METHOD FOR CONCRETING LOOSE SAND PARTICLES THROUGH BIOLOGICAL PHOSPHATE AND CARBONATE COMPOSITE CEMENTING MATERIAL

摘要

Disclosed is a method for concreting loose sand particles through a biological phosphate and carbonate composite cementing material, comprising the following steps: inoculating the second to third-generation Bacillus pasteurii strains into a soy peptone and casein peptone culture medium, thereby obtaining the third to fourth-generation Bacillus pasteurii bacterium solution; then completely dissolving K₂HPO₄ solids in the Bacillus pasteurii bacterium solution, thereby forming a phosphate bacterium solution; preparing a mixed solution of 1 mol/L of urea and 2 mol/L of anhydrous MgCl₂; preparing two grades of quartz sand with particle sizes below 150 μm and 150-300 μm according to a Fuller closest packing method and then filling the quartz sand in a mold provided with a buffer pad and filter sand; respectively injecting the phosphate bacterium solution and the mixed solution into the prepared quartz sand mold at a volume ratio of 1:1 via a peristaltic pump, until the phosphate bacterium solution and the mixed solution cannot be injected; and maintaining the sample with the mold in a drying oven for 10-15 days and performing form stripping, thereby obtaining corresponding quartz sand columns.