?

    Science.gov (United States)

    Salter, Colin

    2009-01-01

    The political context of the conversion of the Historic Tramway Bridge, adjacent to Sandon Point in Bulli (NSW, Australia), and how this was exploited to serve predetermined ends, illustrates that technologies can be designed to have particular social (and political) effects. Through reflection on this relatively small engineering project, this…

  5. Strategies For The Replacement Of Historic Bridge Guardrails

    OpenAIRE

    Clauss, Adam J.

    2014-01-01

    Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

  6. Hydrodynamic forces on inundated bridge decks

    Science.gov (United States)

    2009-05-01

    The hydrodynamic forces experienced by an inundated bridge deck have great importance in the design of bridges. Specifically, the drag force, lift force, and the moment acting on the bridge deck under various levels of inundation and a range of flow ...

  7. Final Environmental Assessment, Horse Creek Bridge Replacement

    Science.gov (United States)

    2010-10-01

    existing bridge pipes that have failed and replace the failed structure with a new, prefabricated pedestrian bridge within the original bridge footprint...vehicles, nor designed for support of standard passenger vehicle loads. The bridge would be a single prefabricated unit consisting of a steel grate...placed on new concrete abutments built on the existing foundations on the creek banks, and put in place by a crane operating from the vehicle parking

  8. Istanbul Bridge Conference 2014

    CERN Document Server

    Gülkan, Polat; Mahmoud, Khaled

    2016-01-01

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

  9. Bridged graphite oxide materials

    Science.gov (United States)

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

    2010-01-01

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

  10. Visual Storyboarding Provides a Conceptual Bridge from Research to Development: Students Can Imagine the Results of Their Decision Making, and Their Prioritization of the Many Facets of the Design Problem Will Facilitate the Development of a Strong Final Solution

    Science.gov (United States)

    Reeder, Kevin

    2005-01-01

    In order to facilitate the selection/prioritization process and bridge the gap of design research to design conceptualization, students need to visualize the big picture that describes how the research categories such as "user," "marketing," "functional/mechanical research" are related. This is achieved through the use of a visual storyboard. The…

  11. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...... in the Media”, “Audience Interactivity and Participation”, “The Role of Media and ICT Use for Evolving Social Relationships” and “Audience Transformations and Social Integration”. Building Bridges is the result of an ongoing dialogue between the Action and non-academic stakeholders in the field of audience......, Brian O’Neill, Andra Siibak, Sascha Trültzsch-Wijnen, Nicoletta Vittadini, Igor Vobič and Frauke Zeller. Stakeholder feedback from: Michelle Arlotta (DeAgostini), Andreea M. Costache (Association of Consumers of Audiovisual Media in Catalonia/TAC), Francesco Diasio (AMARC Europe), Marius Dragomir (Open...

  12. Mathematical bridges

    CERN Document Server

    Andreescu, Titu; Tetiva, Marian

    2017-01-01

    Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

  13. Shear capacity of in service prestressed concrete bridge girders.

    Science.gov (United States)

    2010-05-17

    The design of prestressed concrete bridge girders has changed significantly over the past several : decades. Specifically, the design procedure to calculate the shear capacity of bridge girders that : was used forty years ago is very different than t...

  14. A perspective on bridging scales and design of models using low-dimensional manifolds and data-driven model inference

    KAUST Repository

    Tegner, Jesper; Zenil, Hector; Kiani, Narsis A.; Ball, Gordon; Gomez-Cabrero, David

    2016-01-01

    Systems in nature capable of collective behaviour are nonlinear, operating across several scales. Yet our ability to account for their collective dynamics differs in physics, chemistry and biology. Here, we briefly review the similarities and differences between mathematical modelling of adaptive living systems versus physico-chemical systems. We find that physics-based chemistry modelling and computational neuroscience have a shared interest in developing techniques for model reductions aiming at the identification of a reduced subsystem or slow manifold, capturing the effective dynamics. By contrast, as relations and kinetics between biological molecules are less characterized, current quantitative analysis under the umbrella of bioinformatics focuses on signal extraction, correlation, regression and machine-learning analysis. We argue that model reduction analysis and the ensuing identification of manifolds bridges physics and biology. Furthermore, modelling living systems presents deep challenges as how to reconcile rich molecular data with inherent modelling uncertainties (formalism, variables selection and model parameters). We anticipate a new generative data-driven modelling paradigm constrained by identified governing principles extracted from low-dimensional manifold analysis. The rise of a new generation of models will ultimately connect biology to quantitative mechanistic descriptions, thereby setting the stage for investigating the character of the model language and principles driving living systems.

  15. A perspective on bridging scales and design of models using low-dimensional manifolds and data-driven model inference

    KAUST Repository

    Tegner, Jesper

    2016-10-04

    Systems in nature capable of collective behaviour are nonlinear, operating across several scales. Yet our ability to account for their collective dynamics differs in physics, chemistry and biology. Here, we briefly review the similarities and differences between mathematical modelling of adaptive living systems versus physico-chemical systems. We find that physics-based chemistry modelling and computational neuroscience have a shared interest in developing techniques for model reductions aiming at the identification of a reduced subsystem or slow manifold, capturing the effective dynamics. By contrast, as relations and kinetics between biological molecules are less characterized, current quantitative analysis under the umbrella of bioinformatics focuses on signal extraction, correlation, regression and machine-learning analysis. We argue that model reduction analysis and the ensuing identification of manifolds bridges physics and biology. Furthermore, modelling living systems presents deep challenges as how to reconcile rich molecular data with inherent modelling uncertainties (formalism, variables selection and model parameters). We anticipate a new generative data-driven modelling paradigm constrained by identified governing principles extracted from low-dimensional manifold analysis. The rise of a new generation of models will ultimately connect biology to quantitative mechanistic descriptions, thereby setting the stage for investigating the character of the model language and principles driving living systems.

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

    International Nuclear Information System (INIS)

    Xu, Fengyu; Wang, Xingsong; Wu, Hongtao

    2012-01-01

    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

  17. Hierarchical analysis of bridge decision makers : the role of new technology adoption in the timber bridge market : special project fiscal year 1992

    Science.gov (United States)

    1995-08-01

    Bridge design engineers and local highway officials make bridge replacement decisions across the : United States. The Analytical Hierarchy Process was used to characterize the bridge material selection : decision of these individuals. State Departmen...

  18. The Wien Bridge Oscillator Family

    DEFF Research Database (Denmark)

    Lindberg, Erik

    2006-01-01

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

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

    DEFF Research Database (Denmark)

    Makda, Ishtiyaq Ahmed; Nymand, M.

    2013-01-01

    for such application, it calls for a carefully optimized EMI filter which is designed and implemented in this work. Moreover, the negative input impedance of the regulated converter is extremely low; well-designed filter damping branch is also included. Differential mode noise is analyzed analytically for a 3KW/400V...

  20. Design and Comparison of Cascaded H-Bridge, Modular Multilevel Converter, and 5-L Active Neutral Point Clamped Topologies for Motor Drive Applications

    Energy Technology Data Exchange (ETDEWEB)

    Marzoughi, Alinaghi [Virginia Tech, Blacksburg, VA (United States). Center for Power Electronics Systems; Burgos, Rolando [Virginia Tech, Blacksburg, VA (United States). Bradley Dept. of Electrical and Computer Engineering; Boroyevich, Dushan [Virginia Tech, Blacksburg, VA (United States). Bradley Dept. of Electrical and Computer Engineering; Xue, Yaosuo [Siemens Corporate Research, Princeton, NJ (United States). Power Electronics Dept.

    2018-03-01

    This paper presents the design procedure and comparison of converters currently used in medium-voltage high-power motor drive applications. For this purpose, the cascaded H-bridge (CHB), modular multilevel converter (MMC), and five-level active neutral point clamped (5-L ANPC) topologies are targeted. The design is performed using 1.7-kV insulated gate bipolar transistors (IGBTs) for CHB and MMC converters, and utilizing 3.3- and 4.5-kV IGBTs for 5-L ANPC topology as normally done in industry. The comparison is done between the designed converter topologies at three different voltage levels (4.16, 6.9, and 13.8 kV, with only the first two voltage levels in case of the 5-L ANPC) and two different power levels (3 and 5 MVA), in order to elucidate the dependence of different parameters on voltage and power rating. Finally, the comparison is done from several points of view such as efficiency, capacitive energy storage, semiconductor utilization, parts count (for measure of reliability), and power density.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    This paper presents a low-cost bidirectional isolated dc–dc converte, derived from dual-active-bridge converter for the power sources with variable output voltage like supercapacitors. The proposed converter consists of push-pull-forward circuit half-bridge circuit (PPFHB) and a high-frequency tr......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...

  2. Bridge resource program.

    Science.gov (United States)

    2013-09-01

    The mission of Rutgers Universitys Center for Advanced Infrastructure and Transportation (CAIT) Bridge Resource Program (BRP) is to provide bridge engineering support to the New Jersey Department of Transportation (NJDOT)s Bridge Engineering an...

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

    Directory of Open Access Journals (Sweden)

    Mohamad Kassema

    2015-11-01

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

  4. NHDOT : process for municipally-managed state bridge aid program projects

    Science.gov (United States)

    2007-09-12

    The document sets for the requirements for a municipality which to manage the design and construction of a bridge rehabilitation or replacement project and receive Bridge Aid under the applicable provisions of RSA 234. Bridge Aid provided to a Munici...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-06-01

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

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

    Science.gov (United States)

    Roehl, Amy

    2013-01-01

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

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

    Science.gov (United States)

    Dolmans, Diana H J M; Tigelaar, D

    2012-01-01

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

  8. Chapter three Bridging the gaps between design and use: Developing tools to support environmental management and policy

    NARCIS (Netherlands)

    McIntosh, B.S.; Giupponi, C.; Voinov, A.A.; Smith, C.; Matthews, K.B.; Monticino, M.; Kolkman, M.J.; Crossman, N.; Ittersum, van M.K.; Haase, D.; Haase, A.; Mysiak, J.; Groot, J.C.J.; Sieber, S.; Verweij, P.; Quinn, N.; Waeger, P.; Gaber, N.; Hepting, D.; Scholten, H.; Sulis, A.; Delden, van H.; Gaddis, E.; Assaf, H.

    2008-01-01

    Integrated assessment models, decision support systems (DSS) and Geographic Information Systems (GIS) are examples of a growing number of computer-based tools designed to provide decision and information support to people engaged in formulating and implementing environmental policy and management.

  9. Seismic Performance of Multi-Span RC Railway Bridges

    DEFF Research Database (Denmark)

    Georgakis, Christos; Barrau, Xavier

    2008-01-01

    Presently, there is no clear method for determining the optimal railway bridge design for a particular ground type and expected seismic intensity. Four main types of RC bridge dominate the current multi-span railway bridge design trends – the Simply Supported Beam, Continuous Box-Girder (CBG), CBG...

  10. Post-Earthquake Traffic Capacity of Modern Bridges in California

    Science.gov (United States)

    2010-03-01

    Evaluation of the capacity of a bridge to carry self-weight and traffic loads after an earthquake is essential for a : safe and timely re-opening of the bridge. In California, modern highway bridges designed using the Caltrans : Seismic Design Criter...

  11. Repair, strengthening and upgrading of steel bridges in The Netherlands

    NARCIS (Netherlands)

    Snijder, H.H.; Hesselink, B.H.

    2018-01-01

    After World War II, many steel bridges were designed and built in The Netherlands. Many of these bridges are now of a substantial age and were designed for static and fatigue loading less severe than eventually present during their lifetime. Many of these bridges now show (fatigue) damage. Depending

  12. Remarks on crack-bridging concepts

    International Nuclear Information System (INIS)

    Bao, G.; Suo, Z.

    1992-01-01

    The article draws upon recent work by us and our colleagues on metal and ceramic matrix composites for high temperature engines. The central theme here is to deduce mechanical properties, such as toughness, strength and notch-ductility, from bridging laws that characterize inelastic processes associated with fracture. A particular set of normalization is introduced to present the design charts, segregating the roles played by the shape, and the scale, of a bridging law. A single material length, γ 0 E/σ 0 , emerges, where γ 0 is the limiting-separation, σ 0 the bridging-strength, and E the Young's modulus of the solid. It is the huge variation of this length-from a few manometers for atomic bond, to a meter for cross-over fibers - that underlies the richness in material behaviors. Under small-scale bridging conditions, γ 0 E/σ 0 is the only basic length scale in the mechanics problem and represents, with a pre-factor about 0.4, the bridging zone size. A catalog of small-scale bridging solutions is compiled for idealized bridging laws. Large-scale bridging introduces a dimensionless group, a/(γ 0 E/σ 0 ), where a is a length characterizing the component. The group plays a major role in all phenomena associated with bridging, and provides a focus of discussion in this article. For example, it quantifies the bridging scale when a is the unbridged crack length, and notch-sensitivity when a is hole radius. The difference and the connection between Irwin's fracture mechanics and crack bridging concepts are discussed. It is demonstrated that fracture toughness and resistance curve are meaningful only when small-scale bridging conditions prevail, and therefore of limited use in design with composites. Many other mechanical properties of composites, such as strength and notch-sensitivity, can be simulated by invoking large-scale bridging concepts. 37 refs., 21 figs., 3 tabs

  13. Design and construction of PC cable-stayed bridge reducing the weight of dead load (Minamitabaru No. 1 Bridge). Shuko danmen no keiryoka wo hakatta PC shachokyo (kasho Minamitabaru 1 go kyo)

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, H. (Building Research Inst., Tokyo (Japan)); Ikari, K.; Ono, Y. (Ministry of Construction, Tokyo (Japan)); Hirano, A.

    1993-03-15

    The Minamitabaru No.1 bridge is a PC cable-stayed bridge with a 170m center span. The cross section dead load weight of the main beam in the center span is reduced to decrease the unbalance moment during construction and the negative reaction force after the completion. As a result, the average volume of concrete in the center span becomes 0.55m[sup 3]/m[sup 2] which is less by about 20% in comparison with a PC cable-stayed bridge of the similar scale. Separated 2 chamber box girder cross section is adopted for the shape of the main beam cross section to reduce the dead load weight of the cross section, and to improve the rigidity of the cross section and wind resisting stability, etc. In addition, a cross beam is provided in the diagonal member anchorage position to integrate the two box beams. A wind tunnel test is performed using a 1/30 scale model to confirm the wind resisting stability. The diagonal member is structured with several PC steel members. At the same time, a stretching work carriage is developed and used which can establish 3 dimensional position and direction by a hydraulic jack. 7 figs.

  14. Comportamiento estructural y criterios de diseño de los puentes extradosados: visión general y estado del arte Structural behavior and design criteria of extradosed bridges: general insight and state of the art

    Directory of Open Access Journals (Sweden)

    José Benjumea

    2010-01-01

    Full Text Available Durante los últimos 10 años, los puentes extradosados se han convertido en una solución estructural atractiva alrededor del mundo, gracias a los buenos resultados obtenidos con las primeras realizaciones en Japón. Esta nueva tipología, reconocida generalmente como una solución intermedia entre los puentes atirantados y los de pretensado de viga cajón construidos por voladizos sucesivos, se ha convertido en una opción interesante. Por consiguiente, dado el interés que hoy en día existe alrededor de este tipo de puente, en este trabajo se presenta el contexto histórico que describe su origen, y se exponen la influencia de los principales elementos estructurales en el comportamiento del puente, y los criterios de diseño que han sido propuestos por investigadores en el tema. De esta manera, se espera ofrecer una visión general de la concepción y el comportamiento estructural de los puentes extradosados para que sea considerada una alternativa más de tipología estructural de puentes en nuestro medio.Over the past 10 years, Extradosed bridges have become an attractive structural type around the world, due to the good results obtained with the first bridges constructed in Japan. This new typology, generally recognized as an intermediate solution between cable stayed bridges and cantilever constructed prestressed box-girder bridges, because these take advantages of design and constructions methods of the other two typologies, has become an interesting option. Therefore, given the interest that exist about this type of bridge, in this paper the historical context that describes its origin, the influence of the principal structural elements and the design criteria proposed by researchers are presented. In this way it is expected to offer a general insight into the design conception and structural behavior of Extradosed Bridges, so that they may be considered as an alternative structure for bridges in the Americas.

  15. A Polish approach to FRP bridges

    Science.gov (United States)

    Siwowski, Tomasz; Rajchel, Mateusz

    2017-12-01

    The paper presents initial results of a new approach to FRP composite bridge construction that is presently being developed and tested in Poland. The concept combines lightweight concrete with FRP composites to create a durable highly optimised structure. The paper describes the bridge system itself and presents the research results on its development. The basic design is presented together with research results on its development: FEM analysis and a range of static test results of full-scale bridge beam experiments. The paper finishes with some test results of a full scale bridge that was constructed near Rzeszow in December 2015.

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

    International Nuclear Information System (INIS)

    Soomro, M.A.; Helepoto, I.A.

    2014-01-01

    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)

  17. STUDY OF BRIDGE DECK A REVIEW

    OpenAIRE

    MISS. KSHITIJA S. BALWAN , MR. V. G. KHURD , MR. S. S. CHOUGULE

    2018-01-01

    The objective of this study was to understand the meaning of bridge deck. To know the different forms of decks used in bridge design. To understand different methods used for analysis of deck and study of box girder and its evolution

  18. Rapid replacement/construction of bridges.

    Science.gov (United States)

    2012-11-01

    Bridges are a key element of the transportation system because they control system capacity and are normally built at : the highest cost to the system. Once a bridge reaches its useful design service life, it needs to be replaced or : reconstructed i...

  19. Seismic Passive Control of Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Hosam-Eddin M. Ali

    1995-01-01

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

  20. Guardrails for Use on Historic Bridges: Volume 1—Replacement Strategies

    OpenAIRE

    Frosch, Robert J.; Kreger, Michael E.; Clauss, Adam J.

    2016-01-01

    Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

  1. Engineering out motion: introduction of a de novo disulfide bond and a salt bridge designed to close a dynamic cleft on the surface of cytochrome b5.

    Science.gov (United States)

    Storch, E M; Daggett, V; Atkins, W M

    1999-04-20

    A previous molecular dynamics (MD) simulation of cytochrome b5 (cyt b5) at 25 degrees C displayed localized dynamics on the surface of the protein giving rise to the periodic formation of a cleft that provides access to the heme through a protected hydrophobic channel [Storch and Daggett (1995) Biochemistry 34, 9682]. Here we describe the production and testing of mutants designed to prevent the cleft from opening using a combination of experimental and theoretical techniques. Two mutants have been designed to close the surface cleft: S18D to introduce a salt bridge and S18C:R47C to incorporate a disulfide bond. The putative cleft forms between two separate cores of the protein: one is structural in nature and can be monitored through the fluorescence of Trp 22, and the other binds the heme prosthetic group and can be tracked via heme absorbance. An increase in motion localized to the cleft region was observed for each protein, except for the disulfide-containing variant, in MD simulations at 50 degrees C compared to simulations at 25 degrees C. For the disulfide-containing variant, the cleft remained closed. Both urea and temperature denaturation curves were nearly identical for wild-type and mutant proteins when heme absorbance was monitored. In contrast, fluorescence studies revealed oxidized S18C:R47C to be considerably more stable based on the midpoints of the denaturation transitions, Tm and U1/2. Moreover, the fluorescence changes for each protein were complete at approximately 50 degrees C and a urea concentration of approximately 3.9 M, significantly below the temperature and urea concentration (62 degrees C, 5 M urea) required to observe heme release. In addition, solvent accessibility based on acrylamide quenching of Trp 22 was lower in the S18C:R47C mutant, particularly at 50 degrees C, before heme release [presented in the accompanying paper (58)]. The results suggest that a constraining disulfide bond can be designed to inhibit dynamic cleft formation

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

    Science.gov (United States)

    Belykh, Igor; Jeter, Russell; Belykh, Vladimir

    2017-11-01

    Modern pedestrian and suspension bridges are designed using industry standard packages, yet disastrous resonant vibrations are observed, necessitating multimillion dollar repairs. Recent examples include pedestrian-induced vibrations during the opening of the Solférino Bridge in Paris in 1999 and the increased bouncing of the Squibb Park Bridge in Brooklyn in 2014. The most prominent example of an unstable lively bridge is the London Millennium Bridge, which started wobbling as a result of pedestrian-bridge interactions. Pedestrian phase locking due to footstep phase adjustment is suspected to be the main cause of its large lateral vibrations; however, its role in the initiation of wobbling was debated. We develop foot force models of pedestrians' response to bridge motion and detailed, yet analytically tractable, models of crowd phase locking. We use biomechanically inspired models of crowd lateral movement to investigate to what degree pedestrian synchrony must be present for a bridge to wobble significantly and what is a critical crowd size. Our results can be used as a safety guideline for designing pedestrian bridges or limiting the maximum occupancy of an existing bridge. The pedestrian models can be used as "crash test dummies" when numerically probing a specific bridge design. This is particularly important because the U.S. code for designing pedestrian bridges does not contain explicit guidelines that account for the collective pedestrian behavior.

  3. Features of monitoring system of physical state of urban bridges.

    Directory of Open Access Journals (Sweden)

    A.V. Bilchenko

    2011-12-01

    Full Text Available Abstract, the main features of urban bridge, structure are presented. The proposals concerning specialized management creation for exploitation, maintenance and reconstruction of bridges are developed. The essence of the new approach designed for the change of urban bridge structures physical state assessment system is stated.

  4. Response estimation for a floating bridge using acceleration output only

    NARCIS (Netherlands)

    Petersen, Øyvind Wiig; Øiseth, Ole; Nord, Torodd Skjerve; Lourens, E.; Sas, P.; Moens, D.; van de Walle, A.

    2016-01-01

    The Norwegian Public Roads Administration is reviewing the possibility of using floating bridges as fjord crossings. The dynamic behaviour of very long floating bridges with novel designs are prone to uncertainties. Studying the dynamic behaviour of existing bridges is valuable for understanding

  5. Overview of the National Timber Bridge Inspection Study

    Science.gov (United States)

    James P. Wacker; Brian K. Brashaw; Frank Jalinoos

    2013-01-01

    As many engineers begin to implement life cycle cost analyses within the preliminary bridge design phase, there is a significant need for more reliable data on the expected service life of highway bridges. Many claims are being made about the expected longevity of concrete and steel bridges, but few are based on actual performance data. Because engineers are least...

  6. Ways of ensuring the standard of bridge superstructures.

    OpenAIRE

    M.G. Malgin; V.I. Kiryan

    2011-01-01

    The structural features of welded railway bridges of the last century were considered. The basic causes of appearance of fatigue cracks in welded joints of railway bridges were assessed. Structural and technological ways of provision of the design life of operated and new-built welded railway bridges are discussed.

  7. Ways of ensuring the standard of bridge superstructures.

    Directory of Open Access Journals (Sweden)

    M.G. Malgin

    2011-12-01

    Full Text Available The structural features of welded railway bridges of the last century were considered. The basic causes of appearance of fatigue cracks in welded joints of railway bridges were assessed. Structural and technological ways of provision of the design life of operated and new-built welded railway bridges are discussed.

  8. A data management infrastructure for bridge monitoring

    Science.gov (United States)

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

    2015-04-01

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

  9. T-section glulam timber bridge modules : modeling and performance

    Science.gov (United States)

    Paul A. Morgan; Steven E. Taylor; Michael A. Ritter; John M. Franklin

    1999-01-01

    This paper describes the design, modeling, and testing of two portable timber bridges, each consisting of two noninterconnected longitudinal glued-laminated timber (glulam) deck panels 1.8 m (6 ft) wide. One bridge is 12.2 m (40 ft) long while the other bridge is 10.7 m (35 ft) long. The deck panels are fabricated in a unique double-tee cross section. The bridges...

  10. A Hierarchical Analysis of Bridge Decision Makers ... The Role of New Technology Adoption in the Timber Bridge Market: Special Project

    Science.gov (United States)

    Robert L. Smith; Robert J. Bush; Daniel L. Schmoldt

    1995-01-01

    Bridge design engineers and local highway officials make bridge replacement decisions across the United States. The Analytical Hierarchy Process was used to characterize the bridge material selection decision of these individuals. State Department of Transportation engineers, private consulting engineers, and local highway officials were personally interviewed in...

  11. Bridging worlds

    DEFF Research Database (Denmark)

    Rose, Jeremy; Memon, Saifullah Hassan

    2012-01-01

    This paper reports a case study where Soft Systems Methodology (SSM) was used to help automate a largely manual administrative (examination) information system in a Pakistani university. Various design suggestions for information system improvements, both administrative and IT-supported were made...

  12. Bridge element deterioration rates.

    Science.gov (United States)

    2008-10-01

    This report describes the development of bridge element deterioration rates using the NYSDOT : bridge inspection database using Markov chains and Weibull-based approaches. It is observed : that Weibull-based approach is more reliable for developing b...

  13. Bridge vehicle impact assessment.

    Science.gov (United States)

    2011-12-01

    Bridges in New York State have been experiencing close to 200 bridge hits a year. These : accidents are attributed to numerous factors including: improperly stored equipment on trucks; : violation of vehicle posting signs; illegal commercial vehicles...

  14. Bridge Scour Technology Transfer

    Science.gov (United States)

    2018-01-24

    Scour and flooding are the leading causes of bridge failures in the United States and therefore should be monitored. New applications of tools and technologies are being developed, tested, and implemented to reduce bridge scour risk. The National Coo...

  15. LTBP bridge performance primer.

    Science.gov (United States)

    2013-12-01

    "The performance of bridges is critical to the overall performance of the highway transportation system in the United States. However, many critical aspects of bridge performance are not well understood. The reasons for this include the extreme diver...

  16. Key Royale bridge five year evaluation.

    Science.gov (United States)

    2013-06-01

    This report describes the design, construction, instrumentation, and five-year evaluation of the Key Royale Bridge substructure. The primary focus was the evaluation of the implementation of highly reactive supplementary cementitious materials (SCM) ...

  17. Recessed floating pier caps for highway bridges.

    Science.gov (United States)

    1973-01-01

    Presented are alternate designs for two existing bridges in Virginia - one with steel beams and the other with prestressed concrete beams - whereby the pier caps are recessed within the depth of the longitudinal beams. The purpose of this recession i...

  18. Cross-Quint-Bridge Resistor

    Science.gov (United States)

    Hannaman, David J.; Lieneweg, Udo; Buehler, Martin G.; Mantalas, Linda

    1991-01-01

    Integrated-circuit conductive test pattern intended to provide data on effects of design widths and design spacings upon actual widths of conductive lines. Provides for electrical measurements both on lines of unknown width and on features having known dimensions. Data from measurements on five bridges used to determine four parameters of mathematical model describing system. In principle, pattern determines effects of width and spacing and interaction between them.

  19. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated......, and as an example the reliability profile and a sensitivity analyses for a corroded reinforced concrete bridge is shown....

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

    DEFF Research Database (Denmark)

    Park, Kiwoo; Chen, Zhe

    2013-01-01

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

  1. Fatigue Testing of Dental Bridges on Selected Examples

    Directory of Open Access Journals (Sweden)

    Urban Dariusz

    2017-03-01

    Full Text Available The paper presents example tests of the functional quality of selected designs of dental bridges. These were: porcelain bridges on a metal base (cobalt based alloy, porcelain bridges on a zirconia base (zirconia ceramic – Zirkon Zahn, and full zirconia bridges (Zirkon Zahn. For the purpose of the study, durability of bridges in cyclic fatigue testing was adopted as a measure of their quality. The tests were carried out on a Zwick Roell Z010 universal testing machine. They consisted in cyclic loading and unloading of dental bridges mounted on gypsum models at a loading force of F= 400 [N] and a frequency of load of f= 1 [Hz]. Each bridge was subjected to a cycle of 7200 loads. The results show that there are no significant differences in the functional quality of the bridges.

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

    Science.gov (United States)

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

    2013-11-08

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

  3. Violin Bridge Mobility Analysis under In-Plane Excitation

    Directory of Open Access Journals (Sweden)

    Cheng-Zhong Zhang

    2013-11-01

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

  4. Field performance of timber bridges. 11, Spearfish Creek stress-laminated box-beam bridge

    Science.gov (United States)

    J. P. Wacker; M. A. Ritter; K. Stanfill-McMillan

    The Spearfish Creek bridge was constructed in 1992 in Spearfish, South Dakota. It is a single-span, stress-laminated, box-beam superstructure. Performance of the bridge is being monitored for 5 years, beginning at installation. This report summarizes results for the first 3-1/2 years of monitoring and includes information on the design, construction, and field...

  5. Automatic Bridge Control System

    OpenAIRE

    M. Niraimathi; S.Sivakumar; R.Vigneshwaran; R.Vinothkumar; P.Babu

    2012-01-01

    Bridge vibration control is an important issue whose purpose is to extend the structural service life of bridges. Normally, the bridge is modeled as an elastic beam or plate subject to a moving vehicle. However, the moving truck on a bridge is a complicated problem that must still be researched. In this paper, wepropose a new method, to overcome the huge load in the bridge a load cell is used at the entry which will monitor the load continuously at both ends. To escape from the heavy water fl...

  6. Salt-bridge energetics in halophilic proteins.

    Science.gov (United States)

    Nayek, Arnab; Sen Gupta, Parth Sarthi; Banerjee, Shyamashree; Mondal, Buddhadev; Bandyopadhyay, Amal K

    2014-01-01

    Halophilic proteins have greater abundance of acidic over basic and very low bulky hydrophobic residues. Classical electrostatic stabilization was suggested as the key determinant for halophilic adaptation of protein. However, contribution of specific electrostatic interactions (i.e. salt-bridges) to overall stability of halophilic proteins is yet to be understood. To understand this, we use Adaptive-Poison-Boltzmann-Solver Methods along with our home-built automation to workout net as well as associated component energy terms such as desolvation energy, bridge energy and background energy for 275 salt-bridges from 20 extremely halophilic proteins. We then perform extensive statistical analysis on general and energetic attributes on these salt-bridges. On average, 8 salt-bridges per 150 residues protein were observed which is almost twice than earlier report. Overall contributions of salt-bridges are -3.0 kcal mol-1. Majority (78%) of salt-bridges in our dataset are stable and conserved in nature. Although, average contributions of component energy terms are equal, their individual details vary greatly from one another indicating their sensitivity to local micro-environment. Notably, 35% of salt-bridges in our database are buried and stable. Greater desolvation penalty of these buried salt-bridges are counteracted by stable network salt-bridges apart from favorable equal contributions of bridge and background terms. Recruitment of extensive network salt-bridges (46%) with a net contribution of -5.0 kcal mol-1 per salt-bridge, seems to be a halophilic design wherein favorable average contribution of background term (-10 kcal mol-1) exceeds than that of bridge term (-7 kcal mol-1). Interiors of proteins from halophiles are seen to possess relatively higher abundance of charge and polar side chains than that of mesophiles which seems to be satisfied by cooperative network salt-bridges. Overall, our theoretical analyses provide insight into halophilic signature in its

  7. Concrete-Filled Steel Tube Arch Bridges in China

    Directory of Open Access Journals (Sweden)

    Jielian Zheng

    2018-02-01

    Full Text Available In the past 20 years, great progress has been achieved in China in the construction of concrete-filled steel tube (CFST arch bridges and concrete arch bridges with a CFST skeleton. The span of these bridges has been increasing rapidly, which is rare in the history of bridge development. The large-scale construction of expressways and high-speed railways demands the development of long-span arch bridges, and advances in design and construction techniques have made it possible to construct such bridges. In the present study, the current status, development, and major innovative technologies of CFST arch bridges and concrete arch bridges with a CFST skeleton in China are elaborated. This paper covers the key construction technologies of CFST arch bridges, such as the design, manufacture, and installation of steel tube arch trusses, the preparation and pouring of in-tube concrete, and the construction of the world’s longest CFST arch bridge—the First Hejiang Yangtze River Bridge. The main construction technologies of reinforced concrete arch bridges are also presented, which include cable-stayed fastening-hanging cantilever assembly, adjusting the load by means of stay cables, surrounding the concrete for arch rib pouring, and so forth. In addition, the construction of two CFST skeleton concrete arch bridges—the Guangxi Yongning Yong River Bridge and the Yunnan–Guangxi Railway Nanpan River Bridge—is discussed. CFST arch bridges in China have already gained a world-leading position; with the continuous innovation of key technologies, China will become the new leader in promoting the development of arch bridges. Keywords: Concrete-filled steel tube (CFST arch bridge, Steel-reinforced concrete arch bridge, Cable-stayed fastening-hanging cantilever assembly, Vacuum-assisted pouring in-tube concrete, Adjusting load by stay cables

  8. Study of the time-dependent clear water scour around circular bridge piers

    Directory of Open Access Journals (Sweden)

    Aksoy Aysegul Ozgenc

    2017-03-01

    Full Text Available The local scour around bridge piers influences their stabilities and plays a key role in the bridge failures. The estimation of the maximum possible scour depth around bridge piers is an important step in the design of the bridge pier foundations. In this study, the temporal evolution of local scour depths as well as the equilibrium scour depths were analyzed.

  9. Half Bridge Inductive Heater

    Directory of Open Access Journals (Sweden)

    Zoltán GERMÁN-SALLÓ

    2015-12-01

    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.

  10. Drill pipe bridge plug

    International Nuclear Information System (INIS)

    Winslow, D.W.; Brisco, D.P.

    1991-01-01

    This patent describes a method of stopping flow of fluid up through a pipe bore of a pipe string in a well. It comprises: lowering a bridge plug apparatus on a work string into the pipe string to a position where the pipe bore is to be closed; communicating the pipe bore below a packer of the bridge plug apparatus through the bridge plug apparatus with a low pressure zone above the packer to permit the fluid to flow up through the bridge plug apparatus; engaging the bridge plug apparatus with an internal upset of the pipe string; while the fluid is flowing up through the bridge plug apparatus, pulling upward on the work string and the bridge plug apparatus and thereby sealing the packer against the pipe bore; isolating the pipe bore below the packer from the low pressure zone above the packer and thereby stopping flow of the fluid up through the pipe bore; disconnecting the work string from the bridge plug apparatus; and maintaining the bridge plug apparatus in engagement with the internal upset and sealed against the pipe bore due to an upward pressure differential applied to the bridge plug apparatus by the fluid contained therebelow

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

    OpenAIRE

    Shrikant D. Bobade *, Dr. Valsson Varghese

    2016-01-01

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

  12. “On a bridge in Berlin”

    DEFF Research Database (Denmark)

    Pihl, Ole Verner

    2013-01-01

    This is a self-reflective case study based on the development of the Graphic Novel: “On a bridge in Berlin.” The GN will be used as an introduction to the history of architecture as a part of the curriculum in Architecture and Design at Aalborg University, and as a more broadly introduction...... that jumps in time and place: it begins with Martin Heidegger´s quotation “The Bridge gathers to itself in its own way earth and sky, divinities and mortals”, and the bridge is a state of mind, a chronotope, a portal in time between past, present, and future. The methodological approach is based...

  13. Inspection Strategies for Concrete Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    1989-01-01

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

  14. Bridge over troubled water?

    DEFF Research Database (Denmark)

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

    2008-01-01

    The problem of integrating non-Western immigrants into Western welfare states is the focus of this paper. To address this issue, we suggest a social capital approach in which we apply the conceptual pair of bridging social capital (BR), which connects an individual to the broader social structure...... relationship between the levels of bridging and bonding capital, suggesting that bonding social capital in the immigrant group does not seem to impede the establishment of the bridging social capital needed for integration....

  15. The hepatic bridge.

    Science.gov (United States)

    Sugarbaker, Paul H

    2018-07-01

    The hepatic bridge forms a tunnel of liver parenchyma that may obscure peritoneal metastases associated with the round ligament. Visualization and then resection of nodules associated with this structure is necessary. The incidence of a hepatic bridge and the extent that it covered the round ligament was determined in consecutive patients. Extent of coverage of the round ligament by the hepatic bridge was determined: Class 1 indicates up to one-third of the round ligament obscured, Class 2 up to two-thirds and Class 3 more than two-thirds. In 102 patients in whom the round ligament of the liver could be completely visualized, 50 had a hepatic bridge. Class 1 was 22 (44%) of the bridges, Class 2 was 16 (32%) and Class 3 was 12 (24%). A hepatic bridge was more frequently present in 28 of 45 male patients (62%) vs. 22 of 57 female patients (38%). Approximately one-half of our patients having cytoreductive surgery for peritoneal metastases were observed to have a hepatic bridge. Up to 56% of these patients have Class 2 or 3 hepatic bridge and may require division of the hepatic bridge to completely visualize the contents of the tunnel created by this structure. Copyright © 2018 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

  16. Bridging the Gap

    DEFF Research Database (Denmark)

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

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

  17. Bridge health monitoring metrics : updating the bridge deficiency algorithm.

    Science.gov (United States)

    2009-10-01

    As part of its bridge management system, the Alabama Department of Transportation (ALDOT) must decide how best to spend its bridge replacement funds. In making these decisions, ALDOT managers currently use a deficiency algorithm to rank bridges that ...

  18. Long-term bridge performance high priority bridge performance issues.

    Science.gov (United States)

    2014-10-01

    Bridge performance is a multifaceted issue involving performance of materials and protective systems, : performance of individual components of the bridge, and performance of the structural system as a whole. The : Long-Term Bridge Performance (LTBP)...

  19. Three Cyanide-Bridged One-Dimensional Single Chain Co"I"I"I-Mn"I"I Complexes: Rational Design, Synthesis, Crystal Structures and Magnetic Properties

    International Nuclear Information System (INIS)

    Zhang, Daopeng; Zhao, Zengdian; Wang, Ping; Chen, Xia

    2012-01-01

    Two pyridinecarboxamide dicyanidecobalt(III) building blocks and two mononuclear seven-coordinated macrocycle manganese(II) compounds have been rationally selected to assemble cyanide-bridged heterobimetallic complexes, resulting in three cyanide-bridged Co"I"I"I-Mn"I"I complexes. Single X-ray diffraction analysis show that these complexes {[Mn(L"1)][Co(bpb)]}ClO_4·CH_3OH·0.5H_2O (1), {[Mn(L"2)][Co(bpb)]}ClO_4·0.5CH_3OH (2) and {[Mn(L"1)][Cobpmb]}ClO_4·H_2O (3) (L"1 = 3,6-diazaoctane-1,8-diamine, L"2 = 3,6-dioxaoctano-1,8- diamine: bpb"2"- = 1,2-bis(pyridine-2-carboxamido)benzenate, bpmb"2"- = 1,2-bis(pyridine-2-carboxamido)-4- methyl-benzenate) all present predictable one-dimensional single chain structures. The molecular structures of these one-dimensional complexes consists of alternating units of [Mn(L)]"2"+ (L = L"1 or L"2) and [Co(L')(CN)_2]"- (L' = bpb"2"-, or bpmb"2"-), forming a cyanide-bridged cationic polymeric chain with free ClO_4"- as the balance anion. The coordination geometry of manganese(II) ion in the three one-dimensional complexes is a slightly distorted pentagonal-bipyrimidal with two cyanide nitrogen atoms at the trans positions and N_5 or N_3O_2 coordinating mode at the equatorial plane from ligand L"1 or L"2. Investigation over magnetic properties of these complexes reveals that the very weak magnetic coupling between neighboring Mn(II) ions connected by the diamagnetic dicyanidecobalt(III) building block. A best-fit to the magnetic susceptibility of complex 1 leads to the magnetic coupling constants J = .0.084(3) cm"-"1

  20. Probabilistic FE analysis of a cable stayed composite bridge

    NARCIS (Netherlands)

    Boer, A. de; Waarts, P.H.

    1999-01-01

    This paper describes the design of a new cable stayed composite bridge near Kampen in the Netherlands. In the design process, the safety of bridges is insured by means of partial safety factors for both strength and load parameters. As a result it is generally accepted that the structure as a whole

  1. 49 CFR 237.131 - Design.

    Science.gov (United States)

    2010-10-01

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

  2. National Bridge Inventory System (NBI)

    Data.gov (United States)

    Department of Transportation — The NBI System is the collection of bridge inspection information and costs associated with bridge replacements of structurally deficient bridges on and off the NHS....

  3. Dragon bridge - the world largest dragon-shaped (ARCH steel bridge as element of smart city

    Directory of Open Access Journals (Sweden)

    Chinh Luong Minh

    2016-01-01

    Full Text Available Dragon Bridge - The world’s largest dragon-shaped steel bridge, with an installation cost of $85 million USD, features 6 lanes for two separate directions, 666 meters of undulating steel in the shape of a dragon in the Ly Dynasty, the symbol of prosperity in Vietnamese culture. This unique and beautifully lit bridge, which also breathes fire and sprays water. It’s the purposeful integration of the lighting hardware articulates the dragon’s form, and the fire-breathing dragon head. This project transcends the notion of monumental bridge with dynamic colour-changing lighting, creating an iconic sculpture in the skyline that is both reverent and whimsical. The signature feature of the bridge was the massive undulating support structure resembling a dragon flying over the river. The dragon is prominent in Vietnamese culture as a symbol of power and nobility. Dragon Bridge stands out as a model of innovation. It has received worldwide attention in the design community and from the global media for its unique arch support system. Dragon Bridge serves as an example of how aesthetic quality of a design can serve cultural, economic and functional purposes. The article presents design solutions of the object and the evaluation of the technical condition before putting the facility into service.

  4. Bridge the Gap

    DEFF Research Database (Denmark)

    Marselis, Randi

    2017-01-01

    This article focuses on photo projects organised for teenage refugees by the Society for Humanistic Photography (Berlin, Germany). These projects, named Bridge the Gap I (2015), and Bridge the Gap II (2016), were carried out in Berlin and brought together teenagers with refugee and German...

  5. The floating water bridge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Woisetschlaeger, Jakob; Gatterer, Karl; Maier, Eugen; Pecnik, Rene; Holler, Gert; Eisenkoelbl, Helmut

    2007-01-01

    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

  6. Rational Design of a Highly Potent and Selective Peptide Inhibitor of PACE4 by Salt Bridge Interaction with D160 at Position P3.

    Science.gov (United States)

    Dianati, Vahid; Shamloo, Azar; Kwiatkowska, Anna; Desjardins, Roxane; Soldera, Armand; Day, Robert; Dory, Yves L

    2017-08-08

    PACE4, a member of the proprotein convertases (PCs) family of serine proteases, is a validated target for prostate cancer. Our group has developed a potent and selective PACE4 inhibitor: Ac-LLLLRVKR-NH 2 . In seeking for modifications to increase the selectivity of this ligand toward PACE4, we replaced one of its P3 Val methyl groups with a basic group capable of forming a salt bridge with D160 of PACE4. The resulting inhibitor is eight times more potent than the P3 Val parent inhibitor and two times more selective over furin, because the equivalent salt bridge with furin E257 is not optimal. Moreover, the β-branched nature of the new P3 residue favors the extended β-sheet conformation usually associated with substrates of proteases. This work provides new insight for better understanding of β-sheet backbone-backbone interactions between serine proteases and their peptidic ligands. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Probabilistic and sensitivity analysis of Botlek Bridge structures

    Directory of Open Access Journals (Sweden)

    Králik Juraj

    2017-01-01

    Full Text Available This paper deals with the probabilistic and sensitivity analysis of the largest movable lift bridge of the world. The bridge system consists of six reinforced concrete pylons and two steel decks 4000 tons weight each connected through ropes with counterweights. The paper focuses the probabilistic and sensitivity analysis as the base of dynamic study in design process of the bridge. The results had a high importance for practical application and design of the bridge. The model and resistance uncertainties were taken into account in LHS simulation method.

  8. Active Control of Long Bridges Using Flaps

    DEFF Research Database (Denmark)

    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 the streamlined part of the edge of the girder. Additional aerodynamic derivatives are shown for the flaps and it is shown how methods already developed can be used to estimate the flutter wind velocity for a bridge section with flaps. As an example, the flutter wind velocity is calculated for 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....

  9. Active aerodynamic stabilisation of long suspension bridges

    DEFF Research Database (Denmark)

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

    2004-01-01

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

  10. Planning of Tatara Bridge. Chodai shachokyo-Tataraohashi-no keikaku gaiyo

    Energy Technology Data Exchange (ETDEWEB)

    Okukawa, A. (Honshu-Shikoku Bridge Authority, Tokyo (Japan))

    1991-12-05

    The outline of the Tatara Bridge is given to introduce the features of the entire structural system and fundamental problems concerning the construction of the huge cable stayed bridge. The central span of the bridge is 890m. The topography and geological features of the bridging point are reviewed, and social conditions such as being in a national park, safety for sailing, etc. are taken into consideration for various technological studies on the construction of the huge bridge. Bridge piers are provided in the side spans and appropriate counter weight is loaded to design a more economical bridge which is more suitable for the topography as compared with a suspension bridge. The cable stayed bridge requires no anchorage which is necessary for a suspension bridge with very little topological alteration, and an excellent result is obtained both in cost and term of construction as compared with a suspension bridge. The rigidity of the cable stayed bridge is high, and the stability of the resistance to wind of the structure is also very satisfactory. As a result, it is concluded that the bridge can be designed and constructed using currently available technologies, and a cable stayed bridge is selected in August, 1990 as the type for the Tatara Bridge. 9 figs., 1 tab.

  11. Simple model of cable-stayed bridge deck subjected to static wind loading

    Science.gov (United States)

    Kang, Yi-Lung; Wang, Yang Cheng

    1997-05-01

    Cable-stayed bridges have been known since 18th century with aesthetics design. The structural system and the structural behavior are significantly different from those of continuous bridges. Compared to continuous bridge, cable- stayed bridges have more flexure bridge deck than those of continuous bridges.On the other hand, cable-stayed bridges have less stiffness to resist wind loading especially for lateral loads. The first considering of bridge engineering is safety. In 1940's, Tacoma Narrows Suspension Bridge destroyed by wind loading is a good example even though it is not a cable-stayed bridge. After the bridge was destroyed, a lot of research articles have been published regarding cable supported bridge subjected to wind loading. In recent days, high strength materials have been served. The bridge engineers use the advantages to expand the span length of cable-stayed bridges. Due to the span length increased and the use of high strength materials, cable- stayed bridges have more significant nonlinear behavior subjected to wind loading. In this paper, a slice bridge deck of cable-stayed bridge connected to internal support cables is considered. The deck has been considered to be subjected to lateral static wind loading. Since cables can not take compressive force, the deck has strongly nonlinear behavior even though the materials are linear elastic. Several primary load combinations have ben considered in this paper such as the bridge deck supposed to be moved horizontally without rotation or the bridge deck supposed to be moved horizontally with rotational deformation. The mathematical formulas and the numerical solutions are found and represented in graphical forms. The results can be provided to bridge designers and researchers for further study of this type of structure subjected to wind loading.

  12. U.S. Geological Survey - Virginia Department of Transportation: Bridge scour pilot study

    Science.gov (United States)

    Austin, Samuel H.

    2018-02-27

    BackgroundCost effective and safe highway bridge designs are required to ensure the long-term sustainability of Virginia’s road systems. The streamflows that, over time, scour streambed sediments from bridge piers inherently affect bridge safety and design costs. To ensure safety, bridge design must anticipate streambed scour at bridge piers over the lifespan of a bridge. Until recently Federal Highway Administration (FHWA) guidance provided only for scour estimates of granular, noncohesive, highly erosive material yielding overestimates of scour potential in instances when streambed materials offer some resistance to scour. This study seeks to estimate stream power and streambed scour for these more resistive sites, with bridge piers potentially established in cohesive soil or erodible rock. This new knowledge may provide significant construction cost savings while ensuring design and construction of safe highway bridges.

  13. Data collection and evaluation of continuity detail for John James Audubon Bridge No. 61390613004101.

    Science.gov (United States)

    2014-10-01

    This report summarizes findings from monitoring data that was collected over a two-year period from Bridge No. : 61390613004101 in the John James Audubon Project, which was formerly designated as Bridge #2 prior to : construction completion. The brid...

  14. Continuity diaphragm for skewed continuous span precast prestressed concrete girder bridges : technical summary report.

    Science.gov (United States)

    2004-03-01

    Most highway bridges are built as cast-in-place : reinforced concrete slabs and prestressed concrete : girders. The shear connectors on the top of the girders : assure composite action between the slabs and : girders. The design guidelines for bridge...

  15. Bridge technology report

    CERN Document Server

    2013-01-01

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

  16. Effects of Irregular Bridge Columns and Feasibility of Seismic Regularity

    Science.gov (United States)

    Thomas, Abey E.

    2018-05-01

    Bridges with unequal column height is one of the main irregularities in bridge design particularly while negotiating steep valleys, making the bridges vulnerable to seismic action. The desirable behaviour of bridge columns towards seismic loading is that, they should perform in a regular fashion, i.e. the capacity of each column should be utilized evenly. But, this type of behaviour is often missing when the column heights are unequal along the length of the bridge, allowing short columns to bear the maximum lateral load. In the present study, the effects of unequal column height on the global seismic performance of bridges are studied using pushover analysis. Codes such as CalTrans (Engineering service center, earthquake engineering branch, 2013) and EC-8 (EN 1998-2: design of structures for earthquake resistance. Part 2: bridges, European Committee for Standardization, Brussels, 2005) suggests seismic regularity criterion for achieving regular seismic performance level at all the bridge columns. The feasibility of adopting these seismic regularity criterions along with those mentioned in literatures will be assessed for bridges designed as per the Indian Standards in the present study.

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

    Science.gov (United States)

    Putnam, Cynthia

    2010-01-01

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

  18. Bridge removal plan requirements.

    Science.gov (United States)

    2011-04-15

    This report provides resources that detail specifications and guidelines related to bridge removal plans across the : United States. We have organized the information into three sections: : ! National Guidance : Includes language from AASHTO specific...

  19. Bridged Race Population Estimates

    Data.gov (United States)

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

  20. Bridging Humanism and Behaviorism.

    Science.gov (United States)

    Chu, Lily

    1980-01-01

    Humanistic behaviorism may provide the necessary bridge between behaviorism and humanism. Perhaps the most humanistic approach to teaching is to learn how certain changes will help students and how these changes can be accomplished. (Author/MLF)

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

    Science.gov (United States)

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

    2016-04-01

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

  2. Longest cable-stayed bridge TATARA; Longest shachokyo Tatara Ohashi

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, K. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1998-06-15

    The world`s longest cable-stayed bridge Tatara having a central span of 890 m had the both ends closed in August 1997, linking Namakuchi Island and Omishima Island. Final finishing work is continuing for opening of the West Seto Expressway in the spring of 1999. A cable-stayed bridge supports the bridge girders by perpendicular components of tensile force of cables stayed obliquely. On the other hand, there is a concern that the girders may have axial compression force generated due to horizontal components of the force from the cable tensile force, which can cause buckling of the girders. Therefore, in order to suspend the girders efficiently by increasing the perpendicular components of the cable force, and moreover to suppress the axial compression force on the girders, it is more advantageous to make bridge towers high, hence the towers of this bridge are highest among the bridges on the Shimanami Ocean Road. This bridge whose long girders are stayed with 21-stage multi cables presented a problem in designing the buckling in steel girders near the towers due to the horizontal components of the force generated by the bridge. Discussions were given, therefore, by using load withstanding force experiments using a whole bridge model of 1/50 scale, buckling experiments on full-size reinforcing plate models, and load withstanding force analysis using a tower model. A number of other technical discussions were repeated, by which the world`s longest cable-stayed bridge was completed. 9 figs., 1 tab.

  3. Discrete vortex method simulations of aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan

    , and to determine aerodynamic forces and the corresponding flutter limit. A simulation of the three-dimensional bridge responseto turbulent wind is carried out by quasi steady theory by modelling the bridge girder as a line like structure [2], applying the aerodynamic load coefficients found from the current version......The meshless and remeshed Discrete Vortex Method (DVM) has been widely used in academia and by the industry to model two-dimensional flow around bluff bodies. The implementation “DVMFLOW” [1] is used by the bridge design company COWI to determine and visualise the flow field around bridge sections...

  4. Research on Local Scour at Bridge Pier under Tidal Action

    Directory of Open Access Journals (Sweden)

    Wang Jianping

    2015-01-01

    Full Text Available Through the local scour test at bridge pier under tidal action in a long time series, this paper observes the growing trend of the deepest point of local scour at bridge pier under tidal conditions with different characteristic parameters, analyzes the impact of repeat sediment erosion and deposition in the scouring pit caused by reversing current on the development process of the scouring pit, and clarifies the relation between the tide and local scouring depth at bridge pier under steady flow conditions, so as to provide a scientific basis for bridge design and safe operation of estuary and harbor areas.

  5. Cooperativity of complex salt bridges

    OpenAIRE

    Gvritishvili, Anzor G.; Gribenko, Alexey V.; Makhatadze, George I.

    2008-01-01

    The energetic contribution of complex salt bridges, in which one charged residue (anchor residue) forms salt bridges with two or more residues simultaneously, has been suggested to have importance for protein stability. Detailed analysis of the net energetics of complex salt bridge formation using double- and triple-mutant cycle analysis revealed conflicting results. In two cases, it was shown that complex salt bridge formation is cooperative, i.e., the net strength of the complex salt bridge...

  6. Computer modeling of road bridge for simulation moving load

    Directory of Open Access Journals (Sweden)

    Miličić Ilija M.

    2016-01-01

    Full Text Available In this paper is shown computational modelling one span road structures truss bridge with the roadway on the upper belt of. Calculation models were treated as planar and spatial girders made up of 1D finite elements with applications for CAA: Tower and Bridge Designer 2016 (2nd Edition. The conducted computer simulations results are obtained for each comparison of the impact of moving load according to the recommendations of the two standards SRPS and AASHATO. Therefore, it is a variant of the bridge structure modeling application that provides Bridge Designer 2016 (2nd Edition identical modeled in an environment of Tower. As important information for the selection of a computer applications point out that the application Bridge Designer 2016 (2nd Edition we arent unable to treat the impacts moving load model under national standard - V600. .

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  8. Dynamic loads during failure risk assessment of bridge crane structures

    Science.gov (United States)

    Gorynin, A. D.; Antsev, V. Yu; Shaforost, A. N.

    2018-03-01

    The paper presents the method of failure risk assessment associated with a bridge crane metal structure at the design stage. It also justifies the necessity of taking into account dynamic loads with regard to the operational cycle of a bridge crane during failure risk assessment of its metal structure.

  9. Summer Bridge Programs. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2016

    2016-01-01

    "Summer bridge programs" are designed to ease the transition to college and support postsecondary success by providing students with the academic skills and social resources needed to succeed in a college environment. These programs occur in the summer "bridge" period between high school and college. Although the content of…

  10. Guidelines to restoring structural integrity of covered bridge members

    Science.gov (United States)

    Ronald W. Anthony

    2018-01-01

    These guidelines are designed for decision makers (selectmen, county commissioners, city planners, preservation officers, etc.) that have responsibility for repairing and maintaining existing covered bridges to help them understand what goes into making effective decisions about how, and when, to repair a covered bridge. The purpose of these guidelines is to present...

  11. Very High Frequency Half Bridge DC/DC Converter

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  12. Pennsylvania hardwood timber bridges : field performance after 10 years

    Science.gov (United States)

    James P. Wacker; Carlito Calil

    2004-01-01

    Several hardwood demonstration timber bridges were built by the Pennsylvania Department of Transportation in the early nineteen nineties. These bridge superstructures are of the recently developed stress-laminated deck design-type using Red Oak lumber laminations that were pressure-treated with creosote preservatives. This paper will describe the data acquisition...

  13. Wireless data collection retrievals of bridge inspection/management information.

    Science.gov (United States)

    2017-02-28

    To increase the efficiency and reliability of bridge inspections, MDOT contracted to have a 3D-model-based data entry application for mobile tablets developed to aid inspectors in the field. The 3D Bridge App is a mobile software tool designed to fac...

  14. Integral abutment bridge for Louisiana's soft and stiff soils.

    Science.gov (United States)

    2016-03-01

    Integral abutment bridges (IABs) have been designed and constructed in a few US states in the past few : decades. The initial purpose of building such bridges was to eliminate the expansion joints and resolve the : joint-induced problems. Although IA...

  15. Comparative durability of timber bridges in the USA

    Science.gov (United States)

    James P. Wacker; Brian K. Brashaw

    2017-01-01

    As engineers begin to utilize life-cycle-cost design approaches for timber bridges, there is a necessity for more reliable data about their durability and expected service life. This paper summarizes a comprehensive effort to assess the current condition of more than one hundred timber highway bridge superstructures throughout the United States. This national study was...

  16. Learning Bridges: A Role for Mobile Technologies in Education

    Science.gov (United States)

    Vavoula, Giasemi; Sharples, Mike; Lonsdale, Peter; Rudman, Paul; Meek, Julia

    2007-01-01

    MyArtSpace is a service for children to spread their learning between schools and museums using mobile phones linked to a personal Web space. Using MyArtSpace as an example, the authors discuss the possibilities for mobile technology to form bridges between formal and informal learning. They also offer guidelines for designing such bridges.…

  17. Investigation of Aerodynamic Interference between Twin Deck Bridges

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-05-01

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

  18. MAFIA simulation and cold model test of three types of bridge coupler

    International Nuclear Information System (INIS)

    Chang, C.R.; Yao, C.G.; Swenson, D.A.; Funk, L.W.; Raparia, D.

    1992-01-01

    In the new design of the SSC CCL, the total number of bridge couplers has increased from 50 to 63, and their maximum length increased from 37.2 to 46.1 cm. Choosing a bridge coupler that gives maximum coupling, minimum power flow, phase shift and fabrication cost becomes important. The conventional TM010 single cavity bridge coupler used in LAMPF and Fermilab will have severe mode mixing problem when the bridge length is over 30 cm, and the coupling is very weak. Three types of bridge coupler have been proposed: (1) TM012 single cavity bridge coupler; (2) electrically coupled multi-cavity bridge coupler and (3) magnetically coupled multi-cavity bridge coupler. This paper presents both MAFIA simulations and cold model tests results. Each bridge coupler has its unique characteristics with advantages and disadvantages, but all three are superior to the conventional coupler. (Author) 6 figs., tab., 2 refs

  19. Three Dimensional Analysis of Pier Extension and Guide Wall Design Alternatives to Mitigate Local Scour Risk at the BNSF Railroad Bridge Downstream of the Prado Dam

    Energy Technology Data Exchange (ETDEWEB)

    Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Bojanowski, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Sinha, N. [Argonne National Lab. (ANL), Argonne, IL (United States); Kerenyi, K [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-03-01

    The primary objectives of the computational fluid dynamics (CFD) analysis are (1) to verify that the design concept of using wedge shaped pier extensions to divert flow around piers as a scour counter measure has the intended effect on the flow, (2) to refine the design of the length and orientation of the pier extensions within the channel and (3) to optimize the guide walls that will protect a set of outer piers and the abutments on each side of the channel. The original proposed design is shown in Figure 1.3. The results of this effort are the recommended designs that are judged to be the best designs based on results from the set of test cases run combined with engineering judgment. The refined designs from the CFD analysis are expected to be tested in a limited set of physical model experiments to verify that they work well.

  20. Long Span Bridges in Scandinavia

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1998-01-01

    The first Scandinavian bridge with a span of more than 500 m was the Lillebælt Suspension Bridge opened to traffic in 1970.Art the end of the 20th century the longest span of any European bridge is found in the Storebælt East Bridge with a main span of 1624 m. Also the third longest span in Europe...... is found in Scandinavia - the 1210 m span of the Höga Kusten Bridge in Sweden.The Kvarnsund Bridge in Norway was at the completion in 1991 the longest cable-stayed bridge in the world, and the span of 530 m is still thge longest for cable-stayed bridges in concrete. The Øresund Bridge with its sapn of 490...

  1. Nonlinearity in oscillating bridges

    Directory of Open Access Journals (Sweden)

    Filippo Gazzola

    2013-09-01

    Full Text Available We first recall several historical oscillating bridges that, in some cases, led to collapses. Some of them are quite recent and show that, nowadays, oscillations in suspension bridges are not yet well understood. Next, we survey some attempts to model bridges with differential equations. Although these equations arise from quite different scientific communities, they display some common features. One of them, which we believe to be incorrect, is the acceptance of the linear Hooke law in elasticity. This law should be used only in presence of small deviations from equilibrium, a situation which does not occur in widely oscillating bridges. Then we discuss a couple of recent models whose solutions exhibit self-excited oscillations, the phenomenon visible in real bridges. This suggests a different point of view in modeling equations and gives a strong hint how to modify the existing models in order to obtain a reliable theory. The purpose of this paper is precisely to highlight the necessity of revisiting the classical models, to introduce reliable models, and to indicate the steps we believe necessary to reach this target.

  2. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

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

  3. 47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section 80.1007 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Bridge-to-Bridge Act § 80.1007 Bridge-to-bridge radiotelephone installation. Use of the bridge-to-bridge...

  4. Analysis of Static Load Test of a Masonry Arch Bridge

    Science.gov (United States)

    Shi, Jing-xian; Fang, Tian-tian; Luo, Sheng

    2018-03-01

    In order to know whether the carrying capacity of the masonry arch bridge built in the 1980s on the shipping channel entering and coming out of the factory of a cement company can meet the current requirements of Level II Load of highway, through the equivalent load distribution of the test vehicle according to the current design specifications, this paper conducted the load test, evaluated the bearing capacity of the in-service stone arch bridge, and made theoretical analysis combined with Midas Civil. The results showed that under the most unfavorable load conditions the measured strain and deflection of the test sections were less than the calculated values, the bridge was in the elastic stage under the design load; the structural strength and stiffness of the bridge had a certain degree of prosperity, and under the in the current conditions of Level II load of highway, the bridge structure was in a safe state.

  5. Durability of Materials in Pearl-Chain Bridges

    DEFF Research Database (Denmark)

    Lund, Mia Schou Møller

    . The construction of the Pearl-Chain arch is simple. The arch is assembled on its side, next to the road that the bridge will span, by placing a number of plane prefabricated Super-Light Decks that consist of lightweight aggregate concrete and conventional concrete, in the desired arch shape. Mortar joints are cast...... is stabilized by casting a fill material between the spandrel walls of the arch. Finally, the road surface is cast on top of the fill material. New bridges are designed for a service lifetime of at least 100 years. Hence, the specifications of the materials used in Pearl-Chain Bridges are high. This PhD study...... and pervious concrete were also investigated. The most suitable fill material for Pearl-Chain Bridges depends on the particular bridge design; the results obtained and presented in the present PhD study provide guidance on how to decide which fill material is most suitable regarding strength, permeability...

  6. Bridge approach slabs for Missouri DOT field evaluation of alternative and cost efficient bridge approach slabs.

    Science.gov (United States)

    2013-05-01

    Based on a recent study on cost efficient alternative bridge approach slab (BAS) designs (Thiagarajan et : al. 2010) has recommended three new BAS designs for possible implementation by MoDOT namely a) 20 feet cast-inplace : slab with sleeper slab (C...

  7. Breaking down Barriers: A Bridge Program Helps First-Year Biology Students Connect with Faculty

    Science.gov (United States)

    Cooper, Katelyn M.; Ashley, Michael; Brownell, Sara E.

    2018-01-01

    Summer bridge programs often aim to build social connections for first-year students to ease their transition into college, yet few studies have reported on bridge programs successfully leading to these outcomes. We backward designed a summer bridge program for incoming biology majors to increase the comfort and connections among students and…

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

    DEFF Research Database (Denmark)

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

    1977-01-01

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

  9. Long term monitoring of carbon composite strands in the Penobscot-Narrows bridge.

    Science.gov (United States)

    2015-06-01

    The Penobscot-Narrows Bridge was constructed between May 2003 and December 2006. The bridge is a cable-stayed design with twin pylons and a 2,120-foot span. This cable-stayed bridge features a cradle stay system that : allows for each cable strand in...

  10. The Bridge of Mandolin County

    Science.gov (United States)

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

    1999-12-01

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

  11. Bridge deterioration models to support Indiana's bridge management system.

    Science.gov (United States)

    2016-02-01

    An effective bridge management system that is equipped with reliable deterioration models enables agency engineers to carry out : monitoring and long-term programming of bridge repair actions. At the project level, deterioration models help the agenc...

  12. Development of bridge girder movement criteria for accelerated bridge construction.

    Science.gov (United States)

    2014-06-01

    End diaphragms connect multiple girders to form a bridge superstructure system for effective resistance to earthquake loads. Concrete : girder bridges that include end diaphragms consistently proved to perform well during previous earthquake events. ...

  13. Design and evaluation of new Tc-99m-labeled lactam bridge-cyclized alpha-MSH peptides for melanoma imaging.

    Science.gov (United States)

    Guo, Haixun; Gallazzi, Fabio; Miao, Yubin

    2013-04-01

    The purpose of this study was to examine the melanoma targeting and imaging properties of new (99m)Tc-labeled lactam bridge-cyclized alpha-melanocyte stimulating hormone (α-MSH) peptides using bifunctional chelating agents. MAG3-GGNle-CycMSH(hex), AcCG3-GGNle-CycMSH(hex), and HYNIC-GGNle-CycMSH(hex) peptides were synthesized, and their melanocortin-1 (MC1) receptor binding affinities were determined in B16/F1 melanoma cells. The biodistribution of (99m)Tc-MAG3-GGNle-CycMSH(hex), (99m)Tc-AcCG3-GGNle-CycMSH(hex), (99m)Tc(CO)3-HYNIC-GGNle-CycMSH(hex), and (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) were determined in B16/F1 melanoma-bearing C57 mice at 2 h postinjection to select a lead peptide for further evaluation. The melanoma targeting and imaging properties of (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) were further examined because of its high melanoma uptake and fast urinary clearance. The IC50 values of MAG3-GGNle-CycMSH(hex), AcCG3-GGNle-CycMSH(hex), and HYNIC-GGNle-CycMSH(hex) were 1.0 ± 0.05, 1.2 ± 0.19, and 0.6 ± 0.04 nM in B16/F1 melanoma cells, respectively. Among these four (99m)Tc-peptides, (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) exhibited the highest melanoma uptake (14.14 ± 4.90% ID/g) and fastest urinary clearance (91.26 ± 1.96% ID) at 2 h postinjection. (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) showed high tumor to normal organ uptake ratios except for the kidneys. The tumor/kidney uptake ratios of (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) were 2.50 and 3.55 at 4 and 24 h postinjection. The melanoma lesions were clearly visualized by SPECT/CT using (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) as an imaging probe at 2 h postinjection. Overall, high melanoma uptake coupled with fast urinary clearance of (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) highlighted its potential for metastatic melanoma detection in the future.

  14. Demonstration of Thermoplastic Composite I-Beam Design Bridge at Camp Mackall, NC: Final Report on Projects FY08-16 and FY09-31

    Science.gov (United States)

    2017-12-01

    of the earliest designs had the product performing well when new, but sagging over time. Successful applications for unreinforced plastic lumber...construction curbs, removable speed bumps, parking lot wheel stops, and bollards. Since then, manufacturers have learned to create designs with lower stress...crystalline polymer product as part of the manufacturing process leads to voids in the interior cross-section due to thermodynamic and physical chemistry

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

    Directory of Open Access Journals (Sweden)

    Lei Yan

    2016-01-01

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

  16. Nonlinear seismic analysis of continuous RC bridge

    Directory of Open Access Journals (Sweden)

    Čokić Miloš M.

    2017-01-01

    Full Text Available Nonlinear static analysis, known as a pushover method (NSPA is oftenly used to study the behaviour of a bridge structure under the seismic action. It is shown that the Equivalent Linearization Method - ELM, recommended in FEMA 440, is appropriate for the response analysis of the bridge columns, with different geometric characteristics, quantity and distribution of steel reinforcement. The subject of analysis is a bridge structure with a carriageway plate - a continuous beam with three spans, with the 24 + 40 + 24 m range. Main girder is made of prestressed concrete and it has a box cross section of a constant height. It is important to study the behaviour, not only in the transverse, but also in the longitudinal direction of the bridge axis, when analysing the bridge columns exposed to horizontal seismic actions. The columns were designed according to EN1992, parts 1 and 2. Seismic action analysis is conducted according to EN 1998: 2004 standard. Response spectrum type 1, for the ground type B, was applied and the analysis also includes 20% of traffic load. The analysis includes the values of columns displacement and ductility. To describe the behaviour of elements under the earthquake action in both - longitudinal and transverse direction, pushover curves were formed.

  17. BUILDING "BRIDGES" WITH QUALITY ASSURANCE

    Science.gov (United States)

    The papr describes how, rather than building "bridges" across centuries, quality assurance (QA) personnel have the opportunity to build bridges across technical disciplines, between public and private organizations, and between different QA groups. As reviewers and auditors of a...

  18. Bridge-Vehicle Impact Assessment

    Science.gov (United States)

    2011-08-01

    Bridges in New York State have been experiencing close to 200 bridge hits a year. These : accidents are attributed to numerous factors including: improperly stored equipment on trucks; : violation of vehicle posting signs; illegal commercial vehicles...

  19. Virginia Bridge Information Systems Laboratory.

    Science.gov (United States)

    2014-06-01

    This report presents the results of applied data mining of legacy bridge databases, focusing on the Pontis and : National Bridge Inventory databases maintained by the Virginia Department of Transportation (VDOT). Data : analysis was performed using a...

  20. Public response to bridge colors.

    Science.gov (United States)

    1973-01-01

    To determine people's reactions to bridges painted in colors as white, yellow, green, blue, red, brown, black, and aluminum, two test bridges were selected in Charlottesville, Virginia. One was painted a different color each month and the other was k...

  1. Modal analysis of cable-stayed UHPC bridge

    Directory of Open Access Journals (Sweden)

    Tej Petr

    2017-01-01

    Full Text Available This paper deals with the dynamic analysis of cable-stayed UHPC bridge over the Vltava river near town Melnik in Czech Republic, Europe. Bridge serves for pedestrians and cyclists. This work aims to familiarize the reader with dynamic calculations carried out and the results obtained, describing the dynamic properties of proposed bridge. The construction of bridge is designed as a cable-stayed structure with prestressed bridge deck consisting of prefabricated UHPC panels and reversed “V” shaped steel pylon with height of approximately 40 meters. The deck is anchored using 24 steel hangers in one row in a steel pylon - 17 ropes in the main span and 7 cables on the other side. Range of the main span is 99.18 meters and the secondary span is 31.9 m. Deck width is 4.5 meters with 3.0 meters passing space. The bridge is designed for the possibility of passage of vehicles weighting up to 3.5 tonnes. Deck panels are made of UHPC with reinforcement. At the edge of the bridge on the side of the shorter span the bridge deck is firmly connected with abutment and on the other deck it is stored using a pair of sliding bearings.

  2. Phase I development of an aesthetic, precast concrete bridge rail.

    Science.gov (United States)

    2012-02-01

    Precast concrete bridge rail systems offer several advantages over traditional cast-in-place rail designs, including reduced construction : time and costs, installation in a wide range of environmental conditions, easier maintenance and repair, impro...

  3. Experimental studies on multicellular GFRP bridge deck panels ...

    Indian Academy of Sciences (India)

    M P MUTHURAJ

    2017-11-20

    Nov 20, 2017 ... design of a new bridge deck panel made of GFRP. .... cient manufacturing processes with minimal wastage. But re-use of the remaining FRP elements during manufacture ... Energy consumption for production of different.

  4. Development of precast bridge deck overhang system : technical report.

    Science.gov (United States)

    2011-07-01

    The implementation of full-depth, precast overhang panel systems has the potential to improve constructability, : productivity, and make bridges more economical. Initial testing and analyses reported in the 0-6100-2 report resulted in : a design that...

  5. structural reliability of the nigerian grown abura timber bridge beam

    African Journals Online (AJOL)

    ENGR. J. I. AGUWA

    2013-07-02

    Jul 2, 2013 ... Structural analysis and deterministic design of a timber bridge beam using the Nigerian ... practice especially when it involves naturally occuring materials .... the beam due to distributed loads is; from [15]. (4). It is assumed that ...

  6. reliability assessment of stringers spacings in bridges as function

    African Journals Online (AJOL)

    user

    A timber bridge deck is modelled on timber stringers in accordance with current .... simple linear formulation for supporting stringers ... new generation design codes, evaluation of existing ... transverse plank deck the span of the deck is.

  7. Self-Consolidating Concrete for Prestressed Bridge Girders

    Science.gov (United States)

    2017-07-01

    This document reports the findings of a research project designed to better understand material and structural performance of prestressed bridge girders made with Self-Consolidating Concrete (SCC) from Wisconsin. SCC has high potential to be used for...

  8. Looking Beyond the Bridge

    DEFF Research Database (Denmark)

    Jahn, Elke; Rosholm, Michael

    We perform a comprehensive analysis of the stepping-stone effect of temporary agency employment on unemployed workers. Using the timing-of-events approach, we not only investigate whether agency employment is a bridge into regular employment but also analyze its effect on post-unemployment wages...

  9. Bridging a Cultural Gap

    Science.gov (United States)

    Leviatan, Talma

    2008-01-01

    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…

  10. Quantum Bidding in Bridge

    Science.gov (United States)

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

    2014-04-01

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

  11. Bridging the Transition Gap

    Science.gov (United States)

    2013-05-23

    period and provide recommendations to guide future research and policy development. 4 DEFINING THE TRANSITIONAL SECURITY GAP There have been...BRIDGING THE TRANSITION GAP A Monograph by MAJ J.D. Hansen United States Army School of Advanced Military Studies United States Army...suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704

  12. Bridging the Gaps.

    Science.gov (United States)

    Netzer, Greg

    1995-01-01

    Discusses a model water quality monitoring project, Project Bridge, established to train minority girls about to enter eighth grade in scientific procedures followed by hands-on experimentation. Students spent a week monitoring water in an urban stream and analyzing results. (LZ)

  13. Bridging the Gap

    DEFF Research Database (Denmark)

    Dahlberg, Rasmus

    2016-01-01

    The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresu...... in its final report to the Danish and Swedish transport authorities while drawing upon experiences from two recent comparable cases of infrastructure disruptions: The Champlain Bridge (2009) and the Forth Road Bridge (2015).......The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresund...... Tunnel, approximately 25,000 of them critical to the regional work market. Even though the risk analysis states that the likelihood of a long-term closure (100C days) is very low Danish and Swedish transport authorities have demanded that the infrastructure operator conducts a survey of the preparedness...

  14. Revised Rules for Concrete Bridges

    DEFF Research Database (Denmark)

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

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

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

    Directory of Open Access Journals (Sweden)

    Lipeng An

    2016-07-01

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

  16. Flood Control Minnesota River, Minnesota, Mankato-North Mankato-Le Hillier. Design Memorandum Number 8. Part I. Location Study and Draft Supplement II to the Final Environmental Impact Statement for Bridge Relocations. Main Street, Trunk Highways 60 Bridge over the Minnesota River between Mankato and North Mankato.

    Science.gov (United States)

    1981-06-01

    topography or in rugged terrain, majur road overcrossings may be attainable only by a forced alinement and rolling gradeline. Where there otherwise...Wisconsin PCB Interagency Task Force in 1976 indicated that the game fish in the Minnesota River near Mankato have higher polychlorinated biphenyl (PCB...Highway River Structures Job Sum 5,920,000.00 TOTAL BRIDGES $6,875,000.00 TOTAL ROADWAY AND BRIDGES $11,674,000.00 Force Accounts CNW T. Co. Track Removal

  17. Earthquake Resilient Bridge Columns Utilizing Damage Resistant Hybrid Fiber Reinforced Concrete

    OpenAIRE

    Trono, William Dean

    2014-01-01

    Modern reinforced concrete bridges are designed to avoid collapse and to prevent loss of life during earthquakes. To meet these objectives, bridge columns are typically detailed to form ductile plastic hinges when large displacements occur. California seismic design criteria acknowledges that damage such as concrete cover spalling and reinforcing bar yielding may occur in columns during a design-level earthquake. The seismic resilience of bridge columns can be improved through the use of a da...

  18. Bridge scour countermeasure assessments at select bridges in the United States, 2014–16

    Science.gov (United States)

    Dudunake, Taylor J.; Huizinga, Richard J.; Fosness, Ryan L.

    2017-05-23

    In 2009, the Federal Highway Administration published Hydraulic Engineering Circular No. 23 (HEC-23) to provide specific design and implementation guidelines for bridge scour and stream instability countermeasures. However, the effectiveness of countermeasures implemented over the past decade following those guidelines has not been evaluated. Therefore, in 2013, the U.S. Geological Survey, in cooperation with the Federal Highway Administration, began a study to assess the current condition of bridge-scour countermeasures at selected sites to evaluate their effectiveness. Bridge-scour countermeasures were assessed during 2014-2016. Site assessments included reviewing countermeasure design plans, summarizing the peak and daily streamflow history, and assessments at each site. Each site survey included a photo log summary, field form, and topographic and bathymetric geospatial data and metadata. This report documents the study area and site-selection criteria, explains the survey methods used to evaluate the condition of countermeasures, and presents the complete documentation for each countermeasure assessment.

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

    DEFF Research Database (Denmark)

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

    This paper presents an ambient vibration study of the Vestvej Bridge. The bridge is a typically Danish two-span concrete bridge which crosses a highway. The purpose of the study is to perform a pre-investigation of the dynamic behavior to obtain information for the design of a demonstration project...... concerning application of vibration based inspection of bridges. The data analysis process of ambient vribration testing of bridges has traditionally been based on auto and cross spectral densities estimated using an FFT algorithm. In the pre-analysis state the spectral densities are all averaged to obtain...... measurements might have a low signal to noise ratio. Thus, it might be difficult clearly to identify physical modes from the spectral densities. The Random Decrement (RD) technique is another method to perform the data analysis process in the time domain only. It is basically a very simple and very easily...

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

    DEFF Research Database (Denmark)

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

    1998-01-01

    This paper presents an ambient vibration study of the Vestvej Bridge. The bridge is a typically Danish two-span concrete bridge which crosses a highway. The purpose of the study is to perform a pre-investigation of the dynamic behavior to obtain information for the design of a demonstration project...... concerning application of vibration based inspection of bridges. The data analysis process of ambient vribration testing of bridges has traditionally been based on auto and cross spectral densities estimated using an FFT algorithm. In the pre-analysis state the spectral densities are all averaged to obtain...... measurements might have a low signal to noise ratio. Thus, it might be difficult clearly to identify physical modes from the spectral densities. The Random Decrement (RD) technique is another method to perform the data analysis process in the time domain only. It is basically a very simple and very easily...

  1. Simulation of multivariate diffusion bridges

    DEFF Research Database (Denmark)

    Bladt, Mogens; Finch, Samuel; Sørensen, Michael

    We propose simple methods for multivariate diffusion bridge simulation, which plays a fundamental role in simulation-based likelihood and Bayesian inference for stochastic differential equations. By a novel application of classical coupling methods, the new approach generalizes a previously...... proposed simulation method for one-dimensional bridges to the mulit-variate setting. First a method of simulating approzimate, but often very accurate, diffusion bridges is proposed. These approximate bridges are used as proposal for easily implementable MCMC algorithms that produce exact diffusion bridges...

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

    CERN Document Server

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

    2006-01-01

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

  3. Electrical Actuation Technology Bridging

    Science.gov (United States)

    Hammond, Monica (Compiler); Sharkey, John (Compiler)

    1993-01-01

    This document contains the proceedings of the NASA Electrical Actuation Technology Bridging (ELA-TB) Workshop held in Huntsville, Alabama, September 29-October 1, 1992. The workshop was sponsored by the NASA Office of Space Systems Development and Marshall Space Flight Center (MSFC). The workshop addressed key technologies bridging the entire field of electrical actuation including systems methodology, control electronics, power source systems, reliability, maintainability, and vehicle health management with special emphasis on thrust vector control (TVC) applications on NASA launch vehicles. Speakers were drawn primarily from industry with participation from universities and government. In addition, prototype hardware demonstrations were held at the MSFC Propulsion Laboratory each afternoon. Splinter sessions held on the final day afforded the opportunity to discuss key issues and to provide overall recommendations. Presentations are included in this document.

  4. A Bridge to Active Learning: A Summer Bridge Program Helps Students Maximize Their Active-Learning Experiences and the Active-Learning Experiences of Others

    Science.gov (United States)

    Cooper, Katelyn M.; Ashley, Michael; Brownell, Sara E.

    2017-01-01

    National calls to improve student academic success in college have sparked the development of bridge programs designed to help students transition from high school to college. We designed a 2-week Summer Bridge program that taught introductory biology content in an active-learning way. Through a set of exploratory interviews, we unexpectedly…

  5. BALKANS: Building bridges

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    At a time when upheaval and political unrest in some Balkan countries gives cause for concern, it is good to know that physics, once again, is building bridges between nations. The new international mobility in the region was marked by a major activity of the Balkan Physical Union - the first Balkan School of Physics, held on the banks of the Bosphorus during the first two weeks of September

  6. Impact Coefficient Analysis of Long-Span Railway Cable-Stayed Bridge Based on Coupled Vehicle-Bridge Vibration

    Directory of Open Access Journals (Sweden)

    Yongle Li

    2015-01-01

    Full Text Available Compared with medium and small span bridges, very limited attention has been paid on the research of the impact coefficient of long-span railway bridges. To estimate the impact effects of long-span railway bridges subjected to moving vehicles, a real long-span railway cable-stayed bridge is regarded as the research object in this study, and a coupled model of vehicle-bridge system is established. The track irregularities are taken as the system excitation and the dynamic responses of the vehicle-bridge system are calculated. The impact effects on main girder, stayed cable, bearings, and bridge tower are discussed at various vehicle speeds. The results show that different components of the long-span railway cable-stayed bridge have different impact coefficients. Even for each part, the impact coefficient is also different at different local positions. It reveals that the impact coefficients in the actual situation may have significant differences with the related code clauses in the present design codes.

  7. Estimation of Curvature Changes for Steel-Concrete Composite Bridge Using Fiber Bragg Grating Sensors

    OpenAIRE

    Kang, Donghoon; Chung, Wonseok

    2013-01-01

    This study is focused on the verification of the key idea of a newly developed steel-concrete composite bridge. The key idea of the proposed bridge is to reduce the design moment by applying vertical prestressing force to steel girders, so that a moment distribution of a continuous span bridge is formed in a simple span bridge. For the verification of the key technology, curvature changes of the bridge should be monitored sequentially at every construction stage. A pair of multiplexed FBG sen...

  8. On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments

    Science.gov (United States)

    Prasai, Binay; Wilson, A. R.; Wiley, B. J.; Ren, Y.; Petkov, Valeri

    2015-10-01

    The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.The extent to which current theoretical modeling alone can

  9. Removing bridge barriers stimulates suicides: an unfortunate natural experiment.

    Science.gov (United States)

    Beautrais, Annette L; Gibb, Sheree J; Fergusson, David M; Horwood, L John; Larkin, Gregory Luke

    2009-06-01

    Safety barriers to prevent suicide by jumping were removed from Grafton Bridge in Auckland, New Zealand, in 1996 after having been in place for 60 years. This study compared the number of suicides due to jumping from the bridge after the reinstallation of safety barriers in 2003. National mortality data for suicide deaths were compared for three time periods: 1991-1995 (old barrier in place); 1997-2002 (no barriers in place); 2003-2006 (after barriers were reinstated). Removal of barriers was followed by a fivefold increase in the number and rate of suicides from the bridge. These increases led to a decision to reinstall safety barriers. Since the reinstallation of barriers, of an improved design, in 2003, there have been no suicides from the bridge. This natural experiment, using a powerful a-b-a (reversal) design, shows that safety barriers are effective in preventing suicide: their removal increases suicides; their reinstatement prevents suicides.

  10. A study on seismic behavior of pile foundations of bridge abutment on liquefiable ground through shaking table tests

    Science.gov (United States)

    Nakata, Mitsuhiko; Tanimoto, Shunsuke; Ishida, Shuichi; Ohsumi, Michio; Hoshikuma, Jun-ichi

    2017-10-01

    There is risk of bridge foundations to be damaged by liquefaction-induced lateral spreading of ground. Once bridge foundations have been damaged, it takes a lot of time for restoration. Therefore, it is important to assess the seismic behavior of the foundations on liquefiable ground appropriately. In this study, shaking table tests of models on a scale of 1/10 were conducted at the large scale shaking table in Public Works Research Institute, Japan, to investigate the seismic behavior of pile-supported bridge abutment on liquefiable ground. The shaking table tests were conducted for three types of model. Two are models of existing bridge which was built without design for liquefaction and the other is a model of bridge which was designed based on the current Japanese design specifications for highway bridges. As a result, the bending strains of piles of the abutment which were designed based on the current design specifications were less than those of the existing bridge.

  11. Multiobjective Optimal Control of Longitudinal Seismic Response of a Multitower Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Geng Fangfang

    2016-01-01

    Full Text Available The dynamic behavior of a multitower cable-stayed bridge with the application of partially longitudinal constraint system using viscous fluid dampers under real earthquake ground motions is presented. The study is based on the dynamic finite element model of the Jiashao Bridge, a six-tower cable-stayed bridge in China. The prime aim of the study is to investigate the effectiveness of viscous fluid dampers on the longitudinal seismic responses of the bridge and put forth a multiobjective optimization design method to determine the optimized parameters of the viscous fluid dampers. The results of the investigations show that the control objective of the multitower cable-stayed bridge with the partially longitudinal constraint system is to yield maximum reductions in the base forces of bridge towers longitudinally restricted with the bridge deck, with slight increases in the base forces of bridge towers longitudinally unrestricted with the bridge deck. To this end, a multiobjective optimization design method that uses a nondominating sort genetic algorithm II (NSGA-II is used to optimize parameters of the viscous fluid dampers. The effectiveness of the proposed optimization design method is demonstrated for the multitower cable-stayed bridge with the partially longitudinal constraint system, which reveals that a design engineer can choose a set of proper parameters of the viscous fluid dampers from Pareto optimal fronts that can satisfy the desired performance requirements.

  12. Construction control of cable-stayed bridges

    OpenAIRE

    Lozano Galant, José Antonio

    2013-01-01

    Premi extraordinari doctorat curs 2012-2013, àmbit d’Enginyeria Civil This work presents a study of the simulation of cable-stayed bridges built on temporary supports focused on their response during construction and in service. To simulate the behavior during construction, a set of four different algorithms has been developed to deal with initial design (Backward Algorithm), updating the tensioning process when deviations on site are measured (Forward Algorithm), optimization processes (D...

  13. Morphological aspects of myocardial bridges.

    Science.gov (United States)

    Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

    2013-11-01

    Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

  14. MODERN ASPECTS OF BRIDGES MONITORING

    Directory of Open Access Journals (Sweden)

    M. I. Kazakevych

    2007-12-01

    Full Text Available The major concepts of the elaboration and realization of the bridge construction monitoring systemic approach are presented in this paper. The main peculiarity of the bridge monitoring modern aspect is pointed out here, namely, the transition from the demands of providing the reliability to the demands of providing the whole complex of the structure consumer qualities. The criteria of diagnostics of the bridge exploitation reliability as the fundamental aim of monitoring are formulated here.

  15. Teknologvurdering, Broer og Brugere (Technology Assessment: Bridges and Users)

    DEFF Research Database (Denmark)

    Munch, Birgitte

    A critique of the scientific approaches grounding Danish technology assessments for beingnon-reflexive upon the consequences of its biased treatment of who and how some countsas ‘users'. Implications and new approaches are outlined in a story of engineering designers conceptualization of ships pa...... passing the Great Belt - the ‘sailing users' - during the constructionof the suspension bridge across the east channel. A story about 'How the Great BeltEast bridge main span got the length of 1624m....

  16. Structural health monitoring of bridge cables : An overview

    OpenAIRE

    DRISSI HABTI, Monssef; BETTI, Raimondo; YANEV, Bojidar

    2009-01-01

    Bridges are critical components of the civil infrastructure and are normally designed for a long life span. The life span of suspension bridges depends on the health of their cables, which, in turn, is a function of many factors. Therefore, continuous health monitoring (SHM) and regular condition assessment of cables is highly desirable. In this article, some SHM procedures based on direct, indirect non-destructive techniques NDT, and vibration theory are presented.

  17. Bridge Crossing Simulator

    Science.gov (United States)

    2014-10-07

    is counted as. Per the TDTC, a test bridge with longitudinal and/or lateral symmetry under non- eccentric loading can be considered as 1, 2, or 4...Level Run036 3 MLC70T (tracked) BA Run046 6 AB Run055 9 AB Run060 9 BA Run064 12 BA Run071 15 AB Run155 3 MLC96W ( wheeled ) AB...Run331 9 AB Run359 15 AB Run430 12 MLC96W ( wheeled ) BA Run434 12 AB Run447 3 BA Bank Condition: Side Slope, Even Strain Channels High

  18. A Simple and Universal Resistive-Bridge Sensors Interface

    Directory of Open Access Journals (Sweden)

    Sergey Y. YURISH

    2011-02-01

    Full Text Available Resistive-bridge sensors are widely used in various sensor systems. There are many sensor signal conditioners from different manufacturers for such sensing elements. However, no one existing on the modern market integrated converter for resistive bridge sensors can work with both: resistive-bridge sensing elements and resistive-to-frequency and -duty-cycle converters’ outputs. A proposed and described in the article universal interface for resistive-bridge sensing elements and bridge-output-to-frequency and/or duty cycle converters based on the designed Universal Sensors and Transducers Interface (USTI integrated. It is based on a simple, cost effective three-point measuring technique and does not require any additional active components. The USTI IC is realized in a standard CMOS technology. The active supply current at operating voltage +4.5 V and clock frequency 20 MHz is not more than 9.5 mA This paper reports experimental results with a strain gauges bridge emulator and differential pressure resistive bridge sensor SX30GD2.

  19. An overheight vehicle bridge collision monitoring system using piezoelectric transducers

    Science.gov (United States)

    Song, G.; Olmi, C.; Gu, H.

    2007-04-01

    With increasing traffic volume follows an increase in the number of overheight truck collisions with highway bridges. The detection of collision impact and evaluation of the impact level is a critical issue in the maintenance of a concrete bridge. In this paper, an overheight collision detection and evaluation system is developed for concrete bridge girders using piezoelectric transducers. An electric circuit is designed to detect the impact and to activate a digital camera to take photos of the offending truck. Impact tests and a health monitoring test were conducted on a model concrete bridge girder by using three piezoelectric transducers embedded before casting. From the experimental data of the impact test, it can be seen that there is a linear relation between the output of sensor energy and the impact energy. The health monitoring results show that the proposed damage index indicates the level of damage inside the model concrete bridge girder. The proposed overheight truck-bridge collision detection and evaluation system has the potential to be applied to the safety monitoring of highway bridges.

  20. Expected damages of retrofitted bridges with RC jacketing

    Science.gov (United States)

    Montes, O.; Jara, J. M.; Jara, M.; Olmos, B. A.

    2015-07-01

    The bridge infrastructure in many countries of the world consists of medium span length structures built several decades ago and designed for very low seismic forces. Many of them are reinforced concrete structures that according to the current code regulations have to be rehabilitated to increase their seismic capacity. One way to reduce the vulnerability of the bridges is by using retrofitting techniques that increase the strength of the structure or by incorporating devices to reduce the seismic demand. One of the most common retrofit techniques of the bridges substructures is the use of RC jacketing; this research assesses the expected damages of seismically deficient medium length highway bridges retrofitted with reinforced concrete jacketing, by conducting a parametric study. We select a suite of twenty accelerograms of subduction earthquakes recorded close to the Pacific Coast in Mexico. The original structures consist of five 30 m span simple supported bridges with five pier heights of 5 m, 10 m, 15 m 20 and 25 m and the analyses include three different jacket thickness and three steel ratios. The bridges were subjected to the seismic records and non-linear time history analyses were carried out by using the OpenSEEs Plataform. Results allow selecting the reinforced concrete jacketing that better improves the expected seismic behavior of the bridge models.

  1. Expected damages of retrofitted bridges with RC jacketing

    International Nuclear Information System (INIS)

    Montes, O; Jara, J M; Jara, M; Olmos, B A

    2015-01-01

    The bridge infrastructure in many countries of the world consists of medium span length structures built several decades ago and designed for very low seismic forces. Many of them are reinforced concrete structures that according to the current code regulations have to be rehabilitated to increase their seismic capacity. One way to reduce the vulnerability of the bridges is by using retrofitting techniques that increase the strength of the structure or by incorporating devices to reduce the seismic demand. One of the most common retrofit techniques of the bridges substructures is the use of RC jacketing; this research assesses the expected damages of seismically deficient medium length highway bridges retrofitted with reinforced concrete jacketing, by conducting a parametric study. We select a suite of twenty accelerograms of subduction earthquakes recorded close to the Pacific Coast in Mexico. The original structures consist of five 30 m span simple supported bridges with five pier heights of 5 m, 10 m, 15 m 20 and 25 m and the analyses include three different jacket thickness and three steel ratios. The bridges were subjected to the seismic records and non-linear time history analyses were carried out by using the OpenSEEs Plataform. Results allow selecting the reinforced concrete jacketing that better improves the expected seismic behavior of the bridge models. (paper)

  2. 3 long bridges of dream were realized Opening of West Seto Motorway; Yume no 3 kakyo ga jitsugen/nishiseto jidoshado haitsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-10

    Onomichi-Imabari route/Setouchi Simanami Thruway, which adorned the finish of Honshu-Shikoku projects was completed on 1st, May. With this completion, 3 long bridges of dream were completely realized, following to Kojima-Sakaide (1988) and Kobe-Naruto (1998). This time, 5 bridges of this Motorway, the world's longest cable stayed bridge Tatara Long Bridge, world's first 3 continuous suspension bridge Kurushima Strait No.1{approx}No.3 bridge and New Onomichi Long Bridge, were opened. 10 bridges including 5 bridges (In-noshima Long Bridge, Ikeguchi Bridge, Omishima Bridge, Hakata/Oshima Long Bridge and Oshima Long Bridge) already under service connect 9 islands between Onomichi, Hiroshima Prefecture and Imabari, Ehime Prefecture, with a route 59 km long. Characteristic design was adopted for each bridge to demonstrate world's highest bridge erection technology of Japan. In a series of concrete construction to support superstructure of these bridges, underwater non-segregation type concrete with low hydration heat cement mainly for foundation and substructure, and high fluidity concrete for dense reinforcement layout were adopted. (translated by NEDO)

  3. 47 CFR 80.163 - Operator requirements of the Bridge-to-Bridge Act.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Operator requirements of the Bridge-to-Bridge... Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the Bridge-to-Bridge Act must have on board a radio operator who holds a restricted radiotelephone operator permit or...

  4. Field performance of timber bridges. 7, Connell Lake stress-laminated deck bridge

    Science.gov (United States)

    L. E. Hislop; M. A. Ritter

    The Connell Lake bridge was constructed in early 1991 on the Tongass National Forest, Alaska, as a demonstration bridge under the Timber Bridge Initiative. The bridge is a stress-laminated deck structure with an approximate 36-ft length and 18-ft width and is the first known stress-laminated timber bridge constructed in Alaska. Performance of the bridge was monitored...

  5. Construction Simulation Analysis of 60m-span Concrete Filled Steel Tube arch bridge

    Science.gov (United States)

    Shi, Jing Xian; Ding, Qing Hua

    2018-06-01

    The construction process of the CFST arch bridge is complicated. The construction process not only affects the structural stress in the installation, but also determines the form a bridge and internal force of the bridge. In this paper, a 60m span concrete filled steel tube tied arch bridge is taken as the background, and a three-dimensional finite element simulation model is established by using the MIDAS/Civil bridge structure analysis software. The elevation of the main arch ring, the beam stress, the forces in hanger rods and the modal frequency of the main arch during the construction stage are calculated, and the construction process is simulated and analyzed. Effectively and reasonably guide the construction and ensure that the line and force conditions of the completed bridge meet the design requirements and provides a reliable technical guarantee for the safe construction of the bridge.

  6. Evaluation of High-Speed Railway Bridges Based on a Nondestructive Monitoring System

    Directory of Open Access Journals (Sweden)

    Mosbeh R. Kaloop

    2016-01-01

    Full Text Available Recently, trains’ velocities in Korea increased more than the speed used in the design of some bridges. Accordingly, this paper demonstrates the evaluation of a railway bridge due to high-speed trains’ movement. A nondestructive monitoring system is used to assess the bridge performance under train speeds of 290, 360, 400 and 406 km/h. This system is comprised of a wireless short-term acceleration system and strain monitoring sensors attached to the bridge girder. The results of the analytical methods in time and frequency domains are presented. The following conclusions are obtained: the cross-correlation models for accelerations and strain measurements are effective to predict the performance of the bridge; the static behavior is increased with train speed developments; and the vibration, torsion, fatigue and frequency contents analyses of the bridge show that the bridge is safe under applied trains’ speeds.

  7. Estimation of Curvature Changes for Steel-Concrete Composite Bridge Using Fiber Bragg Grating Sensors

    Directory of Open Access Journals (Sweden)

    Donghoon Kang

    2013-01-01

    Full Text Available This study is focused on the verification of the key idea of a newly developed steel-concrete composite bridge. The key idea of the proposed bridge is to reduce the design moment by applying vertical prestressing force to steel girders, so that a moment distribution of a continuous span bridge is formed in a simple span bridge. For the verification of the key technology, curvature changes of the bridge should be monitored sequentially at every construction stage. A pair of multiplexed FBG sensor arrays is proposed in order to measure curvature changes in this study. They are embedded in a full-scale test bridge and measured local strains, which are finally converted to curvatures. From the result of curvature changes, it is successfully ensured that the key idea of the proposed bridge, expected theoretically, is viable.

  8. 77 FR 54652 - Draft Program Comment for Common Post-1945 Concrete and Steel Bridges

    Science.gov (United States)

    2012-09-05

    ... constructed by State transportation agencies after 1945, using reinforced concrete or steel beams and designs... proposed Program Comment: Program Comment for Common Post-1945 Concrete and Steel Bridges I. Introduction... reinforced concrete or steel beams and designs that quickly became standardized. These common bridge types...

  9. Monitoring bridge scour using fiber optic sensors.

    Science.gov (United States)

    2015-04-01

    The scouring process excavates and carries away materials from the bed and banks of streams, and from : around the piers and abutments of bridges. Scour undermines bridges and may cause bridge failures due to : structural instability. In the last 30 ...

  10. Faster bridge construction using precast substructures : brief.

    Science.gov (United States)

    2011-07-01

    Bridge replacement often requires road closures and detours that frustrate road users. It remains a key goal of Wisconsin DOT to reduce construction-related road use interruptions. This will be a challenge with bridges: Bridge inspections in 2007 ide...

  11. Lean Construction Applications for Bridge Inspection

    Science.gov (United States)

    2017-10-01

    Lean philosophy was used to analyze the efficiency of bridge inspection. Emphasis was put on identifying activities that add value to the final output, an owner approved bridge inspection report. 26 bridge inspections were shadowed. Time spent on bri...

  12. Load Distribution Factors for Composite Multicell Box Girder Bridges

    Science.gov (United States)

    Tiwari, Sanjay; Bhargava, Pradeep

    2017-12-01

    Cellular steel section composite with a concrete deck is one of the most suitable superstructures in resisting torsional and warping effects induced by highway loading. This type of structure has inherently created new design problems for engineers in estimating its load distribution when subjected to moving vehicles. Indian Codes of Practice does not provide any specific guidelines for the design of straight composite concrete deck-steel multi-cell bridges. To meet the practical requirements arising during the design process, a simple design method is needed for straight composite multi-cell bridges in the form of load distribution factors for moment and shear. This work presents load distribution characteristics of straight composite multi-cell box girder bridges under IRC trains of loads.

  13. The violin bridge as filter.

    Science.gov (United States)

    Bissinger, George

    2006-07-01

    The violin bridge filter role was investigated using modal and acoustic measurements on 12 quality-rated violins combined with systematic bridge rocking frequency f(rock) and wing mass decrements deltam on four bridges for two other violins. No isolated bridge resonances were observed; bridge motions were complex (including a "squat" mode near 0.8 kHz) except for low frequency rigid body pivot motions, all more or less resembling rocking motion at higher frequencies. A conspicuous broad peak near 2.3 kHz in bridge driving point mobility (labeled BH) was seen for good and bad violins. Similar structure was seen in averaged bridge, bridge feet, corpus mobilities and averaged radiativity. No correlation between violin quality and BH driving point, averaged corpus mobility magnitude, or radiativity was found. Increasing averaged-over-f(rock) deltam(g) from 0 to 0.12 generally increased radiativity across the spectrum. Decreasing averaged-over-deltam f(rock) from 3.6 to 2.6 kHz produced consistent decreases in radiativity between 3 and 4.2 kHz, but only few-percent decreases in BH frequency. The lowest f(rock) values were accompanied by significantly reduced radiation from the Helmholtz A0 mode near 280 Hz; this, combined with reduced high frequency output, created overall radiativity profiles quite similar to "bad" violins among the quality-rated violins.

  14. Superconductivity in small metal bridges

    International Nuclear Information System (INIS)

    Hannah, E.C.

    1975-01-01

    Josephson effects in weaklinks are discussed for low and high frequency regimes using simple perturbation techniques. It is proven that no measurement of the supercurrent dependence upon frequency above the Riedel peak frequency can be made using rf sources whose frequencies are below the Riedel peak. Thus the bulk of work done in the field on the high frequency structure of the Josephson current is shown to be invalid. Metal bridges shorter than a newly defined temperature independent length for superconductors, l/sub PHONON/, are proven to be identical in their Josephson current behavior to tunneling junctions. The BCS gap equation is generalized to include voltage gradient effects on pairs within the bridge. The oscillation frequency for long bridges (l/sub BRIDGE/ greater than l/sub PHONON/) is shown to be limited to less than 10'' Hz. An experimental test of the new voltage dependent gap is made as well as tests of the pair reforming time of bridges

  15. Online Bridge Crack Monitoring with Smart Film

    Directory of Open Access Journals (Sweden)

    Benniu Zhang

    2013-01-01

    Full Text Available Smart film crack monitoring method, which can be used for detecting initiation, length, width, shape, location, and propagation of cracks on real bridges, is proposed. Firstly, the fabrication of the smart film is developed. Then the feasibility of the method is analyzed and verified by the mechanical sensing character of the smart film under the two conditions of normal strain and crack initiation. Meanwhile, the coupling interference between parallel enameled wires of the smart film is discussed, and then low-frequency detecting signal and the custom communication protocol are used to decrease interference. On this basis, crack monitoring system with smart film is designed, where the collected crack data is sent to the remote monitoring center and the cracks are simulated and recurred. Finally, the monitoring system is applied to six bridges, and the effects are discussed.

  16. Study on the Old Girders in the Widening Hollow Slab Girder Bridge

    Science.gov (United States)

    Wang, Ying; Zhang, Li Fang; Ma, Hai Yan

    2018-06-01

    Taking the bridge widening project of Shanghai-Hangzhou-Ningbo expressway widening construction project (China) as the background in this paper, the variation law of the internal force of the old bridge in the widening hollow slab girder bridge under vehicle load is studied, which is under the condition of different span lengths and different widening widths. Three different span lengths of the pre-tensioned prestressed hollow slab girder bridges are selected, the spatial finite element models of both the old bridge and the whole structure of widening bridge are established and calculated respectively by Midas/Civil software. The influences of widening and load increasing on the old bridges under the vehicle load are compared and analyzed. In addition, the authors also analyze the influences of different widening widths on the force state of old bridges under the condition of widening the same number of lane. Moreover , the effects on the old bridges that are caused by the uneven foundation settlement of widening bridge structure are also studied in this paper. This paper can provide some references for widening design of hollow slab bridges.

  17. Structural health monitoring results on Tsing Ma, Kap Shui Mun, and Ting Kau bridges

    Science.gov (United States)

    Wong, Kai-yuen; Chan, Wai-Yee K.; Man, King-Leung; Mak, W. L. N.; Lau, C. K.

    2000-06-01

    A structural health monitoring system has been installed in the cable-supported bridges located in the West of Hong Kong, i.e. the Tsing Ma Control Area. These cable-supported bridges are the Tsing Ma (Suspension) Bridge, the Kap Shu Mun (Cable- Stayed) Bridge and the Ting Kau (Cable-Stayed Bridge) Bridge. The monitoring system of Tsing Ma Bridge and Kap Shui Mun Bridge has been operated since May 1997, whereas the monitoring system of Ting Kau Bridge has been operated since November 1998. In past years, data received from the monitoring systems have been processed, and analyzed and archived. This paper first briefly outlines the operation of the data processing and analysis, and then presents: (1) the load effects monitoring results such as wind, temperature and traffic (highway and railway), and (2) the bridge responses monitoring results such as displacements, stresses/strains, accelerations and cables forces. Comparisons between monitoring results and design parameters and assumptions for the cable-supported bridges are also presented.

  18. Study on seismic behaviour of integral concrete bridges with different skew angles through fragility curves

    Directory of Open Access Journals (Sweden)

    Mahmoud Reza ُُShiravand

    2017-12-01

    Full Text Available Bridges are key elements in urban transportation system and should be designed to sustain earthquake induced damages to be utilized after earthquake. Extensive damages during last earthquakes highlighted the importance of seismic assessment and damage estimation of bridges. Skewness is one of the primary parameters effects on seismic behavior of bridges. Skew bridges are defined as bridges with skew angle piers and abutments. In these bridges, the piers have some degrees of skewness due to construction restrictions, such as those caused by crossing a waterway, railway line or road. This paper aims to investigate seismic behavior of skew concrete bridges using damage criteria and estimate probability of piers damage with fragility curves. To this end, three types of concrete bridges with two, three and four spans and varying skew angles of 00 ,100, 200 and 300 are modeled with finite element software. Seismic responses of bridge piers under 10 earthquake ground motion records are calculated using incremental dynamic analysis. Following, damage criteria proposed by Mackie and Stojadinovic are used to define damage limits of bridge piers in four damage states of slight, moderate, extensive and complete and bridge fragility curves are developed. The results show that increasing skew angles increases the probability of damage occurrence, particularly in extensive and complete damage states.

  19. Research of diagnosis sensors fault based on correlation analysis of the bridge structural health monitoring system

    Science.gov (United States)

    Hu, Shunren; Chen, Weimin; Liu, Lin; Gao, Xiaoxia

    2010-03-01

    Bridge structural health monitoring system is a typical multi-sensor measurement system due to the multi-parameters of bridge structure collected from the monitoring sites on the river-spanning bridges. Bridge structure monitored by multi-sensors is an entity, when subjected to external action; there will be different performances to different bridge structure parameters. Therefore, the data acquired by each sensor should exist countless correlation relation. However, complexity of the correlation relation is decided by complexity of bridge structure. Traditionally correlation analysis among monitoring sites is mainly considered from physical locations. unfortunately, this method is so simple that it cannot describe the correlation in detail. The paper analyzes the correlation among the bridge monitoring sites according to the bridge structural data, defines the correlation of bridge monitoring sites and describes its several forms, then integrating the correlative theory of data mining and signal system to establish the correlation model to describe the correlation among the bridge monitoring sites quantificationally. Finally, The Chongqing Mashangxi Yangtze river bridge health measurement system is regards as research object to diagnosis sensors fault, and simulation results verify the effectiveness of the designed method and theoretical discussions.

  20. A probabilistic computational framework for bridge network optimal maintenance scheduling

    International Nuclear Information System (INIS)

    Bocchini, Paolo; Frangopol, Dan M.

    2011-01-01

    This paper presents a probabilistic computational framework for the Pareto optimization of the preventive maintenance applications to bridges of a highway transportation network. The bridge characteristics are represented by their uncertain reliability index profiles. The in/out of service states of the bridges are simulated taking into account their correlation structure. Multi-objective Genetic Algorithms have been chosen as numerical tool for the solution of the optimization problem. The design variables of the optimization are the preventive maintenance schedules of all the bridges of the network. The two conflicting objectives are the minimization of the total present maintenance cost and the maximization of the network performance indicator. The final result is the Pareto front of optimal solutions among which the managers should chose, depending on engineering and economical factors. A numerical example illustrates the application of the proposed approach.

  1. Bridge SHM system based on fiber optical sensing technology

    Science.gov (United States)

    Li, Sheng; Fan, Dian; Fu, Jiang-hua; Huang, Xing; Jiang, De-sheng

    2015-09-01

    The latest progress of our lab in recent 10 years on the area of bridge structural health monitoring (SHM) based on optical fiber sensing technology is introduced. Firstly, in the part of sensing technology, optical fiber force test-ring, optical fiber vibration sensor, optical fiber smart cable, optical fiber prestressing loss monitoring method and optical fiber continuous curve mode inspection system are developed, which not only rich the sensor types, but also provides new monitoring means that are needed for the bridge health monitoring system. Secondly, in the optical fiber sensing network and computer system platform, the monitoring system architecture model is designed to effectively meet the integration scale and effect requirement of engineering application, especially the bridge expert system proposed integration of sensing information and informatization manual inspection to realize the mode of multi index intelligence and practical monitoring, diagnosis and evaluation. Finally, the Jingyue bridge monitoring system as the representative, the research on the technology of engineering applications are given.

  2. Criteria for assessment of bridge aesthetic and visual quality

    Science.gov (United States)

    Rozentale, I.; Paeglitis, A.

    2017-10-01

    The bridge designers should find an ideal balance between structure, economy, buildability, aesthetics, durability and harmony with industrial or natural landscape. During the last years, the society has adopted documents providing procedures for evaluation of the impact of the structural appearance on surrounding landscape. The European Landscape Convention defines the landscape as an area perceived by people, whose character is the result of the action and interaction of natural and/or human factors. The Convention indicates the methods for clear and objective assessment of the landscape’s visual qualities. The esthetical qualities of bridge structures, appearance and attraction should satisfy not only the technicians - engineers and architects, but mostly the surrounding population. Each of these groups has a different perception of esthetical qualities of structure. Many authors have used different methods and criteria for assessment of bridge aesthetics. The aim of this paper is to provide an overview of the bridge aesthetic and visual quality assessment methods and criteria.

  3. Reserves in load capacity assessment of existing bridges

    Science.gov (United States)

    Žitný, Jan; Ryjáček, Pavel

    2017-09-01

    High percentage of all railway bridges in the Czech Republic is made of structural steel. Majority of these bridges is designed according to historical codes and according to the deterioration, they have to be assessed if they satisfy the needs of modern railway traffic. The load capacity assessment of existing bridges according to Eurocodes is however often too conservative and especially, braking and acceleration forces cause huge problems to structural elements of the bridge superstructure. The aim of this paper is to review the different approaches for the determination of braking and acceleration forces. Both, current and historical theoretical models and in-situ measurements are considered. The research of several local European state norms superior to Eurocode for assessment of existing railway bridges shows the big diversity of used local approaches and the conservativeness of Eurocode. This paper should also work as an overview for designers dealing with load capacity assessment, revealing the reserves for existing bridges. Based on these different approaches, theoretical models and data obtained from the measurements, the method for determination of braking and acceleration forces on the basis of real traffic data should be proposed.

  4. Real-time seismic monitoring of the integrated cape girardeau bridge array and recorded earthquake response

    Science.gov (United States)

    Celebi, M.

    2006-01-01

    This paper introduces the state of the art, real-time and broad-band seismic monitoring network implemented for the 1206 m [3956 ft] long, cable-stayed Bill Emerson Memorial Bridge in Cape Girardeau (MO), a new Mississippi River crossing, approximately 80 km from the epicentral region of the 1811-1812 New Madrid earthquakes. The bridge was designed for a strong earthquake (magnitude 7.5 or greater) during the design life of the bridge. The monitoring network comprises a total of 84 channels of accelerometers deployed on the superstructure, pier foundations and at surface and downhole free-field arrays of the bridge. The paper also presents the high quality response data obtained from the network. Such data is aimed to be used by the owner, researchers and engineers to assess the performance of the bridge, to check design parameters, including the comparison of dynamic characteristics with actual response, and to better design future similar bridges. Preliminary analyses of ambient and low amplitude small earthquake data reveal specific response characteristics of the bridge and the free-field. There is evidence of coherent tower, cable, deck interaction that sometimes results in amplified ambient motions. Motions at the lowest tri-axial downhole accelerometers on both MO and IL sides are practically free from any feedback from the bridge. Motions at the mid-level and surface downhole accelerometers are influenced significantly by feedback due to amplified ambient motions of the bridge. Copyright ASCE 2006.

  5. Bridging the Evaluation Gap

    Directory of Open Access Journals (Sweden)

    Paul Wouters

    2017-02-01

    Full Text Available Paul Wouters’ essay is concerned with bridging the gap between what we value in our academic work and how we are assessed in formal evaluation exercises. He reflects on the recent evaluation of his own center, and reminds us that it is productive to see evaluations not as the (obviously impossible attempt to produce a true representation of past work, but rather as the exploration and performance of “who one wants to be.” Reflecting on why STS should do more than just play along to survive in the indicator game, he suggests that our field should contribute to changing its very rules. In this endeavor, the attitude and sensibilities developed in our field may be more important than any specific theoretical concepts or methodologies.

  6. Linguistic Barriers and Bridges

    DEFF Research Database (Denmark)

    Thuesen, Frederik

    2016-01-01

    The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... groups, the sociology of work needs to develop a better understanding of the way in which linguistic diversity influences the formation of social capital, i.e. resources such as the trust and reciprocity inherent in social relations in such workplaces. Drawing on theories about intergroup contact...... and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst...

  7. Majorana entanglement bridge

    Science.gov (United States)

    Plugge, Stephan; Zazunov, Alex; Sodano, Pasquale; Egger, Reinhold

    2015-06-01

    We study the concurrence of entanglement between two quantum dots in contact to Majorana bound states on a floating superconducting island. The distance between the Majorana states, the charging energy of the island, and the average island charge are shown to be decisive parameters for the efficiency of entanglement generation. We find that long-range entanglement with basically distance-independent concurrence is possible over wide parameter regions, where the proposed setup realizes a "Majorana entanglement bridge." We also study the time-dependent concurrence obtained after one of the tunnel couplings is suddenly switched on, which reveals the time scales for generating entanglement. Accurate analytical expressions for the concurrence are derived both for the static and the time-dependent cases. Our results indicate that entanglement formation in interacting Majorana devices can be fully understood in terms of an interplay of elastic cotunneling (also referred to as "teleportation") and crossed Andreev reflection processes.

  8. Electrothermally Tunable Bridge Resonator

    KAUST Repository

    Hajjaj, Amal Z.; Alcheikh, Nouha; Ramini, Abdallah; Hafiz, Md Abdullah Al; Younis, Mohammad I.

    2016-01-01

    This paper demonstrates experimentally, theoretically, and numerically a wide-range tunability of an in-plane clamped-clamped microbeam, bridge, and resonator compressed by a force due to electrothermal actuation. We demonstrate that a single resonator can be operated at a wide range of frequencies. The microbeam is actuated electrothermally, by passing a DC current through it. We show that when increasing the electrothermal voltage, the compressive stress inside the microbeam increases, which leads eventually to its buckling. Before buckling, the fundamental frequency decreases until it drops to very low values, almost to zero. After buckling, the fundamental frequency increases, which is shown to be as high as twice the original resonance frequency. Analytical results based on the Galerkin discretization of the Euler Bernoulli beam theory are generated and compared to the experimental data and to simulation results of a multi-physics finite-element model. A good agreement is found among all the results.

  9. Electrothermally Tunable Bridge Resonator

    KAUST Repository

    Hajjaj, Amal Z.

    2016-12-05

    This paper demonstrates experimentally, theoretically, and numerically a wide-range tunability of an in-plane clamped-clamped microbeam, bridge, and resonator compressed by a force due to electrothermal actuation. We demonstrate that a single resonator can be operated at a wide range of frequencies. The microbeam is actuated electrothermally, by passing a DC current through it. We show that when increasing the electrothermal voltage, the compressive stress inside the microbeam increases, which leads eventually to its buckling. Before buckling, the fundamental frequency decreases until it drops to very low values, almost to zero. After buckling, the fundamental frequency increases, which is shown to be as high as twice the original resonance frequency. Analytical results based on the Galerkin discretization of the Euler Bernoulli beam theory are generated and compared to the experimental data and to simulation results of a multi-physics finite-element model. A good agreement is found among all the results.

  10. Cascaded resonant bridge converters

    Science.gov (United States)

    Stuart, Thomas A. (Inventor)

    1989-01-01

    A converter for converting a low voltage direct current power source to a higher voltage, high frequency alternating current output for use in an electrical system where it is desired to use low weight cables and other circuit elements. The converter has a first stage series resonant (Schwarz) converter which converts the direct current power source to an alternating current by means of switching elements that are operated by a variable frequency voltage regulator, a transformer to step up the voltage of the alternating current, and a rectifier bridge to convert the alternating current to a direct current first stage output. The converter further has a second stage series resonant (Schwarz) converter which is connected in series to the first stage converter to receive its direct current output and convert it to a second stage high frequency alternating current output by means of switching elements that are operated by a fixed frequency oscillator. The voltage of the second stage output is controlled at a relatively constant value by controlling the first stage output voltage, which is accomplished by controlling the frequency of the first stage variable frequency voltage controller in response to second stage voltage. Fault tolerance in the event of a load short circuit is provided by making the operation of the first stage variable frequency voltage controller responsive to first and second stage current limiting devices. The second stage output is connected to a rectifier bridge whose output is connected to the input of the second stage to provide good regulation of output voltage wave form at low system loads.

  11. Venture Creation Programs: Bridging Entrepreneurship Education and Technology Transfer

    Science.gov (United States)

    Lackéus, Martin; Williams Middleton, Karen

    2015-01-01

    Purpose: The purpose of this paper is to explore how university-based entrepreneurship programs, incorporating real-life venture creation into educational design and delivery, can bridge the gap between entrepreneurship education and technology transfer within the university environment. Design/methodology/approach: Based on a literature review…

  12. Rational design of azide-bridged bimetallic complexes. Crystal structure and magnetic properties of Fe(III)MFe(III) (M = Ni(II) and Cu(II)) trinuclear species.

    Science.gov (United States)

    Colacio, Enrique; Costes, Jean-Pierre; Domínguez-Vera, José M; Maimoun, Ikram Ben; Suárez-Varela, José

    2005-01-28

    The first examples of azide-bridged bimetallic trinuclear complexes ([M(cyclam)][FeL(N3)(mu1,5-N3)]2) (H2L = 4,5-dichloro-1,2-bis(pyridine-2-carboxamido) benzene) have been structurally and magnetically characterized.

  13. Effect of soil–structure interaction on the reliability of reinforced concrete bridges

    OpenAIRE

    Kamel Bezih; Alaa Chateauneuf; Mahdi Kalla; Claude Bacconnet

    2015-01-01

    In the design of reinforced concrete (RC) bridges, the random and nonlinear behavior of soil may lead to insufficient reliability levels. For this reason, it is necessary to take into account the variability of soil properties which can significantly affect the bridge behavior regarding ultimate and serviceability limit states. This study investigates the failure probability for existing reinforced concrete bridges due to the effects of interaction between the soil and the structure. In this ...

  14. Wright-Fisher diffusion bridges.

    Science.gov (United States)

    Griffiths, Robert C; Jenkins, Paul A; Spanò, Dario

    2017-10-06

    The trajectory of the frequency of an allele which begins at x at time 0 and is known to have frequency z at time T can be modelled by the bridge process of the Wright-Fisher diffusion. Bridges when x=z=0 are particularly interesting because they model the trajectory of the frequency of an allele which appears at a time, then is lost by random drift or mutation after a time T. The coalescent genealogy back in time of a population in a neutral Wright-Fisher diffusion process is well understood. In this paper we obtain a new interpretation of the coalescent genealogy of the population in a bridge from a time t∈(0,T). In a bridge with allele frequencies of 0 at times 0 and T the coalescence structure is that the population coalesces in two directions from t to 0 and t to T such that there is just one lineage of the allele under consideration at times 0 and T. The genealogy in Wright-Fisher diffusion bridges with selection is more complex than in the neutral model, but still with the property of the population branching and coalescing in two directions from time t∈(0,T). The density of the frequency of an allele at time t is expressed in a way that shows coalescence in the two directions. A new algorithm for exact simulation of a neutral Wright-Fisher bridge is derived. This follows from knowing the density of the frequency in a bridge and exact simulation from the Wright-Fisher diffusion. The genealogy of the neutral Wright-Fisher bridge is also modelled by branching Pólya urns, extending a representation in a Wright-Fisher diffusion. This is a new very interesting representation that relates Wright-Fisher bridges to classical urn models in a Bayesian setting. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Bridge Creek IMW database - Bridge Creek Restoration and Monitoring Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The incised and degraded habitat of Bridge Creek is thought to be limiting a population of ESA-listed steelhead (Oncorhynchus mykiss). A logical restoration approach...

  16. Reliability Assessment of Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Middleton, C. R.

    This paper is partly based on research performed for the Highways Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: concrete bridges". It contains the details of a methodology which can be used to generate Whole Life (WL) reliability...... profiles. These WL reliability profiles may be used to establish revised rules for concrete bridges. This paper is to some extend based on Thoft-Christensen et. al. [1996], Thoft-Christensen [1996] et. al. and Thoft-Christensen [1996]....

  17. Complex Testing of the Bridges

    Directory of Open Access Journals (Sweden)

    Savić Adrijana

    2016-01-01

    Full Text Available This article describes the process of examining bridges. AB road bridge, founded on the columns by the Karpoš system and damaged due to erosive action of the river, is given as an example. The first tests of the bridge are conducted on the impact load of V 300, because of the appearance of longitudinal cracks. The results of the columns testing are presented in this paper, as well as the rehabilitation measures thus increasing the load capacity of the column.

  18. Influence of microclimate on the sustainability and reliability of weathering steel bridge

    Science.gov (United States)

    Kubzova, M.; Krivy, V.; Kreislova, K.

    2018-04-01

    Reliability and sustainability of bridge structures designed from weathering steel are influenced by the development of a sufficiently protective layer of corrosion products on its surface. The development of this protective layer is affected by several parameters such as air pollution around the bridge structure, the microclimate under the bridge, the location of surface within the bridge structure and the time of wetness. Design of structural details also significantly influences the development of the protective corrosion layer. The article deals with the results of the experimental tests carried out on the road bridge located in the city of Ostrava in the Czech Republic. The development of the protective corrosion layer on the surface of the bridge is significantly influenced by the intensive traffic under the bridge construction and the design solution of the bridge itself. Attention is focused mainly on the influence of chloride deposition on the protective function of the corrosion layer. Corrosion samples were placed on the bridge to evaluate the influence of the above-mentioned parameters. The deposition rate of chlorides spreading from the road to surfaces of the steel structure is also measured.

  19. Multi-Hazard Assessment of Scour Damaged Bridges with UAS-Based Measurements

    Science.gov (United States)

    Özcan, O.; Ozcan, O.

    2017-12-01

    Flood and stream induced scour occurring in bridge piers constructed on rivers is one of the mostly observed failure reasons in bridges. Scour induced failure risk in bridges and determination of the alterations in bridge safety under seismic effects has the ultimate importance. Thus, for the determination of bridge safety under the scour effects, the scour amount under bridge piers should be designated realistically and should be tracked and updated continuously. Hereby, the scour induced failures in bridge foundation systems will be prevented and bridge substructure design will be conducted safely. In this study, in order to measure the amount of scour in bridge load bearing system (pile foundations and pile abutments) and to attain very high definition 3 dimensional models of river flood plain for the flood analysis, unmanned aircraft system (UAS) based measurement methods were implemented. UAS based measurement systems provide new and practical approach and bring high precision and reliable solutions considering recent measurement systems. For this purpose, the reinforced concrete (RC) bridge that is located on Antalya Boğaçayı River, Turkey and that failed in 2003 due to flood-induced scour was selected as the case study. The amount of scour occurred in bridge piers and piles was determined realistically and the behavior of bridge piers under scour effects was investigated. Future flood effects and the resultant amount of scour was determined with HEC-RAS software by using digital surface models that were obtained at regular intervals using UAS for the riverbed. In the light of the attained scour measurements and expected scour after a probable flood event, the behavior of scour damaged RC bridge was investigated by pushover and time history analyses under lateral and vertical seismic loadings. In the analyses, the load and displacement capacity of bridge was observed to diminish significantly under expected scour. Thus, the deterioration in multi hazard

  20. Numerical investigation into thermal load responses of steel railway bridge

    Science.gov (United States)

    Saravana Raja Mohan, K.; Sreemathy, J. R.; Saravanan, U.

    2017-07-01

    Bridge design requires consideration of the effects produced by temperature variations and the resultant thermal gradients in the structure. Temperature fluctuation leads to expansion and contraction of bridges and these movements are taken care by providing expansion joints and bearings. Free movements of a member can be restrained by imposing certain boundary condition but at the same time considerable allowances should be made for the stresses resulting from this restrained condition since the additional deformations and stresses produced may affect the ultimate and serviceability limit states of the structure. If the reaction force generated by the restraints is very large, then its omission can lead to unsafe design. The principal objective of this research is to study the effects of temperature variation on stresses and deflection in a steel railway bridge. A numerical model, based on finite element analysis is presented for evaluating the thermal performance of the bridge. The selected bridge is analyzed and the temperature field distribution and the corresponding thermal stresses and strains are calculated using the finite element software ABAQUS. A thorough understanding of the thermal load responses of a structure will result in safer and dependable design practices.

  1. Learning Bridge: Curricular Integration of Didactic and Experiential Education

    Science.gov (United States)

    Arendt, Cassandra S.; Cawley, Pauline; Buhler, Amber V.; Elbarbry, Fawzy; Roberts, Sigrid C.

    2010-01-01

    Objectives To assess the impact of a program to integrate introductory pharmacy practice experiences with pharmaceutical science topics by promoting active learning, self-directed learning skills, and critical-thinking skills. Design The Learning Bridge, a curriculum program, was created to better integrate the material first-year (P1) students learned in pharmaceutical science courses into their introductory pharmacy practice experiences. Four Learning Bridge assignments required students to interact with their preceptors and answer questions relating to the pharmaceutical science material concurrently covered in their didactic courses. Assessment Surveys of students and preceptors were conducted to measure the effectiveness of the Learning Bridge process. Feedback indicated the Learning Bridge promoted students' interaction with their preceptors as well as development of active learning, self-directed learning, and critical-thinking skills. Students also indicated that the Learning Bridge assignments increased their learning, knowledge of drug information, and comprehension of relevant data in package inserts. Conclusion The Learning Bridge process integrated the didactic and experiential components of the curriculum, enhancing student learning in both areas, and offered students educational opportunities to interact more with their preceptors. PMID:20498741

  2. Special heavy plates and steel solutions for bridge building

    Science.gov (United States)

    Lehnert, Tobias

    2017-09-01

    In many European countries infrastructure, -road as well as railway infrastructure-, needs intensive investments to follow the growing demands of mobility and goods traffic. Steel or steel composite bridges offer in this context viable and very sustainable solutions. Due to its unlimited recyclability steel can in general be seen as the ideal material for such sustainable constructions, but especially when designers or fabricators exploit the nowadays available possibilities of steel industry very cost-efficient and remarkable constructions are realizable. This paper will highlight some of these newest developments in heavy plates for bridge building. For example, for small span railway bridges the so-called thick plate trough bridges have proven to be a favourable concept. Very heavy plates with single plate weights up to 42 t allow building these bridges very efficiently out of one or very few single plates. Another interesting development is the so-called longitudinally profiled plates which allow a varying plate thickness along the actual loading profile. As last point the rising entry of higher strength steels in bridge building will be discussed and it will be shown why thermomechanically rolled plates are the ideal solution for these demands.

  3. Reliability Modeling of Double Beam Bridge Crane

    Science.gov (United States)

    Han, Zhu; Tong, Yifei; Luan, Jiahui; Xiangdong, Li

    2018-05-01

    This paper briefly described the structure of double beam bridge crane and the basic parameters of double beam bridge crane are defined. According to the structure and system division of double beam bridge crane, the reliability architecture of double beam bridge crane system is proposed, and the reliability mathematical model is constructed.

  4. The stories of two bridges in Ghana

    DEFF Research Database (Denmark)

    Andreasen, Jørgen

    2004-01-01

    Public participation in bridge building was promoted by un habitat in the village of Mankrong. The neighbouring village did not participate in the construction of their bridge. The first flooding washed the second bridge down while the "participative bridge" stood up....

  5. Human Errors and Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, A. S.

    on basis of reliability profiles for bridges without human errors are extended to include bridges with human errors. The first rehabilitation distributions for bridges without and with human errors are combined into a joint first rehabilitation distribution. The methodology presented is illustrated...... for reinforced concrete bridges....

  6. Effects of Electrolyte on Floating Water Bridge

    Directory of Open Access Journals (Sweden)

    Hideo Nishiumi

    2009-01-01

    spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and NH4Cl to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte Al2O3 had no effect on the length of water bridge.

  7. Longer Lasting Bridge Deck Overlays

    Science.gov (United States)

    2018-04-01

    The objective of this report is to determine the most effective method for bridge deck overlay construction and repair by assessing current practices; examining new products and technologies; and reviewing NCHRP (National Cooperative Highway Research...

  8. Energy harvesting on highway bridges.

    Science.gov (United States)

    2011-01-01

    A concept for harvesting energy from the traffic-induced loadings on a highway bridge using piezoelectric : materials to generate electricity was explored through the prototype stage. A total of sixteen lead-zirconate : titanate (PZT) Type 5A piezoel...

  9. Research notes : listening to bridges.

    Science.gov (United States)

    2008-09-01

    The Federal Highway Administration requires owners of structurally deficient bridges to repair, replace, restrict truck loads, or conduct analysis and testing to maintain a safe highway system. Past experiments on reinforced concrete beams showed aco...

  10. Linear Cracking in Bridge Decks

    Science.gov (United States)

    2018-03-01

    Concrete cracking in bridge decks remains an important issue relative to deck durability. Cracks can allow increased penetration of chlorides, which can result in premature corrosion of the reinforcing steel and subsequent spalling of the concrete de...

  11. Performance indicators for roadway bridges

    OpenAIRE

    Strauss, A.; Vidovic, A.; Zambon, I.; Dengg, F.; Tanasic, N.; Matos, José C.

    2016-01-01

    Publicado em "Maintenance, monitoring, safety, risk and resilience of bridges and bridge networks". ISBN 978-1-138-02851-7 The performance indicators should, by its definition, allow capturing the life-cycle degradation processes affecting maintenance plans or the remaining lifetime. The qualitative or quantitative performance indicators are obtained through visual inspections, non-destructive tests or monitoring systems. After their quantification and the comparison with the resp...

  12. Bridging the Gap (BRIEFING CHARTS)

    Science.gov (United States)

    2007-03-05

    1 Defense Advanced Research Projects Agency “Bridging the Gap ” Dr. Robert F. Leheny Deputy Director Report Documentation Page Form ApprovedOMB No...comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to...4. TITLE AND SUBTITLE Bridging the Gap 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

  13. Static and Dynamic Mechanical Properties of Long-Span Cable-Stayed Bridges Using CFRP Cables

    Directory of Open Access Journals (Sweden)

    Mei Kuihua

    2017-01-01

    Full Text Available The elastic modulus and deadweight of carbon fiber-reinforced polymer (CFRP cables are different from those of steel cables. Thus, the static and dynamic behaviors of cable-stayed bridges using CFRP cables are different from those of cable-stayed bridges using steel cables. The static and dynamic performances of the two kinds of bridges with a span of 1000 m were studied using the numerical method. The effects of geometric nonlinear factors on static performance of the two kinds of cable-stayed bridges were analyzed. The live load effects and temperature effects of the two cable-stayed bridges were also analyzed. The influences of design parameters, including different structural systems, the numbers of auxiliary piers, and the space arrangement types of cable, on the dynamic performance of the cable-stayed bridge using CFRP cables were also studied. Results demonstrate that sag effect of the CFRP cable is much smaller than that of steel cable. The temperature effects of CFRP cable-stayed bridge are less than those of steel cable-stayed bridge. The vertical bending natural vibration frequency of the CFRP cable-stayed bridge is generally lower than that of steel cable-stayed bridge, whereas the torsional natural vibration frequency of the former is higher than that of the latter.

  14. Comparative Research of Extra-large-span Cable-stayed Bridge with Steel Truss Girder and Steel Box Girder

    Directory of Open Access Journals (Sweden)

    Tan Manjiang

    2015-01-01

    Full Text Available To research structural performance of extra-large-span cable-stayed bridge under different section forms, with the engineering background of a 800m main-span cable-stayed bridge with steel truss girder, the cable-stayed bridge with steel box girder is designed according to the current bridge regulations when two bridges are designed in an ultimate state of the carrying capacity, so the maximum stress and minimum stress of the stress envelope diagram are substantially the same. A comprehensive comparison is given to two types of bridge on the aspect of static force, natural vibration frequency, stability, economic performance and so on. Analysis results provide future reference for the large-span cable-stayed bridge to select between the steel truss girder and the steel box girder.

  15. Study on the structural characteristics of extradosed concrete bridges; Ekusutoradozudo kyo no kozo tokusei ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Oka, Y. [Japan Highway Public Corp., Tokyo (Japan); Kasuga, A. [Sumitomo Construction Co. Ltd., Tokyo (Japan); Yamazaki, J. [Nihon Univ., Tokyo (Japan). Coll. of Science and Engineering

    1997-03-31

    Parameters are analyzed to provide data for deciding, in the planning and designing stages, whether a cable stayed bridge or an extradosed bridge should be adopted. Comparative investigation of the vibration properties of both types of bridges is also referred to. The result of the study on the structural properties of the cable stayed road bridge and the extradosed road bridge is introduced. Based on the concept of the extradosed bridge, designers are now able to select without restraint the after load sharing rate of the diagonal members. Parameter analysis of a diagonal member reinforced 3-span continuous beam is performed. By introducing indices showing the load sharing rate of the diagonal member, the cable stayed bridge can be distinguished logically from the extradosed bridge in designing. It is found important that the height of the main tower is set to approximately 10% the length of the center span for the construction of the extradosed bridge. The vibration properties of the cable stayed bridge and the extradosed bridge of the same scale are compared. 7 refs., 18 figs., 6 tabs.

  16. Cable-stayed PC bridge with inclined main tower. Hachinohe port island bridge; Keisha shuto to yusuru 2 keikan renzoku PC shachokyo. Hachinoheko port island renrakykyo (kasho)

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, A. [Hachinohe Institute of Technology, Aomori (Japan)

    1994-09-15

    The design and construction of the inclined main bridge, which is being constructed at the mouth of the Hachinohe Harbor (in Japan), are outlined in this paper. This connecting bridge has an overall length of 265.56 m, and consists of the main bridge member of asymmetric 2 cable-stayed PC bridge and the 3 cable-stayed PC box member bridge. An asymmetric design was employed for the main bridge frame to ensure the access space for small ships passing between bridge girders, easy maintenance and service, improved economy, and excellent view. The main tower is a single-pillar reinforced concrete structure with an inclination of 15{degree} and 47 m in height. Forty-eight diagonal cables are arranged so that 12 cable trains are connected to the main tower on the right and left sides respectively, and the back-stay cable structure is used for each upper 3 cable trains to improve safety against the earthquake. The main beam is made by a prestressed concrete structure with inverse trapezoidal 3-chamber frame section. This structure is superior in increasing the safety against wind. Steel tube sheet-pile well is selected for the bridge pier base, and debris layer is selected as a support layer for the base. For the construction of the lower bridge section, sand conversion through predrilling of rubble-mound and debris layer was executed. The underwater non-separative concrete and embedded type frame are used around the bridge piers and its surrounding. For the construction of the upper bridge section, steel frames are used inside the main tower to ensure the construction precision. 7 figs.

  17. SURGERY OF SYMPTOMATIC MYOCARDIAL BRIDGING

    Directory of Open Access Journals (Sweden)

    N. Maghamipour N. Safaei

    2007-06-01

    Full Text Available Myocardial bridging with systolic compression of the left anterior descending coronary artery (LAD may be associated with myocardial ischemia. In symptomatic myocardial bridging unresponsive to medical treatment, surgical unroofing of the left LAD can be performed. Little information is available about the long-term prognosis of patients with this coronary anomaly after the surgical unroofing, so we decided to evaluate the result of this operation. A total of 26 patients underwent surgical unroofing of myocardial bridging. Patients had a myocardial bridge of at least 3 cm in length in the middle of LAD and with more than 70% compression during systole. Unroofing was performed with cardiopulmonary bypass in 16 and with off pump technique in 10 patients. In 6 patients repeat angiographies for control of myotomy were done. In one of them a nonsignificant 20% narrowing was seen. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation in 24 patients. Two patients had residual narrowing. With off pump technique, 1 patient had perforation of the right ventricle and 1 patient underwent reoperation because of incomplete unroofing during the first operation. None of the patients with cardiopulmonary bypass technique had residual chest pain or other complications. Surgical unroofing of myocardial bridging with the aid of cardiopulmonary bypass is a safe and easy procedure with low operative risk and with excellent functional results.

  18. Economic Functions Proposal of Urgency Prioritization of Investment Projects of Operated Railway Bridges

    Directory of Open Access Journals (Sweden)

    Pitoňák Martin

    2014-12-01

    Full Text Available The main objective of the article is to describe the proposals of economic functions within the prioritization of urgency investments of operated railway bridges within a comprehensive evaluation of existing bridges. The purpose of the paper is a comprehensive assessment of existing bridges and to define determinants and determinants of decision-making and designing a mechanism of decision-making procedures of prioritized infrastructure measures in the form of repairs and reconstructions of bridges resulting from the records of supervising activities based not only on technical but also economic aspects to the railway infrastructure manager.

  19. Design Argumentation in Academic Design Education

    DEFF Research Database (Denmark)

    Dalsgaard, Peter; Dindler, Christian; Fritsch, Jonas

    2013-01-01

    We explore design argumentation as a resource when teaching interaction design in a university setting. We propose that design argumentation can help bridge between practice-based design education and theoretical issues from university curricula. In this paper, we outline the idea of design...

  20. Economical bridge solutions based on innovative composite dowels and integrated abutments ecobridge

    CERN Document Server

    Băncilă, Radu

    2015-01-01

    This book is an outcome of the research project “ECOBRIDGE – Demonstration of ECOnomical BRIDGE solutions based on innovative composite dowels and integrated abutments – RFCS – CT 2010-00024”, which has been co-funded by the Research Fund for Coal and Steel (R.F.C.S.) of the European Community. The main topics of the book are the following: design of integral bridges, innovative composite dowels for the shear transmission, construction of bridges, structural analysis of bridges and monitoring. The book joins the technical experience and the contributions of the involved research partners. The technical content of all the papers is present-day in the field of the design, construction and monitoring of innovative composite bridges. The efficient design and construction improve and consolidate the market position of steel construction and steel producing industry. In addition, the advanced forms of construction are contributing to savings in material and energy consumption for the structure during prod...

  1. Study on load test of 100m cross-reinforced deck type concrete box arch bridge

    Science.gov (United States)

    Shi, Jing Xian; Cheng, Ying Jie

    2018-06-01

    Found in the routine quality inspection of highway bridge that many vertical fractures on the main beam (10mT beam) of the steel reinforced concrete arch bridge near the hydropower station. In order to grasp the bearing capacity of this bridge under working conditions with cracks, the static load and dynamic load test of box arch bridge are carried out. The Midas civil theory is calculated by using the special plate trailer - 300 as the calculation load, and the deflection and stress of the critical section are tested by the equivalent cloth load in the test vehicle. The pulsation test, obstacles and no obstacle driving test were carried out. Experimental results show that the bridge under the condition of the test loads is in safe condition, main bearing component of the strength and stiffness meet the design requirements, the crack width does not increase, in the process of loading bridge overall work performance is good.

  2. STRENGTHENING CONCRETE HOLLOW SECTION GIRDER BRIDGE USING POLYURETHANE-CEMENT MATERIAL (PART B

    Directory of Open Access Journals (Sweden)

    Haleem K. Hussain

    2018-01-01

    Full Text Available This paper presents experimental study to retrofitted reinforced concrete Hollow Section Bridge. The study was carried out on the White River Bridge structure (Bai xi da Qiao / China. The effect of retrofitting on stress and strain of beams at the critical section was studied. Evaluating the bridges girder after strengthening using new material called PolyurethaneCement material (PUC as an external material .This study present the strain and deflection before and after strengthening the bridge girders. The results has shown that the overall state of the bridge structural strengthening is in good condition. The enhancement was significant in stiffness of the bridge structure. Regarding to the results of static load test, the experimental values strain and deflection are less than theoretical values, indicating that the stiffness of the structure, overall deformation and integrity satisfy the designed and standard requirements and the working performance are in good condition, and flexure capacity has a certain surplus.

  3. Progress of optical sensor system for health monitoring of bridges at Chongqing University

    Science.gov (United States)

    Chen, W.; Fu, Y.; Zhu, Y.; Huang, S.

    2005-02-01

    With decades of research experience on optical sensors, Optoelectronic Technology Lab of Chongqing University (OTLCU) has studied on a variety of sensors system designed for practical use in health monitoring. In OTLCU, embedded and surface mounted fiber Fabry-Perot strain sensor has been developed for monitoring the local strain of both concrete and steel truss bridge. Optoelectronic deflect meter, with a group of optical level sensor in a series connected pipe, was developed for deflection monitoring and line shape monitoring of the bridges. Laser deflect meter, with a laser pointer and a sensors array, has been also developed for a dynamic deflection monitoring of the bridges. To monitoring the 2-Dimentional displacement of the bridge, a self-calibrating imaging system was developed. All these sensor systems have been applied in different bridges successfully. This paper briefly describes principle of these optical sensing systems, and also gives some representative results of the system in practical application of bridges.

  4. Nondestructive Evaluation of Railway Bridge by System Identification Using Field Vibration Measurement

    International Nuclear Information System (INIS)

    Ho, Duc Duy; Hong, Dong Soo; Kim, Jeong Tae

    2010-01-01

    This paper presents a nondestructive evaluation approach for system identification (SID) of real railway bridges using field vibration test results. First, a multi-phase SID scheme designed on the basis of eigenvalue sensitivity concept is presented. Next, the proposed multi-phase approach is evaluated from field vibration tests on a real railway bridge (Wondongcheon bridge) located in Yangsan, Korea. On the steel girder bridge, a few natural frequencies and mode shapes are experimentally measured under the ambient vibration condition. The corresponding modal parameters are numerically calculated from a three-dimensional finite element (FE) model established for the target bridge. Eigenvalue sensitivities are analyzed for potential model-updating parameters of the FE model. Then, structural subsystems are identified phase-by-phase using the proposed model-updating procedure. Based on model-updating results, a baseline model and a nondestructive evaluation of test bridge are identified

  5. Fatigue evaluation for Tsing Ma Bridge using structural health monitoring data

    Science.gov (United States)

    Chan, Hung-tin Tommy; Ko, Jan Ming; Li, Zhao-Xia

    2001-08-01

    Fatigue assessment for the Tsing Ma Bridge (TMB) are presented based on the British standard BS5400 and the real-time structural health monitoring data under railway loading. TMB, as an essential portion of transport network for the Hong Kong airport, is the longest suspension bridge in the world carrying both highway and railway traffic. The bridge design has been mainly based on BS5400. A structural health monitoring system - Wind and Structural Health Monitoring System (WASHMS) for TMB has been operated since the bridge commissioning in May 1997. In order to assess the fatigue behavior of TMB under railway loading, strain gauges were installed on the bridge deck to measure the strain-time histories as soon as the bridge is loaded by a standard railway loading due to the service of an actual train. The strain-time history data at the critical members are then used to determine the stress spectrum, of which the rainflow method recommended for railway bridges by BS5400 is applied to count cycles of stress range. Miner's law is employed to evaluate fatigue damage and remaining service life of the bridge. The evaluated results of fatigue damage and remaining service life would help us to well understand about the fatigue design of the bridge and status in fatigue accumulation.

  6. A new multiconstraint method for determining the optimal cable stresses in cable-stayed bridges.

    Science.gov (United States)

    Asgari, B; Osman, S A; Adnan, A

    2014-01-01

    Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM). The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  7. A New Multiconstraint Method for Determining the Optimal Cable Stresses in Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    B. Asgari

    2014-01-01

    Full Text Available Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM. The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  8. Service life assessment of timber highway bridges in USA climate zones

    Science.gov (United States)

    James P. Wacker; Brian K. Brashaw; Thomas G. Williamson; P. David Jones; Matthew S. Smith; Travis K. Hosteng; David L. Strahl; Lola E. Coombe; V.J. Gopu

    2014-01-01

    As engineers begin to estimate life-cycle costs and sustainable design approaches for timber bridges, there is a need for more reliable data about their durability and expected service life. This paper summarizes a comprehensive effort to assess the current condition of more than one hundred timber highway bridge superstructures throughout the United States. This...

  9. Analytical investigation of bidirectional ductile diaphragms in multi-span bridges

    Science.gov (United States)

    Wei, Xiaone; Bruneau, Michel

    2018-04-01

    In the AASHTO Guide Specifications for Seismic Bridge Design Provisions, ductile diaphragms are identified as Permissible Earthquake-Resisting Elements (EREs), designed to help resist seismic loads applied in the transverse direction of bridges. When adding longitudinal ductile diaphragms, a bidirectional ductile diaphragm system is created that can address seismic excitations acting along both the bridge's longitudinal and transverse axes. This paper investigates bidirectional ductile diaphragms with Buckling Restrained Braces (BRBs) in straight multi-span bridge with simply supported floating spans. The flexibility of the substructures in the transverse and longitudinal direction of the bridge is considered. Design procedures for the bidirectional ductile diaphragms are first proposed. An analytical model of the example bridge with bidirectional ductile diaphragms, designed based on the proposed methodology, is then built in SAP2000. Pushover and nonlinear time history analyses are performed on the bridge model, and corresponding results are presented. The effect of changing the longitudinal stiffness of the bidirectional ductile diaphragms in the end spans connecting to the abutment is also investigated, in order to better understand the impact on the bridge's dynamic performance.

  10. Monolithic Concrete vs Precast Concrete for the Construction of Bridge by Th Cantilever Method

    Directory of Open Access Journals (Sweden)

    Morlova Dumitru Daniel

    2015-07-01

    Full Text Available In the article "Monolithic Concrete vs Precast Concrete for the Construction of Bridges by the Cantilever Method", there are approached a number of issues that come out in the design and execution of prestressed concrete bridge structures using the cantilever method.

  11. Bio-based composite pedestrian bridge. Part 2: materials and production process

    NARCIS (Netherlands)

    Lepelaar, Mark; Hoogendoorn, Alwin; Blok, Rijk; Teuffel, Patrick; Kawaguchi, K.; Ohsaki, M.; Takeuchi, T.

    2016-01-01

    The Bio-based composite bridge is a 3TU project which aims to design and realize a 14m span pedestrian bridge made from fibre-reinforced polymers (FRP) and which is introduced in part 1 of this paper. Part 2 will focus on various studies about bio-based materials, which are suitable for structural

  12. Technical research and development of long-spanned bridges; Chodai kyoryo no gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, F.; Yamanaka, M.; Ogawa, K.; Mizukami, Y.; Kano, J.; Watanabe, K. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1996-10-15

    Outlined herein is technical development of long-spanned bridges represented by suspension and cable-stayed bridges. The design of long-spanned bridges requires theoretical analysis of flexibility in which balance after they are deformed by load is taken into consideration. The matrix finite displacement analysis program is developed for optimizing cable-stayed bridge designs and determining suspension bridge shapes as the new major functions. The analysis program, named KASTAN, is also developed for stress analysis of the structure details. A wind tunnel for structure designs is installed to analyze resistance to wind. A number of experiments have been carried out by the tunnel for the designs of segment, main tower and overall bridge models. The means of controlling wind-caused vibration include hydraulic dampers, mass dampers, and combination of high damping rubber and spacer. Cable-stayed bridges are highly flexible, their types being selected by tower height and shape, span ratio and shape of the main beam, and cable position. These bridges constructed by the company include the S-shaped ones whose main beams are supported by cables suspended by two towers of different height, and the others with H-shape towers of high columns which are connected to each other by horizontal beams. 11 refs., 15 figs.

  13. Dynamic assessment of bridge deck performance considering realistic bridge-traffic interaction

    Science.gov (United States)

    2017-09-01

    Concrete bridge decks are directly exposed to daily traffic loads and may experience some surface cracking caused by excessive stress or fatigue accumulation, which requires repair or replacement. Among typical bridges in North America, bridge decks ...

  14. Efficient field testing for load rating railroad bridges

    Science.gov (United States)

    Schulz, Jeffrey L.; Brett C., Commander

    1995-06-01

    As the condition of our infrastructure continues to deteriorate, and the loads carried by our bridges continue to increase, an ever growing number of railroad and highway bridges require load limits. With safety and transportation costs at both ends of the spectrum. the need for accurate load rating is paramount. This paper describes a method that has been developed for efficient load testing and evaluation of short- and medium-span bridges. Through the use of a specially-designed structural testing system and efficient load test procedures, a typical bridge can be instrumented and tested at 64 points in less than one working day and with minimum impact on rail traffic. Various techniques are available to evaluate structural properties and obtain a realistic model. With field data, a simple finite element model is 'calibrated' and its accuracy is verified. Appropriate design and rating loads are applied to the resulting model and stress predictions are made. This technique has been performed on numerous structures to address specific problems and to provide accurate load ratings. The merits and limitations of this approach are discussed in the context of actual examples of both rail and highway bridges that were tested and evaluated.

  15. 33 CFR 118.100 - Retroreflective panels on bridge piers.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Retroreflective panels on bridge... SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.100 Retroreflective panels on bridge piers. The... 12 inches square. (c) To mark bridge piers or channel sides on bridges not required to have bridge...

  16. Improving Bridging from Informatics Practice to Theory.

    Science.gov (United States)

    Lehmann, C U; Gundlapalli, A V

    2015-01-01

    In 1962, Methods of Information in Medicine ( MIM ) began to publish papers on the methodology and scientific fundamentals of organizing, representing, and analyzing data, information, and knowledge in biomedicine and health care. Considered a companion journal, Applied Clinical Informatics ( ACI ) was launched in 2009 with a mission to establish a platform that allows sharing of knowledge between clinical medicine and health IT specialists as well as to bridge gaps between visionary design and successful and pragmatic deployment of clinical information systems. Both journals are official journals of the International Medical Informatics Association. As a follow-up to prior work, we set out to explore congruencies and interdependencies in publications of ACI and MIM. The objectives were to describe the major topics discussed in articles published in ACI in 2014 and to determine if there was evidence that theory in 2014 MIM publications was informed by practice described in ACI publications in any year. We also set out to describe lessons learned in the context of bridging informatics practice and theory and offer opinions on how ACI editorial policies could evolve to foster and improve such bridging. We conducted a retrospective observational study and reviewed all articles published in ACI during the calendar year 2014 (Volume 5) for their main theme, conclusions, and key words. We then reviewed the citations of all MIM papers from 2014 to determine if there were references to ACI articles from any year. Lessons learned in the context of bridging informatics practice and theory and opinions on ACI editorial policies were developed by consensus among the two authors. A total of 70 articles were published in ACI in 2014. Clinical decision support, clinical documentation, usability, Meaningful Use, health information exchange, patient portals, and clinical research informatics emerged as major themes. Only one MIM article from 2014 cited an ACI article. There

  17. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    This publication is unique in its demystification and operationalization of the complex and elusive nature of the design process. The publication portrays the designer’s daily work and the creative process, which the designer is a part of. Apart from displaying the designer’s work methods...... and design parameters, the publication shows examples from renowned Danish design firms. Through these examples the reader gets an insight into the designer’s reality....

  18. The Akashi Kaikyo Bridge and the Storebælt Bridge

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    With the completion of the Akashi Kaikyo Bridge and the Storebælt East Bridge the development of the suspension bridge technology in the 20th century has manifested itself in two impressive structures. With the present echnology may bridges of similar (and also more modest) dimensions...... will undoubtedly be built far into the next century. For bridges going beyond the spans of existing bridges it is, however, likely that new concepts will be developed....

  19. Probability Based Evaluation of Vehicular Bridge Load using Weigh-in-Motion Data

    OpenAIRE

    Widi Nugraha; Indra Djati Sidi

    2016-01-01

    Load and Resistance Factored Design (LRFD) method for designing bridge in Indonesia have been implemented for more than 25 years. LRFD method treating loads and strengths variables as random variables with specific safety factors for different loads and strengths variables type. The nominal loads, load factors, reduction factors, and other criteria for bridge design code can be determined to meet the reliability criteria. Statistical data of weigh-in-motion (WIM) vehicular loads measurement i...

  20. CONSTRUCTION THE BRIDGE PIER AS PARAMETRIC OBJECT USING AUTODESK REVIT

    Directory of Open Access Journals (Sweden)

    K. I. Hladka

    2017-08-01

    Full Text Available Purpose. The work is aimed to solve the following tasks: 1 to investigate the possibilities of Autodesk Revit to create parametric objects; 2 to create an information model of the bridge pier with the possibility of changing the model size without changing geometry of the object; 3 to trace the complexity and feasibility of using parametric models when designing the elements of bridges. Methodology. The studies were carried out using spatial modeling in the Autodesk Revit system. The ratio of the parameters of the object was set, the relationship between individual geometric elements was determined and the changes that were made to the model with the change of the specified parameters were checked. Findings. Support model of two types has been created: for railway bridges and for road bridges. Both types of models change the dimensions and the number of constituent elements in accordance with the entered parameters. The performed work confirms the possibility of creating information parametric models of complex form and the expediency of using them in the design of bridges and not only. Originality. Creation of information models is a modern and relevant topic. But both in the literature and in Internet resources, parametrization is considered on the example of simple objects. The model proposed in the article consists of several dependent geometric bodies; therefore, it opens the topic of objects parameterization more fully and in detail, in comparison with the existing sources. As for the creation of parametric models of the bridge elements - such information is not found in the literature, that is, it is proposed for the first time. Practical value. Parametrization of spatial models allows significantly to accelerate and simplify the process of designing any objects due to the use of typical parametric models in many projects. Especially it concerns the design of bridges, since the standard elements for them, such as support or span are not

  1. Floating liquid bridge charge dynamics

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  2. Simplified method for the transverse bending analysis of twin celled concrete box girder bridges

    Science.gov (United States)

    Chithra, J.; Nagarajan, Praveen; S, Sajith A.

    2018-03-01

    Box girder bridges are one of the best options for bridges with span more than 25 m. For the study of these bridges, three-dimensional finite element analysis is the best suited method. However, performing three-dimensional analysis for routine design is difficult as well as time consuming. Also, software used for the three-dimensional analysis are very expensive. Hence designers resort to simplified analysis for predicting longitudinal and transverse bending moments. Among the many analytical methods used to find the transverse bending moments, SFA is the simplest and widely used in design offices. Results from simplified frame analysis can be used for the preliminary analysis of the concrete box girder bridges.From the review of literatures, it is found that majority of the work done using SFA is restricted to the analysis of single cell box girder bridges. Not much work has been done on the analysis multi-cell concrete box girder bridges. In this present study, a double cell concrete box girder bridge is chosen. The bridge is modelled using three- dimensional finite element software and the results are then compared with the simplified frame analysis. The study mainly focuses on establishing correction factors for transverse bending moment values obtained from SFA.

  3. Engineering and introduction of de novo disulphide bridges in ...

    Indian Academy of Sciences (India)

    The engineeringof de novo disulphide bridges has been explored as a means to increase the thermal stability of enzymes in the rationalmethod of protein engineering. In this study, Disulphide by Design software, homology modelling and moleculardynamics simulations were used to select appropriate amino acid pairs for ...

  4. Alternative and cost-effective bridge approach slabs.

    Science.gov (United States)

    2010-10-01

    The primary objectives of the proposed project are to investigate the causes for any bumps at the end of the bridge approach slab : and to develop remedial measures or alternative designs for a replacement. It is clear that the problem stems from geo...

  5. Planning of resource maintenance at building of railway bridge

    Directory of Open Access Journals (Sweden)

    Klykov Michael

    2017-01-01

    Full Text Available The Publication contains the results of research on the problem of resources provision perfecting of erection processes of railway bridges including consideration of forecasting demand questions to material resources, formations of delivery schedules of materials and designs, definitions of insurance reserves in regards to suppliers of material and technical production.

  6. Bridge esthetic guidelines.

    Science.gov (United States)

    1975-01-01

    As esthetics is not an exact science, differences of opinion occur, even between experts; however, studies had found that in most cases there were statistical preferences. These preferences are presented. For the convenience of the designer, a format...

  7. Super-bridges suspended over carbon nanotube cables

    Science.gov (United States)

    Carpinteri, Alberto; Pugno, Nicola M.

    2008-11-01

    In this paper the new concept of 'super-bridges', i.e. kilometre-long bridges suspended over carbon nanotube cables, is introduced. The analysis shows that the use of realistic (thus defective) carbon nanotube bundles as suspension cables can enlarge the current limit main span by a factor of ~3. Too large compliance and dynamic self-excited resonances could be avoided by additional strands, rendering the super-bridge anchored as a spider's cobweb. As an example, we have computed the limit main spans of the current existing 19 suspended-deck bridges longer than 1 km assuming them to have substituted their cables with carbon nanotube bundles (thus maintaining the same geometry, with the exception of the length) finding spans of up to ~6.3 km. We thus suggest that the design of the Messina bridge in Italy, which would require a main span of ~3.3 km, could benefit from the use of carbon nanotube bundles. We believe that their use represents a feasible and economically convenient solution. The plausibility of these affirmations is confirmed by a statistical analysis of the existing 100 longest suspended bridges, which follow a Zipf's law with an exponent of 1.1615: we have found a Moore-like (i.e. exponential) law, in which the doubling of the capacity (here the main span) per year is substituted by the factor 1.0138. Such a law predicts that the realization of the Messina bridge using conventional materials will only occur around the middle of the present century, whereas it could be expected in the near future if carbon nanotube bundles were used. A simple cost analysis concludes the paper.

  8. Super-bridges suspended over carbon nanotube cables

    International Nuclear Information System (INIS)

    Carpinteri, Alberto; Pugno, Nicola M

    2008-01-01

    In this paper the new concept of 'super-bridges', i.e. kilometre-long bridges suspended over carbon nanotube cables, is introduced. The analysis shows that the use of realistic (thus defective) carbon nanotube bundles as suspension cables can enlarge the current limit main span by a factor of ∼3. Too large compliance and dynamic self-excited resonances could be avoided by additional strands, rendering the super-bridge anchored as a spider's cobweb. As an example, we have computed the limit main spans of the current existing 19 suspended-deck bridges longer than 1 km assuming them to have substituted their cables with carbon nanotube bundles (thus maintaining the same geometry, with the exception of the length) finding spans of up to ∼6.3 km. We thus suggest that the design of the Messina bridge in Italy, which would require a main span of ∼3.3 km, could benefit from the use of carbon nanotube bundles. We believe that their use represents a feasible and economically convenient solution. The plausibility of these affirmations is confirmed by a statistical analysis of the existing 100 longest suspended bridges, which follow a Zipf's law with an exponent of 1.1615: we have found a Moore-like (i.e. exponential) law, in which the doubling of the capacity (here the main span) per year is substituted by the factor 1.0138. Such a law predicts that the realization of the Messina bridge using conventional materials will only occur around the middle of the present century, whereas it could be expected in the near future if carbon nanotube bundles were used. A simple cost analysis concludes the paper.

  9. Simple Evaluation of Load-Carrying Capacity of Multi-Span Folding Bridges based on Floating Supports

    Directory of Open Access Journals (Sweden)

    Jan Marszałek

    2014-12-01

    Full Text Available [b]Abstract[/b]. The papers covers simple evaluation of load-carrying capacity of multi-span folding bridges based on floating supports. Combined bridges built in this approach, could be used as a temporary crossing. The methodology of this evaluation is shown graphically on the basis of designed nomograms for two existing bridge structures i.e. MS-54 and DMS-65, mounted on rigid and floating supports. These nomograms facilitate the simple and fast determination of the impact of changing fixed support into floating support with different bridge length spans on the carrying capacity of the bridge. The paper also presents the influence of long-term use (enlarging the mounting backlash in the joints of these structures on the carrying capacity of the bridge.[b]Keywords[/b]: building, folding bridges, nomograms, assembly clearances

  10. Noise Considerations in Resistance Bridges

    DEFF Research Database (Denmark)

    Diamond, Joseph M.

    1963-01-01

    A signal-to-noise analysis is made of the Wheatstone bridge, where the unknown and standard resistors may be at different temperatures, a situation which occurs in resistance thermometry. The limiting condition is assumed to be dissipation in the unknown resistor. It is shown that the ratio arms...... thermometry, where the noise in the unknown resistor will predominate strongly. An impedance step-up device (transformer or tuned circuit) is valuable in raising the bridge signal and noise level above the noise of the first amplifier tube. However, as the step-up ratio is increased, two counterfactors appear....... With certain assumptions about the noise and grid current of the first tube it is found that the equivalent temperature of a unity ratio (Mueller) bridge used for liquid helium measurements may be 400°K....

  11. A Hybrid Excited Machine with Flux Barriers and Magnetic Bridges

    Directory of Open Access Journals (Sweden)

    Marcin Wardach

    2018-03-01

    Full Text Available In this paper, an U-shape flux barrier rotor concept for a hybrid excited synchronous machine with flux magnetic bridges fixed on the rotor is presented. Using 3D finite element analysis, the influence of axial flux bridges on the field-weakening and -strengthening characteristics, electromagnetic torque, no-load magnetic flux linkage, rotor iron losses and back electromotive force is shown. Three different rotor designs are analyzed. Furthermore, the field control characteristics depending on additional DC control coil currents are shown.

  12. Bridging UX and web development better results through team integration

    CERN Document Server

    Moffett, Jack

    2014-01-01

    The divide between UX and Web development can be stifling. Bridging UX and Web Development prepares you to break down those walls by teaching you how to integrate with your team's developers. You examine the process from their perspective, discovering tools and coding principles that will help you bridge the gap between design and implementation. With these tried and true approaches, you'll be able to capitalize on a more productive work environment. Whether you're a novice UX professional finding your place in the software industry and looking to nail down your technical skills, or a seasone

  13. Study of displacements of a bridge abutment using FEM

    Directory of Open Access Journals (Sweden)

    Wymysłowski Michał

    2016-06-01

    Full Text Available Steel sheet piles are often used to support excavations for bridge foundations. When they are left in place in the permanent works, they have the potential to increase foundation bearing capacity and reduce displacements; but their presence is not usually taken into account in foundation design. In this article, the results of finite element analysis of a typical abutment foundation, with and without cover of sheet piles, are presented to demonstrate these effects. The structure described is located over the Więceminka river in the town of Kołobrzeg, Poland. It is a single-span road bridge with reinforced concrete slab.

  14. Study of displacements of a bridge abutment using FEM

    Science.gov (United States)

    Wymysłowski, Michał; Kurałowicz, Zygmunt

    2016-06-01

    Steel sheet piles are often used to support excavations for bridge foundations. When they are left in place in the permanent works, they have the potential to increase foundation bearing capacity and reduce displacements; but their presence is not usually taken into account in foundation design. In this article, the results of finite element analysis of a typical abutment foundation, with and without cover of sheet piles, are presented to demonstrate these effects. The structure described is located over the Więceminka river in the town of Kołobrzeg, Poland. It is a single-span road bridge with reinforced concrete slab.

  15. Fatigue in Aluminum Highway Bridges under Random Loading

    DEFF Research Database (Denmark)

    Rom, Søren; Agerskov, Henning

    2014-01-01

    Fatigue damage accumulation in aluminum highway bridges under random loading is studied. The fatigue life of welded joints has been determined both experimentally and from a fracture mechanics analysis. In the experimental part of the investigation, fatigue test series on welded plate test...... is normally used in the design against fatigue in aluminum bridges, may give results which are unconservative. The validity of the results obtained from Miner’s rule will depend on the distribution of the load history in tension and compression....

  16. Seismic Retrofitting of an Existing Steel Railway Bridge by Fluid Viscous Dampers

    Science.gov (United States)

    Gangopadhyay, Avijit; Ghosh, Aparna Dey

    2016-09-01

    There are over a lakh of bridges in the Indian Railways, many of which have become seismically deficient, either through aging or due to inadequate seismic design considerations. The extensive damage of bridges all over the world in recent earthquakes has propelled significant advancement in earthquake protection and retrofitting of bridges. Amongst various passive control systems that are reliable as well as cost-effective, Fluid Viscous Dampers (FVDs) are proving to be successful in bridge vibration control. Orificed FVDs, commercially available as Taylor Devices, have already been successfully installed in several bridges worldwide. However, there has been no such application or study related to Indian railway bridges. In this paper, an existing thirty years' old railway bridge in Jharkhand, India, has been analyzed in SAP2000v14 considering reduced stiffness and found deficient when subjected to spectrum-compatible accelerograms. Subsequent retrofitting of the bridge superstructure with FVDs has been carried out and the results indicate substantial reductions in the responses of the bridge deck.

  17. Precast concrete elements for accelerated bridge construction : laboratory testing, field testing, evaluation of a precast concrete bridge, Madison County bridge.

    Science.gov (United States)

    2009-01-01

    The importance of rapid construction technologies has been recognized by the Federal Highway Administration (FHWA) and the Iowa : DOT Office of Bridges and Structures. Recognizing this a two-lane single-span precast box girder bridge was constructed ...

  18. Managing Transitions, Building Bridges: An Evaluation of a Summer Bridge Program for African American Scientists and Engineers

    Science.gov (United States)

    Johnson, Jennifer Michelle

    2016-01-01

    Purpose: This paper aims to highlight the potential of science, technology, engineering and mathematics (STEM) summer bridge programs to promote college persistence by fostering a positive science identity among participants that is culturally consistent with the values and experiences of African American students. Design/methodology/approach:…

  19. Bridging the Vector Calculus Gap

    Science.gov (United States)

    Dray, Tevian; Manogue, Corinne

    2003-05-01

    As with Britain and America, mathematicians and physicists are separated from each other by a common language. In a nutshell, mathematics is about functions, but physics is about things. For the last several years, we have led an NSF-supported effort to "bridge the vector calculus gap" between mathematics and physics. The unifying theme we have discovered is to emphasize geometric reasoning, not (just) algebraic computation. In this talk, we will illustrate the language differences between mathematicians and physicists, and how we are trying reconcile them in the classroom. For further information about the project go to: http://www.physics.orst.edu/bridge

  20. 1,2-bridged quadricyclanes

    International Nuclear Information System (INIS)

    Hart, H.; Cheng-Tai Peng

    1982-01-01

    The readily available benzodihydropentalene 6 and dimethyl acetylenedicarboxylate react to give norbornadiene diester 8, with a three-carbon bridge from C 1 to C 2 . Irradiation of 8 gives the corresponding C 1 -C 2 bridged quadricyclane diester 9, a new ring system. Diester 9 is quite stable, reverting to 8 with a tsub(1/2) of 30 min at 170 0 C. The corresponding diacid 11, also prepared, reverts to its norbornadiene precursor at a considerably lower temperature, possibly as a consequence of acid catalysis. (author)