Monitoring and analysis of thermal effect on tower displacement in cable-stayed bridge

摘要

Thermal actions greatly influence the mechanical behavior of cable-stayed bridges. The objective of this research is to investigate the characteristics of the thermal field and the variability of the quasi-static responses of the bridge towers. Based on the monitoring temperature and displacement data, the distribution of the thermal field for the bridge was studied and the time variability of the tower displacement was investigated. The correlation was analyzed to study the relationship between the temperature and the tower displacements and the towergirder distances. The temperature-induced cable force increments were calculated and a linear regression between the cable force increments and the structural temperatures was performed. A strong linear relationship between the temperature and quasi-static responses of the tower was observed. It is concluded that thermal actions have substantial effects on the quasi-static displacement. Moreover, the temperature-induced cable forces should be fully considered in the safety design of the bridge cables.