Tests on swelling deformation of expansive soils;

Effect of swelling deformation on stability of expansive soil slope

This paper founds the relation of porosity, permeability and swelling deformation under considering swelling deformation made by coal adsorption gas, and by analysis it can be concluded that as gas stress in the coal bed increases, the swelling deformation becomes bigger, the porosity being much smaller, so as to weaken the permeability of the coal bed and make it difficult for gas flow.