Coal cleat permeability for gas movement under triaxial, non-zero lateral strain condition: A theoretical and experimental study

Abstract

As the permeability of coal seams is mainly determined by the network of natural fractures known as the cleat system, estimation of cleat permeability is of utmost importance for the carbon dioxide sequestration process indeep coal seams. The main objective of this study is to develop a new mathematical model for predicting cleat permeability under non-zero lateral strain conditions such as the conditions encountered in laboratory triaxial experiments. By applying the theory of elasticity to the constitutive behaviour of fractured rocks, a theoretical relationship between permeability and gas injecting pressure,confining pressure, axial load and gas adsorption intriaxial tests is developed. ..