1. Hubei Key Laboratory of Roadway Bridge & Structure Engineer; Wuhan University of Technology; Wuhan 430070, China；
2. School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, China
ANALYSIS OF THE INFLUENCE OF FOUNDATION UPLIFT ON STRUCTURE SEISMIC RESPONSE
The structure foundation will separated from the supporting soil if the earthquake is big enough, which is the so called the phenomenal of foundation uplift. This phenomenal, unfortunately, is always neglected in seismic response analysis of soil-structure interaction (SSI) system. The designed seismic level for nuclear power plant (NPP) is usually very big because of its specificity, therefore, the foundation of nuclear power plant will probably separate from the supporting soil. Based on a simplified NPP calculation model and the by employing the contact function and spring element in the software ANSYS, four cases are considered, which are: (1) foundation fixed; (2) the foundation uplift is considered and the SSI effect is not considered; (3) the SSI effect is considered and foundation uplift is not considered; (4) both the foundation uplift and the SSI effect are considered. The influences of the SSI effect and foundation uplift on structure seismic response are analyzed by comparing the computation results. It is showed from the computation results that: (1) the influence of the SSI effect on structure seismic response can not be neglected; (2) foundation uplift influenced structure vertical response mainly, and has a very little influence on structure horizontal response. The research results in the paper can provide some references for seismic design of NPP.
1. Hubei Key Laboratory of Roadway Bridge & Structure Engineer; Wuhan University of Technology; Wuhan 430070, China；
2. School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, China
Abstract：The structure foundation will separated from the supporting soil if the earthquake is big enough, which is the so called the phenomenal of foundation uplift. This phenomenal, unfortunately, is always neglected in seismic response analysis of soil-structure interaction (SSI) system. The designed seismic level for nuclear power plant (NPP) is usually very big because of its specificity, therefore, the foundation of nuclear power plant will probably separate from the supporting soil. Based on a simplified NPP calculation model and the by employing the contact function and spring element in the software ANSYS, four cases are considered, which are: (1) foundation fixed; (2) the foundation uplift is considered and the SSI effect is not considered; (3) the SSI effect is considered and foundation uplift is not considered; (4) both the foundation uplift and the SSI effect are considered. The influences of the SSI effect and foundation uplift on structure seismic response are analyzed by comparing the computation results. It is showed from the computation results that: (1) the influence of the SSI effect on structure seismic response can not be neglected; (2) foundation uplift influenced structure vertical response mainly, and has a very little influence on structure horizontal response. The research results in the paper can provide some references for seismic design of NPP.
王国波1，王亚西1，于艳丽2，何卫2. 基础提离对核电站结构地震响应的影响分析[J]. 振动与冲击, 2015, 34(7): 228-233.
WANG Guobo1，WANG Yaxi1，YU Yanli2，HE Wei2. ANALYSIS OF THE INFLUENCE OF FOUNDATION UPLIFT ON STRUCTURE SEISMIC RESPONSE. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(7): 228-233.
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