铝合金板与混凝土的粘贴粘结强度研究

为了在提高加固钢筋混凝土梁承载力的同时具有很好的延性和耗能能力，特别是满足侵蚀环境及寒冷环境中加固工程的需要，采用铝合金板加固钢筋混凝土梁是一个很好的解决办法。铝合金板通过粘贴层将力传给钢筋混凝土梁，故铝合金板与混凝土的粘贴粘结性能决定了铝合金板加固钢筋混凝土梁的效果。铝合金板与混凝土的粘贴粘结强度作为铝合金板加固钢筋混凝土梁连接设计的基础，对其开展试验和理论研究。开展105个试件的铝合金板与混凝土面内单剪试验发现：对粘贴界面没有进行粗糙处理的试件发生了界面剥离破坏，其他试件均发生了混凝土层剥离破坏；界面剥离破坏的粘结性能远差于混凝土层剥离破坏，说明了对粘贴界面进行处理的必要性。通过试验得到铝合金板和混凝土连接的极限粘结荷载，根据铝合金板正应力的变化率与粘贴界面剪应力的关系，得到剪应力的分布曲线和有效粘结长度；假设剪应力沿有效粘结长度处处相等，得到了铝合金板与混凝土的粘贴试验粘结强度，并基于此讨论了界面处理、混凝土强度、铝合金板宽度、厚度和粘贴长度等因素对试验粘结强度的影响。结合试验数据的统计回归分析，提出计算铝合金板与混凝土的粘贴粘结强度的修正Niedermeier模型，得到了铝合金板与混凝土的有效粘结长度和粘贴粘结强度的理论计算公式，其理论值和试验值吻合较好，误差最大值为8.98%，平均值为0.004，标准差为0.041。研究成果为铝合金板加固钢筋混凝土梁的粘贴设计提供了理论基础。

Study on Interfacial Bond Strength Between Aluminum Alloy Plate and Concrete

RC beam strengthened with aluminum alloy plate is a good solution for the purpose of increasing bearing capacity of concrete beam. At the same time, the ductility and energy-dissipating capacity will also be better, especially satisfying the reinforcement engineering at erosion and cold environments. As the stress of aluminum alloy plate is transmitted to the RC beam through the bonding layer, the strengthening effect of the RC beam strengthened with aluminum alloy plate is determined by the bonding property between aluminum alloy plate and concrete. As the study foundation of RC beam strengthened with aluminum alloy plate, the experimental and theoretical studies on interfacial bond strength between aluminum alloy plate and concrete were given. In-plane shear tests of 105 specimens were carried out. Specimens which were not treated on the bonding interface were failured in the form of interfacial debonding. The other specimens were failured in the form of being stripped of concrete layer. The bonding property of the interfacial debonding was much worse than the stripping of the concrete layer, indicating the necessity of treating on the bonding interface. The ultimate bond loads between aluminum alloy plate and concrete were got. Shear stresses distribution curves and effective bond length were obtained according to the relationship between the change rate of normal stress of aluminum alloy plate and interfacial shear stress. Assuming that the shear stress is the same along the effective bond length, the bonding strength between aluminum alloy plate and concrete was obtained. The influencing factors on interfacial bond strength, such as interface treatment, concrete strength, width and thickness of aluminum alloy plate and bonding length, were discussed. Based on statistics regression analysis of experiment data, the modified Niedermeier model of interfacial bond strength between aluminum alloy plate and concrete was put forward. The theoretical calculation formula on effective bond length and bonding strength was obtained. The theoretical values of bonding strength are in good agreement with the testing values. The largest error is 8.98%, the average error is 0.004, the standard deviation is 0.041.