Simulation of Mechanical Properties of Bolted Joint Interface Considering Rough Surface Morphology Under Transverse Loading

Bolted joints are key fastening structures for large and complex equipment in the aerospace sector. However, under the action of transverse load, the interface will produce nonlinear phenomena such as micro-slippage and stiffness degradation, which seriously affect the reliability and safety of the equipment. In this paper, based on the KE model and Gaussian distribution, the mechanical properties of the rough connection interface of M18 bolts are simulated. Rough surfaces in simulation software are implemented by writing a Python code. Under different preloads, a lateral load is applied to the bolted structure. The initial stiffness values and force-displacement curves of the common model and the rough surface model under lateral loading were compared. The ordinary finite element model without considering rough surface has a large error compared with the model considering rough topography, and the mechanical properties of the connection structure can be better predicted through the secondary development of the model.