Pneumatic down-the-hole hammer vibration jet grouting pile inserted steel pipe composite foundation and pile foundation construction method

The invention discloses a pneumatic down-the-hole hammer vibration jet grouting pile inserted steel pipe composite foundation and a pile foundation construction method. The construction method comprises the steps that drilling is conducted; after drilling to the designed depth, a water pump of the drilling machine is switched into a high-pressure pump to pump cement paste, the high-pressure paste is subjected to high-pressure air jet grouting, vibrated and lifted, and the jet grouting pile is formed; a steel pipe is inserted into the center of the pile to form a stiffened core cement soil steel pipe pile; and the steps are repeated, a plurality of stiffening core cement soil steel pipe piles are constructed at intervals according to the design, and a composite foundation or a steel pipe pile foundation is formed. The method has the advantages that the application range is wide, the construction speed is high, the bearing capacity and settlement deformation requirements can be met, and the comprehensive cost i