Modeling method for bolted joint interfaces based on transversely isotropic virtual materials

摘要

To improve the modeling precision of bolted joint interfaces, an improved transversely isotropic virtual materials model is proposed by introducing a calculation method of elastic modulus of composite materials. The joint interface is regarded as a transversely isotropic virtual material that is rigidly linked to two components with a rotation axis parallel to the normal direction of the interface. The elastic and shear moduli of micro-contact asperities are deduced using Hertz contact theory and fractal geometry. Using the calculation method for a composite, the elastic and shear moduli of the entire joint interface were determined, which enabled the parameters of transversely isotropic virtual material to be determined. The theoretical results obtained using this transversely isotropic virtual material model were compared with experimental ones by comparing the mode shapes qualitatively and the natural frequencies quantitatively. The theoretical shapes of the vibration modes were consistent with the experimental ones, and the errors of the natural frequencies were no more than 5%. Compared with the conventional modeling method for bolted joint interfaces, the modeling precision was greatly improved.