Abstract: A three-dimension finite element model of a power station at dam toe is built in this paper. The main structures include dam, foundation, powerhouse at dam toe, roof net, and simplified bearing model. Three kinds of bearings, namely, laminated rubber bearing supported with anchor bolt, lead rubber bearing, and hinge support, are compared to find their influence on the upper structure under earthquake action. Result reveals that hinge support is unfavorable for seismic reduction with the shortest natural vibration period and the largest seismic response; also, the maximum displacement of node pairs on the upstream and downstream side of powerhouse are higher than that in the case of lead rubber bearing by 31.74% and 44.5%, respectively. Lead rubber bearing has good ability of releasing support force under earthquake due to good energy absorption effect and better adaptation to shear deformation; moreover, the first principal stress of node pairs on upstream and downstream side of the powerhouse under earthquake is the lowest among the three cases. In conclusion, the lead rubber bearing is recommended.

Key words: laminated rubber bearing supported with anchor bolt, lead rubber bearing, hinge support, power station at dam toe, finite element method, seismic alleviation