单层倒悬链型柱面网壳的非线性稳定性研究  

Nonlinear Buckling of Inverted Catenary Single-layer Cylindrical Reticulated Shells

作　　者：贺拥军[1] 刘旦[1] 周绪红[1,2] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]兰州大学,甘肃兰州730000

出　　处：《湖南大学学报（自然科学版）》2012年第6期1-6,共6页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(51178176);湖南大学中央高校基本科研业务费专项基金资助项目

摘　　要：针对拱准线形式为悬链线的单层倒悬链型柱面网壳结构,首先对比分析了其常见的3种网格形式的稳定性能,确定了一种合理的网格布置形式,然后与单层圆柱面网壳的稳定性作了比较,最后进行了大规模的参数分析,较全面系统地研究了单层倒悬链型柱面网壳的静力稳定性,包括长宽比、矢宽比、杆件截面尺寸、初始几何缺陷和荷载不对称分布各参数对结构极限荷载的影响.研究表明:常见网格形式的单层倒悬链型柱面网壳,以斜杆I型的整体稳定性能最好,且相比单层圆柱面网壳,其刚度和极限承载力都得到了较大的提高;长宽比、矢宽比对单层倒悬链型柱面网壳极限承载力影响显著并具有良好的规律性,结构横向加劲肋间距应小于横向宽度;网壳极限承载力与截面等效刚度呈线性关系;初始几何缺陷对结构影响较显著,当缺陷达到波宽的1/300时,网壳极限荷载最大降低达57%;结构对不对称荷载作用不敏感.For the inverted catenary single-layer cylindrical reticulated shells with arch alignment in the form of catenary, the stability of three common grid configurations was analyzed and compared. A reasona- ble grid layout was determined, and the stability with single-layer cylindrical reticulated shells was com- pared. A large scale parameter analysis was carried out, including the effects of length-span ratio, raise- span ratio, member sectional dimension, initial geometric imperfection and unsymmetrical distribution of loads on the ultimate loads of the inverted catenary single-layer cylindrical reticulated shells. The results have shown that the slant rod of type I performs best overall stability capacity in the common grid configu- rations of inverted catenary single-layer cylindrical reticulated shells, and its stiffness and stability bearing capacity are greatly improved, compared with single-layer cylindrical reticulated shells. Raise-span ratio and length-span ratio influence the inverted catenary single-layer cylindrical reticulated shells significantly and have a good regularity, and the spacing of the structure transverse stiffening ribs should be less than the transverse width of the structure. Stability bearing capacity of the reticulated shells and section equiva- lent stiffness are in a linear relationship. The reticulated shells are proved to be sensitive to initial geomet- ric imperfection when the initial imperfection value reaches 1/300 of the width, and the critical loads of the reticulated shells are maximally reduced by 57 %. The reticulated shells are not sensitive to the asymmetric loads.

关 键 词：单层柱面网壳 悬链线拱 稳定性 极限承载力 

分 类 号：TU393.3[建筑科学—结构工程]