A New In Situ Test for the Assessment of the Rock-Burst Alarm Threshold During Tunnelling

Abstract Rock-burst is one of the most serious risks associated with hard rock tunnelling and mining at high depths. Monitoring acoustic emissions emitted by rock-mass during excavation their interpretation now permits early assessment failure events makes safe management construction works possible. A reliable set-up alarm threshold thus fundamental for correct implementation procedures planned to minimise rock-burst related risk. This paper focuses on a novel in situ test specifically developed provide an experimental basis more accurate tunnelling, representative local geomechanical conditions. The test, thanks compression induced two flat jacks tunnel side wall, produces artificial process which are measured correlated mechanical response rock-mass, without typical limitations scale that characterised laboratory experiments. new methodology, named Mules method, was successfully tested some stretches Brenner Base Tunnel Brixner granite, affected mild spalling episodes. case-history fully described illustrate practical application proposed approach.