Drilling construction device for building foundation

The invention provides a building foundation drilling construction device, and relates to the technical field of building construction device.The construction device comprises a drill rod and a drill bit, the drill bit comprises a connecting plate which is perpendicular to the axis of the drill rod and rotationally arranged at the end of the drill rod, and at least one set of force transmission assembly is arranged between the connecting plate and the drill rod and surrounds the drill rod; the force transmission assembly comprises a force bearing face and a force application rod which are arranged on the connecting plate and the drill rod respectively, and the axis of the force application rod intersects with the connecting plate. The end, away from the force bearing face, of the force application rod is provided with an impact assembly, and the impact assembly is configured to be triggered when the force between the force application rod and the force bearing face is larger than a preset value so as to drive