• Title/Summary/Keyword: Composite Steel Box Girder Bridge

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Flexural Design of Double Composite Box Girder over Interior Pier by LRFD Method (LRFD법에 의한 이중합성 박스거더 최대부모멘트 단면 휨 설계)

  • Cho, Eun Young;Shin, Dong Ku
    • Journal of Korean Society of Steel Construction
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    • v.19 no.6
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    • pp.737-749
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    • 2007
  • Flexural design of double composite box girder over the interior pier for three-span continuous bridge was performed by the LRFD method. The maximum span length of the continuous bridge ranged from 80m to 120m and the relative ratio of the span length was assumed to be 1:1.25:1. The girder section was designed for the strength limit state and service limit state with additional design check for constructibility. Before the bottom concrete and compression flange showed a complete composite action, the buckling of lower compression flange was checked. The flexural stiffness and flexural resistance characteristics for the section and for the constituent members such as tension flange, compression flange, and web were analyzed for different thicknesses of the bottom concrete on top of the compression flange. The effect of the distribution ratio of steel between the top and bottom flanges was investigated by analyzing ductility behavior and stress distribution through the girder's depth for several different relative area ratios of steel between the top and bottom flanges. It was found that a total amount of 15% of steel can be saved by applying the double composite system compared with that of the conventional composite system.

Equivalent Shrinkage Strain For Steel-Concrete Composite Girder Bridges (합성거더교의 등가 건조수축 변형률)

  • Bae, DooByong;Jung, Dae Jun
    • Journal of Korean Society of Steel Construction
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    • v.16 no.1 s.68
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    • pp.135-144
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    • 2004
  • Since Modern bridges have a tendency to make the spans continuous and longer, the effect of concrete shrinkage and creep is very important and must be evaluated appropriately for the durability and safety of steel-concrete composite bridges. However, highway design specification in current use prescribes $180^{1\;2}$ as the final shrinkage strain. which is for less value than one resulted from many experimental researches and cause some problems in the construction of composite bridges due to the understimation of shrinkage strain. Thus, in this paper nonlinear analysis with time-steps applying the CEB-FIP(90) provision have been conducted for plate girder bridge, box girder bridge and Preflex beam bridge and the linear equivalent shrinkage strain for the design of composite bridges. which produces the stress equal to the values from the nonlinear analysis, has been calculated by comparing the results with the values following highway design specification. The results yield appropriately double values than $180^{1\;2}$ which highway design specification prescribes.

Analysis of Dynamic Responses for Steel Box Girder and I-girder Bridges under Train Loads (강합성 상자형교 및 소수주형 I형 거더교의 철도차량에 대한 동특성 해석)

  • Choi, Dong-Ho;Na, Ho-Sung;Ahn, Gi-Chul;Kim, Ok-Yeon
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.954-959
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    • 2011
  • The intensity of train load in the railway bridges is relatively large and continues to repeat. Also, the speed of vehicles is very fast. For these reasons, analyses for dynamic response under train load are necessary in the railway bridges. In other words, the dynamic characteristics of steel-composite bridges under train loads should be investigated considering effects of dynamic responses such as vibrations, repeated displacements and acceleration of bridge members. Therefore, in this study, static and dynamic analyses for the steel box girder bridges and I-girder bridges are carried out. Based on analyses results, we investigated and compared dynamic response considering the impact factors of domestic and foreign design specifications.

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Concrete Aging-Dependent Deflection Analysis of Flexural Composite Members Using Sectional Analysis Method (단면해석법을 이용한 합성형 휨 부재의 재령 종속적 처짐해석)

  • Sung Won-Jin;Kim Jeong-Hyeon;Lee Yong-Hak
    • Journal of the Korea Concrete Institute
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    • v.16 no.2 s.80
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    • pp.155-162
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    • 2004
  • An analytical method to predict the time dependent flexural behavior of composite girder is presented based on sectional analysis. The time dependent constitutive relation accounting for the early-age concrete properties including maturing of elastic modulus, creep and shrinkage is derived in an incremental format by the first order Taylor series expansion. The sectional analysis calculates the axial and curvature strains based on the force and moment equilibriums. The deflection curve of the girder approximated by the quadratic polynomial function is calculated by applying to the proper boundary conditions in the consecutive segments. Numerical applications are made for the 3-span double composite steel box girder which is a composite bridge girder filled with concrete at the bottom of the steel box in the negative moment region. The calculated results are compared with those by finite element analysis results. Close agreement is observed between the two approaches.

Design of Dang-San Steel Railway Bridge (당산철교의 설계)

  • 유동호;김선일
    • Computational Structural Engineering
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    • v.12 no.4
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    • pp.69-69
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    • 1999
  • Design of Dangsan Steel Railway Bridge(a part of Seoul Subway Line NO. 2), which is supposed to be replaced after its 15years survice, was done, and the reconstruction has begun in Dec. 1997. The design include new superstruc-ture and bridge piers, retrofitting of the foun-dation, rail system, electric and signal, etc. In this paper, design of the structure is mainly summarized. The main span superstructure, across Han river, is composite section which is com-posed of steel box and reinforced concrete deck slab with 9 span continuous. The superstructure for the approaches is bottom througth type 2-cell steel box girder with steel floor system and concrete deck slab with 3 or 4 span continuous. The bridge piers was planned to be reconstructed based upon the result from the various investi-gations, while the foundation(cassion and pile foundation) was planned to be retrofitted. For superstructure erection, the method of combination of barge bent and heavy lifting and the launching truss method was investigated for the main span and approach spans, respectively.

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Evaluation for the Running Safety and Ride Comfort of Steel Composite Railway Bridge (강합성 철도교량의 주행안전성 및 승차감 평가)

  • Kim, Jung-Hun;Kang, Young-Jong;Kim, Dea-Hyeok;Han, Sang-Yun;Cha, Kyung-Ryul
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.2814-2820
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    • 2011
  • Railway bridge, contact of vehicle needs to design considering the running safety about the running train load of the railway bridge, ride comfort and dynamic safety. Also, upper structure of the railway bridge has to satisfy design standard about moving load(train). So, the railway bridge has to satisfy the requirement for vertical acceleration of the bridge deck, vertical displacement of the bridge and face distortion, which is suggested railway design standard in Korea(2011.5.). In this study, it was investigated and evaluated to the running safety about the running train load of the railway bridge, ride comfort and dynamic safety with railway design standard for steel composite(Steel Box Girder) railway bridge considering KTX, freight train and standard train load.

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Analytical Research on Dynamic Behavior of Steel Composite Lower Railway Bridge (강합성 하로 철도교의 동적거동에 대한 해석적 연구)

  • Jeong, Young-Do;Koh, Hyo-In;Kang, Yun-Suk;Eom, Gi-Ha;Yi, Seong-Tae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.1
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    • pp.27-35
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    • 2019
  • The existing middle-long span railway bridge has been mainly applied to steel box girder bridges. However, the steel box girder bridges have disadvantages in securing the space under the bridge, and the main girder is made of a thin plate box shape, resulting in a ringing noise due to the vibration. Many complaints about noise have been raised. For this reason, there is a need for the development of long railway bridges that can replace steel box girder bridges. In this paper, the characteristics of the steel composite railway bridge currently developed were introduced and a time history analysis was conducted using MIDAS Civil reflecting the speed of KTX load for 40m and 50m bridges. In addition, from the analysis results, the dynamic behavior of target bridges were verified and it was examined whether they meet the dynamic performance criteria proposed in the railway design standards. As a result, all of the bridges under review satisfied the dynamic safety criteria, however, in case of 40m of span, the vertical acceleration value was very large. In order to solve this problem, authors proposed the improvement plan and corrected the cross section to confirm that the vertical acceleration decreased.

Spatial mechanical behaviors of long-span V-shape rigid frame composite arch bridges

  • Gou, Hongye;Pu, Qianhui;Wang, Junming;Chen, Zeyu;Qin, Shiqiang
    • Structural Engineering and Mechanics
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    • v.47 no.1
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    • pp.59-73
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    • 2013
  • The Xiaolan channel super large bridge is unique in style and with greatest span in the world with a total length of 7686.57 m. The main bridge with spans arranged as 100m+220m+100m is a combined structure composed of prestressed concrete V-shape rigid frame and concrete-filled steel tubular flexible arch. First of all, the author compiles APDL command flow program by using the unit birth-death technique and establishes simulation calculation model in the whole construction process. The creep characteristics of concrete are also taken into account. The force ratio of the suspender, arch and beam is discussed. The authors conduct studies on the three-plate webs's rule of shear stress distribution, the box girder's longitudinal bending normal stress on every construction stage, meanwhile the distribution law of longitudinal bending normal stress and transverse bending normal stress of completed bridge's box girder. Results show that, as a new combined bridge, it is featured by: Girder and arch resist forces together; Moment effects of the structure are mainly presented as compressed arch and tensioned girder; The bridge type brings the girder and arch on resisting forces into full play; Great in vertical stiffness and slender in appearance.

Behavior of Composite Steel Bridges According to the Concrete Slab Casting Sequences (바닥판 콘크리트 타설순서에 따른 합성형교량의 거동해석)

  • Kwak, Hyo Gyoung;Seo, Young Jae;Jung, Chan Mook;Park, Young Ha
    • Journal of Korean Society of Steel Construction
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    • v.10 no.2 s.35
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    • pp.233-251
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    • 1998
  • This paper deals with the prediction of behavior of composite girder bridges according to the placing sequences of concrete deck. Based on a degenerate kernel of compliance function in the form of Dirichlet series, the time-dependent behaviors of bridges are simulated, and the layer approach is adopted to determine the equilibrium condition in a section. The variation of bending moments along the bridge length caused by the slab casting sequence is reviewed and correlation studies between section types and placing sequences are conducted with the objective to establish the validity of the continuous placing of concrete deck on the closed steel box-girder which is broadly used in practice.

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Experimental and finite element parametric investigations of the thermal behavior of CBGB

  • Numan, Hesham A.;Taysi, Nildim;Ozakca, Mustafa
    • Steel and Composite Structures
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    • v.20 no.4
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    • pp.813-832
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    • 2016
  • This research deals with the behavior of Composite Box Girder Bridges (CBGBs) subjected to environmental effects such as solar radiation, atmospheric temperature, and wind speed. It is based on temperature and thermal stress results, which were recorded hourly from a full-scale experimental CBGB segment and Finite Element (FE) thermal analysis. The Hemi-cube method was adopted to achieve the accuracy in temperature distributions and variations in a composition system during the daily environmental variations. Analytical findings were compared with the experimental measurements, and a good agreement was found. On the other hand, parametric investigations are carried out to investigate the effect of the cross-section geometry and orientation of the longitudinal axis of CBGB on the thermal response and stress distributions. Based upon individual parametric investigations, some remarks related to the thermal loading parameters were submitted. Additionally, some observations about the CBGB configurations were identified, which must be taken into account in the design process. Finally, this research indicates that the design temperature distribution with a uniform differential between the concrete slab and the steel girder is inappropriate for describing the thermal impacts in design objective.