Rheological Properties and Consolidaiion Mechanism of Cemen--Fly Ash Cemented Gangue Backfill Material.

:F1y ash,cement,coal gangue and water are used as backfill materials to backfill in mine, which can not only reaiize the large-scale utiiizaiion of soiid waste resources, but ako effectively control the surface subsidence of the mine. In this study, the rheologccal properiies, mechanical properiies and hydration characteristics of cemented gangue backfill werestudeed. The rheologccal properties, compressive strength, hydration products and nicrostructure of gangue backfill werestudeed respectively. The results showed that when the content of 325 ordinary Portland cement was 15%, the content of low cakum lly ash !s more than 20%,and the mass concentration of slurry was kept above 77%,the minimum compressive strength of the prepared gangue backfill sample at 28 d curing age was more than 4. 229 MPa, which provided good roof support for underground backfill mining. Secondly, the influence of fly ash content and slurry mass concentrafion on the rheological properties of gangue filfing slurry were Investigated by rheological test, the corresponding rheologccal parameters and rheologcal equation fitting of filing slurry are obtamed. In addition, the mineral composition, hydration products and rmcrostructure of gangue cemented backfill materials were studied. Therefore, this study can provide some theoretical guidance for the apphcation of sohd waste n the ield of mine backi. [ABSTRACT FROM AUTHOR]