Experimental and numerical studies on rock damage law in straight-hole cut blasting under biaxial confining pressure

• Crack propagation in straight-hole cut blasting is negatively correlated with confining pressure; higher confining pressure reduces crack width, length, and development time. • Blasting reduces rock compressive strength, with attenuation decreasing as distance from the blast source increases; higher confining pressure inhibits strength attenuation. • Numerical simulations show that under the same confining pressure, stress peaks first at the blast hole bottom; higher confining pressure prolongs stress peak duration and reduces cavity volume and crack propagation. • Under 4 MPa confining pressure, the longest crack was only 154.5 mm in length and 102 mm in depth, providing a basis for optimizing deep rock roadway blasting design.