考虑地基岩土参数不确定性的核电厂结构随机地震反应分析

在考虑土-结构相互作用(SSI)效应的情况下,引入随机地震反应分析方法,探讨地基岩土参数的不确定性对核电厂地震响应的影响.基于ANSYS程序,采用常数阻抗法,通过设置边界弹簧和阻尼来考虑地基土的作用,并通过设置弹簧和阻尼参数的不确定性,来模拟岩土动态参数的不确定性.针对某1000MW级压水堆核电站反应堆厂房结构,进行随机地震反应的数值仿真分析,并将随机反应结果与确定论分析结果进行了对比.结果表明,随机分析方法是确定论分析方法的有益补充,二者结合能更合理地反映参数的不确定性对结构地震响应的影响.

Stochastic Seismic Response Analysis for Nuclear Power Plant Structure Considering Parameter Uncertainties of Soil

In this paper, a stochastic seismic response analysis for a nuclear power plant structure is carried out considering SSI effect, in order to discuss the influences of the uncertainty of soil on the nuclear power plant structural seismic responses. The soil-structure dynamic interaction is modeled by setting the spring and damping elements on the boundary using the finite element analytical program ANSYS. The uncertainty of the dynamical parameter of soil can be achieved by adjusting the values of these parameters related to the aforementioned elements. Finally, a reactor building in a 1000MW class pressurized water reactor nuclear station is numerically analyzed. The comparison of the numerical results of stochastic method with those of deterministic analyses indicates that this method is practical, and it is a useful balance for the deterministic analytical approach. The combination of these two methods can yield much more reasonable results for evaluating the effects of the property uncertainties of soil on the seismic responses. The conclusions provide some references for the evaluation of the sensitivity of seismic nuclear power plant structural response to uncertain parameters.