Numerical Study on Cable Force Adjustment System for Replacing Slings of In-Service Suspension Bridges

Abstract To conduct a systematic investigation on the replacement scheme for slings in service of suspension bridges, five feasible tensioning schemes were determined based on numerical simulation and analytical methods using the sling replacement project of an existing bridge as a case study. The safety performance of the bridge was evaluated by considering parameters such as sling position, quantity, order, and force value. According to the coupling relationship between different slings during the tensioning process, a precise analytical calculation model for adjusting cable force of the suspender is determined. The findings demonstrate that the dynamic performance of the completed bridge solely depends on its final state and remains unaffected by the intermediate tensioning process of suspension. The research findings suggest that symmetrically batch or stepwise tensioning can be applied to the suspension bridge slings with cable adjustment sequence from both ends to middle span replacement scheme to minimize structural response and optimize mechanical properties.