Research On New Reinforcement Method Of Rigid-frame Arch Bridge In-service

Since the seventies of last century, a large number of rigid-frame arch bridge have been built in China. In recent years, with the rapid growth of traffic road scales and heavy load vehicles also largely increase along with it, moreover, rigid-frame arch bridge have its own shortcomings of stiffness, so that diseases are common exist in them. And the comfort and safety of pedestrians have been seriously affected. Therefore, it is very important to find effective ways to reinforce this type of bridge.This paper starts the research from the engineering of a rigid-frame arch bridge visual examination. Firstly, the typical diseases and the intrinsic defects of the rigid-frame arch bridge are analyzed in detail. Secondly, in order to complete the carrying capacity analysis and find the weak point of the rigid-frame arch bridge, this paper use ANSYS to build and modify the finite element model with the static and dynamic load test data so that it is more consistent with the actual working situation. Thirdly,on the basis of common reinforcement methods, a new method that in the perspective of enhancing the integrity of the bridge is put forward creatively. The new method increasing a rectangular plate between the arch rib near the arch foot, removing the old prefabricated deck and cast new decks, so that the discrete arch ribs are changed into integral ones. It is proved by the finite element analysis that this new method have more advantages than the common ones in the respects of improving the integrity and working performance of the bridge. Finally, this method is applied to an engineering of reinforcement. The validity of the new method is proved by the comparison of the load test before and after the reinforcement. The calculation and analysis show that the new method can effectively enhance the integrity and carrying capacity of the rigid-frame arch bridge. The Engineering practice also indicates that the bridge reinforced by this new method have Significant improvement in stiffness and strength, so the method mentioned has a certain reference value for similar engineering.