Mixed Mode Fracture Investigation of Rock Specimens Containing Sharp V-Notches

Area of Science:

• Geotechnical Engineering
• Materials Science
• Solid Mechanics

Background:

• Rock fracture mechanics is crucial for engineering applications.
• Sharp V-notches (SV-notches) significantly influence rock failure.
• Mixed mode I/II loading conditions are prevalent in geological formations.

Purpose of the Study:

• To experimentally and analytically assess the fracture behavior of rock with SV-notches under mixed mode I/II loading.
• To validate the predictive capability of the MTS-FEM criterion for such scenarios.
• To investigate the influence of notch opening angles on fracture resistance.

Main Methods:

• Mixed mode fracture tests on Brazilian disk specimens with SV-notches (SVNBD samples).
• Application of the Maximum Tangential Stress-Finite Element Method (MTS-FEM) criterion for fracture prediction.
• Direct calculation of critical distance using finite element analyses on cracked samples.

Main Results:

• Experimental fracture tests were conducted on SVNBD samples with varying notch angles.
• The MTS-FEM criterion demonstrated good agreement with experimental fracture curves.
• The critical distance was effectively determined through finite element analysis.

Conclusions:

• The MTS-FEM criterion provides accurate predictions for the fracture behavior of V-notched rock under mixed mode loading.
• The proposed approach simplifies fracture analysis by avoiding stress series expansion coefficients.
• This research offers a reliable method for assessing the structural integrity of rock masses with V-shaped discontinuities.