Abstract: In this paper, to find out the failure characteristics and fracture evolution law of anchored body in roadway surrounding rock, the deformation and failure progress of anchored bodies and working resistance varation of bolts under the combined loadings were simulated. The results show that the horizontal stratifications which are perpendicular to bolts will appear when the lateral pressure coefficient λ meets the condition of 1≤λ≤1.4. When λ satisfies 1.4＜λ≤1.6, fine fractures will appear in anchored rock mass, bolts plates are entrapped in stratum, rock bodies between bolts fall off in pieces, loosening damages appear in the rock mass on the bottom of anchored body, and the anchored body is stable, but the inclined fractures will appear outside of anchored body, which are 30°~40° relative to the strata planes. When λ is equal to 2.0, separations between bolted area and no-bolted area increase, block size and depth of strata on the bottom of anchored body are increased, the bolt plates are disabled, and the integral instability of anchored body appears. Meanwhile, there exists obvious positive correlation between λ and fractal dimension of anchored body, D. With the increase of λ, the working resistances have little differences between bolts, which show a wavy decreasing tendency, and the bearing capacity of anchored body in the wall of roadway changes little, while the bearing capacity in the roadway roof decreases gradually. Moreover, the horizontal loadings have more obvious influence on the stability ofanchored body in roadway roof, while the separations increase with the increase of λ, and inhomogeneous subsidence appears within anchored body.

Key words: anchored body, fracture, failure characteristics, bolt loading