对浙江省乐清市体育场所采用的新型月牙形空间索桁罩棚结构的施工方法进行了研究.提出一种在低空台架组装构件,并依次牵引上下径向索提升整体结构的施工方案.利用动力松弛法对体系的提升过程进行了数值模拟.从减小牵引距离的角度计算了组装台架的合理形状.分析了提升过程中体系的形状和内力变化特点,并发现局部撑杆倾倒的情况.借助于乐清市体育场罩棚结构的1∶15试验模型,依据该施工方案进行了张拉提升试验.测量了各提升步骤的环索节点坐标、环索和径向索的轴力,且与数值模拟结果相比符合良好.数值分析和试验结果表明:采用低空组装整体提升的施工方法可以实现月牙形空间索桁的有效成形,提升过程体系运动形态总体稳定.
The erection method was investigated for a novel crescent-shaped cable-truss tensile system used as a canopy structure in Yueqing Stadium,Zhejiang Province.An erection programme was suggested,in which members were assembled on a platform near the ground,and then the whole structure was hoisted by dragging the upper and lower radial cables in turn.Numerical simulation of the hoisting process was carried out using the dynamic relaxation method.A suitable shape of the erecting platform was calculated for minimizing the distance of dragging lines.The properties of the structural geometry and internal forces of members in hoisting process were analyzed,and some local struts were found to be toppled over.By means of a 1︰15 scaled model of the canopy structure of Yueqing Stadium,a hoisting experiment for the suggested erection programme was carried out.The nodal coordinates of loop cable,the axial forces of loop cable and radial cables at each hoisting step were measured,and well accorded with the numerical solutions by comparison.The results of numerical computation and model test revealed that the final design configuration of this cable-truss tensile system could be reached by the suggested erection programme.The kinematic path of the system during hoisting was stable in general.