通过3片砌体墙试件的水平低周往复加载抗震试验,研究喷射玻璃纤维聚合物加固和粘贴碳纤维布加固开窗洞无筋砌体墙的抗震性能.通过分析各墙片的破坏形态、抗震抗剪承载力、滞回特性、刚度退化及耗能能力,比较2种不同的纤维增强聚合物加固方案对开窗洞砌体墙片的抗震加固效果.试验结果表明,采用喷射玻璃纤维聚合物加固试件的极限承载力、延性系数和耗能系数较未加固试件分别提高223.8%,125.4%和5.6%,其抗剪承载力提高幅度、对抗震性能的改善以及保障洞口安全方面均优于粘贴碳纤维布加固方法;喷射玻璃纤维聚合物加固层可以与砌体有效粘结,协同工作,发挥显著的抗震加固效应.
Through the seismic experiments of three masonry wall specimens subjected to the horizontal cyclic loading combined with a constant gravity load,the seismic behaviours of unreinforced masonry walls with window openings strengthened with sprayed glass fibre reinforced polymer(GFRP) and epoxyed carbon fibre reinforced polymer(CFRP) sheets are investigated.The seismic strengthening effects by two different FRP retrofitting schemes are compared in terms of the failure modes,seismically shear capacity,hysteresis characteristic,deterioration of rigidity and energy dissipation ability of each specimens.The experimental results indicate that compared with the unstrengthened specimen,the ultimate capacity,the ductility factor and the energy dissipation coefficient of the specimen strengthened with sprayed GFRP are increased by 223.8%,125.4% and 5.6%,respectively;the increasing degree of shear capacity,the improvement of seismic behaviour and the guarantee of opening safety are significantly superior to that of the specimen strengthened with epoxy-based CFRP;and the overcoat of sprayed GFRP can bond tightly and work well together with the masonry,which can play a critical role in earthquake resistance.