A preparation method for underground filling cementitious material, characterized in that it comprises the following steps: crushing 40-70 parts of waste glass, 30-40 parts of
slag and 10-20 parts of steel
slag to an average particle size of 1-15 mm, and mixing uniformly , to obtain a
solid mixture; water is added to the
solid mixture, the weight ratio of water to the
solid mixture is 0.4-0.6, and then 1-2 parts of water
reducing agent are added for
wet grinding, and the average particle size of the
ball mill until the
slurry is 1 ‑5 μm to obtain a liquid
slurry; add water to the liquid
slurry, the weight ratio of water to liquid slurry is 0.5, then add 3‑8 parts of activator, mix and stir evenly, and vibrate completely to obtain underground filling cementitious material . The invention utilizes the characteristic that the slurry is alkaline after
wet grinding, and the glass in the mixed slurry excites the
slag while completing the self-excitation, fully utilizes the solid waste, improves the
utilization rate of the solid waste, reduces the preparation cost, and is energy-saving and environment-friendly. The multifunctional, economical and efficient underground filling cementitious material is prepared, the preparation process is simple, and the
cement mortar can be gradually replaced and widely used.