Double-slurry closing construction method for sump

The invention relates to a double-slurry closing construction method for a sump. The double-slurry closing construction method for the sump comprises the following steps that (1) a drilling machine platform is laid around the grouting position; (2) slurry is prepared, first slurry is composed of liquid A, liquid B and a first additive at the mass ratio of 1: 1: 0.13, and second slurry is composed of liquid A , liquid C and a second additive at the mass ratio of 1: 1: 0.17; (3) grouting holes are distributed; (4) a rotary drilling bit penetrates through the stratum by the designed hole depth of 4.5 m, then the first slurry is injected into the hole in a retreating mode, the grouting pressure is controlled to range from 0.5 Mpa to 1.0 Mpa, a drill rod retreats by one meter, the second slurry continues to be injected, the grouting pressure is controlled to range from 1.1 Mpa to 1.4 Mpa, the drill rod continues to retreat, and the steps are repeated in sequence; when only one meter of the drill rod is left through retreating, the first slurry is injected and then the next hole is grouted after completion of grouting; and (5) after the sump is dug in a grouted foundation, and the wall face of the sump is coated with waterproof paint. By the adoption of the double-slurry closing construction method for the sump, construction is rapid and convenient, the closing effect is good, and the method is suitable for the technical field of constructional engineering.