NUMERICAL STUDY OF THE CHEMO-PORO-MECHANICAL BEHAVIOUR OF THE CEMENT SHEATH DURING CO 2 INJECTION

Valerie Vallin (1) , Jean-Michel Pereira (1) , Antonin Fabbri (2) , Henry Wong (3) , Nicolas Jacquemet (2)

1 UPE - Université Paris-Est
2 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
3 ENTPE - École Nationale des Travaux Publics de l'État

This paper aims at describing the influence of carbonation on the poromechanical behaviour of a wellbore cement. Attention is paid to the estimation of the damage risk of the cement sheath in the context of CO 2 geological storage. A chemoporomechanical model is presented. It accounts for the main chemical reactions occurring within the cement matrix and their consequences in terms of matrix dissolution and carbonates precipitation. These porosity changes are accounted for by introducing a chemical porosity associated to the cement matrix dissolution and the porous volume occupied by carbonate precipitates. The model has been implemented in a finite volume code. An axisymmetrical configuration is considered. Evolutions of transport characteristics and mechanical behaviour during carbonation process are predicted. The damage risk of the cement sheath is finally estimated through the calculation of the elastic energy stored within the solid matrix.

Mots clés: CO 2; Geological storage; Cement carbonation; Chemo-poromechanics

Domaines: Sciences de la Terre

Valerie Vallin, Jean-Michel Pereira, Antonin Fabbri, Henry Wong, Nicolas Jacquemet. NUMERICAL STUDY OF THE CHEMO-PORO-MECHANICAL BEHAVIOUR OF THE CEMENT SHEATH DURING CO 2 INJECTION. IV International Conference on Computational Methods for Coupled Problems in Science and Engineering COUPLED PROBLEMS 2011, Jun 2011, Kos, Greece. ⟨hal-03707881⟩