Experimental study on change mechanism of coal and rock permeability under total stress and strain condition

Abstract

In order to study the permeability evolution law of coal and rock under the action of mining dynamic load, the Darcy law steady-state measurement method was adopted to conduct the stress-strain permeability experiment of coal and rock using the triaxial compression permeability experiment device. The experimental results show that the increase of confining pressure prevents the development of tensile crack, resulting in the increase of stress peak and permeability decrease of the total stress-strain curve of coal and rock. With the same confining pressure, the variation trend of the coal rock strain-permeability curve and the stress-strain curve is basically the same, and there is a causal relationship, resulting in the hysteresis of the coal rock strain-permeability curve compared with the stress-strain curve.

Keywords

• coal and rock permeability
• steady-state measurement
• stress-strain
• confining pressure
• hysteresis quality