Interfacial shear stress analysis in single-lap adhesive joints with similar and dissimilar adherends under dynamic loading

Single-lap joints (SLJs) with similar and dissimilar adherends are extensively used in industrial applications. This paper aims to investigate the interfacial mechanical behavior of SLJs subjected to dynamic loading. The shear-lag model is employed to predict the mechanical behavior of SLJs. The analytical expressions of the interfacial slip, normal stress in the adherends and interfacial shear stress are derived for the SLJs with similar adherends by using the method of separation of variables. The Laplace transform method is applied to numerically simulate the dynamic response of SLJs with dissimilar adherends. Results obtained from the finite element simulation are consistent well with the predictive model. It is found that the more unbalanced the SLJ is, the more non-uniform distribution of interfacial stress is, thus reducing the load-bearing capacity of the SLJ. This inspires us to rationally design a balanced joint to improve the load-bearing capacity. While the emphasis of the present study is on the mechanical behavior of SLJs, the analytical model is equally applicable to the interface analysis of other structures (e.g. concrete-steel bar, fiber-matrix in the composites, etc.). Furthermore, this theoretical method can be also simplified to explain the stress transfer subjected to the (quasi-)static loading with approximately zero density or zero loading speed in the governing equation.