Normal and tangential stiffnesses of rough surfaces in contact via an imperfect interface model.pdfVIP

International Journal of Solids and Structures 87 (2016) 245–253 Contents lists available at ScienceDirect International Journal of Solids and Structures journal homepage: /locate/ijsolstr Normal and tangential stiffnesses of rough surfaces in contact via an imperfect interface model Maria Letizia Raffa a,b,?, Frédéric Lebon a, Giuseppe Vairo b a LMA, Aix-Marseille University, CNRS, Centrale Marseille, 4 Impasse Nikola Tesla CS 40006, 13453 Marseille Cedex 13, France b Department of Civil Engineering and Computer Science Engineering (DICII), University of Rome “Tor Vergata”, via del Politecnico 1, 00133 Rome, Italy article info Article history: Received 4 August 2015 Revised 7 January 2016 Available online 26 February 2016 Keywords: Interface contact stiffness Contact area Imperfect interface approach Homogenization of a microcracked interphase Asymptotic analysis abstract In this paper a spring-like micromechanical contact model is proposed, aiming to describe the mechanical behavior of two rough surfaces in no-sliding contact under a closure pressure. The contact region between two elastic bodies is described as a thin damaged interphase characterized by the occurrence of non-interacting penny-shaped cracks (internal cracks). By combining a homogenization approach and an asymptotic technique, tangential and normal equivalent contact stiffnesses are consistently derived. An analytical description of evolving contact and no-contact areas with respect to the closure pressure is also provided, resulting consistent with theoretical Hertz-based asymptotic predictions and in good agreement with available numerical estimates. Proposed model has been successfully validated through comparisons with some theoretical and experimental results available in literature, as well as with other well-established modeling approaches. Finally, the in?uence of main model parameters is addressed, proving also the model capability to catch the experimentally-observed dependence of the tan