Drilling bit for engineering investigation and drilling construction of gravel soil layer

The invention discloses a drilling bit for engineering investigation and drilling construction of a gravel soil layer. The drilling bit comprises a drilling base plate, a moving mechanism, a stabilizing mechanism, a placing box body, a collecting box body, a fixed block, a telescopic oil cylinder, a rotating plate, a protection mechanism, a cleaning mechanism and a support plate, wherein the moving mechanism is installed on the lower end of the drilling base plate, a mounting plate, the stabilizing mechanism, the placing box body, the collecting box body and the support plate are installed on the upper end of the drilling base plate, the stabilizing mechanism, the placing box body and the support plate are all located between the mounting plate and the collecting box body, the collecting box body is located on one side of the mounting plate, and the stabilizing mechanism is located between the placing box body and the support plate. According to the drilling bit, the elastic preloads of a reset spring I and a