Effective thermal conduction of a Signorini-type problem in composites with rough interface

We analyse the effect of a Signorini-type interface condition on the asymptotic behaviour, as {\epsilon} tends to zero, of a problem posed in an open bounded cylinder of {R^N}, {N\geq 2}, divided in two connected components by an imperfect rough surface. The Signorini-type condition is expressed by means of two complementary equalities involving the jump of the solution on the interface and its conormal derivative via a parameter {\gamma}. Different limit problems are obtained according to the values of {\gamma} and the amplitude of the interface oscillations.