Characterizing concrete lining damage in underground high-pressure hydrogen storage lined rock caverns with validated numerical models

Large-scale underground high-pressure hydrogen storage is critical for low-carbon energy transition, while lined rock caverns (LRCs) are the core infrastructure for high-pressure hydrogen and compressed air energy storage. Severe tensile damage of concrete lining under 10–20 MPa internal hydrogen pressure threatens structural integrity and sealing safety. This study establishes a 3D refined steel-concrete-rock numerical model based on the Swedish Skallen LRC project, well validated by field hydraulic test data with relative error < 5.5%. The Concrete Damaged Plasticity (CDP) model is adopted to characterize tension-dominated damage evolution and spatial distribution of concrete lining under high-pressure hydrogen loading. Parametric sensitivity analysis is conducted, and results indicate that rock mass quality and in-situ stress are dominant factors, whereas concrete strength and sealing layer material show limited influence. A damage-control design principle is proposed to support site selection and performance-based design of high-pressure hydrogen storage LRCs.