Influence of Mass Concentration on Microstructure and Pore Structure of Coal-Gangue-Based Green Cemented Filling Body

In response to China’s “double carbon” strategic goal, the problem of large emissions coal gangue and low utilization rate cemented backfill with fly ash as admixture needs be solved urgently. Based on this, this paper uses powder coarse fine aggregate prepare coal-gangue-based green filling body (CGGCFB) different mass concentrations (MC). The workability, mechanical properties, microscopic pore structure (nuclear magnetic resonance scanning electron microscope) were measured, respectively, explore effect MC above mentioned properties. terms macroscopic increase from 80% 82% 84%, slump slurry decreased by 18.37% 32.65%, expansion 30% 54.55%, bleeding 28.3% 60.38%. uniaxial compressive strength (UCS) CGGCFB at ages increased varying degrees, maximum was 2.9 times original. characteristics, total number pores decreases, size changes small, shape tends uniform circular, force characteristics are improved, complexity tortuousness channels increase, inner surface becomes rough; test results show that performance a concentration is reasonable, can 72%. research further improve resources, provide theoretical reference for application in mine filling.