The invention relates to a long spiral double-
pipe high-pressure stir-jet grouting
pile construction method and a long spiral double-
pipe high-pressure stir-jet grouting
pile construction device. The method comprises the following steps of: according to the design requirements, determining the position of each
pile, and drilling while jetting water at the high speed to form a
slurry retaining wall, or jetting
cement slurry when necessary; or directly drilling; and lifting the
drill by adopting jet grouting, directional jet grouting or swing-jet grouting technology to perform stir-jet grouting until a pile is formed. The long spiral double-
pipe high-pressure stir-jet grouting pile device comprises a hollow
drill stem, a high-pressure
slurry conveying pipe, a high-pressure
water pipe, a stirring blade, a double-pipe jet grouting stirring
drill, a double-pipe rotary grouting joint, a
cement slurry conveying pipe, a high-pressure water conveying pipe, a high-pressure
cement grouting pump, a high-pressure water pump and the like. Compared with the conventional stirring pile and stir-jet grouting pile, the long spiral double-pipe high-pressure stir-jetting pile device is suitable for not only mollisol, loose or slightly compact sandy soil, but also various soil
layers, such as stiff clay, sandy gravel,
muck and the like, and particularly has more obvious effect in the sandy gravel.