爆炸载荷特征参数对无限长圆柱壳弹性动态响应的影响

采用含有三角脉冲载荷和准静压载荷的爆炸载荷加载，利用单自由度模型对无限长圆柱壳体（即等效平面应变圆环）的弹性动态响应进行了力学分析，获得了径向位移响应解析解及准静压阶段弹性响应振幅的解析解。基于所得解析解，通过控制变量法分析了载荷压力及载荷分界点时刻（即三角脉冲载荷与准静压载荷作用的分界点时刻）对径向位移最大值、准静压阶段弹性响应振幅的影响规律，更加深入地研究了爆炸载荷对结构响应的影响。本文主要从准静压幅值与三角脉冲峰值的比值以及载荷分界点时刻两个主要特征参数入手，结合结构的呼吸振动频率来研究爆炸载荷对无限长圆柱壳弹性动态响应的影响。在研究中发现存在临界时刻:当载荷分界点时刻早于临界时刻时，径向位移最大值出现在准静压阶段；当载荷分界点时刻晚于临界时刻时，获得了便于直观判断径向位移达到最大值时所处载荷阶段的分区图。基于前述解析解的分析，还获得了不同影响因素导致的振幅变化的单调性分区图，便于判别载荷压力的变化所致的准静压阶段振幅的增减趋势。通过研究获得的爆炸压力载荷对结构响应的影响规律，可为爆炸容器设计以及结构防护基础研究提供参考。

Influence of blast loading parameters on elastic dynamic response of an infinite-length cylindrical shell

The elastic dynamic response of an infinite-length cylindrical shell (equivalent plane strain ring) was analyzed by using the single degree of freedom (SDOF) model under blast loading with triangular pulse load and quasi-static pressure load. The analytical solutions of radial displacement response and amplitude of elastic response under quasi-hydrostatic load were obtained. Based on the analytical solution, the influence of load pressure and the moment of the load boundary point (i.e. the time instant at which the triangular pulse load ends and the quasi-static pressure load begins) on the maximum radial displacement and the amplitude of elastic response in quasi-static pressure stage was analyzed by the control variable method, and the influence of explosion load on the structural response was further studied. The influence of blast loading on the elastic dynamic response of the infinite-length cylindrical shell was studied through the ratio of quasi-static pressure amplitude to triangular pulse peak value and the moment of the load boundary point, combined with the breathing vibration frequency of the structure. It is found that there is a critical time, when the moment of the load boundary point is earlier than the critical moment, the maximum value of radial displacement appears in the quasi-static pressure stage; when the moment of the load boundary point is later than the critical moment, the maximum value of radial displacement can be conveniently determined according to the obtained partition diagram of load stage. Based on the analysis of the above analytical solution, the monotonic zonal diagram of the amplitude variation in quasi-hydrostatic stage caused by the triangular pulse load peak value and quasi-hydrostatic load peak value has obtained, which is convenient to distinguish the increasing and decreasing trend of the amplitude in quasi-hydrostatic stage caused by the load pressure variation. By obtaining the influence of explosion pressure load on the structural response, the current study may provide some guidance for the design of explosion vessels and the basic research of structural protection.