Large-diameter cast-in-situ bored pile head overall breaking system and construction method

The invention belongs to the technical field of cast-in-situ pile construction. A large-diameter cast-in-situ bored pile head overall breaking system comprises a pile head separation support, isolation sleeves, a first counter-force frame, a second counter-force frame and a driving part, wherein the first counter-force frame and the second counter-force frame are correspondingly arranged up and down; the multiple isolation sleeves are arranged on the pile head separation support, longitudinal main ribs on the upper portion of a steel reinforcement cage of a cast-in-situ pile are arranged in the isolation sleeves in a matched and penetrating manner, and the pile head separation support and the isolation sleeves are poured on the top of the cast-in-situ pile; and a plurality of first counter-force holes are circumferentially distributed in a pile head of the cast-in-situ pile, a plurality of second counter-force holes are circumferentially distributed in the position, on the lower portion of the pile head separ