Coupling in poroelasticity and thermoelasticity

A brief derivation is given of the equations of linearised poroelasticity and thermoelasticity. Dimensionless parameters are presented that quantify the strength of the coupling between mechanical and hydraulic (or thermal) effects. The poroelastic coupling parameter is shown to be the product of the Blot coefficient and the Skempton coefficient; the thermoelastic coupling parameter can be interpreted as the ratio of stored elastic strain energy to stored thermal energy. For liquid-saturated rocks, the poroelastic coupling parameter usually lies between 0.1 and 1.0, which means that the mechanical deformation has a strong influence on the pore pressure. The thermoelastic coupling parameter is usually very small, so that, although the temperature field influences the stresses and strains, the stresses and strains do not appreciably influence the temperature field. (C) 2000 Elsevier Science Ltd. All rights reserved.