核反应堆厂房基底隔震设计与地震响应分析

BASE SEISMIC ISOLATION DESIGN AND SEISMIC RESPONSE ANALYSIS OF NUCLEAR REACTOR BUILDINGS

核反应堆厂房是核电站建筑中最重要的组成部分,因此核电站在运行周期内必须确保在所有设想到的事件序列下核反应堆厂房的安全和完整性,特别是在强地震事件中。针对核反应堆厂房进行基础隔震设计与地震响应分析,给出隔震层的详细布置方案,采用ANSYS建立核反应堆厂房的有限元模型并进行非线性时程分析,探讨安全停堆地震和超设计地震作用下隔震与非隔震核反应堆厂房的地震响应。分析结果表明:隔震后核反应堆厂房自振周期大大延长,隔震核反应堆厂房表现为整体平动,基础隔震能使水平加速度大幅降低,结构变形主要集中在隔震层,核反应堆厂房自身变形很小,基底剪力远小于非隔震核反应堆厂房,隔震后有效降低了核反应堆厂房的楼层反应谱,隔震效果明显,显著提高了核反应堆厂房的抗震性能。

Nuclear reactor building is the most significant component of the nuclear power plant.Therefore,the safety and integrity of plant during operating period must be ensured in any design condition and,particularly,in the event of a severe earthquake.Base seismic isolation design and seismic analysis were conducted for nuclear reactor building,including expatiation of layout of the isolation bearings,a three-dimensional finite element model was established and the nonlinear time-history analysis was conducted,and the seismic response of the isolated and nonisolated nuclear reactor building under safe shutdown earthquake and beyond design earthquake were investigated.The results showed that the natural period was prolonged in the isolated nuclear reactor building compared with the nonisolated nuclear reactor building,and the isolated nuclear reactor building showed whole translational motion.The base seismic isolation system had strongly reduced the horizontal accelerations,and the structure displacement was centralized at seismic isolation layer,the lateral drift response of the superstructure was very small.The base shear force of isolated nuclear reactor building was far less than that of non-isolated nuclear reactor building.Base isolation technique could significantly reduce the floor response spectrum of the nuclear reactor building.The isolation effect was so obvious that the isolated nuclear reactor building could greatly improve the seismic behavior clearly.