ANISOTROPIC DRY FRICTION BETWEEN 2 ORTHOTROPIC SURFACES UNDERGOING LARGE DISPLACEMENTS

This work deals with the formulation of anisotropic dry friction betwe en two orthotropic surfaces undergoing large displacements and small s trains. The structural tensors characterizing the contacting surface m aterial symmetries are introduced and used as parameters so that spati al friction constitutive functions can be objective while being anisot ropic. With the help of the theory of tenser function representations, the reduced forms of the friction law and slip rule are established. The existence of a slip surface is deduced from the rate-independence condition instead of postulating it beforehand. Under some regularity assumptions, a necessary and sufficient condition is given for the nor mality slip-rule to hold. Convex analysis is applied to investigating the fully anisotropic friction law derived from a convex dissipation p otential. The polarity operation is used to induce a one-to-one symmet ric correspondence between the dissipation and gauge slip functions.