铜仁市奥体中心体育馆钢屋盖施工模拟分析

Construction simulation of long-span steel roof of Tongren Olympic Sports Center Gymnasium

铜仁市奥体中心体育馆大型钢屋盖采用周边支承正放四角锥空间网格结构.因结构跨度大,施工精度要求高,不同施工方案对结构成型及落架过程中的变形及内力影响较大.为保证施工质量与施工安全,优化资源配置,根据此类大型空间网格结构常用的胎架支撑施工工艺提出两种施工方法:施工成型-结构落架搭接施工法、施工成型-结构落架顺序施工法,以及四种拆撑顺序:纵向顺次拆撑、纵向间隔拆撑、由内向外拆撑以及由外向内拆撑.在此基础上建立时变力学数值模型,通过数值仿真分析,对比不同方案施工过程中结构内力、变形、施工周期及资源消耗的差异.分析结果表明:采用施工成型-结构落架搭接施工法可大幅减少资源消耗;在合理安排拆撑顺序的前提下,不但能保证结构施工成型及落架过程中内力、位移变化平缓,而且可有效保证结构施工安全并顺利实现设计目标位形.研究成果可为类似周边支承大跨度空间网格结构施工方案选择以及施工仿真分析提供参考.

The pyramid space grid structure for the roof of Tongren Olympic Sports Center Gymnasium is constructed with peripheral supports. Due to its large span and high demand for construction accuracy, different construction schemes will have different influence on the deformation and internal forces during construction. In order to ensure safety and optimize resource allocation, this paper proposed two construction methods based on the bracket supporting construction method commonly used in space grid structures, namely construction-unloading lapping method and construction-unloading sequential method.Four unloading sequences were also proposed, involving longitudinally interval unloading, longitudinally spaced unloading, inside to outside unloading, and outside to inside unloading. Through finite element analysis, the differences in internal forces, deformation, construction period and resource consumption were compared. Results show that the construction-unloading lapping method can greatly reduce resource consumption. Under the premise of reasonable unloading sequence, not only can the internal force and displacement change smoothly during construction, but also the construction period is substantially reduced. Results from this study can provide reference for the construction of similar structures.