拉拔条件下GFRP筋与混凝土粘结强度试验研究

采用Canadian Standards Association(CSA)标准规定的拉拔试验方法,考虑GFRP筋的种类、组分、直径、表面处理方法、肋间距、肋高度、肋宽度等因素,对GFRP筋与混凝土之间的粘结强度进行了试验研究。研究结果表明:试件的粘结破坏有筋表面变形的剪切、变形的脱落和肋间混凝土被剪碎三种形式;GFRP筋与混凝土的粘结强度低于钢筋与混凝土的粘结强度,大约为钢筋与混凝土粘结强度的65%~87%;GFRP筋的种类、直径、表面处理方法、肋高度、肋间距和肋宽度等因素对粘结强度的影响显著,但GFRP筋组分的影响不大;当肋间距为GFRP筋直径、肋高度为GFRP筋直径的6%时,GFRP筋与混凝土的粘结强度最高。

Experimental investigation on bond strength between GFRP rebars and concrete under pullout conditions

Based on the Canadian Standards Association(CSA) criterion,pullout test was used to study the effect of rebar type,rebar component,rebar diameter,rebar surface texture,rib height,rib spacing and rib width on the bond strength between GFRP rebar and concrete.Test results show that there are three failure modes,namely deformation shearing off,deformation desquamation and the crush of the concrete between the ribs.The bond strength of GFRP rebars is about 13-35 percent lower than that of steel rebars.The rebar type,rebar diameter,rebar surface texture,rib height,rib spacing and rib width has significant effects on the bond strength while the rebar component showed little.The highest bond strength is obtained when rib spacing equaled rebar diameter and rib height is 6 percent of rebar diameter.