单层球面网壳的弹塑性稳定性

为了解和掌握单层球面网壳在静力荷载作用下的弹塑性稳定性能,采用有限元软件ANSYS及自编的前后处理程序对典型单层球面网壳结构稳定性能进行对比分析,初步了解了球面网壳弹性与弹塑性稳定性能的主要差异。在此基础上进行了1000余例K8型单层球面网壳弹性、弹塑性全过程分析,同时考虑竖向均布荷载的不对称分布、初始几何缺陷等因素对球面网壳稳定性能的影响,掌握了以上因素变化对球面网壳弹塑性稳定性能的影响规律,并将其定量化。最后,通过对弹性、弹塑性稳定极限承载力的统计分析,提出适用于K8、K6型球面网壳的塑性折减系数,用以表示材料非线性对极限承载力的影响。这些成果的获得为进一步开展网壳结构的弹塑性稳定性能研究以及工程实践提供了理论依据和技术参考。

Elasto-plastic stability of single-layer reticulated domes

In order to further understand the elastic and elasto-plastic stability behaviors of single-layer reticulated domes under static loads,typical cases of single-layer reticulated domes are analyzed and compared by using the finite element software,ANSYS.Based on the results,more than 1000 elastic and elasto-plastic complete-process analyses for the Kiewitt single-layer reticulated domes have been carried out to study the influence of various factors,such as initial geometry imperfection and unsymmetrical action of loads,and quantitative results were obtained.Through a statistical analysis of elastic and elasto-plastic stability critical loads,a plasticity reduction coefficient for the Kiewitt single-layer reticulated domes is proposed to reveal the influence of material nonlinearity on critical loads.