Adjustable soil body expansion head anchor rod drill bit

The utility model belongs to the technical field of engineering equipment, and particularly relates to an adjustable soil body expansion head anchor rod drill bit. The drill bit comprises a threaded rod, a drill bit body is arranged at the top of the threaded rod, and a drill rod fixing block is arranged above the drill bit body. According to the utility model, through the arrangement of the adjustable expanding and shrinking anchor rack assembly, when drilling holes with different hole diameters are dealt with in the buried drill reaming process, the diameter of the rod body between the drill rod fixing block and the drill bit body is adjusted by moving the adjustable expanding and shrinking anchor rack assembly towards one end close to or far away from the water outlet connecting pipe fitting; the anchor rod construction requirements under different drilling radiuses of the cover plate are adjusted by adjusting the drilling radius of the cover plate, the shearing strength between the rod body and the rock-s