Study on cement-coal refuse backfill structure model of mining goaf in underground mine

Due to the high cost of the present cement as the main cementation composition of the backfill material, the cement was not suitable the backfill mining with a larger area. In order to realize the solid waste to replace the cement based high efficient backfill material in the mining goaf, based on the cement and coal refus e as the main composition of the backfill material, a relationship between the compressive strength of the backfill and the cement volume mixed was obtained from the | ab experiments. A scanning electron microscopy was applied to the observation on the micro structure of the backfill. The compressive strength increased law of the ba ckfill with different cement volume mixed was analyzed. A structure model of the cement- coal refuse backfill was established. The study results showed that the cement . coal refuse backfill structure was consisted of the coal refuse particle cementation and the pore backill and the coal refuse particle cementation and the pore backfill could play a high role to improve the compressive strength of the backill.