Abstract:
In view of the problem of large deformation amount of the surrounding rock in the stoping roadway of a large mining height working face in a mine, by theoretical analysis and numerical simulation, it is confirmed that the original support scheme has sufficient support strength, but the support range is insufficient, resulting in a relatively large deformation amount of the roadway surrounding rock and relatively large range of plastic zones. On the basis of the original support scheme, the support range is expanded, and three schemes are designed for comparation and analysis. Comprehensively considering the support effect and cost, the optimized support parameters are determined as follows: the roof anchor rod uses a diameter of 22 mm×3500 mm threaded steel anchor rod, with a spacing and row spacing of 1000 mm; the roof anchor cable uses a diameter of 21.8 mm×8300 mm steel stranded wire, with a spacing and row spacing of 2000 mm; the roadway side uses a diameter of 22 mm×2200 mm threaded steel anchor rod, with a spacing and row spacing of 1000 mm, and on-site testings are conducted on the 85218 working face. The on-site monitoring data show that compared with the original support scheme, the optimized support scheme can effectively control the deformation of the roadway surrounding rock, with a significant reduction of about 29.4% in deformation amount, and the stress status of the anchor rod (cable) is good, with no failure risk.