• Bolted en-echelon joints exhibit faster shear strength deterioration and higher cumulative strength loss (20.04%–72.76%) compared to unbolted joints.
• Anchorage effectiveness is orientation-dependent, with optimal performance at 0° and –60° joint angles.
• Bolts accelerate the transition from rolling to sliding friction, enhancing energy absorption under cyclic shear.
• Rock bolts expedite crack initiation and energy release, as evidenced by accelerated AE hit and energy curve transitions.