Poroelastic properties play an essential role in interaction between
deformation and fluid pressure change in porous materials. These
properties are inherently related to microstructural evolutions such as
porosity change and micro-cracks growth. In this study, the evolutions
of poroelastic properties of a hard rock (granite) are investigated in
terms of thermal micro-cracking process. Granite samples are first
subjected to a heating-cooling treatment with different values of
temperature. The evolutions of poroelastic properties (bulk modulus of
porous skeleton, compressibility modulus of solid matrix, Biot’s
coefficient) of treated samples are analyzed in terms of micro-cracks
induced by the heating-cooling treatment. It is found that both
connected and occluded micro-cracks are generated in granite samples.
The bulk modulus of porous skeleton is affected by the connected
micro-cracks while the compressibility modulus of solid matrix is
influenced by the occluded micro-cracks. Biot’s coefficient is affected
by the connectivity of micro-cracks.