Study on the regulation of mine pressure and prevention technology in the gathering stage of the heading area of the narrow coal pillar along the open-pit tunnel

For the working face with rock burst danger along the open-pit tunnel, due to the complexity of its stress environment, the difficulty of rock burst prevention in the tunneling stage is greatly increased. Based on how to avoid the frequent occurrence of rock burst in the head area of the tunneling working face and ensure the safe and scientific connection of the working face, the theoretical analysis and practical exploration are carried out with the 31120 along open-pit tunneling working face of Nalinhe No.2 Mine as the engineering background. Through theoretical analysis, the occurrence mechanism of rock burst in the heading area of the tunneling working face is preliminarily discussed. Furthermore, the method of acoustic emission is adopted to analyze the range of acoustic events suddenly increased in the head lag area during the tunneling connection, and then the range is determined as the influence area of the tunneling connection. In order to eliminate the risk of rock burst, the pressure relief measures of multi-round cyclic large diameter drilling during the tunneling connection are designed, and the conclusion of good pressure relief effect is obtained through the analysis of the field measured data. This paper has important significance for improving the safety and stability of the 31120 along open-pit tunneling working face of Nalinhe No.2 Mine, and also provides useful reference for similar projects.