土建结构与主回路耦联模型抗震分析研究

Seismic Resistant Analysis of Coupled Model of Reactor Coolant System and Reactor Building

以巴基斯坦恰希玛核电厂为分析对象,用响应谱分析法以及时程分析法对将土建结构及主回路系统设备按其实际连接(支撑)情况共处一体的耦联计算模型进行抗震分析计算,将其结果与解耦后的主回路系统模型的计算结果相比较,并进行初步的分析探讨。在分析中,用弹性梁单元来模拟主回路系统设备及土建结构,土建结构采用由剪力墙组合的悬臂梁模型。在解耦模型中,各设备的支撑是以具有实际支撑刚度的弹性梁单元支撑在刚性悬臂梁(单点输入)及弹性悬臂梁(多点输入)来模拟。耦联模型的地震载荷按照实际情况,由土建结构的底部输入。通过比较发现,主回路系统设备与土建结构的耦合效应不容忽视,实际抗震设计中不宜用以往的解耦模型进行抗震分析。

Selects Pakistan Chashma NPP as a study object, and seismic resistant analysis is performed with a coupled model using response spectra method and time history method, where reactor building and reactor coolant system are coupled together according to actual connection (or supporting). Finally, analyzed results are compared with those of uncoupled reactor coolant system model. In the analysis, reactor coolant system and reactor building are modeled with elastic beam elements. Reactor building is simulated with cantilever beam model of shear wall combination. In the uncoupled model, supporting of every equipment is modeled using elastic beam element with actual supporting stiffness, which is connected to a rigid cantilever (single-point input) and to an elastic cantilever (multipoint input). According to actual condition, seismic load of the coupled model is inputted from the bottom of reactor building. By comparison, it is shown that the effect of interaction between reactor coolant system and reactor building can not be ignored, and the old uncoupled model for seismic resistant analysis is inappropriate to be applied in actual seismic design.