轮辐式交叉索结构构形研究及其预应力态分析

以传统轮辐式索结构为基础，提出一类轮辐式交叉索结构，该类结构由双层外环压梁、双层内环拉索、内环撑杆、径向交叉布置的径向承重索、径向稳定索及它们之间的联系索杆组成。采用径向索交叉布置的新形式可减小结构层高度，改善结构整体抗扭刚度，同时形成的“空间谷脊效应”便于屋面组织排水。根据内环撑杆布置方式的不同，轮辐式交叉索结构又可分为竖撑杆型和人字撑杆型两种不同构形的轮辐式交叉索结构。基于节点平衡方程，对提出的两种轮辐式交叉索结构进行预应力态分析，推导出轮辐式交叉索结构预应力态内力的计算公式。此外还将轮辐式交叉索结构的预应力态受力特性与传统轮辐式索结构进行对比，并考虑不同内环结构高度、内外环几何中心高差等几何参数下结构的自应力分布情况。结果表明，轮辐式交叉索结构具有结构高度低、结构刚度大、受力合理等特点，在大型体育场等建筑中有很好的工程应用前景。

Study on structural types and prestressing force distribution of wheel-spoke crossed cable structures

A new type of spatial cable-strut structure called wheel-spoke crossed cable structure (WSCCS), which is originated from traditional wheel-spoke cable structure (WSCS), is proposed. WSCCS is composed of two-layer outer looped beams, two-layer inner looped cables, inner looped struts, crossed radial bearing cables, crossed radial stable cables, and linked cables (or struts). The crossed radial cables can decrease the structural height, and increase the torsional rigidity. Also spatial valley effect caused by these cables in WSCCS shall be beneficial to roof drainage. Based on different structural forms for inner looped struts, WSCCSs can be divided into two different structural types, which are, WSCCSs with vertical struts and WSCCSs with herringbone struts. Analysis on prestressing force distribution of WSCCSs is conducted based on the equilibrium equation of each nodal point, and some calculation equations are derived. Moreover, the mechanical characteristic of WSCCSs are compared with that of WSCSs under prestressing condition, considering different structural height of inner loop and different height difference between inner loop and outer loop. The results show that WSCCSs have those characteristics such as small structural height, good global structural rigidity and reasonable load carrying path, indicating that WSCCSs have broad application prospects in stadiums.