不同施工张拉方法下轮辐式索桁架力学分析与试验研究

Various Tensioning Methods and Experiment Research of Spoke Cable-truss Structure

针对圆形轮辐式索桁架结构,为研究合理安全、经济实用的施工张拉方法,确保结构成型后受力和变形与设计一致,基于分步提升整体张拉的思想,提出张拉上径向索、张拉环向索和顶升内撑杆3种施工张拉方法.对3种施工张拉方法进行施工仿真分析,研究张拉过程中的力学性能特点和发展历程.试验以1:10的结构缩尺模型,采用张拉上径向索方法、张拉环向索方法、顶升内撑杆方法对试验模型进行张拉.研究结果表明:3种施工张拉方案发展历程规律相同;施工中张拉上径向索方案所需张拉工装吨位最大,但操作简单;顶升撑杆方案工期最长,张拉环索方案张拉工装吨位最小,但需对环索进行构造处理.将张拉试验结果与理论结果进行对比分析,最后得出适合轮辐式索桁架结构的施工张拉方案,所得结论对此类预应力钢结构施工方法具有实际借鉴意义.

This paper aims at the circular spokes cable truss structure.To study the reasonable,safe,economical and practical construction tension method,and to ensure that the stress and deformation of the structure after forming are consistent with the design,based on the idea of lifting the overall tension step by step,three kinds of construction tension methods were put forward,which were radial cable,tension ring direction cable and jacking inner support bar.The construction simulation analysis of three stretching methods was carried out to study the mechanical properties and development process of the stretching process.In the test,the 1:10 scale model of the structure was adopted,and the test model was tensioned with the radial cable method,the tensioning ring directional cable method and the jacking internal brace method.The research results show that the development history of three kinds of construction tension schemes is the same.In the construction,the maximum tonnage of the tensioning workpiece is required for the scheme of tension up radial cable,but the operation is simple.The maximum construction period is the maximum and the minimum tonnage is the minimum,but the construction of the ring cable is needed.The results of tensile test are compared with the theoretical results,and the project of tensioning for spoke-and-cable truss structure is concluded.The conclusion has practical reference significance for the construction method of this kind of prestressed steel structure.