高轴压比下PVA-ECC柱抗震性能试验研究

设计了3根PVA-ECC柱进行低周反复加载试验，分析了高轴压比下配箍率变化对柱抗震性能的影响，并与普通钢筋混凝土柱进行对比，分析其在滞回性能、延性、耗能性能及刚度退化上的差异.结果表明：3根PVA-ECC柱在低周反复荷载作用下均发生弯曲破坏，没有出现普通钢筋混凝土柱的劈裂、剥落与黏结破坏；随着箍筋间距的减小，抗震延性得到改善，箍筋间距70 mm和50 mm的柱与间距90 mm的柱相比，位移延性、极限弹塑性位移角、等效黏滞阻尼系数分别增加了15.6%～16.3%，17.1%～20.6%和15.6%～17.8%；最后给出了满足一定位移延性和极限弹塑性位移角的抗震设计要求的最小配箍率的建议值.
In this paper, the low reversed cyclic loading tests of three PVA-ECC columns were carried out, and the influence of the stirrup ratio change on the seismic performance of the columns under the high axial load ratio was studied, and the hysteretic performance, ductility, energy dissipation capacity and stiffness degradation of the test PVA-ECC columns and the ordinary reinforced concrete columns were compared. The test results indicate that, under high axial load, the test specimen exhibited flexure failures with better ductility, and bond splitting, spalling of ECC as well as composite disintegration due to cyclic loading were prevented. With the decrease of the stirrup spacing of PVA-ECC columns, the seismic ductility was also improved greatly. Compared with the PVA-ECC column with stirrup spacing( 90mm),the displacement ductility, the maximum drift ratio and the equivalent viscous damping ratios of the PVA-ECC columns with stirrup spacing 70 mm and 50 mm were improved by 15.6%～16.3%,17.1%～20.6% and 15.6%～17.8%, respectively. Minimum stirrup ratio that can satisfy certain seismic requirement on displacement ductility and drift ratio were put forward.