基于弧长法的预应力框架结构非线性分析

根据后张有粘结预应力混凝土框架结构的受力特点，编制了适用于预应力建立和施加外荷载两个阶段的静力杆件非线性有限元分析程序．该程序直接从材料的应力一应变关系出发，考虑了混凝土的受拉硬化和受压软化，采用截面分层杆系有限元模型和弧长法，在刚度矩阵中同时考虑了材料非线性和几何非线性．经与两榀预应力混凝土框架试验结果校核，程序模拟精度较好，可用于后张有粘结预应力混凝土框架结构的计算与分析．

Nonlinear Analysis of Prestressed Frame Based on Arc-Length Method

According to the loading characteristics of bonded post-tensioned prestressed concrete frames, a program is worked out to perform a nonlinear finite element analysis for the static staff in both the stretching wire stage and the loading stage. In working out the program, the relationship between the stress and the strain of the material is directly employed, the tension hardening and compression softening of concrete are considered, the sectional lay- ered finite element model and the arc-length method are adopted, and both the material nonlinearity and the geometric nonlinearity are taken into account in the stiffness matrix. As compared with the experimental results of two prestressed concrete frames, the simulated results obtained by the program are of high precision, meaning that the proposed program is suitable for the calculation and analysis of bonded post-tensioned prestressed concrete frames.