Variational principles and estimates for the rigidities of bodies with voids

Variational principles and estimates (including two-sided estimates) are obtained for the rigidities of bodies containing periodic systems of pores (voids). The problem is examined on the basis of the asymptotic averaging method. Siberian State Academy of Telecommunications and Informatics, Novosibirsk 630009. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 4, pp. 148–154, July–August, 1998.