高墩大跨曲线刚构桥最大悬臂与成桥阶段稳定性分析

Maximum Cantilever and Phase Stability Analysis of Long-span Curve Rigid Frame Bridge with High-rise Piers

以高墩大跨曲线刚构桥为研究对象,基于欧拉稳定理论,利用空间有限元法,考虑可能的不利荷载工况,对最大悬臂状态和成桥运营阶段的结构稳定性进行计算分析.结果表明:最大悬臂状态是施工过程中最不稳定的状态;对该桥结构稳定性起控制作用的是恒载,活载、风荷载、温度等对桥梁稳定影响不大或者比较小;在悬臂浇筑阶段,曲线刚构桥墩顶的横向位移显著增大,在成桥阶段时影响较小,尤其是风荷载的影响;得出高墩大跨曲线刚构桥墩高、曲率半径与稳定特征值之间的关系,为同类桥梁的设计、施工及线性监控提供参考.

With high pier long-span curve bridge as the research object , based on Euler stability theory , with the use of the space finite element method and the consideration of possible adverse load condition , the maximum cantilever state , and the structural stability of the bridge are calculated and analyzed .The results show that：The largest cantilever state is the most unstable state in construction process; Dead load controls the stability of the bridge structure, while live load, wind load, temperature have little impact on stability;In cantilever construc-tion stage, the transverse displacement of curve rigid frame bridge pier top increases greatly , and the influence of wind load decreases;The numerical relationship among the height of the bridge pier , the radius of curvature and stability is obtained , which provides references for the design , construction and linear monitoring of similar bridges.