Incremental variational approach for time dependent deformation in clayey rock

Yanqiu Huang (1) , Ariane Abou-Chakra Guéry (2) , Jian-Fu Shao (1)

1 LML - Laboratoire de Mécanique de Lille - FRE 3723
2 LMDC - Laboratoire Matériaux et Durabilité des constructions

An extension of Lahellec (2007) incremental variational approach to geomaterials is proposed. By using an implicit time-discretization scheme, the evolution equations describing the small strains constitutive behavior of the phases can be reduced to the minimization of an incremental energy function. This minimization problem is rigorously equivalent to a nonlinear thermoelastic problem with a transformation strain that is a heterogeneous field. The new approach proposed is for Callovo-Oxfordian argillites and considers the specific properties of geomaterials such as compressibility-dilatancy transition and influence of confining pressure. An isotropic, kinematic hardening effect is also considered for the more general cases. The accuracy of the model is assessed by comparison with FE and experimental results.

Mots clés: Homogenization; Clayey rock; Incremental variational approach; Nonlinear; Visco-plastic

Yanqiu Huang, Ariane Abou-Chakra Guéry, Jian-Fu Shao. Incremental variational approach for time dependent deformation in clayey rock. International Journal of Plasticity, 2014, 64, pp.88-103. ⟨10.1016/j.ijplas.2014.07.003⟩. ⟨hal-01064014⟩