Concrete creep and thermal effects on the dynamic behavior of a concrete-filled steel tube arch bridge

A solution to the dynamic problem of concrete-filled steel tube arch bridge including concrete creep and thermal effects are presented. Using a new method to calculate the creep of axially compressed concrete-filled steel tube members, the predicted values of the stress and deformation of the Yajisha Bridge in China are consistent with the site measured data. Using the elastic continuation and plastic flow theory and the unified theory of concrete-filled steel tube columns, the dynamic responses of the Yajisha Bridge are analyzed. The influence of creep effects is more significant, especially in the early aging of concrete. It is found that temperature deteriorates the modulus of elasticity of concrete significantly. Consequently the natural frequencies decrease with temperature increase. Concrete creep and thermal effects are essential to evaluate dynamic behavior of concrete-filled steel tube arch bridge.