基于初弯曲单元的某弦支穹顶非线性稳定承载力分析  

Nonlinear stability bearing capacity analysis for a suspended dome based on the initial curvature elements

作　　者：周臻[1,2] 吴京[1,2] 孟少平[1,2] 

机构地区：[1]东南大学混凝土及预应力混凝土结构教育部重点实验室,南京210096 [2]东南大学城市工程科学国际研究中心,南京210096

出　　处：《计算力学学报》2010年第4期721-726,共6页Chinese Journal of Computational Mechanics

摘　　要：在单元的随动坐标系下,建立了初始弯曲对杆单元轴向刚度影响的计算公式,导出了考虑初始弯曲的非线性杆单元刚度矩阵;从经典的梁-柱理论出发,给出了考虑初始弯曲的非线性空间梁单元切线刚度矩阵推导过程。将建立的初始弯曲单元应用于弦支穹顶结构算例的非线性稳定承载力分析,研究了杆件初始弯曲对结构整体非线性稳定性能的影响,结果表明,杆件初始弯曲的存在会降低结构的整体刚度和极限承载力,而在不同的初始预应力状态下,极限荷载随初始弯曲增加都基本呈线性下降,并且其关系曲线基本平行。本文建立的基于初弯曲单元的非线性分析方法,可推广应用于各种类型空间网格结构的非线性分析,为结构设计方案的选择提供更为科学的依据。In the element follow-up coordinate system,the computation formulation considering the influence of initial curvature on the link element is established,and the element stiffness matrix including the effect of initial curvature is derived.Then the tangent stiffness matrix of initial curvature beam element is deduced base on classical beam-column theory.Finally,the nonlinear stability bearing capacity analysis is carried out for the suspended dome structure by using the initial curvature link and beam element,and the influence of the member initial curvature on the structural nonlinear stability performance is investigated.The results show that the structural stiffness and limited bearing capacity are reduced since the member initial curvature exists.In different initial prestressing states,the limit load is linearly reduced with the increase of initial curvature and the relation curves between them are parallel.The proposed initial curvature element in this paper can be generally applied into the nonlinear analysis of various kinds of space grid structures,which provides more scientific accordance for the structural design.

关 键 词：弦支穹顶 初始弯曲 预应力空间网格结构 非线性稳定 极限荷载 

分 类 号：O317[理学—一般力学与力学基础] TU394[理学—力学]