A seepage calculation method in geomaterials based on the novel improved DEM-FDM

Area of Science:

• Geotechnical Engineering
• Computational Mechanics
• Fluid Dynamics

Background:

• Seepage significantly influences the mechanical behavior and damage patterns in geotechnical materials.
• Understanding the complex interactions between seepage and soil mechanics is critical for infrastructure stability.
• Existing numerical methods may face challenges in accurately and efficiently simulating coupled seepage-geotechnical processes.

Purpose of the Study:

• To develop and validate a novel hydraulic coupling numerical simulation algorithm for geotechnical seepage.
• To investigate the intrinsic mechanisms governing the interaction between geotechnical materials and seepage.
• To enhance the simulation of soil damage phenomena, such as gushing soil, under hydraulic conditions.

Main Methods:

• A hybrid numerical algorithm combining interpolation finite difference method (FDM) and discrete element method (DEM).
• Construction of an irregular fluid calculation grid around individual particles for detailed analysis.
• Derivation of the two-dimensional unsteady seepage governing equation and its stability conditions using interpolation and FDM.
• Numerical investigation of seepage calculation efficiency by varying difference format parameters.

Main Results:

• The improved FDM effectively simulates two-dimensional soil seepage with high computational efficiency.
• Seepage calculation efficiency is positively correlated with hydraulic conductivity and time step, and negatively with spatial step.
• The proposed method accurately captures the generation and progression of gushing soil damage under hydraulic drive.
• The algorithm demonstrates robust performance in simulating complex geotechnical seepage scenarios.

Conclusions:

• The developed FDM-DEM algorithm provides an efficient and accurate tool for simulating geotechnical seepage and associated damage.
• The findings offer a strong theoretical foundation for studying geotechnical seepage fields and their failure mechanisms.
• This research contributes to improved predictive capabilities for geotechnical engineering projects involving fluid flow and soil instability.