为研究带下部钢管柱的单层球面网壳在冲击荷载下的动力响应,在ANSYS/LS-DYNA中建立70m跨度带下部钢管柱的K8型单层球面网壳与正方体冲击物的数值模型并进行数值分析。根据结构动力响应和最终变形,总结了结构在冲击荷载作用下的4种响应模式,并分析了各响应模式下的动力响应(冲击力、节点速度、节点位移、杆件应力)特点。通过改变冲击点位置以及下部柱高度等参数,分析这些参数对带下部钢管柱的单层球面网壳结构响应模式的影响,揭示了结构响应随各参数的分布规律。研究结果表明:水平侧向冲击作用下结构的冲击力主要为等腰三角形脉冲荷载;冲击柱顶点时,上部结构有杆件失效,结构的节点水平位移和杆件应力最大;冲击柱高度较低时,冲击力峰值较小,节点最大水平位移和杆件最大应力较大。
To study dynamic response of the single-layer spherical reticulated shell with sub steel column under impact load,numerical models for single-layer Kiewitt-8reticulated shell with sub steel column at span of 70 m and cubic impactors were established by ANSYS/LS-DYNA program and a series of numerical simulations were carried out.Four response modes for the reticulated shell under impact load were put forward according to dynamic response and plastic deformation.The characteristics of dynamic response of the structure with different response modes,such as impact force,speed of nodes,displacement of nodes,and stress of members were analyzed.The parametric analyses on the dynamic response of single-layer spherical reticulated shell with sub steel column under impact load were carried out.By changing the impact location,column height and other factors,the effects of these parameters on the response mode of singlelayer spherical reticulated shell structures were investigated,and the distribution regularity of the structure response with different parameters was explained.The study results show that the type of impact force is mainly triangular load distribution under impact of the lateral force.When theload is applied on apex,some members of upper structure fail,then horizontal displacement of nodes and stress of members reach its maximum.If the impact height of steel column is lower,the peak value of impact force is smaller,but the maximum horizontal displacement of nodes and the maximum stress of members are still large.