大跨径钢管混凝土拱桥空间几何非线性分析

Three Dimensional Geometric Nonlinear Analysis for Long Span CFST Arch Bridges

采用平均轴向应变模型在Ｌａｇｒａｎｇｅ－ＳＲ坐标系下建立的三维梁单元切线刚度矩阵，对钢管混凝土拱桥进行几何非线性分析。数值算例表明大跨径钢管混凝土拱桥变形验算控制设计，精确分析该类拱桥变形需计入材料非线性影响。

The three dimensional beam element tangent stiffness matrix which is derived from average axial strain model in LagrangeSR coordinates is used to analyze geometric nonlinearities of concrete filled steel tubular(CFST) arch bridges. Numerical example study indicates that deformation check is the decisive step of long span CFST arch bridge design, and material nonlinearities should be taken into account.