Research on failure mechanism and control measures of surrounding rock in large section raise shaft construction chamber

Aiming at the problem of serious deformation and failure of large section chamber surrounding rock, taking the large section reverse shaft construction chamber of Lijiahao Mine as the research background, using the research methods of numerical simulation, theoretical analysis and field monitoring, the deformation and failure law of surrounding rock of large section reverse shaft construction chamber of Lijiahao Mine is analyzed. The deformation and failure mechanism is revealed and the targeted control countermeasures are proposed. The results show that the roof rock of large section chamber is weak rock which is affected by excavation disturbance, the surrounding rock of roof is broken, and the horizontal and vertical displacement of roof are significant; the large section chamber has a large space, the roof rock is in the plastic zone, and the vertical displacement of the roof is 1 450 mm, 2.8 times that of the conventional section roadway; the key to the stability control of surrounding rock in large cross-section raise shaft construction chamber is roof support. The industrial application monitoring shows that the roof and floor deformation of the conventional section chamber has no obvious change, the maximum roof subsidence of the large section chamber is 132 mm, the maximum displacement of the two sides is 74 mm, and the floor has no obvious bulge, which effectively controls the deformation and damage of the surrounding rock.