The invention provides a hollow thread-shaped
drill bit suitable for super long screw
pile cast-in-situ construction in a soft foundation and a using method of the hollow thread-shaped
drill bit. The hollow thread-shaped
drill bit comprises a
pile shoe, a first hollow threaded drill rod, a plurality of second hollow threaded drill rods, a plurality of annular steel hoops and a plurality of pin bolts. In work, the lower end of the first hollow threaded drill rod is connected with the
pile shoe, and the upper end of the first hollow threaded drill rod is connected with the second hollow threaded drill rods or a rotary driving part of a drilling
machine. The lower end of each second hollow threaded drill rod is connected with the first hollow threaded drill rod or the adjacent second hollow threaded drill rods, and the upper end of each second hollow threaded drill rod is connected with the adjacent second hollow threaded drill rods or the rotary driving part of the drilling
machine. The using method of the hollow thread-shaped
drill bit comprises the steps of pile shoe fixing, first hollow threaded drill rod mounting, drilling, reverse rotation for
drill bit lifting and the like. According to the hollow thread-shaped
drill bit, the drilling tool
falling risk is avoided, the phenomena of hole collapse, hole shrinkage and the like are not prone to occurring in construction, the screw pile construction quality can be ensured, and the hollow thread-shaped drill bit suitable for super long screw pile cast-in-situ construction in the soft foundation and the using method of the hollow thread-shaped drill bit are specially suitable for screw pile construction in the soft foundation.