Multiphase time dependent compression behaviour of two chalks

In this paper, the multiphase time dependent compression behaviour of two chalks are considered within a fully coupled general hydro-mechanical framework derived from the mechanics of unsaturated soil. In the former case, reservoir chalks contain oil and water and subsidence appeared once enhanced oil recovery by waterflooding started. In the latter case, water saturated chalk is periodically desaturated by water evaporation, resulting in air penetration. In this paper, the fluid retention curves of both samples are determined and the data obtained are used in the interpretation of suction controlled compression tests where time effects appear to be significant. The experimental data obtained show the relevance of the approach adopted.