【摘要】 为全面认识大矢跨比球面网壳的弹塑性稳定性能,利用ANSYS软件及自编的前后处理程序,有计划地针对132例矢跨比为1/4~1/2的大矢跨比K8型单层球面网壳进行弹性、弹塑性稳定性能分析,并对其中典型算例的塑性发展状况进行了全过程跟踪分析.考察网壳的屈曲模态,分析初始几何缺陷、矢跨比,材料非线性对网壳弹塑性极限承载力的影响.结果表明:大矢跨比情况下,初始几何缺陷的存在会导致网壳的极限承载力降低50%,材料非线性对极限承载力的影响也明显大于常用矢跨比情况,塑性折减系数达到0.4,网壳极易发生提前失稳.建议适当提高大矢跨比球面网壳的稳定性验算安全系数.更多还原

【Abstract】 To further understand elasto-plastic stability behaviors of single-layer reticulated domes with large rise-span ratios,both elasto-plastic and elastic behaviors of 132 domes with rise-span ratios in a range from 1/4 to 1/2 were analyzed.The analysis was concudted by ANSYS and selfcompiled pre-process and post-process programs.Development of plastic deformations of typical cases were studied based on their complete-process curves.The effect of buckling modes,initial geometrical imperfection,rise-span ratios and material nonlinearity on elasto-plastic critical loads of reticulated domes are investigated.Results reveal that the initial imperfection will reduced the critical loads by 50% the effect of material nonlinearity is also amplified,and the plastic reduced coefficients can reach 0.4 by statistical analysis.This kind of structures is sensitive to instability failure,a higher safety coefficient is suggested to promote the reliability level of single-layer reticulated domes with large rise-span ratios.更多还原