Application of Dynamic Unstressed State Method in Vertical Rotation Construction of Bridges

A dynamic unstressed length link element and a catenary element are developed based on classical link element and catenary element, and a dynamic unstressed finite element method is proposed which takes unstressed length as input of the finite element and adjusts cable force by modifying unstressed length of element in finite element calculation. Only a finite element model for initial stage of rotation needs to be set in simulating bridge construction of vertical rotation from above to below, and the whole rotation process could be simulated only by adjusting unstressed length of buckle cable and tractive cable, the internal force of buckle, tractive cable and structure in each construction stage can be accurately calculated. This method can also be applied to tension process for cable-stayed bridge, suspension bridges and other cable structure bridges. This paper takes case study to show the correctness of this method and its practical engineering value in application.