Analysis of thermal deformations for a long-span arch bridge using long-term monitoring data

Deformation is an important parameter indicating bridge integrity and serviceability. Fully understanding deformation induced by temperature variations plays an indispensable role in developing deformation-based indexes for bridge performance assessment as well as predicting the displacement amplitude under normal operation environment. In this paper, long-term monitoring data are used to facilitate investigating the thermal deformation properties for a long-span arch bridge. The time-varying features of thermal deformation in longitudinal, vertical, and transversal directions are first discussed. Then, the relationship among thermal deformation in the three directions is extracted. Following that, the thermal correlation of deformation is explored. The results show that the longitudinal and vertical deformation depends heavily on seasons and the thermal deformation in the three directions has close relationships. The vertical displacement has nonlinear correlation with the temperature. The results are expected to provide reference values for similar types of arch bridges.