Abstract: The design of steel plate thickness holds substantial significance in the context of the sealing layer design for compressed air energy storage (CAES) artificial caverns. To ascertain the relationship between the steel plate thickness and factors such as the cavern diameter, surrounding rock modulus, and internal gas storage pressure, a numerical simulation method was used to analyze the stress characteristics of the steel plate under the influence of these aforementioned factors. Furthermore, a theoretical analysis method was adopted to examine the critical buckling thickness of the steel plate under external water pressure and the corrosion thickness of the steel plate under the operating environmental conditions of the CAES artificial caverns. Ultimately, considering the influencing factors such as stress deformation, buckling characteristics, and corrosion rate of the sealing steel plate, a method for determining the thickness of the sealing steel plate was proposed. The research results show that the fitted empirical formula, which establishes the relationship between gas storage pressure and steel plate thickness, exhibits minimal error when calculating critical pressure or critical thickness. Specifically, the error calculated by stress control is a mere 2.37%, while that calculated by strain control is only 2.35%. The critical thickness of steel plate without stiffening ring presents a nonlinear increasing trend as external pressure rises, whereas the critical thickness of steel plate with stiffening ring exhibits a linear increasing trend with the augmentation of external pressure. In the environment characterized by high temperature and high humidity, the surface of steel plate undergoes overall uneven corrosion, with severe localized corrosion. Consequently, the thickness of steel lining should be increased accordingly. Finally, the method proposed in this paper for determining the critical thickness of the steel lining demonstrates favorable applicability under the research conditions delineated herein, thereby offering valuable insights for the design of steel plate sealing strategies.

Key words: compressed air energy storage, artificial caverns, steel liner, steel plate thickness