强约束大尺寸钢筋混凝土柱抗震性能试验研究

为研究箍筋强约束钢筋混凝土柱的抗震性能，完成了6个配箍特征值0.34~0.44、截面尺寸450mm#x000d7;450mm的大尺寸钢筋混凝土柱试件的拟静力试验研究。结果表明，试件的破坏形态为压弯破坏，纵筋压曲甚至断裂，部分试件箍筋拉断，底部1倍柱截面高度范围内混凝土保护层剥落，箍筋约束核心区混凝土局部压碎。试件水平力-位移滞回曲线饱满，极限位移角达到1/39~1/33，延性系数均大于3.0。对于箍筋强约束柱，改变箍筋形式或改变箍筋肢距，对其正截面承载力及极限变形能力影响不大；相同位移往复加载由3次增加至5次，对其正截面承载力及峰值位移影响不大，但变形能力降低约15%。

EXPERIMENTAL STUDY ON SEISMIC PERFORMANCE OF LARGE SCALE REINFORCED CONCRETE COLUMNS WITH STRONG CONFINEMENT

To investigate the seismic performance of reinforced concrete columns with strong confinement, quasi-static tests on six full-scale reinforced concrete columns with stirrup characteristic values in the range of 0.34~0.44 and with section dimension 450mm#x000d7;450mm were conducted. The test results indicated that the failure modes of specimens were compression-bending; the longitudinal bars buckled in compression and even broke; several stirrups fractured. Within a height of one time of column depth above the column bottom the concrete cover spalled seriously and the confined concrete partially crushed. The lateral force-displacement hysteretic loops were plump, the ultimate drift ratios ranged from 1/39 to 1/33 and the ductility coefficients were greater than 3. Changing the stirrup types or changing the space of stirrup legs had little effects on the load-carrying capacity and ultimate deformation capacity of specimens. Increasing the number of lateral loading cycle from 3 to 5 had little effects on the load-carrying capacity and peak deformation of specimens, but led to about 15% decrease of the deformation capacity.