### A generalized strange term in Signorini’s type problems

The limit behavior of the solutions of Signorini’s type-like problems in periodically perforated domains with period $\epsilon $ is studied. The main feature of this limit behaviour is the existence of a critical size of the perforations that separates different emerging phenomena as $\epsilon \to 0$. In the critical case, it is shown that Signorini’s problem converges to a problem associated to a new operator which is the sum of a standard homogenized operator and an extra zero order term (“strange term”) coming from the...