ABSTRACT
The method of gas permeability measurement in triaxial state of stress by means of triaxial cell KTK100 was developed in the Institute of Geonics. The series of measurement were made to find the parameters influencing the gas permeability. The changes of permeability of coal samples during deformation process even after post-failure part were determined. The specimens were tested either in increasing confining pressures (from 5 to 50 MPa) or with constant confining pressure and increasing axial stress.
