No abstract

In this paper, detailed instructions are given for performing static reduction on a finite element description of an elastic contact problem, thus reducing the dimensionality of the problem to the set of contact nodes alone. This significantly reduces the computational time for the solution to evolutionary contact problems and also gives the user greater control over the detailed implementation of the contact and friction laws. The reduced stiffness matrix is also an essential ingredient in the determination of the critical coefficient of friction for the problem to be well posed, and it facilitates the determination of the conditions under which a frictional system may shake down under periodic loading.

In this article, we consider the interfacial characteristics of a lap joint formed using friction grip bolts. The joints consist of two elastically similar laps pressed in contact by a constant normal force and subjected to oscillatory bulk load at the free end of the laps. It is found that application of the normal load causes the contact area to jump to a characteristic length and the points where separation occurs are fixed. Bulk load applied at the free ends causes a smooth change in the size of contact and the development of the slip zones. The trends of energy dissipation with extent of contact and magnitude of tension and compression force, at various friction coefficients, have been found.