Dynamics Model of Bolted Joint Based on Uneven Pressure Distribution of the Surface

In this paper, a dynamics model based on the surface uneven pressure distribution was presented for the bolted joint because the surface contact pressure of bolted joint is uneven distribution due to the influence of concentrated force of multi-bolts. The contact surface of bolted joint was assumed to be flat in macro-scale and the pressure distribution can be obtained by the FEM. The contact surface of bolted joint was rough surface in micro-scale, and the normal and tangential stiffness damping model based on the surface contact pressure was presented for the bolted joint using fractal contact theory. An experimental set-up with box shape specimen was designed for validating the presented model. The natural frequencies and frequency-response function can be obtained by modal testing. Compared with simulation result, the presented model can be used to accurately predict the dynamic characteristic of bolted joint.