刚接与铰接混合连接杆系结构的几何非线性分析

本文提出用子结构原理解决具有刚接与铰接混合连接空间杆系结构的几何非线性分析，实现其非线性稳定性分析的载荷-位移全过程跟踪。该法无须单独推导刚接、铰接以及一端刚接一端铰接单元的弹性刚度矩阵和几何刚度矩阵，而可以直接由空间梁单元退化得到，而且可以将平面问题与空间问题、刚接与铰接混合连接体系进行统一处理，算例表明，本文方法对于杆系结构的统一和整体分析是有效的。

Geometrically nonlinear analysis of mixed frame structures with rigid and pinned joints

The geometrically nonlinear static analysis of mixed frame with rigid and pinned joints is studied in this paper. Sub structure method is employed to deal with the bar as a sole substructure. The element tangent stiffness matrix with different joining condition can be degenerated from three dimensional beam tangent stiffness matrix. Examples show that this method is simple and convenient for mixed frame with different joints and is prospective to be developed as a unified approach to structural geometrically nonlinear analysis of frame.