空间拱桥结构侧倾稳定性的实用计算

A Practical Method for Lateral Buckling Analysis of Arch Bridges

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。

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.