空间拱桥结构侧倾稳定性的实用计算

本文用能量原理分析了拱面具有倾斜角a的空间组拼拱肋结构在竖向均布荷载作用下的侧倾稳定性,导出了这类结构稳定临界力的近似解析解,并讨论了倾斜角a和横撑的刚度是如何影响结构侧倾稳定性的,从而可以合理地布置横撑和选择倾斜角a,以提高结构的稳定安全度。同时,本文还以有限元计算结果为基础,提出了拱面具有倾斜角a的空间组拼拱肋结构由于吊杆引起的非保向力效应的计算方法。最后,本文以大洋河桥为原型桥进行了模型试验,以验证计算方法的正确性。

A Practical Method for Lateral Buckling Analysis of Arch Bridges

This paper deals with the lateral buckling analysis of the space arch structure, composed of double main arch ribs with inclination and transverse bracings. The elastic critical buckling load q of this kind of structures is deduced according to the principle of minimum potential energy. The influences of inclination and the stiffness of bracing beams on the lateral stability of struc-ture are studied. Based on the results of finite element analysis, a practical method is proposed to evaluate the effects of non-conservative direction of hangers, and the theoretical results is in good agreement with the experimen-tal one.