Rheological Behaviour of Rock Salt Under Uniaxial Compression

Rock salt is considered as the most suitable material for underground storage of hydrocarbons as well as the disposal sites for hazardous waste in view of its unique physical and mechanical behaviour. In India, rock salt reserves are spread sub-surface over an area of more than 50,000 sq.km. covering much of north-western region of Rajasthan. So far, limited studies on the physical and mechanical properties of rock salt in this region have been carried out. This paper discusses the behaviour of rock salt under uniaxial compression (UCS) measured from the samples collected in-situ. As reported in literature that the rock salt is likely to exhibit highly viscous behaviour, and therefore there is a need for understanding rheological behaviour of rock salt through a theoretical model. In the present study, a rheological model is proposed for predicting the stress-strain behaviour of Indian rock salt under UCS condition. Predicted stress-strain curve from the proposed rheological model using MATLAB is compared with the experimentally measured stress-strain curve. Comparison of the both experimental and predicted results indicates that proposed rheological model is able to predict stress-strain behaviour of rock salt under UCS condition. The results show that rock salt exhibits distinct time-dependent viscous behaviour and deformations.