Rigidité à la torsion d'un cylindre présentant une double périodicité

The objective of the present Note is to estimate the equivalent torsion rigidity modulus for a cylinder whose cross-section Σ exhibits a periodical distribution of porous zones Σ_P. Taking into account a second, finer, periodical distribution of pores in Σ_P, we have to use the homogenization method in a biperiodical context. However, the contrast of scales at the interfaces between Σ_P and the compact part Σ_C of Σ, requires some subtle fitting up of this method. Finally, we point out the existence of boundary layers around the interfaces ∂Σ_P and we estimate the weakening of the torque rigidness. To cite this article: M'B. Taghite et al., C. R. Mecanique 334 (2006).