IDENTIFICATION OF NONLINEAR INTERFACE MODELS

A nonlinear model for joints interfaces is proposed capable of representing the dominant physics involved in a mechanical joint such as micro/macro slip. The joint interface is modelled using a combination of linear and cubic springs. The coefficient of nonlinear spring is assumed to be complex to simulate the softening as well as damping effects of the joint during slipage. An estimate of the response of the structure with the joint under external excitations is obtained using the method of multiple scales. The parameters of the model, i.e. the spring constants are functions of normal and tangential stresses at the joint interface and may be identified by minimizing the difference between the obtained qualitative nonlinear solution and the experimentally measured data.

Keywords:

Joint interface model , Micro slip , Method of multiple scales