Study of static and dynamic behavior of T-shape rigid frame bridge reinforced by prestressed external tendon

According to the fact that most defects of this type of bridge are related to loss of prestress,the main method to reinforce old T-frame bridges is to compensate loss of prestress by increasing prestressed tendons. In order to evaluate the effect of this method, the static and dynamic behavior of a T-frame bridge reinforced by prestressed external tendons was analysed by 3D finite element method, and the field test study was also made. The results show that the strength,rigidity,shear resistance and bearing capacity of old bridge have been greatly improved, but partial vibration frequencies of T-frame bridge are close to master frequency of external tendons, so shock absorbing measures should be taken to prevent external tendons from fatigue failure.