Construction method for large-diameter super-long rotary excavating cast-in-situ bored pile of highway bridge in complex geology

The invention relates to the technical field of building construction, in particular to a complex geological highway bridge large-diameter super-long rotary excavating cast-in-situ bored pile construction method which comprises the following steps: sequentially performing construction preparation, surveying, paying off and embedding auxiliary piles and drilling machine in-place operation on a construction site; the construction site is sequentially subjected to pile casing installation, drilling and hole forming, hole cleaning and machine moving operation; the construction method comprises the following steps: sequentially hoisting a reinforcement cage, hoisting a guide pipe, pouring underwater concrete and pulling a pile casing on a construction site, carrying out dry operation and one-time hole forming by adopting long spiral drilling equipment, and integrally embedding the pile casing of a pile foundation through a rotary drilling machine during the period; before the reinforcement cage is hoisted, a reinf