Stability evaluation and failure analysis of rock salt gas storage caverns based on deformation reinforcement theory

To perform a stability evaluation of underground gas storage caverns, the strength reduction finite element method is introduced into deformation reinforcement theory (DRT). The stability criterion of gas storage in caverns is established based on the K ∼ ΔE curve, where K is the strength reduction factor (SRF) and ΔE is plastic complementary energy (PCE). With respect to the state of instability, PCE quantitatively indicates the global stability of gas storage caverns, whereas the unbalanced force (UF) clearly specifies the local failure position and failure mode of gas storage caverns. A comparison between the results of geo-mechanical model testing and numerical simulation verifies the correlation between the UF and failure. DRT is applied to the stability evaluation and failure analysis of a gas storage double cavern, as well as the projected performance of rock salt gas storage caverns.