The present invention discloses a novel underground
spray coating material and a preparation method thereof, and belongs to the technical field of mine protection
engineering. According to the present invention, a
polymer cement base
slurry comprises an additive,
cement and water, wherein a ratio of the additive and the
cement to the water is 1:1, and the additive comprises the following components, by weight, 50-65% of 425 cement, 15-23% of an
acrylic acid powder material, 5-8% of
gypsum powder, 3-6% of
calcium carbonate, 2-4% of a high strength water
reducing agent, 4-7% of an accelerated agent, and 1-2% of antifoaming agent. The preparation
spray coating method comprises material preparing, stirring,
spray coating and the like. According to the present invention, in the case of the same
viscosity of the
cement slurry, a spraying performance of the
polymer cement base
slurry is significantly improved; a bonding performance of the material and the surrounding rock is substantially improved; and compared to the ordinary
cement slurry, a tensile
bond strength of the cement base
slurry is increased by about 100-300%, and a 14 d
shear bond strength can be increased by 100-140%.