钢桁梁柔性拱桥极限承载力分析

Analysis on the Ultimate Bearing Capacity of the Flexible Arch Bridge with Steel Truss Beam

根据连续介质力学基本理论,针对大跨度钢桁梁柔性拱桥在变形、失稳破坏期间产生的材料和几何非线性特性,用通用软件ANSYS建立桥梁的空间模型。采用非线性有限元法,进行钢桁梁柔性拱桥在两种不同加载情况下的极限承载力分析。结果表明,桥梁局部变形失稳是影响整体极限承载力的重要因素。提出通过增大个别杆件的刚度来提高极限承载力的方法。

According to the basic theory of continuum mechanics and considering the nonlinear characteristics of material and geometry during its deformation and instability for long-span flexible arch bridge with steel truss beam, the spatial model of the bridge was established by a general-purpose software ANSYS. The analysis on the ultimate bearing capacity of flexible arch bridge with steel truss beam under two different loading conditions was carried out by adopting nonlinear finite element method. The result shows that the main factors affecting the ultimate capacity are the local deformation and instability of the bridge. The paper proposes the method for improving the ultimate capacity by increasing the rigidity of specific members.