Rock-filled layer grading reaming and hard rock center coring hob drilling construction equipment

The utility model relates to the technical field of large-diameter pile construction, and discloses rockfill layer grading reaming and hard rock center coring hob drilling construction equipment which comprises a rotary drilling rig and a pre-opening drilling bucket cooperating with the rotary drilling rig to form a pre-opening hole section in a soil filling layer in a rotary excavating mode. The steel sleeve is embedded downwards through the pre-trepanning section, and the grading drilling bucket and the cone barrel drill are cooperated with the rotary drilling rig to conduct grading rotary drilling downwards on the pre-trepanning section to form soil layer holes. The bottom of the steel sleeve extends downwards to penetrate through the soil filling layer and the rock filling layer and is embedded into the clay layer, and the bottom of the soil layer hole extends to the top of the hard rock section; the cone barrel drill is used for cooperating with the rotary drilling rig to conduct coring drilling on a har