Structural damping caused by micro-slip along frictional interfaces

Damping in built-up structures is often caused by energy dissipation due to micro-slip along frictional interfaces (e.g., at bolted joints), which provides a beneficial damping mechanism and plays an important role in the vibration behavior of such structures. A careful study of the micro-slip phenomenon has been carried out using the finite element method. Two classical joint configurations, the press-fit joint and the lap-shear joint, have been used as the model problems. The focus of this paper is to evaluate the effect of dry friction on the damping response of frictional joint interfaces, to understand the evolution of the slip and stick regions along a joint interface during loading, and to quantify the amount of energy dissipation during cyclic loading and its dependence on structural and loading parameters. Finite element predictions are found to compare well with experimental measurements and are used to examine the validity and limitations of early analytical treatments in the literature.