高强钢组合K形偏心支撑框架抗震性能对比分析

为研究不同强度组合的高强钢组合K形偏心支撑框架结构的抗震性能，设计了一组不同强度(Q345、Q460、Q690钢材)组合的5层K形偏心支撑框架结构算例Q345-5、Q460-5和算例Q690-5，选取10条地震动记录对其进行动力时程分析，得到各算例在不同水准地震作用下的耗能梁段转角和层间位移角。研究表明：8度罕遇地震作用下，高强钢组合K形偏心支撑框架的层间位移角比传统K形偏心支撑钢框架大，各算例耗能梁段全部进入塑性变形阶段；塑性层间位移角到达规范限值时，算例Q460-5框架梁开始进入塑性变形阶段，算例Q690-5框架柱、框架梁和支撑均处于弹性变形阶段，还可以承受更大的地震作用；达到定义的极限状态时，与传统偏心支撑钢框架相比，算例Q460-5能够承受的地震作用和耗能梁段转角更小；算例Q690-5承受的地震作用和耗能梁段转角更大。

Comparative analysis on seismic performance of high strength steel composite K-shaped eccentrically braced frames

To study the seismic performance of high-strength steel composite K-shaped eccentrically braced frames (K-HSS-EBFs) with steels of varying strengths, three 5-story K-HSS-EBFs with different combinations of steel strength were designed with Q345-5, Q460-5, and Q690-5 steels. The dynamic time-history analysis was performed using 10 seismic ground motions. The rotation angles of links and inter-story drift ratio of the samples at different levels of earthquake were obtained. The results show that under 8-degree rare earthquakes, the inter-story drift ratio of the K-HSS-EBFs is larger than that of the conventional K-shaped EBF, and the links of all samples enter the plastic deformation stage. When the plastic inter-story drift ratio reaches the specification limit, the frame beams of Q460-5 begin to enter the plastic deformation stage. In contrast, the frame columns, frame beams and braces of Q690-5 are found to be in the elastic deformation stage for such earthquakes and can withstand greater seismic action. In the limit state, compared with the conventional K-shaped EBF, the seismic impact that the structure could withstand and the link rotation angle obtained with Q460-5 are smaller, while in the case of the Q690-5 samples, they are larger.