Double-power down-the-hole hammer pipe-following drilling pile-forming construction method for cast-in-place pile in deep and thick rock-filled layer

The invention relates to the technical field of pile-forming construction methods, and discloses a double-power down-the-hole hammer follow-pipe drilling pile-forming construction method for a cast-in-place pile of a deep and thick rock-filled layer, which comprises the following steps: leveling a construction site, and placing a down-the-hole hammer drilling machine in place; the down-the-hole hammer drilling machine is provided with a drill rod, an inner through hole is formed in the drill rod, a down-the-hole hammer is arranged at the bottom of the drill rod, the drill rod is sleeved with a steel sleeve, and the inner through hole is communicated with an air compressor through an air inlet pipe. The outer side power head drives the steel sleeve to rotate, the steel sleeve drills in advance in the soil layer, high-pressure gas is injected into the inner through hole, the inner side power head drives the drill rod and the down-the-hole hammer to drill along with the pipe, and an upper layer hole is formed in