Experimental Study on Anisotropy Mechanical Properties of Corroded Rock Mass

Corroded rock mass usually plays a key role in controlling the stability of rock mass engineering. In order to reveal the evolution law of anisotropic mechanical properties and failure characteristics of the bedded rock mass suffering corrosions, indoor uniaxial compression tests were carried out on rock masses with different corrosion rates (K = 0%, 5%, 10%, 15%, 20%) to obtain their compressive strength and elastic modulus at different included angles (α = 0°, 30°, 45°, 60°, 90°) . Based on the test results, mathematic models for predicting the compressive strength and elastic modulus of the corroded rock mass with beddings were established and then validated by experiment. The results show that the compressive strength achieves its maximum value at the included angle α = 0°, 90°, and achieves its minimum value at α = 45°, presenting a symmetrical U shape as a whole; while the elastic modulus is the smallest at α = 60° and the largest at α = 90°, showing an asymmetric U shape as a whole. The anisotropy indexes of compressive strength and elastic modulus (i.e., RP and RE) of the intact rock mass are the largest, which are 1.98 and 3.05 respectively, and their values gradually decrease with the corrosion rate increasing. When K = 20%, RP and RE are 1.10 and 1.36, respectively. The deformation and failure of rock mass with small corrosion rates are controlled by rock matrix and beddings, mainly by splitting, staggered shear and sliding shear. As the corrosion rate increases, the deformation and failure are obviously controlled by dissolution pores and skeleton, and the skeleton swelling, shear dislocation and crushing failure are the main types.