The invention relates to the field of
tunnel construction engineering, in particular to a variable-
diameter full-section
cutting cutterhead and a using method thereof. Comprising a fixing ring which can be fixed at the front end of the
shield tunneling machine; one ends of the cutter spokes are connected to the outer side of the fixing ring, and the included angles between the adjacent cutter spokes are equal; the plurality of hobs are rotatably arranged on the cutter spokes and the fixing ring; each cutter
spoke is provided with one
cutting tool bit, and the
cutting tool bits can move in the axial direction of the cutter spokes; the driving mechanism is arranged on the cutter spokes, connected with the
cutting tool bits and used for driving the
cutting tool bits to move; the plurality of arc-shaped inner-layer ring beams are connected between the adjacent cutter spokes, and the plurality of inner-layer ring beams enclose to form a circular ring; and the
control system is in control connection with the driving mechanism. The variable-cross-section tunnel excavation device has the beneficial effects that the movable
cutting tool bits are arranged on the cutter spokes, the
moving speed, the moving direction and the moving
stroke of the cutting tool bits are controlled through the driving mechanism, the cutting range of the cutting tool bits is changed, and therefore excavation of a variable-cross-section tunnel is achieved.