Bearing Characteristics and Support Sensitivity of Reclaimed Rock Mass

After being disturbed, the regenerated rock mass is prone to looseness and fragmentation, but under the support effect, the regenerated rock mass still has a certain bearing capacity, especially with significant improvement in post peak bearing capacity, which is the foundation for controlling the stability of the regenerated rock mass roadway. To study the bearing characteristics of recycled rock mass and the influence of support on the bearing capacity of recycled rock mass, a four-factor mixed level orthogonal test was designed for uniaxial loading of recycled rock mass. The bearing mechanism of recycled rock mass is analyzed. The significance of anchor spacing, rod diameter, anchor length, and metal mesh on the post peak weakening trend and bearing capacity of recycled rock mass is tested based on orthogonal analysis of variance. The results show that: Under the conditions of no support and partial anchor support, the regenerated rock mass undergoes compression shear failure under uniaxial loading, while some anchor support regenerated rock mass undergoes splitting failure, and the metal mesh constrained regenerated rock mass specimen undergoes plastic sliding failure. The residual strength of the regenerated rock mass after fracture exhibits fluctuating characteristics. The stability of the post peak bearing stage depends on the friction effect of multiple fracture surfaces, and the support reinforcement friction effect resists the sliding and dislocation of the broken block under external loads. The metal mesh has a significant impact on the post peak bearing capacity of the recycled rock mass, while the change in anchor rod parameters only affects the weakening trend of the strength of the recycled rock mass.