Pore-fractal-permeability model and its experimental analysis of construction waste filling body with high fine-particle content

Construction waste with more fine particle occupies the amount of land and the utilization rate is low. Using fine-particle construction waste to fill mining gob is an effective way to release land resources and to slow down surface subsidence in mine area. The permeability of filling body is the key factor to affect the geological environment and regional hydrological cycle of filling gob. The paper analyzed respectively the components of fine particle and large-size particle of construction waste by the diffraction analysis, explored the formation mechanism of seepage pore in construction waste samples containing more fine particle, characterized quantitatively the porosity and seepage path of the samples by Matlab binaryzation and mass fractal dimension respectively, established the pore-fractal-permeability model of construction waste filling samples containing more fine particle, and verified the model by experiment. The study showed that the permeability weakened with the increase of < 2 mm particle (fine-particle) content. Permeability coefficient of the samples containing 15