论文部分内容阅读
为了改善空间框架结构的几何非线性分析,根据总势能驻值原理推导了一个三维梁单元,用增量切线刚度矩阵代替传统的增量割线刚度矩阵.新的切线刚度矩阵除了常用的线性刚度和几何刚度矩阵外,还包含2个变形刚度矩阵,这2个矩阵是由每个增量步中轴力和弯距的变化引起的,是单元变形的函数,包含轴向、横向和扭转变形的耦合项.考虑空间转动和弯距的特征,增加一个修正矩阵,使提出的单元通过刚体测试,达到良好的收敛性能.实例显示使用较少的单元模拟构件仍可有效、准确地得到空间框架的轴向扭转和弯扭屈曲的非线性性能.
In order to improve the geometrical non-linearity analysis of the space frame structure, a three-dimensional beam element is deduced according to the principle of total potential energy and the incremental tangent stiffness matrix is used to replace the traditional incremental secant stiffness matrix. The new tangent stiffness matrix, in addition to the commonly used linear stiffness And the geometric stiffness matrix, it also contains two deformation stiffness matrices, which are caused by the change of axial force and bending moment in each incremental step as a function of the deformation of the unit, including axial, lateral and torsional deformation Considering the characteristics of space rotation and bending, a modified matrix is added to make the proposed unit pass the rigid body test to achieve good convergence performance.Examples show that the use of fewer unit simulation components can still effectively and accurately obtain the spatial framework The axial and torsional buckling of the nonlinear performance of buckling.