基于参数化-超单元法的HFETR乏燃料贮存格架抗震分析

Seismic Analysis of HFETR Spent Fuel Storage Rack Based on Parameterization-superelement Method

为解决HFETR乏燃料贮存格架结构抗震设计中存在的结构迭代设计速度较慢、抗震计算时间较长、多格架分析困难等问题,提出将参数化方法和超单元法组合应用于HFETR格架抗震分析。基于超单元法建立了格架有限元模型;利用APDL和VB对有限元模型的建立和计算进行了参数化处理;对HFETR乏燃料贮存格架进行了多格架抗震计算,并对格架在满载、半载、空载3种装载情况下的应力、滑移和倾倒进行了分析。结果表明:所设计的HFETR格架抗震性能满足要求;参数化-超单元法可用于乏燃料贮存格架的迭代设计和多格架抗震分析。

In order to solve the problems in the design of HFETR spent fuel storage rack, such as slow iterative design speed, long seismic analysis time and difficult multi-rack analysis, a combination of parameterization method and superelement method was proposed to analyze the HFETR spent fuel storage rack. Firstly, a finite element model for seismic analysis of HFETR spent fuel storage rack was established based on superelement method, and the calculation accuracy of the superelement model was verified by modal analysis. Then, APDL program and VB platform were used to parameterize the establishment and calculation of the finite element model of the rack, and the special analysis interface of the rack was established. Through this interface, the size and boundary conditions of the rack can be quickly modified, and the finite element model, analysis type and background calculation can be established quickly, which simplifies the modeling and analysis process of the iterative design of the rack. Finally, the multi-rack seismic analysis of HFETR spent fuel storage rack was carried out by using time-history analysis method. Two seismic working conditions(OBE and SSE) and three loading conditions(full load, half load and no load) were taken into account, altogether six combinations. In this paper, the performance of stress, slip and dumping of HFETR spent fuel storage rack under six combinations was analyzed. The results show that the stress of the rack meets the requirements under the six conditions, and the maximum stress of the base is generated under the condition of half load and SSE. In the six conditions, the slip displacement of the rack is small and no collision will occur. The slip amplitude of the rack is full load, half load and no load from small to large. In other words, the slip amplitude of the rack tends to decrease with the increase of the loading capacity of the spent fuel assembly. The designed rack will not topple under the six conditions. The dumping limit of the rack is the minimum at half load, and the height of the jump is the maximum at half load in the earthquake, so the possibility of the toppling is the maximum at half load in the earthquake, and the half load should be paid more attention to in the analysis of the toppling of the rack. In general, the seismic performance of the designed HFETR rack meets the requirements. The parameterization-superelement method can be applied to the seismic analysis of multiple racks and provide convenience for the iterative design of spent fuel storage racks.