带可更换保险丝典型钢框架的地震损伤控制性能研究

Study on seismic damage-control performance of typical steel frame with replaceable fuses

结构地震损伤控制保险丝(以下简称保险丝)不仅具有控制结构损伤的功能,而且更换方便,有助于加快震损结构修复速率。从结构体系角度对带保险丝钢框架的损伤控制性能进行了研究,介绍了新型保险丝的构造和工作机理,建立了带保险丝结构的数值仿真模型,并对模型进行了合理性验证。采用静力和动力弹塑性时程分析方法,研究了带保险丝钢框架的损伤机理、层间变形和失效模式。研究结果表明:带保险丝钢框架的抗震性能受保险丝性能控制,中、大震作用下,结构损伤集中于保险丝,主体构件避免受到损伤;保险丝强度阈值应小于1.00,建议取0.85;保险丝的应用可改变结构的损伤机制,其可更换功能提升了结构的可恢复性;当结构遭遇的最大层间位移角达2.1%时,更换17%的保险丝即可恢复结构功能;带保险丝高强钢框架的残余变形更小,更易修复,可恢复性得到了进一步提升。

The structural seismic damage-control fuse(hereafter:fuse)not only plays a role in controlling structural damage,but also can be replaced conveniently,which is beneficial for restoring the damaged structures.This study investigated the damage-control performance of an innovative fuse-equipped steel moment-resisting frame in terms of overall structure level.The configuration and working mechanism of the proposed innovative fuses were introduced.A numerical simulation method of structure with fuses was developed and validated.The damage mechanism,deformation and failure mode of the innovative steel frame with fuses were studied by static and dynamic elasto-plastic time history analysis.The results show that the seismic performance of the typical steel frame with replaceable fuses is controlled by the performance of fuses,and the damage is concentrated on fuses under moderate and rare earthquakes,while the main structure keeps elastic.The strength threshold should be less than 1.00,and 0.85 is recommended.The application of fuses can change the damage mechanism and improve the resilience of fuse-equipped structures.The innovative frame can be restored by replacing 17% of fuses under 2.1% story drift ratio.Less residual deformation and fewer damaged fuses occurred when using high-strength steel in fuse-equipped frames,and it is easier to recover and more resilient.