Real-time quantitative evaluation on the cable damage of cable-stayed bridges using the correlation between girder deflection and temperature

Stayed cable is an important prestress-bearing component in cable-stayed bridges, and the cable damage will seriously threaten bridge safety. In this research, the method of real-time quantitative evaluation on cable damage is proposed through monitoring data analysis, correlation analysis, damage evaluation analysis, and validation analysis. Monitoring data analysis shows that temperature has a good linear relationship with girder deflection and cable force. Correlation analysis shows that this relationship is well described by a time-varying multiple linear regression model. In damage evaluation analysis, a new damage index is proposed for real-time quantitative evaluation. Each stay cable has a corresponding damage index, and a large value of damage index indicates a serious damage. The results of experiment and finite element analysis show that the evaluation error of this damage index is very small, which is feasible for real-time quantitative evaluation. This method can provide valuable reference for real-time quantitative evaluation on cable damage of cable-stayed bridges.