Elasto-plastic stability of single-layer reticulated domes with initial curvature of members
Elasto-plastic stability of single-layer reticulated domes with initial curvature of members
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DOI：
10.1016/j.tws.2012.01.012
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发表时间：
2012-11
影响因子：
6.4
通讯作者：
F. Fan;Jiachuan Yan;Z. Cao
中科院分区：
文献类型：
--
作者：
F. Fan;Jiachuan Yan;Z. Cao
杆件初曲率是球面网壳结构不可避免的几何缺陷。为研究考虑杆件初曲率时单层球面网壳的稳定性，提出了多梁法模拟杆件初曲率，并利用ANSYS软件采用两种建模方法引入杆件初曲率。首先，根据构件初曲率的随机性，引入了随机缺陷模态法。以Kiewitt-8型球面网壳为例，分析了角度和振幅随机变量对球面网壳稳定性的影响。其次，提出了修正的一致缺陷模态法，该方法是求解具有构件初曲率结构最低屈曲荷载的有效方法。基于该方法，以Kiewitt-6和Kiewitt-8型单层球面网壳为例，分析了杆件初曲率对结构稳定性的影响，定量地得到了杆件初曲率对理想结构和节点偏差结构稳定性的影响。结果表明，对于理想结构和节点偏离结构，杆件初曲率的存在可以明显降低结构的屈曲荷载。构件的初曲率可以改变结构的屈曲模式和塑性发展。杆件初曲率对单层球面网壳弹塑性稳定性的影响不容忽视。
Initial curvature of members is an inevitable geometrical imperfection for reticulated domes. To investigate the stability of single-layer domes with initial curvature of members, the multi-beam method was presented to simulate the initial curvature of members, and two modeling methods were adopted to introduce the initial curvature of members for reticulated domes by means of ANSYS. First, the random imperfection mode method was introduced according to the randomness of initial curvature of members. The example of a Kiewitt-8 dome was used to explain the method and investigate the influence of angle and amplitude random variables on the stability of reticulated domes. Second, the modified consistent imperfection mode method was obtained, which was an efficient method to evaluate the lowest buckling load of the structure with initial curvature of members. Based on this method, the Kiewitt-6 and Kiewitt-8 single-layer reticulated domes were taken as examples to analyze the stability of structures with initial curvature of members, and the influences of initial curvature of members on the ideal structure and the structure with nodes deviation were obtained quantitatively. The results show that, for the ideal structure and the structure with nodes deviation, initial curvature of members can decrease the buckling load of the structure obviously. Initial curvature of members can change the buckling mode and plasticity development of the structure. The influence of initial curvature of members on the elasto-plastic stability of single-layer reticulated domes cannot be neglected.