延性交错桁架钢框架双角钢组合截面弦杆在往复弯曲下的滞回性能研究

发布时间：2018-06-06 16:10

本文选题：延性交错桁架 + 双角钢组合截面　；参考：《西安建筑科技大学》2017年硕士论文

【摘要】：混合式交错桁架结构在往复荷载作用下,常表现为斜腹杆的压屈或拉断,结构延性差,课题组提出延性交错桁架结构体系的概念,即通过合理设计方法将空腹节间弦杆设计为延性区段,结构其余部分保持弹性,利用延性区段屈服耗散地震能量,从而提高结构整体抗震性能。延性区段弦杆的延性及耗能能力是延性交错桁架结构抗震设计的关键。为研究延性交错桁架钢框架双角钢组合截面弦杆在延性区段的抗震性能,对8个双角钢组合截面足尺试件进行低周往复加载试验,考察了填板间距、加劲肋布置及补强钢板设置等因素对构件滞回性能的影响,同时建立了往复弯曲下双角钢组合截面构件恢复力模型。结果表明:减小填板间距可保证双肢更好协同工作,提高试件的转动能力;布置加劲肋并减小其设置间距可有效缓解板件屈曲,提高试件延性及耗能能力;增设补强钢板可转移塑性铰发生位置,改善试件的延性及转动能力;同时,角钢腹板在连接部位过早断裂的破坏模式致使其延性和耗能能力不足。本文提出的恢复力模型可以良好的表达延性交错桁架钢框架双角钢组合截面弦杆的承载力及刚度退化等特征,可为结构的弹塑性分析提供参考。研究丰富了延性交错桁架钢框架结构抗震性能的研究成果,也为双角钢组合截面受弯构件的其他工程应用提供参考。
[Abstract]:The composite staggered truss structure under reciprocating load is usually shown as bending or breaking of inclined web bar, and its ductility is poor. The concept of ductile staggered truss structure system is put forward by our research group. In other words, the hollow Internode chord is designed into ductile section by reasonable design method, the rest of the structure remains elastic, and the seismic energy is dissipated by yielding in the ductile section, thus improving the overall seismic performance of the structure. Ductility and energy dissipation capacity of chord in ductile section are the key to seismic design of ductile staggered truss structure. In order to study the seismic behavior of double angle steel composite section chord of ductile staggered truss frame in ductility section, the low cycle reciprocating loading test was carried out on 8 full-scale specimens with double angle steel composite section, and the spacing of filling plates was investigated. The effects of stiffener arrangement and reinforcement plate setting on the hysteretic behavior of the members are discussed. The restoring force model of the members with double angle steel composite section under reciprocating bending is established at the same time. The results show that reducing the spacing of the fill plate can ensure the joint work of the two legs and improve the rotation ability of the specimens, and the stiffening ribs and the space between the stiffeners can effectively alleviate the buckling of the plates and improve the ductility and energy dissipation capacity of the specimens. The location of plastic hinge can be transferred by adding reinforced steel plate, and the ductility and rotation ability of the specimen can be improved. At the same time, the failure mode of premature fracture of angle steel web leads to insufficient ductility and energy dissipation. The restoring force model presented in this paper can well express the bearing capacity and stiffness degradation of ductile staggered truss steel frame string with double angle steel composite section, which can provide a reference for the elastoplastic analysis of the structure. The study enriches the research results of seismic behavior of ductile staggered truss steel frame structures, and provides a reference for other engineering applications of flexural members with double angle steel composite section.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU391;TU352.11

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