Investigation of Temperature Effects on Steel-Truss Bridge Based on Long-Term Monitoring Data: Case Study

Abstract

The time-varying average and differential temperatures may significantly change the performance of steel truss bridges, which may increase the difficulties for bridge design, construction, and maintenance. Because hundreds of steel members usually have different geometric dimensions, the temperature effect on the steel truss bridge is extremely complicated, and no general formula is available for predicting temperature-induced responses. In this study, the 2-year field monitoring data collected from a 108-m-long steel truss bridge are utilized to investigate the temperature effects on strain responses. In particular, the relationships between temperature-induced stress and standard temperature actions are investigated using correlation analysis and numerical simulation. Accordingly, the simple general formula is provided to capture the relationships between temperature distributions and temperature-induced strains. The accuracy of the proposed formula is verified using the field monitoring data of the box-shaped members and the H-shaped members. The notable vertical temperature gradients are usually observed in box-shaped members, which can generate larger thermal strain responses than H-shaped members. The results of this study could provide a simple and relatively general solution to predict the temperature-induced strain of steel truss bridges. Meanwhile, this conclusion drawn may provide references for the design and maintenance of steel truss bridges.