摩擦部分自复位连接组合框架层间抗震修复性试验研究

Research on the Anti-seismic Resilience of Inter-story Substructure of Partial Encased Concrete Composite Column-Steel Beam Frame with Partial Self-Centering Friction Damped Connection

为研究摩擦部分自复位连接组合框架中间层的抗震修复性,设计1榀1∶2缩尺比例PEC柱–钢梁摩擦部分自复位组合框架中间层子结构试件进行修复前后的两次抗震试验。根据试验现象和实测数据,对试件滞回性能、水平抗侧刚度退化规律、自复位功效、耗能能力等抗震性能进行了对比分析。分析结果显示:摩擦部分自复位连接可通过摩擦T形件螺栓长圆孔合理设置以实现“设计地震水平下发挥自复位连接性能和大震设计水平转化为承压型”传力模式,进而发挥主体构件材料耗能自复位性能设计理念;摩擦耗能T形件对穿螺栓和预拉杆将梁端受拉侧拉力转为对节点区混凝土的压力,实现了节点区混凝土压力带传力,且节点区加强盖板设置使得节点区混凝土处于三向受压状态,提高了混凝土强度,更好满足了“强节点”的抗震要求;在设计地震水平下,修复前后试件层间残余侧移最大值分别为0.11%和0.13%,满足了自复位结构侧移限值0.3%要求,基本实现完全复位,而在罕遇地震水平下,修复前后试件承载力均呈增长趋势,且其层间残余侧移最大值分别为0.42%和0.44%,仍小于小震层间侧移限值0.5%,试件仍具有良好的自复位功效;摩擦部分自复位连接仅通过简单修复,即可实现受力发展进程、刚度退化规律、自复位功效和损伤耗能演化机理的基本恢复,具有良好的抗震可修复性。

To investigate the anti-seismic resilience of inter-story substructure of PEC column-steel beam frame with partial self-centering friction damped connection,a specimen with 1∶2 scale was designed and fabricated,then two tests before and after renovation were conducted under cyclic lateral loading.Based on the test observations and measurements,the specimens’anti-seismic behaviors such as the hysteretic characteristics,lateral stiffness,self-centering function and energy-dissipation capacity were studied.The results indicated that rational dimension of bolt slotted hole was designed to achieve the force-transfer mechanism of partial self-centering friction damped connection at design-earthquake level and bearing-type connection was formed at maximum considered earthquake level;the force-transfer mode of concrete equivalent strut was formed in the panel zone due to pre-tension penetrating bolts and pre-tensioned bars,and reinforced gusset plate was designed to confine concrete in the panel zone,correspondingly the anti-seismic requirements of strong joint were met;when the inter-story drift arrived at the inter-story drift limit of frame structure at design-based earthquake level,self-centering functions were sound for residual drifts of inter-story were 0.11%and 0.13%,respectively,while the inter-story drift surpassed the inter-story drift limit of frame structure at maximum considered earthquake level,self-centering functions were still good for residual drifts of inter-story were 0.42%and 0.44%,respectively;with simple repairmen,the force-transfer developing process,lateral stiffness,self-centering function and evolution mechanism of energy dissipation were restored,hence the specimen owned superior anti-seismic resilience.