Reinforcing and treating method for water burst of soft-flow muddy stratum of foundation pit

The invention discloses a reinforcing and treating method for a water burst of a soft-flow muddy stratum of a foundation pit. The method includes the following steps that firstly, the hydrogeological condition of a region is detected and a grouting treatment region is divided according to engineering requirements; secondly, when the soft-flow muddy stratum is excavated, mold bag grouting pipes are installed in the grouting treatment region at set intervals in a set arrangement mode, paste is injected in filter cloth bags in the mold bag grouting pipes, the filter cloth bags expand due to the injected paste, a surrounding soft soil stratum is then compacted, and after the paste in the filter cloth bags is hardened, a grouting stop layer is formed by the hardened paste and surrounding compacted soil jointly; and thirdly, soft soil strata located below the grouting stop layer are grouted and reinforced through grouting screen pipes of the mold bag grouting pipes.