先斜拉后悬索组合梁自锚式悬索桥桥面板浇筑方案研究

Study on Pouring Scheme of Bridge Deck for Self-anchored Suspension Bridge with First Cable-stayed and Then Cable-suspended Composite Girder

以一拟建钢-UHPC组合梁自锚式悬索桥为工程背景,建立全桥空间有限元杆系结构模型,研究了在“先斜拉后悬索”的施工过程中,UHPC桥面板浇筑阶段、UHPC桥面板的分段浇筑方案对加劲梁受力性能的影响。研究结果表明:UHPC桥面板在临时斜拉桥成桥后浇筑,在最终成桥状态下桥面板和钢梁的受力性能均优于在吊杆张拉完成后浇筑和在斜拉-悬索体系转换完成后浇筑;在临时斜拉桥成桥后浇筑UHPC桥面板,先浇筑斜拉索区梁段后浇筑中支点附近梁段,在最终成桥状态下中跨桥面板和钢梁的受力性能均优于先浇筑中支点附近梁段后浇筑斜拉索区梁段。

Taking a proposed self-anchored suspension bridge with steel-UHPC composite girder as the engineering background,the spatial finite element member structure model of the whole bridge is established.The influence of UHPC bridge deck pouring stage and UHPC bridge deck segmental pouring scheme on the mechanical performance of the stiffening girder in the construction process of"first cable-stayed and then suspension"is studied.The research results show that the mechanical properties of UHPC bridge deck and steel beam are better when the bridge deck is poured after the completion of temporary cable-stayed bridge than those after the completion of suspender tension and after the completion of transforming the cable-stayed and cable-suspended system under the final completion state of the bridge. For UHPC bridge deck poured after the completion of temporary cable-stayed bridge, it is firstly to pour the beam segment in the stayed cable zone, and then to pour the beam segment near the central bearing point. Under the final completion stage of the bridge, the mechanical properties of mid-span bridge deck and steel beam are better than those of firstly pouring the beam segment near central bearing point and then pouring the beam segment in stayed cable zone.