大开口索承网格结构施工过程断索分析

Analysis of cable breaking in construction of large opening cable supported grid structure

为了研究大开口索承网格结构在施工过程中发生局部断索对整体结构的影响,以巴中体育中心为背景,考虑在50%张拉完成、90%张拉完成及100%张拉完成后出现局部断索对结构的影响。运用瞬态动力学完全积分法及单元生死技术分析不同部位的径向索断裂后的结构响应,并对断索前后撑杆受力进行分析。考虑一种以节点位移和索力变化量为基础的双因素重要性指标,来判断索的重要程度,并对其重要性排序。结果表明:随着张拉阶段的进行,结构发生断索后的响应在逐渐增大,断索发生后会出现局部失效现象,但整体结构安全;一类索到三类索的重要性逐渐降低。

In order to study the influence of local cable breaking on the whole structure during the construction of large opening cable supported grid structure,taking Bazhong Sports Center as the background,the influence of local cable breaking on the structure was considered after 50%,90%and 100%tensioning completion.The transient dynamic integration method and element birth and death technique were used to analyze the structural response after the radial cable was broken in different parts,and the stress of the strut before and after the cable breaking was analyzed.A double factor importance index based on the change of node displacement and cable force was considered to judge the importance degree of cable and rank its importance.The results show that:with the progress of the tension stage,the response of the structure after cable breaking is gradually increasing,and the local failure phenomenon will appear after the cable breaking,but the overall structure is safe.The importance of the cable from the first type to the third type is gradually reduced.