The relationship between the deformation mechanism and permeability on brittle rock

In order to study the relationship between the deformation mechanism and permeability on brittle rock, the curves of stress–strain and permeability–strain of brittle rock were analyzed, the results indicated that the permeability of brittle rock increased rapidly at the critical failure point due to the microstructure changed seriously during the compaction, elastic deformation, and progressive failure process. When the rock bridges or asperities on the internal structural plane were ruptured partly or completely after the peak stress, a sudden decrease in rock strength occurred and the peak permeability could be the maximum. The strain at the critical point and turning point on the stress–strain curve corresponded to that at the rapid increase point and the peak point on the permeability–strain curve according to the renormalization theory and curves of stress–strain and permeability–strain. In addition, the ratios could be described by mathematical expressions. The conclusions could be proved reasonably by the experimental studies and examples of statistical analysis.