轮辐式单-双层混合索网结构成形关键技术研究

Research on key technology for formation of spoke tension structure with single-double-combined layer cable

为研究适用于体育场建筑的大开口轮辐式单-双层混合索网结构成形关键技术,以乐山奥体中心体育场为研究对象,介绍了结构构形,分析了自重与预应力作用下结构的力学特点,提出了整体牵引提升、分批张拉锚固的总体成形方法,并采用非线性动力有限元分析方法,对比优选了径向索张拉的最后锚固批次和双层索网撑杆的安装时机,进行了全过程张拉成形分析。结果表明:混合索网结构与单层和双层索网结构受力特点存在较大差异,径向索索力最大值出现在单层索网区域两侧,索夹两侧环索索力最大差值出现在单双层交界处;为减小径向索张拉锚固力值和索夹两侧环索索力差值,确定径向索的分批张拉锚固顺序为上径向索、单径向索、下径向索,并确定在分批张拉锚固上径向索之后,张拉锚固单径向索之前安装撑杆;全过程张拉成形分析结果验证了成形方法的有效性和安全性,研究成果已成功应用于实际结构中。

Aiming at the key technology for the formation of large opening spoke tension structure with single-double-combined layer cables suitable for stadium building, Leshan Olympic Center Stadium was taken as the research object, the structural configuration was introduced and the mechanical characteristics of self-weight prestressed state were analyzed. The whole construction method including overall traction lifting, batch tensioning and anchoring was proposed. By using nonlinear dynamic finite element analysis method, the final anchoring batch of radial cable tensioning and the installation time of double-layer cable net struts were compared and optimized, and the whole process of construction analysis was carried out. The results show that the mechanical characteristics of spoke tension structure with single-double-combined layer cables are quite different from that of single-layer and double-layer cable net structures. The maximum radial cable force appears on both sides of the single-layer cable net area, and the maximum difference between the ring cable forces on both sides of the cable clip appears at the junction of single and double layers. In order to reduce the force value of radial cable tensioning and anchoring, as well as the difference between the ring cable forces on both sides of cable clamp, the batch tensioning and anchoring sequence of the radial cable is determined, to be upper radial cable, single radial cable and the lower radial cable. It is also determined that after the upper radial cable is tensioned and anchored in batches, the brace can be installed before the single radial cable is tensioned. The analysis results of whole construction process verify its effectiveness and safety of the construction and forming method, which has been successfully applied in practical structure.