【作者】 符立勇；

【导师】 罗永坤；

【作者基本信息】 西南交通大学 ， 结构工程， 2002， 硕士

【摘要】 稳定性分析问题是球面网壳(尤其是单层球面网壳)设计中最为至关重要的问题，网壳的稳定性可以从其载荷-位移全过程曲线进行分析。结构的载荷-位移曲线可以准确的把结构强度、刚度以及稳定性的整个变化历程表示清楚，我们也可以通过载荷-位移曲线研究初始缺陷和载荷分布等因素对实际网壳结构稳定性能的影响。 网壳结构的非线性问题分为几何非线性与材料非线性两个方面，由于单层球面网壳的折算厚度相对其跨度而言是很小的，因此本论文主要对单层球面网壳进行几何非线性全过程稳定性分析。 本论文在现有各种非线性稳定跟踪方法的基础上，介绍了网壳结构非线性全过程分析的理论和方法，推导了非线性空间梁单元的几何(切线)刚度矩阵，并建立了空间梁单元的非线性有限元方程。本文通过荷载-位移全过程分析对单层球面网壳结构的稳定性能进行了研究，对网壳结构的全过程分析方法作了探讨，论述了单层球面网壳结构的计算模型与载荷-位移全过程跟踪的计算方法。本文还利用大型通用有限元分析程序ANSYS对单层球面网壳结构进行了建模及求解，通过分析单层球面网壳的载荷-位移曲线，对单层球面网壳的失稳形态和稳定性能进行了比较详尽的研究，对影响单层球面网壳稳定性的多种因素进行了分析和总结，指出影响单层球面网壳稳定性的几个主要因素，并能较精确地确定单层球面网壳结构稳定性极限承载力，而且用文献[30]提出的简便计算公式进行了验证。本文的研究工作对单层球面网壳结构的稳定性设计和分析有一定的参考价值。更多还原

【Abstract】 The stability behavior is the most important respect of the design of the spherical lattice shell (especial for single-layer spherical lattice shell). The stability of the lattice shell can be analyzed by load-displacement post buckling curve. Structure’s load-displacement curve can display the whole stages of the strength, stiffness and stability clearly. We can research other factors( such as initial shortage and load apply) having the influence on actual lattice shell’s stability through the load-displacement curve.The non-linearity of lattice shell usually is divided into 2 respects : geometric non-linearity and material non-linearity. Because the computational thickness of single-layer spherical lattice shell is much smaller than the span, the geometric non-linearity post buckling stable analysis of single-layer spherical lattice shell is mainly resolved in this paper.On the basis of various current non-linearity stable track method, this paper discusses the theory and methods of the non-linear post buckling analysis on lattice shell structure , disserts the geometric nonlinear stiffness of the non-linear space beam element, and establishes the non-linear finite element equation of spatial girder unit. This paper researches the stability of the single-layer spherical lattice shell by load-displacement post buckling analysis, discusses the post buckling analysis method of the lattice shell structure, disserts the computational model of the single-layer spherical lattice shell and the computational method of load-displacement post buckling track .The paper models and resolves the single-layer spherical lattice shell by ANSYS-a large-scale current finite element analytical program. The unstable state and the stability of the single-layer spherical lattice shell has been fully researched by analyzing the load-displacement curve of single-layer spherical lattice shell. Many stable factors having influence on the single-layer spherical lattice shell have been analyzed and concluded .Several main stable factors which have influence on single-layer spherical lattice shell have been point .The stability limiting pressure of thesingle-layer spherical lattice shell has been established precisely. The calculation has been tested by the simple computational equation which has been put forward by the thirtieth reference literature. This research has some reference value for the stable design and analysis of the single-layer spherical lattice shell.更多还原