The invention discloses an
underwater anti-sliding cast-in-situ bored
pile foundation and a construction method thereof. The
underwater anti-sliding cast-in-situ bored
pile foundation is used for
underwater soft soil slopes on river alluvial plains, river estuaries and continental shelves, and is formed by sequentially sealing and connecting at least one section of novel steel protection
barrel and at least one section of common steel protection
barrel from bottom to top. The novel steel protection
barrel comprises an inner barrel, an outer barrel and an automatic hole pressure adjusting
system, through holes are evenly distributed in the barrel wall of the outer barrel in the circumferential direction, and the through holes are located in an underwater soft soil layer. According to the underwater anti-sliding cast-in-situ bored
pile foundation and the construction method thereof, the
pore water pressure in
peripheral soil can be automatically adjusted at the construction stage and theoperation stage of the underwater anti-sliding cast-in-situ bored pile foundation; when penetration of the steel protection barrel in the construction process is difficult, pressurized water injection is carried out in a cavity of the novel steel protection barrel, the
peripheral soil is softened, the penetration resistance of the steel protection barrel is reduced, and the mounting efficiency isimproved; and when the super-static
pore water pressure in the operation process exceeds a
pore water pressure prewarning value capable of causing soil shear failure, an alarm gives an alarm, and a water pump is started to draw water.