Abstract:Real-time computerized tomography(CT) experimental results of sandstone failure process under triaxial compression with chemical corrosion and permeation of chemical solution are presented. The changes of CT numbers of every scanning layer are analyzed under triaxial compression with and without permeation at different CT scanning stages;and the stress and time that deformation lasts in different testing stages are studied for sandstone samples with and without corrosion under triaxial compression with and without permeation. The effect of permeation on sandstone strength is obtained. The test results of CT images and CT numbers show that crack-tip closure is resulted from the development of microcrack under the environment without permeation during the process of microcrack propagation to principal crack coalescence,after which cracking continues under the environment with permeation due to pore water pressure. Because of permeation and pore water pressure,more cracks are generated in the specimens under the environment with permeation but they are relatively single in the specimens under the environment without permeation. From initial linear elastic deformation to crack-tip fracture,the effect of permeation on the stress and time that deformation lasts is main key factor and the chemical corrosion is a secondary factor. From crack-tip fracture to crack coalescence,the stress and time that deformation lasts are decided by both permeation and chemical corrosion. The effect of permeation on sandstone strength is obvious. The strength is much greater under the environment without permeation than that with permeation. For example,the strength under the environment with permeation occupies 16.6% of that without permeation for the specimens corroded by NaCl solution with concentration of 0.01mol/L and pH value of 2.