The project is located in the 7# mud pond of the deep water channel expansion project of Dayaowan Port Area in Dalian City. On the original land reclamation site, 1:1 slope is set to excavate 4 pour pits of 25×25m. The engineering innovation adopts the construction workmanship of “forced mixing + industrial filling pump transporting + underwater concrete pouring”, and applied the JCW soft soil cement independently researched and developed by our company, to conduct an island pouring and building pilot test with flow solidified soil, with a total of 4000m3 of poured flow solidified soil. The cured soil after 28 days met the bearing capacity requirement of 400kPa. The project comprehensively solved the following problems as: large amount dredged sludge is difficult to treat; the source of artificial island building materials is difficult to acquire; the traditional foundation treatment period is long, and also avoided the environmental pollution caused by sludge dumping and mountain excavating for soil and stone. It is the first large-scale application of dredged sludge flow solidified soil in China, and has achieved significant economic, social and ecological benefits.