粘贴铝合金板加固钢筋混凝土梁的界面剪应力

为给粘贴铝合金板加固钢筋混凝土（Reinforce Concrete，RC）梁的铝合金板和RC梁的连接设计提供依据，对其粘贴界面剪应力开展了理论和试验研究。假设结构胶剪切变形沿厚度方向线性变化，根据粘贴界面位移协调条件，得到了一般荷载作用下的无附加锚固铝合金板加固RC梁的粘贴界面剪应力的通解。在此基础上，给出了常见荷载作用下的粘贴界面剪应力解析表达式和最大值。考虑铝合金板厚度和U形箍连接等影响因素，设计了6根铝合金板加固RC梁，对其进行了简支梁三分点加载试验。考虑铝合金板正应力和界面剪应力的关系式，通过密布在铝合金板纵轴线上的应变片测得了铝合金板的粘贴界面剪应力。根据理论计算和试验结果，得到了界面剪应力分布曲线和最大剪应力。研究结果表明：界面剪应力的理论和试验结果符合较好，呈现相同的变化规律：界面剪应力在板端取得最大值后迅速滑落至横轴附近，裂缝截面界面剪应力呈现波动。随着铝合金板厚度和板端与支座距离变大，板端界面剪应力也越大，结构胶厚度越大，最大界面剪应力越小，设置U形箍连接，界面剪应力变小。

Interfacial shear stress of reinforce concrete beam strengthened with aluminum alloy plate

The theoretical and experimental researches on the bond interfacial shear stress of the RC beams strengthened with aluminum alloy plate (AAP) were carried out, in order to provide basis for the connection design between AAP and RC beam. It is assumed that the shear deformation of structural adhesive changes linearly along the thickness direction. Then the general solutions of the interfacial shear stress of the RC beam strengthened with AAP without anchorage under general loads were obtained according to the displacement coordination condition of the bonding interface. The analytical expression and maximum value of the interfacial shear stress under several common loads were given. Considering the influencing factors such as the thickness of AAP and U-wraps connection, 6 RC beams strengthened with AAP were designed, and the three-point loading tests of simply supported beams were carried out. Based on the relationship between the normal stress and the interfacial shear stress of the AAP, the interfacial shear stresses of the AAP were got by the strain gauge densely attached to the longitudinal axis of the AAP. According to the theoretical and experimental results, the interfacial shear stress distribution curves and the maximum interfacial shear stress were obtained. The results show that the theoretical and experimental results of the interfacial shear stress distribution curves are in good agreement, showing the same change law: the interfacial shear stress quickly falls to the vicinity of the horizontal axis after reaching the maximum at the plate end. After the crack appears, the curve fluctuates at the crack. As the thickness of AAP and the distance between plate end and support become larger, the interfacial shear stress becomes also greater, the thickness of structural adhesive becomes larger, the interfacial shear stress becomes smaller, and setting U-wraps connection, the interfacial shear stress becomes smaller.