ZHU Yong-jian, REN Heng, WANG Ping, et al. Grouting test and reinforcement mechanism analysis of rock with single penetrated fracture surface[J]. 2022, 43(12): 3221-3230.
ZHU Yong-jian, REN Heng, WANG Ping, et al. Grouting test and reinforcement mechanism analysis of rock with single penetrated fracture surface[J]. 2022, 43(12): 3221-3230.DOI: 10.16285/j.rsm.2022.0078.
For the problem that how the grouting reinforcement of a single penetrated structural plane affects the bearing capacity of surrounding rock
an approach of making rock samples with single penetrated fracture surface is proposed firstly
and the rock samples are injected with ultra-fine cement and epoxy resin
respectively. Then
the strength and deformation characteristics of the consolidated body under uniaxial (triaxial) compression are investigated with the RMT-150C experimental system. Finally
the micro consolidation mechanism of structural plane grouting is revealed by means of theoretical analysis and electron microscope scanning. It is found that the fracture surface generated under triaxial loading-unloading condition is closer to the engineering practice and meets the experimental requirements. The stress-strain characteristic curves of the specimens injected with superfine cement show phased deformation characteristics
and the curves of the specimens injected with epoxy resin are relatively smooth. For the strength characteristics
the influence of confining pressure is significantly larger than that of grouting material selection. Grouting reinforcement can improve the residual strength of rock mass. With the increase of confining pressure
the increase of improvement coefficient of residual strength is less obvious
and the peak strength of consolidated body is closer to that of intact rock. For the failure characteristics
the main fracture surface of the specimen injected with ultra-fine cement shears and slips along the original fracture surface
and the main fracture surface of the specimen injected with epoxy resin is a new penetrated fracture surface. Finally
based on the Mohr-Coulomb criterion
the relationship between the bonding force of grouting materials and the strength improvement coefficient of structural plane is established. It is found that the strength improvement coefficient of structural plane has a linear relationship with the bonding force of grout. The comparison between calculation and test results shows that the formula is reasonable and can provide reference for the optimization of deep surrounding rock support.