Stability and airtightness of a deep anhydrite cavern group used as an underground storage space: A case study

This paper studies the usability of a deep mined-out anhydrite mine located in Anhui, China. The physical and mechanical parameters of the anhydrite intact rock and rock mass were determined through laboratory analysis and field investigation, and the stability of the cavern group was analyzed using the element safety factor method (ESFM) proposed in this paper. Moreover, the permeabilities of the anhydrite intact rock and rock mass were estimated based on laboratory and field tests. The results demonstrated that the stability and airtightness of the anhydrite cavern group are suitable for underground storage.