考虑SSI效应的核电厂直立翼墙与排水沉管交叉体系静动力响应分析

某核电厂的联合泵房两侧直立翼墙以及排水沉管为交叉设计，且属抗震I类物项，因此，考虑土-交叉体系结构动力相互作用是抗震安全性评价的关键技术问题。以实际核电厂条件为背景，基于ANSYS分析平台建立了翼墙-沉管交叉体系-地基静动力分析模型，运用UPFs创建的粘弹性边界单元考虑无限地基辐射阻尼影响及地震动的输入，并精细化模拟地基材料的力学特性及交叉体系的空间分布形态，开展了静动力荷载联合作用下翼墙-沉管交叉体系的响应分析，探究交叉体系结构的应力、变形及加速度峰值等响应的变化规律。计算结果表明：直立翼墙与排水沉管交叉部位出现了应力集中现象，翼墙结构的竖向加速度响应与竖向及顺沉管水平向位移变形有较大变化，沉管在交叉部位的响应也有显著增加。研究成果可为核电厂取水工程构筑物的类似交叉体系设计提供技术参考。

Static-dynamic Response Analysis of Upright Wing Wall and Drainage Immersed Tube Cross System of NPP Considering SSI Effect

The upright wing walls on both sides of the joint pump house and the drainage immersed tube of a nuclear power plant are crossed design and belong to the seismic class I items, therefore, considering that the soil-crossing system structural dynamic interaction is a key technical issue for seismic safety evaluation. Based on the actual nuclear power plant site conditions, the ANSYS analysis platform is used to establis h a hydrostatic analysis model of the wing wall-immersed tube crossover system-foundation, through the viscoelastic boundary units created by running UPFs to consider the influence of infinite foundation radiation damping and the input of ground vibration, and refine the simulation of the mechanical properties of the foundation materials and the spatial distribution pattern of the crossover system. The response analysis of the crossed wing wall-immersed tube system was carried out to investigate the changes of stress, deformation and acceleration peak of the crossed system. The calculation results show that the stress concentration phenomenon occurs at the intersection of the upright wing wall and the drainage immersed tube, and the vertical acceleration response of the wing wall structure had a great change from the vertical and horizontal displacement deformation of the drainage immersed tube, and the response of the immersed tube in the intersection had also increased significantly. The research results can provide technical reference for the design of similar crossover systems for nuclear power plant water intake engineering structures.