端板狗骨式连接新型部分外包混凝土柱-钢梁框架结构抗震试验研究

EXPERIMENTAL RESEARCH ON SEISMIC BEHAVIOR OF INNOVATIVE PEC COLUMN-STEEL BEAM COMPOSITE FRAME WITH END-PLATE AND REDUCED BEAM SECTION CONNECTION

为进一步研究端板狗骨式连接新型部分外包混凝土柱-钢梁组合框架结构的抗震性能,设计制作了1榀组合框架结构底部两层单跨1∶2缩尺模型试件,并对其进行水平循环往复荷载试验,记录了试验过程主要现象,得到了试件的滞回曲线。根据试验现象记录和测试数据整理记录,对试件滞回特征、水平抗侧刚度、节点连接性能、抗震延性与耗能能力、损伤进程与破坏模式等加以分析以揭示试件的抗震性能。研究结果表明：端板狗骨式连接实现了梁端塑性铰形成位置远离节点区和节点区混凝土斜压带传力模式,试件滞回曲线较为饱满,整体侧移、延性系数和等效黏滞阻尼比达到4. 03%（推）/3. 57%（拉）、3. 05（推）/2. 96（拉）和0. 280,即其变形、抗震延性与耗能能力良好;试件结构呈现梁端削弱截面和部分外包混凝土柱脚形成塑性铰的理想塑性机构,变形与耗能能力发挥充分。

To further investigate the seismic behavior of innovative partically encased concrete（ PEC） column-steel beam composite frame structure system with end-plate and reduced beam section connection,a specimen of two-story and one bay by 1/2 scale was designed and fabricated,which represented bottom two stories of composite frame. The test of the specimen was conducted under horizontal cyclic loading,experimental phenomena and hysteretic loops were derived. Based on the experimental observation and measurements, the seismic behavior such as hysteretic characteristics,lateral stiffness,behavior of connection,seismic ductility and energy dissipation capacity,damage process and failure mode were analyzed. The results verified that the plastic hinge forming location was far away from beam end and force-transfer mode of concrete equivalent strut in the panel zone was achieved due to end-plate and beam reduced section connection,the hysteretic loops of specimen was plump,its global drift,ductility and equivalent viscous damping coefficient were 4. 03%（push）/3. 57%（pull）,3. 05（push）/2. 96（pull） and 0. 280 respectively,correspondingly it owned sound deformation,ductility and energy-dissipation capacity; the ideal plastic mechanism occurred primary induced by the plastic hinges were formed in beam reduced sections at beam end and column section at bottom successively with its deformation and energy-dissipation capacity developed fully.