The invention provides a method for reinforcing a
sludge sand layer. The method comprises the following steps that S1, a
drill bit part of a stirring drilling
machine drills towards the
sludge sand layer, in the drilling process, stirring blades are opened and stir the
sludge sand layer, meanwhile, grouting equipment sprays
cement grout into the sludge sand layer through a
grout inlet hole, a
liquid injection cavity of a
drill rod and a grouting hole, and the
cement grout and the sludge sand layer are mixed and condensed into a
cement reinforcing body; S2, the
drill bit part retreats from the sludge sand layer, in the retreating process, the stirring blades are retracted, and meanwhile, the
cement grout provided by the grouting equipment is sprayed into a hole drilled by the
drill bit part through the grouting hole and blocks the hole; S3, the stirring drilling
machine is moved to the next to-be-reinforced position, and the steps S1 and S2 are repeated; S4, a re-reinforcing hole is drilled in the cement reinforcing body, and a long anchor
pipe is inserted into the re-reinforcing hole; and S5, the
cement grout provided by the grouting equipment is grouted into the re-reinforcing hole through the long anchor
pipe and permeates into gaps of the cement reinforcing body.