Abstract: For the problem of difficult roof anchor withdrawal at the end of a working face, a static crushing directional anchor withdrawal method at the end of a large-mining-height working face is provided. The method includes the following steps: designing key parameters of boreholes for static crushing, including a borehole position, a spacing between boreholes, a borehole depth, and a borehole diameter at the end of a working face; then determining parameters of a static crushing agent grouting technology device for the construction of a static crushing process; and carrying out an anchor withdrawal operation at the end.

Abstract: A fluidized solidified soil based on gold tailings includes the following raw materials in parts by mass: 75 parts to 80 parts of gold tailings, 5.2 parts to 13 parts of a dispersant solution, and 9 parts to 16 parts of a solidifying material. A preparation method includes the following steps: mixing the gold tailings with the dispersant solution, and then stirring to obtain a suspension slurry of the gold tailings; and adding the solidifying material, and stirring to obtain the fluidized solidified soil. In the present disclosure, the gold tailings are used as a main material, combined with a special dispersant solution and a special solidifying material, and a fluidized solidified soil is prepared with fluidity suitable for pumping and a certain strength after hardening. The fluidized solidified soil prevents the pollution caused by gold tailings landfilling, and can be used as a filling material for various construction projects.

Abstract: A dispersant for premixed fluidized solidified soil includes the following raw materials in parts by weight: 5 parts to 15 parts of an anti-adhesion water reducer, 0.5 parts to 0.8 parts of a stabilizer, and 85 parts to 95 parts of water. The anti-adhesion water reducer is compounded by an inorganic dispersant and an aminosulfonic acid-based superplasticizer (ASP), and the inorganic dispersant is at least one selected from the group consisting of sodium silicate, sodium hexametaphosphate, and sodium pyrophosphate. In the present disclosure, on the premise of improving fluidity of mucky cohesive soil slurry, a strength of the fluidized solidified soil at each stage is adjusted through a water-reducing effect of the anti-adhesion water reducer. Moreover, rapid dispersion of the mucky cohesive soil slurry is realized, thus providing key technical support for preparation of the premixed fluidized solidified soil from undisturbed soil in non-dry conditions.

Abstract: A dispersant for premixed fluidized solidified soil includes the following raw materials in parts by weight: 5 parts to 15 parts of an anti-adhesion water reducer, 0.5 parts to 0.8 parts of a stabilizer, and 85 parts to 95 parts of water. The anti-adhesion water reducer is compounded by an inorganic dispersant and an aminosulfonic acid-based superplasticizer (ASP), and the inorganic dispersant is at least one selected from the group consisting of sodium silicate, sodium hexametaphosphate, and sodium pyrophosphate. In the present disclosure, on the premise of improving fluidity of mucky cohesive soil slurry, a strength of the fluidized solidified soil at each stage is adjusted through a water-reducing effect of the anti-adhesion water reducer. Moreover, rapid dispersion of the mucky cohesive soil slurry is realized, thus providing key technical support for preparation of the premixed fluidized solidified soil from undisturbed soil in non-dry conditions.

Abstract: A fluidized solidified soil based on gold tailings includes the following raw materials in parts by mass: 75 parts to 80 parts of gold tailings, 5.2 parts to 13 parts of a dispersant solution, and 9 parts to 16 parts of a solidifying material. A preparation method includes the following steps: mixing the gold tailings with the dispersant solution, and then stirring to obtain a suspension slurry of the gold tailings; and adding the solidifying material, and stirring to obtain the fluidized solidified soil. In the present disclosure, the gold tailings are used as a main material, combined with a special dispersant solution and a special solidifying material, and a fluidized solidified soil is prepared with fluidity suitable for pumping and a certain strength after hardening. The fluidized solidified soil prevents the pollution caused by gold tailings landfilling, and can be used as a filling material for various construction projects.