某三代核电站核岛厂房整体筏基设计

Design of the integral raft foundation of a third-generation nuclear power plant

以某三代核电站核岛厂房整体筏基为分析对象,根据整体筏基的结构构造特点,采用软件ANSYS建立了适用的有限元模型,根据规范确定了设计采用的荷载及荷载组合。通过有限元分析,得到整体筏基的内力并据此进行配筋设计,并对整体筏基进行了抗滑移和抗倾覆的稳定性验算。基于该核电站整体筏基构造的复杂性,采用了多种单元类型及连接方式建立复杂有限元模型;采用了瞬态温度场分析方法确定设计基准事故温度下整体筏基受力的最不利状态;采用了时程分析方法计算上部结构作用在整体筏基上的地震作用,降低了传统的拟静力方法的保守性,在保证了整体筏基设计安全的前提下,提高了整体筏基设计的经济性。

The design of the integral raft foundation was studied and described with a third-generation nuclear power plant as analysis object. In the analysis,the finite element model of the whole nuclear island buildings including integral raft foundation was built using ANSYS. The loads and load combinations were selected according to relative design codes.Based on the internal forces obtained from structure analysis,the reinforcement calculation was performed. Moreover,the anti-sliding stability and anti-overturning stability of the raft foundation were evaluated. Based on structural complexity of the raft foundation of the nuclear power plant,various element types and connection types were selected to model the structure considering the complex configuration of the integral raft foundation; the thermal distribution of the raft foundation under accidental case was analyzed utilizing the approach of transient thermal field to determine the most unfavorable internal forces. Time history analysis method was used to compute the seismic lateral force and the maximum lateral force.The application of these technologies reduces the conservatism of traditional quasi-static method and improves the economy of the integral raft foundation design under the premise of safety.