Soft rock stratum drilling and grouting reinforcement structure and method

The invention relates to a soft rock stratum drilling and grouting reinforcement structure and method, and belongs to the field of tunnel construction. The structure comprises a radial tree-shaped drilling net with a main hole as a trunk and a sub hole as a branch, the main hole penetrates to a soft rock stratum, and the sub hole is formed in the soft rock stratum; the method comprises the steps that S1, a horizontal female hole is drilled; s2, a plurality of sub-holes are drilled in the radial direction of the main hole, and a sub-hole net is formed; and S3, slurry is injected into the primary hole and the secondary hole. Wherein a drilling machine, a high-pressure pump, a high-pressure hose, a guider and a self-propelled drill bit are used for drilling a primary hole net and a secondary hole net, then a grouting pipe is used for grouting the primary hole net and the secondary hole net, and after grout is solidified, the solidification strength is achieved, so that the effect of reinforcing the soft rock str