Method for improving permeability of granite residual soil

The invention belongs to the technical field of foundation reinforcement, and particularly relates to a method for improving the permeability of granite residual soil. The method comprises the steps that reaction liquid and stationary liquid are sequentially poured into the granite residual soil; the reaction liquid is prepared from 0.2 g/L-4. 0g/L of starch, 0.8 g/L-10 g/L of glucose, 0.4 g/L-5. 0g/L of peptone, 0.2 g/L-10.0 g/L of yeast extract, 0.3 g/L-6. 0g/L of sodium chloride, 0.2 g/L-5. 0g/L of dipotassium phosphate and water, and the stationary liquid is prepared from 0.2 mol/L-1. 5mol/L of urea and water. According to the method for improving the permeability of the granite residual soil, under the action of nutrient substances in the reaction liquid, microorganisms in the granite residual soil are massively proliferated, extracellular polymers are generated, soil particles are aggregated and adhered by organic matter, and under the action of urease generated by the microorganisms, the permeability o