[提要]  根据大量算例的计算结果，分析了在竖向阶跃荷载作用下，跨度为40～70m、矢跨比为1/8 ~1/5的单层球面网壳的初始缺陷和初始静位移对其动力稳定性的影响。研究表明，考虑初始静位移与否将对结构的动力失稳临界荷载产生影响，而初始静位移的大小对网壳结构的动力失稳临界荷载影响甚小。另外，初始缺陷对网壳动力失稳临界荷载的影响与其静力稳定有很大差别。
[关键词]  初始缺陷  初始静位移  单层球面网壳  动力稳定性

Based on the comprehensive numerical analysis of single layer reticulated domes subjected to vertical step load, the effects of initial imperfection and initial static displacement on dynamic stability behavior are presented. Finally, some important conclusions are obtained, such as considering initial static　displacement or not have an effect on dynamic stability critical load of reticulated domes whose span is 40m, 50m, 60m, 70m, respectively, with rise-span rati0  1/5, 1/6, l/7,1/8,but the value of initial static displacement has not much effect on that,and the influence of initial imperfection on dynamic stability of reticulated domes is much different from that on static stability of structures.
Keywords:  initial imperfection; initial static displacement; single layer reticulated domes; dynamic stability

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