Correlation-Based Estimation Method for Cable-Stayed Bridge Girder Deflection Variability under Thermal Action

Thermal actions have a great influence on the girder deflection variability of long-span cable-stayed bridges. The main objective of this study is to investigate the variability of the bridge girder deflection under thermal actions. A monitoring-based analysis of thermal actions and temperature-induced bridge girder deflection for a combined highway and railway cable-stayed bridge has been carried out; the correlation between the girder deflections at different positions is analyzed; a detailed analysis on the correlation between the structural temperature and the girder deflections has also been performed. Furthermore, the double thresholds with a specific probability for the deflection estimates are proposed. It is revealed that a strong linear relationship exists between the structural temperature and girder deflections. The proposed method can provide good estimates of the bridge girder deflections based on long-term monitoring temperature data.