In‐Depth Analysis of the Effects of Temperature–Pressure and Degree of Hydration on the Mechanical Properties of Montmorillonite: Insights From Molecular Dynamics Simulations

ABSTRACT Shale oil and gas, as an essential type of unconventional oil and gas resources, and compressibility is one of the most critical aspects of shale oil and gas exploration and development. Elastic parameters have a significant impact on the compressibility of shale. Montmorillonite is one of the typical clay minerals in shale, and its microstructure has unique characteristics. When encountering water underground, it is effortless to expand. Therefore, the study of the mechanical properties of montmorillonite is crucial. This study is based on molecular dynamics simulation to establish Na‐montmorillonite with different hydration degrees, change its temperature and pressure, conduct comprehensive research and comparison by combining the elasticity parameter of montmorillonite with different hydration degrees, and explain the micro mechanism of its impact. Simulation results display that the mechanical properties of hydrated montmorillonite are negatively correlated with temperature. There is a positive correlation with pressure. As the degree of hydration increases, the mechanical properties of montmorillonite decrease. The mechanical properties of montmorillonite are anisotropic. The factors that play a leading role in the stage of temperature, pressure and hydration degree under micro and macro conditions are studied. This research achievement has guiding significance for the comprehensive understanding of montmorillonite and the elastic parameters of shale at the micro level.