Equivalent Suspension Bridge Model for Tower Design of Multi-span Suspension Bridges

다경간 현수교 주탑 설계를 위한 등가 현수교 모델

  • 최동호 (한양대학교 건설환경공학과) ;
  • 나호성 (한양대학교 건설환경공학과) ;
  • 이지엽 (한양대학교 건설환경공학과) ;
  • 권순길 (한양대학교 건설환경공학과)
  • Received : 2011.09.07
  • Accepted : 2011.11.30
  • Published : 2011.12.27

Abstract

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.

Acknowledgement

Supported by : 국토해양부

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