A universal hydro-mechanical coupled behavior model for clay-bearing strata-Molecular-level simulation approach

Area of Science:

• Geotechnical Engineering
• Environmental Science
• Materials Science

Background:

• Clay minerals exhibit significant volume changes with water, complicating strata behavior under stress.
• Accurate prediction of hydro-mechanical responses in clay-bearing strata is crucial for engineering and environmental applications.

Purpose of the Study:

• To formulate a comprehensive hydro-mechanical behavior model for clay-bearing strata.
• To overcome limitations of existing models by incorporating detailed structural and fabric information.

Main Methods:

• Utilized Molecular Mechanics and Molecular Dynamics simulations on natural clay-bearing strata structures.
• Employed Monte Carlo techniques for structure formulation and molecular-level parameter acquisition.
• Developed a mathematical model based on simulation results to predict hydro-mechanical behavior.

Main Results:

• The model predicts hydro-mechanical behavior across diverse conditions, including various mineral compositions, salt content, pressures, and strains.
• Validated through laboratory and field tests, covering elastic and elasto-plastic regions.
• Successfully validated against existing data for swelling clays like MX-80 and FEBEX Bentonite.

Conclusions:

• The developed model demonstrates a universal applicability for predicting the hydro-mechanical behavior of clay-bearing strata.
• Enhances the reliability of engineering and geoenvironmental assessments involving clays.