外倾式拱桥稳定性研究

Research on stability of external slanted arch bridge

以某外倾式拱桥为工程背景,建立该桥的空间有限元计算模型,分4个工况计算了该桥的稳定安全系数,通过改变拱肋外倾角度、拱肋刚度、端横梁刚度以及吊杆布置形式计算了不同设计参数下结构在恒载工况以及恒载+活载工况的失稳特征值,结果表明,拱肋的刚度对稳定性起着决定性作用,吊杆的布置形式只改变拱肋的面内刚度,对于面外刚度没有影响。

Taking some external slanted arch bridge as the construction background, the paper establishes the space finite dement calculation model of the bridge, calculates the stability and safe coefficient of the bridge by four working conditions, and counts the instability characteristics value of different design coefficients at the dead load and at the dead load plus the live load by changing the out-inclined arch rib angle, the rib rigid, the end cross beam rigid and the suspender layout forms. It is shown by the result that the rigid of the arch rib plays the decisive role, while the suspender layout forms only change the in-plane stiffness and it has no influence on the out-of plane stiffness.