爆炸冲击荷载下土中平封头圆柱壳动力屈曲研究

Dynamic Buckling of Underground Flat-Closure Cylindrical Shells under Explosion Loads

爆炸冲击荷载下土埋储油设施的动力响应研究是涉及公共结构设施安全的重要课题。以平封头圆柱壳结构模拟储油罐,根据土中圆柱壳的受力特征,利用修正的Winkler模型对圆柱壳-土相互作用进行描述,并给出确定模型参数的方法。基于在爆炸压力模拟器内进行的土埋钢质圆柱壳模型的爆炸压力加载实验,确定了壳壁周边荷载分布的合理简化模型。进而对平封头圆柱壳结构的动力屈曲问题进行了有限元数值计算,并根据Budiansky-Roth准则确定了临界屈曲荷载。通过对多工况下数值计算结果的分析,给出了临界屈曲荷载与土体弹性常数K的关系。

Investigation of dynamic response of the underground oil storage facility subjected to explosion loads is an important problem. The oil tank can be predigested as a flat-closure cylindrical shell structure. Considering the stress characteres of underground cylindrical shells, the amendatory Winkler model was used to simulate the interaction between cylindrical shell and soil,and a method to determine the related parameters was presented. With the explosion simulation device, a model experiment of underground steel cylindrical shell under explosion loads was completed. An appropriately simplified model of the peripheral explosion loads distribution of the cylindrical shell was assigned according to experimental results. Finete element analysis for the dynamic buckling of flat-closure cylindrical shell was carried out and the critical buckling loads were determined by Budiansky-Roth criterion. Relastionship between critical buckling loads and soil elastic constant K was determined according to the multi-state computation results.