Vacuum preloading technology for ultra soft soils with footed-in filter tubes and its field tests

A new vacuum preloading technology for ultra soft soils with footed-in filter tubes is verified through field tests. Compared with the construction technology reinforcement effect and engineering cost of the conventional vacuum preloading technology for surface-layer of ultra soft soils, the new technology is characterized by simple construction technology, low cost and good reinforcement effect. The technology is worthy of being widely spread. Smaller distance of drainage plates (0.4~0.6 m) in newly reclaimed ground can effectively improve the reinforcement effect and reduce consolidation time. The technology has successfully solved the problem that ultra soft foundation has large settlement but low strength increase after reinforcement.