ON THE STABILITY AND POSTCRITICAL BEHAVIOR OF ELASTIC STRUCTURES WITH DRY FRICTION

The stability of discrete elastic systems subjected to conservative loading is governed by the potential energy, which is a function of the generalized coordinates. When dry friction is present, it affects the stability conditions and the post-critical response. Quasi-static loading is considered and the normal forces to the friction surface are assumed to be specified. General critical state conditions are obtained in terms of the potential energy and the dissipation function. Then several examples are presented to illustrate various types of behavior. It is seen that limit points, bifurcation points, and transition points (associated with slip activation or deactivation) may occur on the deformation path, and that a sudden "snap" from one state to another is a common phenomenon when the system includes dry friction.