The equivalent elastic modulus, Poisson ratio, and density of bolted joint can be obtained through the fractal contact theory and weighted mean method.

The uneven distribution of contact stress of bolted joint can be obtained by adopting the finite element method and the surface mean contact stress is used to identify the parameters of nonlinear virtual material.

The experimental set-up with box-shaped specimens under equal pre-tightening force and bending moment effect is analyzed and the results show that the theoretical mode shapes are in good agreement with the experimental ones.

Due to the external load condition can alter the contact status of bolted joint, it is necessary to consider the effect of external load condition on the bolted joint for obtaining accurately analysis results.