单拱肋结合梁组合拱桥稳定分析

Stability Analysis of a Steel-Concrete Composite Tied-Arch Bridge with Combined Slab

以某单拱肋钢-混凝土结合板组合桥面系杆拱桥为工程背景,基于拱桥稳定性分析理论,采用有限元法,定量分析了桥梁施工全过程的稳定性,并系统分析了布载方式、矢跨比、钢主梁抗弯刚度、拱肋抗弯刚度、吊杆刚度等设计参数对该拱桥稳定安全系数的影响。研究结果表明:在结构体系转换过程中,稳定安全系数有明显的降低;布载方式对该桥稳定性影响不大;系杆拱桥的面内稳定性随着钢主梁的面内抗弯刚度的增加而增加;拱肋抗弯刚度的增加,可有效地增加单索面系杆拱桥的稳定性;面外稳定安全系数随着吊杆刚度的增加而降低,而面内的稳定性则有所增加;混凝土桥面板对该类桥型稳定的贡献较小。

Based on the stability theory of arch bridge, the finite element method was used to study the influencing parameters on the in-plane and out-plane stability of a steel-concrete composite tied-arch bridge with combined slab, including the load-arrangement method, the rise/span ratio, the bending rigidity of steel girder,the rigidity of rib, the rigidity of suspender. Meanwhile, stability of the bridge in construction was analysed. The results indicate that the stability is obviously reduced in the construction stage;increasing of bending rigidity of arch rib can effectively enhance the stability coefficients of in-plane and out-plane;the variation of bending rigidity of girder and suspender can also enhance, though not obviously, the stability.