The Reinforcement Study Of T-Bean Bridge Based On The Seismic Theory

With the growing of traffic volumes and vehicle load, Because of low design load levels and lacking of construction quality control, The existing technology of the old bridges which they have can not meet the current transportation requirements, then Bearing capacity of the old bridge needs to be assessed at the same time take the necessary reinforcement and reconstruction, to increase the load rating of highway bridges. This paper takes WangJiaDu bridge as the engineering background, bases on structural dynamics and theory of bridge seismic design and uses finite element analysis method to analysis the old bridge’s dynamic loading responses which are before and after it has been reinforced,and its seismic responses of three kinds of different reinforcement methods.The paper’s main content is as follows:1. Based on the finite element structure dynamic analysis theory and combined with the time-history method’s key technology to Optimization establish the calculation model and determin the calculation parameters.2. Checking calculation of ultimate bearing capacity of the bridge before the consolidation, and through bridge transverse distribution coefficient, determines most disadvantaged parts of bridge. The calculation results indicate that carrying capacity of bridge before reinforcement only to meet Highway-level-II (original steam20) load rating’s requirements, and bridge safety’s reserve is very small. Due to the low reinforcement ratio of t-beams, so bridge strengthen by bonding steel plate method, and rechecking its bearing capacity after reinforcement.3. Calculate and analyse the bridge structure’s displacement and stress response under moving loads which is before and after reinforcement. Results show that the reinforced bridges’strength and stiffness increase.4. Calculate and analyse Both the highway bridge seismic performance and corresponding reinforcement technique. Input the5.12earthquake waves, using three reinforcement methods, calculate and analyse the bridge structure’s displacement and stress response which are under seismic load, then The Results show that seismic response are large different in the different strengthening methods, T-beam translates into box girder is the best on control of earthquake response.