Stability Control and Support Optimization for a Soft-Rock Roadway in Dipping Layered Strata

Asymmetry and support issues can cause deformation and failure of the rock surrounding a soft-rock roadway in dipping layered strata. This paper evaluates the No. 1301 head gate in a mine as a case study to assess the instability mechanism related to the deformation and failure of the surrounding rock in this site and proposes stability control measures and a support scheme for the surrounding rock. The orthogonal test method is used to optimize the support parameters, and the supporting effect is evaluated based on numerical simulations and a field investigation. The results show that the instability of the surrounding rock is mainly influenced by the weak layer. The support scheme should use a combined support scheme with full anchor cable (long and short anchor cable)+wire mesh+steel belt as the primary support and a ladder beam as auxiliary support to strengthen critical areas. The overall deformation of the surrounding rock tends to be symmetrical, and the broken area of the surrounding rock is dramatically reduced; consequently, a large stable load-bearing structure is formed, ensuring the long-term stability of the roadway.