• ACRs are a novel type of repeated rockbursts in deep tunnels under drilling and blasting within locked-in stress zones, potentially lasting 7–10 days and affecting areas over 20 m along the tunnel axis.
• Locked-in stress zones arise from interactions among multiple structural planes in tectonically active regions; blasting disturbances trigger early slippage and fracturing, with MS events migrating ahead of the working face.
• High-energy MS events dominate during ACR development and occurrence, extending 20–30 m (3–4 tunnel diameters) ahead of the working face, while tensile fracturing is the predominant failure mode.
• Monitoring MS event locations ahead of the working face offers a reliable prewarning strategy for identifying potential ACR-prone zones and enhancing tunnel construction safety.