Investigation of the 2-D Distribution Form of Bearing Stress in a Single-Bolt Single-Shear Metal-Composite Hybrid Joint

The force analysis of bolts in single-bolt, single-shear mechanical joints is a nonlinear problem that affects the calculation of flexibility and forms the basis of the calculation of the load-distribution ratio in multi-bolt joints. This paper simplifies the force analysis of bolts based on beam theory and establishes a method for determining the distribution of bolt bearing stress in a two-dimensional plane through the first derivative of the shear force of the bolt shank. Based on the good strain correlation between the finite element model and experimental results, three types of composite material layering, three total thickness variations, six metal plate thicknesses ratios, and eight levels of fastener clamping force were considered. The fitting of data indicates that linear distribution can effectively describe the majority of joint conditions. However, when the composite layer is too thick (such as S3) or the thickness of the metal plate exceeds 2.4 times the thickness of the composite plate (such as M6), uniform and linear distributions cannot be used to describe the situation.