Experimental Study On Seismic Reinforcement For Gravity Type Bridge Piers Of Railway

Bridges is a vital part in traffic system of our country. It is important to know the anti-seismic performance of bridge, in which the anti-seismic performance of piers plays a critical role in the anti-seismic performance of the whole bridge, so it is an important work to improve the anti-seismic capability of piers.At present, there are plenty of reinforced concrete piers in bridges of our country, which are designed based on ductility. But railway piers still use a large number of gravity type piers, whose failure mode is brittle failure. So if these piers suffer failure, its consequence will be a disaster.Improving the anti-seismic performance for piers of railway bridges has become an important task for the anti-seismic of bridges. Reinforcing piers is a very important method to improve the anti-seismic performance of bridges, in which the technology for reinforcing piers with concrete is most widely used. This paper will research the anti-seismic performance of model piers, which are reinforced by concrete and whose reinforcement ratio is0.1percent, by pseudo-static test. And carry on a numerical calculation for model piers and to compare it with test result. Main work as follow:(1) Before testing, calculating to get bending moment cracking load yield load ultimate load and ultimate lateral load of model piers so as to prepare for test.(2) Based on literature, summarize the general situation about the anti-seismic of model piers by pseudo-static test at home and abroad.(3) Compare three reinforcement methods including reinforcement with concrete reinforcement with CFRP and reinforcement with steel plate to summarize features and existing disadvantages of each method.(4) Design two model piers, whose ratio is1to8and ratio of reinforcement is0.1percent, then to reinforce them with concrete whose height are0.9meters and1.6meters, and then to study their reinforcement effect including hysteretic behavior and ultimate lateral load etc. by pseudo-static test.(5) Based on numerical calculation of model piers by opensees, to compare their hysteretic behavior and ultimate lateral bearing load with testing results, to testify the availability of the method of reinforcing model piers with concrete in numerical.(6) Based on capacity spectrum method, to carry on the seismic checking computations for a railway pier in the longitudinal direction of bridge in the situation whose seismic fortification intensity is8, site is Ⅲ, seismic peak ground acceleration is0.3g, and design earthquake.