Study of the effects of an ionic stabilizer on the permeability of gangue bonding material

Abstract

Gangue has been widely used in road engineering, but its relatively poor permeability restricts its further application in roads in cold areas. The effects of the ionic stabilizer (ICS) mixing amount on the adsorbed water characteristics, pore structure, morphology characteristics, surface element changes and cation exchange capacity of coal gangue were investigated by thermogravimetric analysis (TG), mercury intrusion porosimetry (MIP), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), the barium chloride buffer solution method and inductively coupled plasma optical emission spectrometer (ICP-OES), and the mechanism of ICS action was investigated. In addition, the permeability properties, shear strength and fractal characteristics of the pore structure of ICS-stabilized gangue bonding material were investigated. The results show that the strong cations and alkyl sulfonate radicals ionized in ICS aqueous solution will exchange and bind the cations on the surface of gangue mineral particles, weaken the electrostatic force of colloids and hydrophilicity of gangue, and then reduce the content of surface bound water. The pore size of gangue is smaller, the porosity is reduced, and the complexity of the pore structure is decreased after stabilization under the same external force, resulting in a smaller permeability coefficient and fractal dimension (Ds) values and greater cohesion. In addition, there is a linear relationship between Ds and the permeability coefficient, so Ds can be used as a new parameter to evaluate the permeability performance of coal gangue binding materials.