The FEM Analysis On Improve The Bearing Capacity Of Arch Bridge By The Energy-released Method

Arch bridge ,which has a long history, is one of the bridges which are built most in China,however,in the wake of improving of road grade, increasing of overweight traffic, weakness of designing and curing, aging of bridge's material and environment impact, many arch bridges has some diseases such as falling of the bearing capacity, increasing deformation and crack in these years.In order to make this bridge ,which have diseases and bearing capacity of not enough, adapt to the national economy and the rapid development of transport,it must be reinforce and improve the carrying capacity."The method of released energy"(ER method) is a kind of new method, new technique and new craftwork to quickly improve carring capacity of bridge. The method changes applied force system of main arch by processing arch springing with special technique , release internal force of main arch springing of original bridge , redistribute internal force of main arch ,improve behavior of original bridge, explore potential of main arch oneself.In this paper, by the finite element numerical analysis, got the boundary element's stiffness matrix and boundary conditions of ER arch bridge,resolved the boundary conditions in finite element method which in reinforcing arch bridge by method. In this paper, take Qingjiang bridge reinforcing project as an example,through the comparison of finite element analysis and the SNGQ's calculation results and the load test results before and after the reinforcemented,it proved that ER method is right and safety and the finite element analysis is feasible. So, reinforcing old and dangerous arch bridge with"the method of releasing energy"to improve bearing capacity is absolutely feasible, and take on important social and economic benefits and practical meaning of engineering.