Determination of reasonable internal force state for cable-stayed bridge without backstays

After years of operation, cable-stayed bridge without backstays may present an unreasonable internal force state, which is a potential hazard. The cable-stayed bridge without backstays applied in the Jinzhou Bridge is selected as an engineering background to analyze its reasonable internal force state and corresponding cable force. First, the measured results of the geometric alignment and cable force are compared with the design limits, and the results uncover that the current cable force fails to satisfy the actual requirements. Secondly, finite element (FE) models of the bridge are established and modified based on the measured cable forces, so that they can be applied to analyze the internal force states of the beam and tower. It is found that the stress state exceeds the design limit. Then, the stress sensitivity of the beam and tower is analyzed by altering the cable forces, and the feasible region of structural stress under dead load is obtained after analysis. Finally, both the structural reasonable internal force state and the corresponding cable forces are determined based on the results of sensitivity and feasible region analysis.

Automated summary

Based on the analysis of the engineering background of the cable-stayed bridge without backstays in Jinzhou Bridge, it is found that the current cable force fails to satisfy the actual requirements. Finite element models are established and modified to analyze the internal force states of the beam and tower, and determine the reasonable internal force state and corresponding cable forces.