The anchoring effect of granular mixture is studied using the mesoscopic numerical simulation method. Three-dimensional polyhedral particles and their distributions are built based on stochastic simulation technology. With the stochastic granule discontinuous deformation model and the simulation of anchors

the numerical implementation of the bolted gravel experiment is realized. The macroscopic and mesoscopic mechanical performances of anchored granular material are analyzed. The impact of the anchor density and its relationship with the particle size on the mechanical properties of granular mixture is studied; and the anchorage mechanism of granular mixture is discussed. Samples with different anchor spacings and different particle sizes are generated. The simulated results show that the numerical anchored granular mixture experiment can well reflect the deformation and anchoring effect of the different anchored granular structures; and their macroscopic properties have some relationship with the evolution of mesoscopic fabric. The anchorage mechanism is that the compression zone is formed in granular mixture

and the contact forces between granular materials are reinforced by the squeeze effect. Granular structural integrity has been strengthened and the structure is able to withstand a certain load. Without considering the anchor length

when the anchor spacing is less than three times the average particle size of granular mixture

the anchors can effectively reinforce granular mixture and a stable structure can be formed.