• Smart Structures and Systems
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• 제33권1호
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• pp.1-16
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• 2024

The investigation on vehicle-bridge coupling system (VBCS) is crucial in bridge design, bridge condition evaluation, and vehicle overload control. A real-time hybrid testing (RTHT) method for VBCS (RTHT-VBCS) is proposed in this paper for accurately and economically disclosing the dynamic performance of VBCSs. In the proposed method, one of the carriages is chosen as the experimental substructure loaded by servo-hydraulic actuator loading system in the laboratory, and the remaining carriages as well as the bridge structure are chosen as the numerical substructure numerically simulated in one computer. The numerical substructure and the experimental substructure are synchronized at their coupling points in terms of force equilibrium and deformation compatibility. Compared to the traditional iteration experimental method and the numerical simulation method, the proposed RTHT-VBCS method could not only obtain the dynamic response of VBCS, but also economically analyze various working conditions. Firstly, the theory of RTHT-VBCS is proposed. Secondly, numerical models of VBCS for RTHT method are presented. Finally, the feasibility and accuracy of the RTHT-VBCS are preliminarily validated by real-time hybrid simulations (RTHSs). It is shown that, the proposed RTHT-VBCS is feasible and shows great advantages over the traditional methods, and the proposed models can effectively represent the VBCS for RTHT method in terms of the force equilibrium and deformation compatibility at the coupling point. It is shown that the results of the single-degree-of-freedom model and the train vehicle model are match well with the referenced results. The RTHS results preliminarily prove the effectiveness and accuracy of the proposed RTHT-VBCS.

• 한국전산구조공학회논문집
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• 제24권3호
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• pp.283-288
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• 2011

내진설계에서 설계자가 제시해야 하는 사항은 구조물의 항복과정이 원칙적으로 연성파괴메카니즘으로 구성되는 것이다. 일반교량의 연성파괴메카니즘은 연결부분과 교각기둥 두 구조부재 중 교각기둥이 먼저 항복하도록 설계되어야 한다. 그러나 불필요하게 강성이 큰 하부구조가 사용되는 국내의 설계관행에 의해 지진하중은 크게 발생하게 되므로 연성파괴메카니즘을 확보하기가 어렵다. 이러한 문제는 내진설계가 기본설계 단계에서 수행되지 않아 발생한다. 이 연구에서는 일반교량을 해석대상 교량으로 선정하고 기본설계 단계에서 연결부분과 하부구조의 설계강도를 결정하는 내진설계를 수행하여, 이러한 설계방식으로 타설계에서 결정되는 구조부재를 변경하지 않아도 연성파괴메카니즘을 확보할 수 있다는 것을 제시하였다.

• Smart Structures and Systems
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• 제14권4호
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• pp.501-516
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• 2014

The rocking pier system (RPS) allows the columns to rock on beam or foundation surfaces during the attacks of a strong earthquake. Literatures have proved that seismic energy dissipated by the RPS through the column impact is limited. To enhance the energy dissipation capacity of a RPS bridge substructure, frictional hinge dampers (FHDs) were installed and evaluated by shaking table tests. The supplemental FHDs consist of two brass plates sandwiched by three steel plates. The strategy of self-centering design is to isolate the seismic energy by RPS at the columns and then dissipate the energy by FHDs at the bridge deck. Component tests of FHD were first conducted to verify the friction coefficient and dynamic characteristic of the FHDs. In total, 32 shaking table tests were conducted to investigate parameters such as wave forms of the earthquake (El Centro 1940 and Kobe 1995) and normal forces applied on the friction dampers. An analytical model was also proposed to compare with the tested damping of the bridge sub-structure with or without FHDs.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.589-594
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• 2003

The paper proposes a methodology of identifying a substructure model of an existing structure when correct sectional and material properties of the structure are not known. A substructure model is identified by estimating boundary spring constants and stiffness properties of the substructure. Both of static and modal system identification methods have been applied using responses measured at limited locations within the substructure. In defining a substructure model it is required that computed structural responses be consistent with the actual behavior of the part of the structure. Simulation studies on a continuous beam structure and an application to an actual bridge have been carried with static and modal responses. The results and associated problems are discussed in the paper

• Structural Engineering and Mechanics
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• 제47권2호
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• pp.265-286
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• 2013

A study on economic performances of consecutive multi-span suspension bridges is carried out. In this part of the study, material amount and structural cost estimation formulas of the bridges is derived based on the structural ultimate carrying capacity. The bridge cost includes the part of superstructure and the part of substructure. Three types of bridge foundations, bored piles, concrete caissons and floating foundations, are considered in substructure. These formulas are to be used for the parametric study of the bridge cost in order to define its more economical layout under different conditions in the part two of the study.

• 한국해양공학회지
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• 제20권5호
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• pp.63-69
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• 2006

An isolated bridge using a laminated rubber bearing provides an elastic support of continuous span and prevents the transmission of excessive seismic force from the substructure of the bridge, which uses a metal bearing, as this permits a relative displacement between the super-and substructure. Hawever, this kind of bridge is caused long periodic, as a result of enlargingtotal thickness of the rubber, since it corresponds to temperature change and increases the horizontal displacement of the superstructure. This paper uses a numerical study to describe the pounding problem between adjacent decks when subjected to a strong earthquake. Furthermore, numerical results are clarified for the buffer rubber used to mitigate the pounding force between adjacent decks.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.295-301
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• 2001

For the seismic analysis of typical roadway bridges provisions are given in most codes for analysis models, which describes however only fundamental modelling methods according to the basic theories of structural dynamics. In practice even conventional non-seismic analysis models, separate super- and substructure models, are applied, which are not adequate because of neglecting connection elements. In this study three typical roadway bridges, a Steel box bridge, a PC beam bridge and a PC box bridge are selected and simple models integrating super- and substructure as well as connection elements are given. The simple models are composed with frame elements with lumped masses representing stiffness and mass characteristics of the selected bridges. To check the properness of the simple models, analysis results with the simple models are compared with those obtained with detailed models in view of bridge failure mechanisms. It is proved that the simple models can be used in the preliminary design phase fur the determination of failure mechanisms of typical roadway bridges.

• 대한토목학회논문집
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• 제26권1A호
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• pp.173-181
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• 2006

지진격리교량은 내진설계가 도입된 이후 실무에서 많이 설계, 시공되고 있으나 현재 실무에서 제시하고 있는 설계결과는 불필요하게 높은 기능수행수준과 취성파괴메커니즘으로 내진설계개념에 부합하는 설계라 할 수 없다. 이는 기존의 설계관행인 하부구조의 과다한 강성과 내진설계방식의 인식부족에 기인한 것이다. 이 연구에서는 기존의 설계관행에 의해 설계된 지진격리교량을 선정하고, 동일한 교량에 격리받침 대신 강재받침을 사용한 강재받침교량을 설정하여 비교내진설계를 수행하였으며, 이로부터 내진설계에서 요구되는 성능수준을 확보하기 위한 각 교량의 내진설계절차를 제시하였다. 강재받침교량에 비해 지진격리교량은 시산법과 반복해석을 적용해야 하는 복잡한 설계절차가 요구되는 반면 상대적으로 높은 기능수행수준을 제공한다는 것을 확인하였다. 그러나 강재받침교량도 하부구조 강성을 조정하면 요구되는 기능수행수준을 만족할 수 있으므로, 연성파괴메커니즘의 확보가 불가능한 경우 지진격리교량을 대안설계로 고려하는 것이 합리적인 내진설계과정이라는 것을 제시하였다.

• 한국지반환경공학회 논문집
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• 제14권12호
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• pp.13-22
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• 2013

교량의 하부구조는 고정하중과 차량 활하중 등의 수직 방향 하중을 지지할 뿐만 아니라 횡방향 하중을 지지해야 하므로 교량의 안전성에 있어 매우 중요한 구조 요소임과 동시에 경제성에 영향을 미치는 요소이다. 따라서, 본 연구에서는 말뚝캡 직상부에 모멘트 집중을 피할 수 있는 말뚝형 기둥의 현장 적용성에 대한 기초적인 사례연구를 수행하였으며, 말뚝 본체의 구조성능보다는 지반의 지지력이 더 큰 영향을 미치는 것으로 분석되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.660-663
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• 2001

There is a mechanical device between the superstructure and substructure of a bridge, which transmit vertical load of superstructure to the substructure and absorb horizontal displacement of super structure due to thermal, dynamic, load, etc. In order to meet two requirements at once, the structure of roller between plates is widely used, and this roller between plates is widely used, and this roller shoe system is known to have smaller horizontal movement resistance than any other type of bridge shoe. In this study, rolling friction resistance characteristics of roller-plate friction system is investigated according to roller dimension, vertical load, hardness and roughness of roller and plate. On the base of the results, the rolling friction resistance of large scale roller shoe is evaluated using model experiment.