叠合梁斜拉桥混凝土桥面板滞后浇筑湿接缝的工序研究

Research on Working Procedure of Lag Pouring of Wet-joint in Bridge Deck Concrete Slab on Composite Girder of Cable-stayed Bridge

叠合梁斜拉桥施工工序繁多,最终的成桥状态与施工过程密切相关。以一大跨度叠合梁斜拉桥为对象,采用空间有限元软件建立精细化力学模型,对比分析了混凝土桥面板湿接缝不滞后、滞后1次及滞后2次这3种施工工序对桥梁结构在施工过程及成桥的受力影响。结果表明,滞后1次及滞后2次的工序下桥面板几乎不出现拉应力,而随着桥面板滞后次数的增加,钢主梁的压应力显著增大,选择桥面板滞后1次的施工工序,结构在施工过程中及成桥运营阶段的受力最佳,同时工期也较短。

Construction procedure is complicated for cable-stayed bridge using composite beam. Final state of bridge depends on construction greatly. In the article,a large span cable-stayed bridge was studied. The bridge 3D finite element model was established to analyze the effect of working procedure during construction and at completion. Three working procedures were studied： no lag pouring,one lag pouring and twice lag pouring of wet-joint of concrete slab. The analysis results indicate that tensile stress in concrete slab is small for one/twice lag pouring. But, as lag times increase,compression stress in steel girders increases significantly. One lag pouring is best for structure stress in the construction process and operation stage,and the construction period is short.