A Study of Crack Initiation Locations in Rock Mass Considering Linings of High-Pressurized Hydrogen Storage Cavern

Abstract

Hydrogen has become an essential component of the energy transition because of its ability to store excess energy from renewable sources and reduce carbon emissions. Among underground storage options, Lined Rock Caverns (LRCs) offer unique advantages for large-scale hydrogen storage. They can operate at high pressures, even at shallow depths, and offer flexibility independent of geological formations, making them a promising candidate for large-scale hydrogen storage. From the phenomenon where metallic materials or steel lose ductility, causing reduced tensile strength after exposure to hydrogen, leading to premature failure, this phenomenon is called hydrogen embrittlement. The hydrogen embrittlement phenomenon leads to a dispute about adopting the knowledge from past studies of high-pressure underground storage (for gas and compressed air) to store hydrogen. This study investigates critical challenges in utilizing LRCs for hydrogen storage, focusing on the effects of in-situ stress condition on the position of crack initiation in the rock mass under high internal pressure, together with lining system consideration. A numerical approach is used to evaluate how stress conditions influence the crack initiation position. The results indicate that, when considering the lining system in the analysis, the failure initiation locations in the rock mass significantly differ from those in previous studies (without linings). The failures would first appear in the concrete lining, indicating the necessity for future study for high-pressure hydrogen storage.