This method was first used in1976It has been widely used in the United States, Canada, Germany, France, Singapore, Thailand and other countries, as well as Hong Kong, and in China2010It was listed in the Construction Industry 10 A new technology (2010).

SMWmethod The main characteristics are simple structure, good water stop performance, short construction period, low cost, small environmental pollution, especially suitable for deep foundation pit engineering in the city. Construction is basically no noise, little impact on the surrounding environment, reliable structural strength, all suitable for the application of cement mixing pile can be used, especially suitable for clay and fine sand based soft strata; Waterproof performance is good, do not have to set another waterproof curtain, can be used in deep foundation pit with multiple support; This construction method can replace the diaphragm wall as underground enclosure under certain conditions, and the cost can be successfully recovered by taking certain construction measures H The cost of section steel and other materials is much lower than that of diaphragm wall while reducing the cost, so it has a great development prospect.

(1) Deep foundation pit projects built in modern cities are often constructed close to the red line of buildings,SMWThe construction method has a considerable advantage in this respect, its center line away from the wall of the building80Centimeters can be constructed.

(2) The diaphragm wall is determined by its own characteristics. A large amount of mud is formed during construction and needs to be transported outsideSMWOnly in the groove when a small amount of earth transport.

(3) SMWThe construction method is simple in structure and fast in construction speed, which can greatly shorten the construction period.

(4) SMWThe construction method separates the envelope structure from the main structure, and the side wall of the main structure can be waterproof outside construction. Compared with the underground diaphragm wall, the structural integrity and waterproof performance are better, which can reduce the later maintenance cost.

(5) Part of theHSection steel can be recycled for reuse.

Sealing curtain technology of mixing pile in ultra-deep and ultra-hard stratum:

With the increasing depth of the foundation pit, the sealing curtain must be used to cut off the confined water layer in the deep stratum30Meters above the super deepSMWMethod. Conventional deep SMW The construction method adopts the form of drill pipe construction, construction efficiency is very low, the cost is expensive, the quality of pile is not good, the construction period is long, easy to bury.

Strong foundation developedJB280typeSMWConstruction pile machine, realized45 The pile is formed at one time without connecting rod within meters, and the continuous grouting makes the pile quality more reliable and improves the working efficiency 3~4Times, reduce the project cost up to50%, shorten the construction period.