Mechanical response and failure mechanism of inclined rough jointed rock under true triaxial compression loading

• Increasing joint roughness enhances axial strength and peak strain in true triaxial compression. • Axial strength shows a non-monotonic trend with inclination angle: decreases from 30° to 60° then increases to 90°. • Failure mode depends on joint strike relative to principal stresses: parallel to intermediate stress leads to matrix or mixed shear failure, while parallel to minimum stress leads to matrix shear failure. • Acoustic emission analysis reveals that crack number and shear crack percentage increase with roughness and vary non-monotonically with inclination angle.