Determination of Replacement Cable Force of in-Service Suspension Bridge Based on Refined Modelling Approach

Abstract

In this paper, the replacement cable force of suspension bridge slings in service is systematically analyzed by adopting the coupling analysis model of internal force influence matrix and displacement influence matrix. The sling replacement project of an existing bridge serves as the basis for considering the technical condition and stress state of slings and other components comprehensively. Key control indexes, such as internal force, offset, linear or adjacent cable force change, are defined according to vehicle traffic requirements and structural safety considerations. Refined finite element numerical calculation is employed to determine the target cable force applied to the replacement sling, while analyzing changes in key control indexes of relevant components and structures during adjustment. The target cable force of the replacement sling is adjusted and determined based on a comparison with the target demand index. Compared with the traditional influence matrix method, the double matrix method also has the advantage that it does not need to select the initial adjustment cable force, which avoids the problem that the convergence result may not be obtained, and aims to provide a basis for the subsequent calculation of cable force replacement when the suspension bridge is in service.