无内环空间索桁结构布置方案

Layout schemes of spatial cable-truss structure without inner ring cables

基于新型索杆张拉结构——无内环空间索桁结构,运用非线性有限元法对主体索系结构布置方案进行研究.首先,总结了索网布置方案的研究现状并提出了一种研究索网方案的新思路.其次,根据膜屋盖单片膜面跨越的长度限值,提出3种索网模型:密实模型、标准模型与稀疏模型,根据新研究思路设计了3种索网方案.对比分析了3种索网方案的可行预应力分布以及荷载-节点位移曲线,论证了3种索网方案的合理性.然后,研究了3种索网方案的用钢量及对称与非对称荷载下的力学性能,并对3种方案分别进行了预应力、截面面积以及预应力对结构动力特性影响的参数分析.结果表明,索网密集程度超过一定程度不仅会导致结构总用钢量增大、造成浪费,而且没有明显改善结构的受力性能.最后,给出了无内环空间索桁结构环向等分数建议值.

Based on the new cable-strut tensile structure spatial cable-truss structure without inner ring cables(SCSWIRC),layout schemes of main cable system structure were studied.Firstly,relevant research about cable net layout scheme was summarized,and a new way of studying cable net was proposed.Secondly,according to the length limitation of single piece membrane of membrane roof,three models were proposed:dense model,standard model and sparse model.In addition,three kinds of cable net schemes were ddesigned following the proposal.The feasible prestress distribution and loaddisplacement curve of the nodes of the three cable net schemes were compared and analyzed,and the rationality of three schemes was demonstrated.Afterwards,steel consumption,force performance under symmetrical and asymmerical loads of three schemes were studied.Meanwhile,parametric analysis was conducted,including prestress,section and the influence of prestress on dynamic characteristic of the structure.The results show that the density of cable net exceeding a certain degree will lead to excessive total steel consumption of the structure,while the mechanical properties of the structure are not improved obviously.Finally,the recommended number of circumferential division for SCSWIRC was provided.