CFRP布抗弯加固钢筋混凝土梁内锁锚固体系试验研究

Experimental Study on the Flexural Behavior of RC Beam Strengthened with CFRP Strips Inter-lock Anchorage System

为了充分利用CFRP材料高强的优势,抑制加固梁早期剥离破坏,本文提出一种附加锚固措施:内锁锚固系统,并进行了6根CFRP布加固钢筋混凝土梁抗弯性能试验研究,以验证这种内锁锚固系统对早期剥离破坏的抑制效果,同时研究控制参数对加固效果(破坏特征、承载力、刚度、裂缝开展等)的影响规律。试验结果表明:这种锚固方法能阻止CFRP布的剥离向端部发展,将弯剪裂缝引起的剥离限制在局部区域内,抑制其产生滑移;可提高极限荷载10%～20%,提高抗弯刚度7%～34%,有效降低梁的裂缝宽度。通过对比,发现减小开槽间距对梁的受弯影响不大,适当增加开槽宽度可提高梁的抗弯刚度。

To take full advantage of high strength advantage of carbon Fiber Reinforced Plastic（CFRP）,and resolve the problem of the debonding failure of concrete beams strengthened with CERP,a new anchor system which CERP strips is proposed in this paper.Six reinforced concrete（RC） beams strengthened with CFRP sheets are tested to evaluate the flexural behavior.The effect of anchor system on avoiding the debonding failure is validated.Furthermore,the influence of control parameters on reinforcement effect is investigated,including failure characteristics,bearing capacity,stiffness,crack developing and so on.The results show that the anchor system can prevent the debonding of CFRP from expanding to the end of CFRP due to the crack of bend and shear loads.It means the debonding of CFRP is restricted to the local area and slippage is inhibited.Besides,the ultimate load can be increased by 10% to 20%,and bending rigidity can be increased by 7% to 34%.The crack width of beams is decreased effectively.It is found that reducing the space of grooves has little influence on bearing capacity,and bending rigidity would be properly raised due to the increase of the width of grooves.