预应力混凝土平面杆系结构的有限元方法  

Finite element method for prestressed concrete plane frame structures

作　　者：楼铁炯[1] 项贻强 郭乙木[2] 

机构地区：[1]浙江大学交通工程研究所,浙江杭州310027 [2]浙江大学固体力学研究所,浙江杭州310027

出　　处：《计算力学学报》2005年第6期801-804,共4页Chinese Journal of Computational Mechanics

摘　　要：建立了基于有限元方法的考虑材料和几何非线性的任意截面预应力混凝土平面杆系结构的数值分析模型,可用于模拟预应力混凝土大跨度梁、单向偏压细长柱等的非线性全过程结构响应。引入修正的R odriguez截面模型确定截面切线刚度,其中混凝土的贡献通过截面边界顶点定义的梯形单元来实现;在此基础上利用传统的平面非线性杆单元导出了标准有限元公式。通过两个算例验证了该模型的可靠性和适用性。A numerical model based on the finite element method for the material and geometrical nonlinear analysis of prestressed concrete plane frame structures with arbitrary section is developed, which is capable of simulating the entire-range nonlinear response of those structures such as prestressed concrete large-span beams, slender columns under uniaxial bending, and so on. An excellent sectional model suggested by Rodriguez and Aristizabal is revised and utilized to determine the sectional tangent stiffness. The section is divided into several trapezoids according to sectional vertices. Sectional forces, i.e. axial force and bending moment, contributed by the concrete are obtained through integrating trapezoids one by one. On this basis, the standard finite element formulae are derived using the traditional nonlinear plane frame element. The element tangent stiffness matrix derived in this paper consists of three different sub-matrices accounting for material nonlinearity, material and geometrical nonlinearities, and secondary moments caused by axial force associating with structural deformation, respectively. Two numerical examples are given to verify the reliability and validity of the proposed model.

关 键 词：预应力混凝土 杆系结构 非线性 有限元方法 

分 类 号：TU378.1[建筑科学—结构工程]