为了提出HB-FRP加固体系的粘结滑移模型,将HB-FRP的抗剪作用分为混凝土楔体摩擦及钢钉销栓作用两部分开展研究。假定钢扣件下方混凝土的损伤形态为楔体滑移,对混凝土楔体进行分区应力状态分析,建立了混凝土楔体的粘结滑移模型。为了便于工程推广应用,提出了简化的混凝土楔体粘结滑移计算模型,研究了混凝土强度对简化模型特征参数的影响,通过大量参数分析,得到了简化模型的特征参数。基于HB-FRP单剪破坏试验,建立了数值有限元模型以验证所提出粘结滑移模型的有效性。研究结果表明:所提出的粘结滑移模型考虑了混凝土强度、钢扣件尺寸等参数,在分析HB-FRP加固混凝土结构破坏过程时具有较高的精度;HB-FRP加固方法的有效粘结长度比普通FRP的大。
In order to present the bond-slip model for HB-FRP systems, HB-FRP shear effect w~:sdivided into two parts: concrete wedge friction and dowel action of nails. The concrete failuremode under steel fasteners was assumed as wedge slip, the stress of wedge body was analyzed bypartitioning, and bond-slip model of concrete wedge was established. In order to facilitateengineering application, simplified concrete wedge bond-slip model was proposed, effect ofconcrete strength on the model parameters was analyzed. Through a large number of parametersanalysis, simplified model parameters were got. Based on HB-FRP single shear failure tests,numerical finite element model was established to verify the effectiveness of the proposed bondslip model. The results show that the model considers the strength of concrete, steel fastenerdimensions and other parameters, and the proposed bond-slip model can accurately predict thefailure process of concrete structures reinforced with HB-FRP. The effective bond length of HBFRP is larger than that of FRP.