连续斜系杆拱滨江大桥设计与稳定性能分析

介绍了滨江大桥主结构首次采用的无风撑三跨连续斜系杆拱(左斜20°)的设计构造,定性分析了该结构的主要受力特点,阐述了稳定分析的类型,采用第1类弹性稳定分析方法,建立空间有限元计算模型,对施工阶段、成桥以及运营状态进行了稳定性能的计算分析;同时对正交和斜交、单跨和连续端横梁刚度的影响进行对比分析.结果表明:在左斜20°时,对于刚性系杆刚性拱结构体系,桥面系刚度较大,结构的失稳主要表现在拱肋的面外失稳;而单跨与连续2种体系以及正交和斜交时的稳定性相差不大,在具有较多较强内横梁情况下,端横梁刚度对拱肋的稳定性影响不明显.

Design and stability analysis of continuous skew tied-arch bridge over Bingjiang River

A tied arch bridge without wind bracing was built over the Bingjiang River,with oblique angle of 20 degree.Its main design details are described and mechanical performances are analyzed.The stability analytical types are also introduced and the first elastic stability theory is used.A space finite element model has been built to analyze the stability performances in both construction and operation stages for single span or continuous,orthogonal or oblique bridge.The influence of stiffness of the end crossing beam is also analyzed.The result shows that out-plane buckling occurs for a rigid tie and rigid arch combined bridge whose oblique angle is 20 degree towards the left sides,but the stability are similar no matter whether it is single span or continuous and orthogonal or oblique.When there are many strong inner crossing beams,the influence of the end crossing beam on arch stability becomes unremarkable.