The invention discloses a cast-in-situ bored
pile hole-forming device and method.
Dirt slurry at the hole bottom is conveyed to a coarse screening device through a drilling rod by means of a gravel pump, a coarse
slag material flows into a coarse screening
slag material
pool after the
dirt slurry is subject to coarse screening through the coarse screening device, and the rest of the
dirt slurry flows into a slurry
storage tank; the slurry in the slurry
storage tank is conveyed to a
hydrocyclone through a
slag slurry pump and is subject to fine screening through the
hydrocyclone, then a fine slag material flows into a fine screening slag material
pool, and the rest of the slurry flows into a middle
storage tank; and the slurry inside the middle storage tank is conveyed to space between the drilling rod and the hole wall by an overflowing opening formed in the
pool wall or through a
slurry pump, and therefore a reverse circulation loop is formed. By adopting a pumping suction reverse circulation hole cleaning manner, the hole-forming rate and the hole cleaning efficiency can be improved, the waste slurry
discharge amount is less, the single-
pile construction time is shortened, the inward contraction amount of the hole wall is reduced, and the construction quality is improved. By means of two-stage screening through the coarse screening device and the
hydrocyclone, the quality of slurry circulated back to holes can be improved, slag sinking to the hole bottom is further reduced effectively, and the hole wall is more stable.