Study of shear properties of rock structural plane by grouting reinforcement

In order to study the grouting reinforcement effect of structural plane in cracked rock mass of uniaxial compression test, and reveal the essence and mechanisms of grouting reinforcement, the roughness of structural plane in cracked rock mass was measured and studied. The influence of grouting on strength, joint roughness coefficient (JRC) and stiffness of structural plane was analyzed through the shear test of structural plane of rupture rock sample around grouting reinforcement; and the test result was back analyzed by using JRC-JCS mode. The mechanical properties and grouting effect were analyzed through the shear test of sawtooth structural plane modeling around grouting reinforcement. The results show that the JRC of structural plane in artificial cracked rock of the same rock mass is similar and replicable, and the value was about 8-10. Stiffness, peak shear strength, residual strength and slope of upward section of structural plane were significantly improved by grouting reinforcement. The theoretical formula of structural plane stiffness was given by theoretical analysis. The peak shear strength, residual strength and cohesion of structural plane increased markedly with the increase of sawteeth number on structural plane and after grouting reinforcement, but little change in the internal friction angle.