In situ measurements of the mechanical response of rock-salt on variable pressure load
The variable pressure device (VPD) has been used to measure the instantaneous and time-dependent response of rock-salt on pressure changes in the borehole. The aim of the measurements is to derive constitutive parameters to describe the thermo-mechanical behaviour of rock-salt. The description of the constitutive behaviour frequently used assumes that the total deformation is the sum of a linear elastic part and a secondary creep part. Effects of primary creep and time independent effects caused by micro cracks and plasticity are taken into account by reducing the modulus of elasticity. The best estimate of the modulus of elasticity derived from the measured instantaneous response is 22.4 GPa. This value does not differ much from the Young's Modulus which implies that the time independent features have little effect on the behaviour of the salt around the borehole. Further consequences for the description of the constitutive behaviour have to be investigated. Due to measuring inaccuracies, the time dependent response could not be used to derive constitutive parameters.
Bibliographic Reference: EUR 14440 EN (1993) 84 pp., FS, ECU 11.50
ISBN: ISBN 92-826-5821-X
Record Number: 199310803 / Last updated on: 1994-11-29
Original language: en
Available languages: en