Assessment of Coulomb Friction in Modeling Joint Mechanics via a Parameter Study of Dissipation

Abstract

Coulomb friction has been found to be very useful in many problems involving macroslip, and it is indeed a standard tool in critical calculations involving damping of moving components in jet engines. On the other hand, there is very little published evidence of problems involving partial slip where micro-modeling using Coulomb friction has been demonstrated to reproduce experimental results. Presented here is a systematic study comparing experimental data with fine-mesh finite element predictions for a category of “simple lap joints.” A thorough parametric study is used to explore the limitations of Coulomb friction in simultaneously capturing the behavior of partial-slip interfaces under a variety of loading conditions. From the results of the study, it is evident that though there is some value to finite element modeling of joints in partial slip using Coulomb friction, there are substantial limitations to those predictions. In particular, the Coulomb friction model is unable to capture the power-law relationship between dissipation and applied force, and the calibrated models are able only to span macroslip regimes or microslip regimes, but not both.