Abstract
Evaluation of the natural frequency and the natural mode of vibration of a bolted joint is particularly important to avoid the failure of the structure due to the resonance. The vibration characteristics of a bolted joint are largely influenced by such factors as the surface roughness of contact surfaces, the magnitude of axial bolt force, the arrangement of claming bolts, etc. In this paper, natural frequencies of the bending vibration of a bolted joint with simple configuration are measured with strain gages mounted on the surface of test specimen, and the effects of surface roughness, axial bolt force and bolt position are systematically investigated. Then, a numerical procedure is proposed to analyze the free vibration problem of a bolted joint, where the effect of interface stiffness due to surface roughness is incorporated into the finite element formulation. It is also presented that the computation efficiency for solving the eigen value problem can be fairly improved by introducing selective reduced integration (SRI) scheme. The effectiveness of the numerical procedure proposed here is validated by experimental measurements of the natural frequencies of the first mode.
