• 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.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.1
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• pp.21-29
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• 2016

This paper proposes a method to determine the initial equilibrium state of cable members for preliminary analysis of multi-span suspension bridge under dead load. The proposed method is simpler and more practical than the previous methods used in other studies. The proposed method can be applied to three-span or multi-span suspension bridges. To verify the proposed method, an three-span model as well as four-span models such as New Millenium Bridge in Korea and Yingwuzhou Bridge in China are analyzed. In the verification results, the initial coordinates and tensions of the members calculated by the proposed method are good agreement with those in the previous study for the three-span model and those in the design data of New Millenium Bridge. In addition, the proposed method gives the initial values to keep the initial configuration of Yingwuzhou Bridge.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.49-60
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• 2014

For simple and accurate analysis for behaviors of multi-span suspension bridges which are expected to be frequently constructed as strait-crossing bridges, the deflection theory as the peculiar theory of a suspension bridge can be applied. This paper performs a structural analysis for four-span suspension bridges using the deflection theory. Simply-supported beams with tension are used for girders and the deflections of the beams due to the vertical loads and moments at supports are calculated. The calculation is performed iteratively until the deflections satisfy the compatibility equations of cables. The results of the deflection theory analysis considering tower rigidity are compared with those of the finite element analysis for verification. Importance of the tower rigidity for four-span suspension bridges is confirmed using various compatibility equations of the cable due to variation of the constraint conditions between main cable and top of towers. In addition, the simple parametric analysis for variation of the center tower rigidity is performed.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.239-253
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• 2000

영종대교는 2000년대 수도권 항공수요에 대비하여 영종도와 용유도 일원의 간석지에 건설되어, 인천국제공항과 인천 경서동을 연결하는 총연장 4,420m의 해상교량으로 현수교 3경간(550m), Truss교 18경간 (2,250m), 강상형교 27경간(1.620m)로 구성되어 있다. 영종대교는 10개 차선, 철도 2개 차선의 교량으로 건설된다. 교량이 건설되는 해역은 10,000ton급 선박의 통행이 가능하도록 교하공간 35m의 현수교를 계획 하였으며 경제성을 고려하여 Cable을 보강형에 정착시켰다. 미관을 고려한 경간 분할에 따른 교량의 부상을 방지하기 위하여 단부교각에 Link 구조를 설치하고 접속교를 Counterweight로 이용하였으며 Cable 장력이 저감되도록 Sag비를 1/5(=f/1)로 설정하였다.

• Computational Structural Engineering
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• v.31 no.2
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• pp.22-33
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• 2018

• 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.