劲性骨架混凝土拱桥外包混凝土分环浇筑方案对结构受力的影响

Influence of Pouring Cycle Schemes of Externally Wrapped Concrete of Concrete Arch Bridge with Stiff Skeleton on Structure Mechanics

以在建广安官盛渠江特大桥为研究对象,采用Midas/Civil 2015分别建立4个不同分环方案的有限元模型,并进行了完整的施工阶段计算。探讨了在拱圈外包混凝土浇筑过程中,不同分环浇筑方案对结构受力的影响。发现分环数量对劲性骨架及外包混凝土应力均有明显影响;分环越多,劲性骨架应力变化越平缓,其应力越小;m_1的大小对外包混凝土应力影响较大,在满足劲性骨架承载力、稳定性及施工安全要求的前提下,m_1值越大,外包混凝土的应力越小。最后,从兼顾施工速度及结构受力角度提出了一些建议。

Taking Guansheng-Qujiang River Grand Bridge in construction in Guang＇ an as the research object, Midas/Civil 2015 was used to establish the finite element models of four different pouring cycle schemes respectively, and the complete construction process was calculated. The influence of different pouring cycle schemes on the structure mechanics during the externally wrapped concrete pouring process outside arch ring was discussed. It is discovered that the pouring cycle number will significantly affect the stress of stiff skeleton and the externally wrapped concrete. The greater the number, the gentler stress change and the less the stress of stiff skeleton. And the influence of the value of m1 on the stress of externally wrapped concrete is obvious. On the premise of meeting the bearing capacity, stability and construction safety, the greater the value of m1 , the less stress of the externally wrapped concrete is. Finally, some suggestions are given in view of the construction speed and the stress of the structure.