This paper presents a new cohesive law for modelling interfaces under mixed-mode cyclic loading. The formulation is based on the definition of a free energy function which governs the interface behaviour under monotonic loading, which is then extended to cyclic-driven decohesion through the introduction of a scalar damage variable, whose evolution in time is governed by a phenomenological rate equation. The cohesive model is formulated for a mixed-mode problem and then it is applied for the simulation of debonding phenomena occurring at the interface under a pure a shear stress state. Experimental results available in literature, related to single-lap shear tests, performed on both concrete and steel specimens reinforced by fibre reinforced composite (FRP), are used to validate the proposed model and to show its effectiveness to simulate very closely the observed experimental behaviour.

本文提出了一种新的内聚定律，用于在混合模式循环载荷下建模界面。该公式基于自由能函数的定义，该函数控制单调载荷下的界面行为，然后通过引入标量损伤变量将其扩展到循环驱动的脱聚，其随时间的演变由现象学速率方程控制. 内聚模型是为混合模式问题制定的，然后将其应用于纯剪切应力状态下界面处发生的脱粘现象的模拟。文献中可用的与单搭接剪切试验相关的实验结果，在由纤维增强复合材料 (FRP) 增强的混凝土和钢试样上进行，