Microscopic and macroscopic instabilities in finitely strained porous elastomers

J. C. Michel (1) , O. Lopez-Pamies (2) , P. Ponte Castañeda (2) , N. Triantafillydis

1 Sons
2 LMS - Laboratoire de mécanique des solides

The present work is an in-depth study of the connections between microstructural instabilities and their macroscopic manifestations-as captured through the effective properties-in finitely strained porous elastomers. The powerful second-order homogenization (SOH) technique initially developed for random media, is used for the first time here to study the onset of failure in periodic porous elastomers and the results are compared to more accurate finite element method (FEM) calculations. The influence of different microgeometries (random and periodic), initial porosity, matrix constitutive law and macroscopic load orientation on the microscopic buckling (for periodic microgeometries) and macroscopic loss of ellipticity (for all microgeometries) is investigated in detail. In addition to the above-described stability-based onset-of-failure mechanisms, constraints on the principal solution are also addressed, thus giving a complete picture of the different possible failure mechanisms present in finitely strained porous elastomers.

Mots clés: Porous material; Elastic material; Finite strain; Stability and bifurcation; Finite elements

Domaines: Mécanique [physics.med-ph]; Mécanique des matériaux [physics.class-ph]; Mécanique des matériaux [physics.class-ph]

J. C. Michel, O. Lopez-Pamies, P. Ponte Castañeda, N. Triantafillydis. Microscopic and macroscopic instabilities in finitely strained porous elastomers. Journal of the Mechanics and Physics of Solids, 2006, 55 (5), pp.900-938. ⟨10.1016/j.jmps.2006.11.006⟩. ⟨hal-00111501⟩