超宽、无风撑钢箱拱肋系杆拱桥稳定性分析

Stability Analysis of Super-wide No-wind Bracing Steel-box Arch-rib Bowstring Arch Bridge

市政桥梁一般桥面很宽,跨径相对较小,采用系杆拱桥若设置风撑对景观影响很大,而不设置风撑拱肋面外稳定不容忽视。对系杆拱桥稳定分析理论进行了说明,并结合工程设计案例对拱肋面外稳定进行简化计算及有限元分析,经比较,简化计算足够精确且偏于安全;对钢箱拱肋采用等效压柱法进行面内整体稳定分析。该方法可供类似桥梁设计提供参考和借鉴。

The municipal bridges are normally wide but with a relatively smaller span. For a bowstring arch bridge, the wind braces if set will have an influence on the landscape, and if not set, the out-of-plane stability of arch rib cannot be ignored. This paper explains the stability analysis theory of bowstring arch bridge, and carries out the simplified calculation and FE analysis of the out-of-plane stability of ach rib by the engineering design cases. After the comparison, the simplified calculation is accurate enough and is partial to safety. For a steel-box arch rib, the equivalent pressure column method is used for the in-plane general stability analysis, which can be referred for the design of the similar bridges.