The Bracket Strengthening Schemes's Investigation Of Cantilever Suspended Beam Continuous Bridge

The bridge with cantilever suspended beam structural style whose span is less than 100m had been extensive applied in the highway construction with the development of road and bridge building. There are all kinds of diseases in bridges after many years servicing, which is caused by many influencing factors such as lower design load and design flaw of bracket. And the commonly encountered diseases are ones of bracket.The bracket that is key component of cantilever suspended beam bridge is often in complex stress. So the cracks are appeared at the corner of bracket for tension. The regular and prestressed reinforcements are allocated to increase tension nature, but the effect is not so ideal. If this problem isn't solved in time, the bridge structure may be damaged severely. So it is necessary to strengthen the bracket.To combine with firsthand information and disease exploration report of some prestressed concrete continuous bridge (it is used cantilever suspended beam style), the causes about low bearing capacity and wide crakes is analyzed. In this paper, the three reinforcement schemes are suggested against the cause, which is including the sticking steel slab, disposing level prestressing reinforcement, and disposing prestressing reinforcement in direction of principal tensile stress. Meanwhile, when bridge fore and after strengthening is under all kinds of work conditions, such as dead loading, automotive loading, trailer loading, temperature and shrinkage and creep of concrete, principal tensile stress and compressed stress is calculated by the way of finite element analysis software ANSYS. The third strengthening scheme is the most effective one than the others, which can reduce principal stress at bracket, and increase bearing capacity.