斜腹杆体外预应力结构杆索几何非线性耦合分析

采用增量线性化的分析方法,以斜腹杆体外预应力结构为研究对象,通过索单元模型的建立,应用几何关系、物理关系及平衡关系,求得索结点位移增量的结构切线刚度矩阵及腹杆伸缩增量列阵.研究表明,斜腹杆体外预应力结构切线刚度矩阵不仅与索单元杨氏模量、横截面面积、原长、当前的参量相关,还与腹杆当前的参量相关.用牛顿-拉斐逊(Newton-RaPhson)增量迭代法,对索结点位移编制计算程序.斜腹杆体外预应力结构杆索耦合的几何非线性分析,为梁-杆-索组合结构加固设计提供了理论依据.

Analysis of geometrically nonlinear coupling of poles to cable in externally prestressed structure with tilted belly poles

By means of applying the analysis method of increment linearization, taking externally prestressed structure with tilted belly poles as investigation object,and establishing cable element model, the tangential stiffness matrix of the displacement increment of the cable node and the elongation-shrinkage increment array of the belly poles are found for the structure by using its geometric, physical, and balancing relation. The tangential stiffness matrix of foregoing structure will be correlated not only with the parameters of the cable elements such as Young's modulus, cross-sectional area, original length, and current parameter but also with the current paramer of the belly pole. Newton-Raphson's increment iteration method is used to compile a computation flow of cable node displacement. The analysis of geometric nonlinearity of poles-to-cable coupling in externally prestressed structure with tilted belly poles will provide a theoretic bases for reinforcement design of combined structure with tilted belly poles.