TY  - JOUR
ID  - epos2138
UR  - http://doi.org/10.1016/j.ijrmms.2018.07.023
A1  - Balland, Cyrille
A1  - Billiotte, Joël
A1  - Tessier, Bruno
A1  - Raingeard, Anne
A1  - Hertz, Emmanuel
A1  - Hévin, Grégoire
A1  - Tribout, Daniel
A1  - Thelier, Nicolas
A1  - Hadj-Hassen, Faouzi
A1  - Charnavel, Yvan
A1  - Bigarre, Pascal
Y1  - 2018///
N2  - Natural gas storage in salt caverns requires fast injection / withdrawal cycles due to the increasing dynamics of the energy market. High rates induce rapid changes in the internal pressure of the stored gas causing important temperature changes susceptible to damage the rock salt mass. To experimentally observe this, the Starfish project aimed to characterize the damage caused by purely thermal stresses at the surface of a large bloc of rock in the salt mine of Varangéville (France). The objective was to determine the type of failure mechanism involved with repeated cooling stages. Since the salt is favourable to the generation of Acoustic Emissions (AE) and the propagation of stress waves, acoustic monitoring was chosen as one of the methods to follow the impact of the salt cooling. In addition to thermal and mechanical sensors, an acoustic monitoring device consisting of 16 ultrasonic sensors was installed on the free surface and in boreholes. It enabled to record and locate a large number of AE (58,426) located with good accuracy (2.5?cm). Those AE can be correlated to the evolution of salt fracturing. Acoustic activity is very intense at the start of each cooling cycle, then decreases with time to reach a very low level (background) after about 15 days. The average localisation depth reached by the AE is about 90?cm during the first cooling period. For subsequent cooling cycles, this depth is limited to 74?cm. These results show that the first cooling period is decisive, as it contains the strongest and deepest acoustic emissions.
PB  - Elsevier Science
JF  - International Journal of Rock Mechanics and Mining Sciences
VL  - 111
KW  - Acoustic monitoring
KW  -  Underground salt mine
KW  -  Gas storage
KW  -  Energy
KW  -  Rock mechanics
KW  -  France
SN  - 1365-1609
TI  - Acoustic monitoring of a thermo-mechanical test simulating withdrawal in a gas storage salt cavern
SP  - 21
AV  - none
EP  - 32
ER  -