Experimental investigation on the time dependent behaviour of a multiphase chalk

A series of high pressure oedometer compression tests were carried out on samples of Lixhe chalk (Belgium) containing various pore fluids: water, air (dry sample), oil (Soltrol) and oil/water under a controlled suction of 200 kPa. Strain curves with respect to time of tests carried out under a constant load were examined in a purpose of investigating the time dependent behaviour of chalk. A simple empirical exponential law able to account for the combined effects of stress and suction is proposed. Experiments show that it provides satisfactory results to predict a feature of multiphase chalk behaviour that is important in the study of the behaviour of oilfields