Structural Robustness of Long-Span Cable-Supported Bridges in a Cable-Loss Scenario

Abstract

This study concerns the structural behavior of long-span cable-supported bridges after the sudden rupture of a cable. The load carried by the failed cable must be redistributed to the remaining structure. The cable adjacent to the failed cable receives most of the redistributed load and becomes the critical member. The aim of this study is to find the stress increase ratio of this member. To do this, an analytical approach based on differential equations of the system is used. Then, an approximation function for a simplified bridge model in a cable-loss scenario is derived. The least-squares method is also used to minimize the error of the approximation function. The proposed approximation function has been checked by numerical models, and its accuracy has been proven. The results show that due to increases in the ratio of the bending stiffness of the girder to the axial stiffness of the cables, the stress increase ratio of the critical cable decreases.