• Journal of Korean Society of Steel Construction
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• v.23 no.6
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• pp.669-677
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• 2011

The multi-span suspension bridge generally has more than three towers and two main spans. To economically and effectively design a multi-span suspension bridge, the proper stiffness ratio of the center tower to the side tower must be determined. This study was conducted to propose a method of figuring out briefly the structural behavior of the towers in a multi-span suspension bridge. In the equivalent suspension bridge model, the main cable of the multi-span suspension bridge is idealized as an equivalent cable spring, and the external loads of horizontal and vertical forces that were calculated using the tensile forces of the main cable were applied on top of the towers. The equilibrium equations of the equivalent multi-span suspension bridge model were derived and the equations were solved via nonlinear analysis. To verify the proposed method, a sample four-span suspension bridge with a main span length of 3,000 m was analyzed using thefinite element method. The displacements and moment reactions of each tower in the proposed method were compared with the FEM analysis results. Consequently, the results of the analysis of the equivalent suspension bridge model tended to be consistent with the results of the FEM analysis.

• Journal for History of Mathematics
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• v.20 no.4
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• pp.93-104
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• 2007

It is well known that a suspension bridge may display certain oscillations under external aerodynamic forces. Under the action of a strong wind, in particular, a narrow and very flexible suspension bridge can undergo dangerous oscillations. The collapse of the Tacoma Narrows suspension bridge caused by a wind blowing at a speed of 42 miles per hour, is one of the most striking examples. In this paper, we study models describing oscillations in suspension bridges and known results.

• Computational Structural Engineering
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• v.6 no.3
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• pp.24-37
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• 1993

본 고에서는 강구조물의 유지관리 중에서도 사장교와 현수교의 유지관리에 관한 기술의 현황과 내구성 향상을 목표로 한 향후의 과제를 중심으로 기술하고자 한다.

• Journal for History of Mathematics
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• v.18 no.2
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• pp.107-116
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• 2005

A suspension bridge is an example of a nonlinear dynamical system, especially systems with the so called jumping nonlinearity. The fact that we deal with a serious and topical problem is demonstrated for example by the collapse of the Tacoma Narrow suspension bridge. So it would be very contributive to determine under what conditions a similar situation cannot occur and find out safe parameters of the bridge construction. In this paper, we show various possibilities how to model the behaviour of suspension bridge. Then we introduce our own results concerning existence and uniqueness of time-periodic solutions.

• Journal of the Earthquake Engineering Society of Korea
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• v.1 no.3
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• pp.45-58
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• 1997

An analysis algorithm and a computer program have been developed to clarify the geometrically nonlinear response characteristics of a suspension bridge subject to the support excitation. The Finite Element procedures are utilized for the application to a self-anchored suspension bridge or to a mono-duo cable suspension bridge. The propagation of earthquake wave is simulated by taking a record as the input at the left anchorage of the bridge, and addign appropriate time delay to the other inputs for the purpose of considering the multi-support effects. According to the application for a mono-duo self-anchored suspension bridge, it has been found that the effects of nonlinear behavior and multi-support excitation are notable for this relatively short-spanned suspension bridge.

• Computational Structural Engineering
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• v.5 no.1
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• pp.28-33
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• 1992

현수교는 상당히 오래전부터 가설되어온 교량형식이기 때문에 구조해석이론도 일찍부터 개발되어 왔다. 그러나 외부 하중에 민감한 구조물이어서, 특히 동적인 하중에 대한 정확한 구조해석방법, 내풍설계방법 등은 아직도 연구가 계속되고 있다. 본 고에서는 현수교의 기본 형상을 소개하고 미력하나마 구조해석방법, 내풍설계방법, 설계시 고려해야 할 기본적인 사항들에 대하여 간략히 정리하여 보았다.

• Journal of Korean Society of Steel Construction
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• v.22 no.6
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• pp.511-521
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• 2010

This paper presents a simplified analysis method of determining the initial shape of suspension bridges, including the horizontal tension force of the main cable and the locations of each hanging point, considering the force equilibrium condition of each hanging point. This method is effective because it requires less effort than the methods used in other studies, for which complicated non-linear analysis was used, to comparatively determine the exact initial shape. The accuracy and validity of the present method are demonstrated by comparing the results of this study with those of previous researchers' numerical examples, including 2D and 3D models.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.72-72
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• 2011

산업의 발달과 건설재료의 개발 및 설계 시공 기술의 급속한 발전으로 더 가볍고 더 긴 경간을 가진 교량이 건설되고 있다. 그러나 교량이 더 길어지고 가벼워질수록 풍하중에 의한 영향은 더욱 크게 받게 되어 여러 종류의 피해를 입게 된다. 이제는 어느 정도 잘 알려진 1940년에 발생한 Tacoma Narrow교의 붕괴사고는 내풍 설계의 필요성을 극단적으로 보여주는 대표적인 예로서 본격적인 내풍 공학 연구에 시발점이 되었다. 현재까지 아직 시공은 되지 않았으나 기본 설계 및 내풍안정성 평가가 완료되 주경간장 3,300m의 Messina교 및 2,800m의 일본해협횡단도로 프로젝트 초장대 현수교(안)의 출현까지 짧은 기간 동안 비약적인 기술 성장을 이루고 있다. 장대교량의 설계시 많은 풍동실험을 거쳐서 내풍안정성이 뛰어난 단면을 찾게 된다. Akashi교의 경우에도 트러스, 싱글박스, 트윈박스 등의 다양한 단면에 대한 풍동실험을 수행한 끝에 최종적으로 트러스 단면을 선택하였다. Great Belt교에서는 싱글박스 단면을 대상으로 다양한 단부 각도에 대한 결과를 바탕으로 최종 단면을 선정하였다. Stonecutter 교에는 트윈박스를 채용하여 기존 싱글박스를 뛰어넘는 도약을 단행하였다. 그리고 Messina교의 경우에는 약 20년에 걸쳐서 설계를 진행해 오면서 점진적으로 단면을 개선하여 최종적으로 트리플박스 단면을 채택하였다. 국내에서도 광양대교의 설계시 싱글박스에서 시작하여 트윈박스의 간격 최적화를 통하여 최종단면을 도출하였다. Akashi교는 최장경간장을 자랑하지만 고전적인 트러스 단면을 사용함으로써 Great Belt교, Stonecutter교, Messina교 등과 같이 혁신적인 단면을 채택한 교량에 비하여 상대적으로 기술적 가치를 인정받지 못하고 있다. 따라서 새로운 내풍 단면의 개발은 교량 설계를 위한 실용적인 측면에서 매우 중요하다. 본 연구에서는 경제적이고 내풍안정성이 우수한 도전적인 현수교 단면을 개발하는데 목적을 두고 있다. 이를 위하여 먼저 교량 계획 단계에 필요한 자료를 제공하기 위하여 기존 강박스 현수교의 제원을 수집하고 그 특성을 분석하여 각종 구조 변수들이 내풍안정성에 미치는 상대적인 영향을 평가하고, 근사적으로 고유진동수를 추정할 수 있는 추정식을 제시하였다. 그 다음으로 초장대 현수교 단면을 개발하기 위하여 다양한 풍동실험을 수행하고 가능한 단면 형상을 제시하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.6 s.40
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• pp.1-11
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• 2004

In the previous study(1), the finite element method was used for the vertical vibration analysis of suspension bridge considering the effects of the shear deformation and the rotary inertia under moving load. This study firstly performs the eigenvalue analysis for the free vertical vibration of suspension bridge using FEM analysis. Next the equations of motion considering interaction between suspension bridge and vehicles/train are derived using mode superposition method. And dynamic analysis was performed using the Newmark $\beta$ Method. Finally through the numerical examples, the dynamic responses of bridges by this study are investigated.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.4
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• pp.114-123
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• 2012

This study is aimed to assess the stability of cable bridge by determining the geometric shape of the suspension bridge among the domestic coastal structures in public use after their completion of construction and the displacement of the target suspension bridge after public use. For this purpose, this study calculated the length between pylon piers for each period, sag, sag ratio and the displacement of pylon. Compared to the management standards for each step across different pylon behaviors of the target suspension bridge, this study found that the target suspension bridge behaves stably within the maintenance standards. To identify the behaviors of a suspension bridge accurately, the priority is put on the determination of geometric shape. Therefore, it is required to determine the surveyed shape model on a regular basis across public use period and increased traffics, which is expected to contribute considerably to ensuring the stability of the suspension bridge in its maintenance.