Failure and Energy Evolution Characteristics of Saturated Natural Defective Material Under Different Confining...

Area of Science:

• Geotechnical Engineering
• Material Science
• Rock Mechanics

Background:

• Natural brittle materials often contain defects like microcracks, affecting their mechanical behavior.
• Water saturation can significantly attenuate the strength of defective materials, posing risks to engineering structures.
• Understanding energy evolution is crucial for characterizing the deformation and failure of brittle materials.

Purpose of the Study:

• To investigate the mechanical properties and energy evolution of water-saturated defective brittle materials under triaxial compression.
• To analyze the influence of confining pressure on strength, deformation, failure modes, and energy dissipation.
• To reveal the mesoscopic mechanisms of deformation and failure using the discrete element method.

Main Methods:

• Water saturation of natural defective brittle rock materials.
• Triaxial compression tests to determine mechanical properties and energy evolution patterns.
• Discrete element method (DEM) simulations to study macro- and micro-failure characteristics.

Main Results:

• Confining pressure significantly enhances peak compressive strength (up to 126.8%) and elastic modulus (up to 91.9%).
• Failure mode transitions from tensile splitting to shear failure with increasing confining pressure, altering fracture angles.
• Confining pressure increases total energy, elastic energy, and dissipated energy at peak load, with altered energy storage mechanisms.

Conclusions:

• Confining pressure plays a critical role in enhancing the strength and modifying the failure behavior of water-saturated defective brittle materials.
• Energy evolution patterns are significantly altered by confining pressure, impacting elastic energy storage and dissipation.
• Mesoscopic crack propagation shifts and fracture angles change with confining pressure, providing insights into material failure mechanisms.