桁梁桥的弹塑性侧倾稳定分析

ANALYSIS OF ELASTOPLASTIC LATERAL STABILITY OF TRUSS BRIDGES

本文在文献[1、2]所提出的桁梁桥弹性及弹塑性侧倾稳定分析理论的基础上,针对更一般的梯形桁梁桥,建立了新的斜桥门架节间侧倾稳定分析力学模型,提出了一种新的梯形桁梁桥侧倾稳定分析方法,对梯形桁粱桥的弹塑性侧倾稳定特性作了深入的分析研究,并与精确的空间杆系方法等进行了比较。结果表明,本文方法不仅具有很好的精度,而且计算速度快,数据输入简便。本文方法还适用于上承式矩形桁梁桥。

The problem of elastoplastic lateral buckling of steel truss bridges, especially the ones with long span, is very important and has not been perfectly solved yet.In this paper, a new mechanical model for analyzing lateral stability of inclined portal panel is established and a new finite beam element method for analyzing inelastic lateral buckling of trapizoidal truss bridges,which are commonly used in practice, is proposed.With the aid of the method,a thorough investigation of the inelastic lateral stability has been made. In order to make sure of the reliability of the method, it has been checked against the finite element method of space bar system. The results show that the suggested method not only can give a sufficient accuracy,but also has the advantages of less amount of computation work and convenience of datain.The method can also be applied to the rectangular truss bridges without inclined portal and distortion of the cross section.