Research status of creep–fatigue characteristics of salt rocks and stability of compressed air storage in salt caverns

Energy is an important resource that supports the development of human society, and energy security is even more relevant to the strength of a country. In order to ensure energy security, countries around the world are taking measures to carry out energy transformation and construct new energy systems. As an important part of the new energy system, energy storage technology is highly valued by all countries. Among many large-scale energy storage technologies, salt cavern compressed air energy storage (CAES) technology stands out for its safety and economy, which is recognized and valued by scholars from various countries. For the construction of salt cavern CAES power station, it is very important to ensure the stability of salt cavern. Therefore, scholars have investigated the mechanical properties of salt rocks and the stability of salt caverns for CAES. This paper synthesizes the findings of current research on the creep and fatigue properties of salt rock, highlighting three key points: The factors influencing the creep and fatigue characteristics of salt rock include its composition, stress levels, and temperature. Notably, impurities and surrounding pressure tend to inhibit the deformation of salt rock, whereas elevated temperature and differential stress facilitate its deformation; The mechanisms governing creep and fatigue damage in salt rock are primarily associated with dislocation movement and microcracking; Most existing constitutive models for creep and fatigue are based on viscoelastic-plasticity theory, with fewer models derived from micro-mechanical perspectives. Additionally, this paper reviews studies on the stability of salt cavern CAES reservoirs utilizing numerical simulation methods and offers insights into future research directions concerning the creep and fatigue properties of salt rocks.