核电站泵房不均匀地基的沉降与地基动阻抗计算分析
2016-11-15朱秀云
朱秀云,何 玮,潘 蓉,路 雨
(环境保护部核与辐射安全中心北京 100082)
Abstract:The nuclear power plant(NPP)pump building which is important to supply water for the essential service water system belongs to seismic category I structure.For safety evaluation,the 2D plane strain and 3D FEM model of non-uniform foundation of a pump building are created,and the static settlement calculation at the stages of construction and normal operation is carried out.Furthermore,on the basis of the essential concepts of harmonic response analysis,an improved numerical solution to the soil dynamic impedance of the 3D free field is presented in this paper,by utilizing visco-elastic soil dynamic model,which is especially fit for the numerical simulation of non-homogeneous soil region.The results of the static settlement and the dynamic impedance of the non-uniform foundation are both compared to those of fictitious uniform foundation.The conclusion may provide basis in the aspect of the pump building structure design.
Key word:Pump building of NPP;Non-uniform foundation;Static settlement;Soil dynamic impedance
核电站泵房不均匀地基的沉降与地基动阻抗计算分析
朱秀云,何 玮,潘 蓉,路 雨*
(环境保护部核与辐射安全中心北京 100082)
核电机组的重要厂用水泵房作为核电厂重要的取水构筑物,属于抗震I类物项。为了评价某泵房不均匀地基的安全性,本文分别建立了不均匀地基的平面应变和三维有限元模型,对其进行了施工阶段与正常运行期间的非线性静力沉降计算。此外,本文从谐响应动力求解方法的基本概念出发,基于粘弹性人工边界场地模型,进行了三维自由场地的动阻抗计算,以上结果均与假想的均质地基结果进行对比分析,为下一步泵房结构的抗震计算分析提供了依据。
核电站厂房;不均匀地基;静力沉降;地基动阻抗
核电机组的重要厂用水泵房作为核安全重要物项,属于抗震 I类构筑物[1]。均质地基对核电厂重要构筑物建设的安全性和适应性是有保证的。对于不均匀地基,进行地基的不均匀性对厂房沉降、自由场地的动阻抗特性以及厂房结构地震响应的影响评价是必要的。本文选用在核电厂抗震分析中有广泛应用的粘弹性人工边界场地模型[2-4]分析土 -结构相互作用,该模型是在粘性人工边界[5]的基础上发展起来的,不仅反映了远场介质的辐射阻尼效应,并且体现了远场介质对近场地基区域的弹性支撑作用,可适用于不均匀地基。基于商业软件的二次开发[6-7],可以方便地与有限元法结合,利于工程实现。……
