Seismic response of nuclear power structure on non-bedrock site under oblique incident seismic waves
Since there are fewer and fewer high-quality bedrock sites to choose from,it is inevitable that new nuclear power plants will be built on non-bedrock sites in the future.At this time,soil-structure interaction is a factor that must be considered in the seismic fortification of nuclear power plants.In this paper,a three-dimensional finite element model of the site-pile raft foundation-nuclear power plant is established for Hualong One nuclear power plant planned to be built on a non-bedrock site in China.The direct stiffness method and the boundary substructure method are used to achieve oblique incidence seismic waves input,and the difference in the seismic response of the nuclear power structure when SV waves are incident at three different angles is studied.The effect of soil-structure interaction(SSI)on the structural response is further analyzed.The results show that the non-bedrock site of the nuclear power plant will significantly amplify the bedrock seismic waves,and the peak acceleration amplification coefficient at the bottom of the containment can reach 3.6 when the seismic wave is vertically incident.With the increase of the incidence angle of the seismic wave,the horizontal acceleration response decreases and the vertical acceleration response increases,and the horizontal and vertical acceleration response spectra shift towards the long-period direction and the short period direction,respectively.SSI can significantly affect the seismic response of nuclear power structures in non-bedrock sites.
nuclear power structurenon-bedrock siteincident angleseismic responsedirect stiffness methodsoil-structure interaction(SSI)