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A numerical solution for quasistatic viscoelastic frictional contact problems / Fatin F. Mahmoud in Transactions of the ASME . Journal of tribology, Vol. 130 N°1 (Janvier 2008) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 130 N°1 (Janvier 2008) . - 13 p. Titre : A numerical solution for quasistatic viscoelastic frictional contact problems Type de document : texte imprimé Auteurs : Fatin F. Mahmoud, Auteur ; Ahmed G. El-Shafei, Auteur ; Amal E. Al-Shorbagy, Auteur Année de publication : 2008 Article en page(s) : 13 p. Note générale : Tribology Langues : Anglais (eng) Mots-clés : Force  Creep  Friction  Viscoelastic  materials  Relaxation  (Physics)  Stress  Displacement  Equations  Stiffness  Equilibrium  (Physics) Résumé : The tribological aspects of contact are greatly affected by the friction throughout the contact interface. Generally, contact of deformable bodies is a nonlinear problem. Introduction of the friction with its irreversible character makes the contact problem more difficult. Furthermore, when one or more of the contacting bodies is made of a viscoelastic material, the problem becomes more complicated. A nonlinear time-dependent contact problem is addressed. The objective of the present work is to develop a computational procedure capable of handling quasistatic viscoelastic frictional contact problems. The contact problem as a convex programming model is solved by using an adaptive incremental procedure. The contact constraints are incorporated into the model by using the Lagrange multiplier method. In addition, a local-nonlinear nonclassical friction model is adopted to model the friction at the contact interface. This eliminates the difficulties that arise with the application of the classical Coulomb’s law. On the other hand, the Wiechert model, as an effective model capable of describing both creep and relaxation phenomena, is adopted to simulate the linear behavior of viscoelastic materials. The resulting constitutive integral equations are linearized; therefore, complications that arise during the integration of these equations, especially with contact problems, are avoided. Two examples are presented to demonstrate the applicability of the proposed method. En ligne : http://tribology.asmedigitalcollection.asme.org/article.aspx?articleid=1467977 [article] A numerical solution for quasistatic viscoelastic frictional contact problems [texte imprimé] / Fatin F. Mahmoud, Auteur ; Ahmed G. El-Shafei, Auteur ; Amal E. Al-Shorbagy, Auteur . - 2008 . - 13 p. Tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 130 N°1 (Janvier 2008) . - 13 p. Mots-clés : Force  Creep  Friction  Viscoelastic  materials  Relaxation  (Physics)  Stress  Displacement  Equations  Stiffness  Equilibrium  (Physics) Résumé : The tribological aspects of contact are greatly affected by the friction throughout the contact interface. Generally, contact of deformable bodies is a nonlinear problem. Introduction of the friction with its irreversible character makes the contact problem more difficult. Furthermore, when one or more of the contacting bodies is made of a viscoelastic material, the problem becomes more complicated. A nonlinear time-dependent contact problem is addressed. The objective of the present work is to develop a computational procedure capable of handling quasistatic viscoelastic frictional contact problems. The contact problem as a convex programming model is solved by using an adaptive incremental procedure. The contact constraints are incorporated into the model by using the Lagrange multiplier method. In addition, a local-nonlinear nonclassical friction model is adopted to model the friction at the contact interface. This eliminates the difficulties that arise with the application of the classical Coulomb’s law. On the other hand, the Wiechert model, as an effective model capable of describing both creep and relaxation phenomena, is adopted to simulate the linear behavior of viscoelastic materials. The resulting constitutive integral equations are linearized; therefore, complications that arise during the integration of these equations, especially with contact problems, are avoided. Two examples are presented to demonstrate the applicability of the proposed method. En ligne : http://tribology.asmedigitalcollection.asme.org/article.aspx?articleid=1467977