Method for passing through bridge by using truck crane folding quay crane trapezoidal frame

The invention discloses a method for folding a quay crane trapezoid frame to pass through a bridge through a truck crane. The method comprises the following steps that S1, a hoisting lifting lug and a binding lifting lug are installed on the quay crane trapezoid frame; s2, the transport ship leans against a wharf, and the quay crane is dragged to the ship; s3, positioning the truck crane and adding a counter weight; s4, the front girder is upwards pulled up; s5, the truck crane lifts the partial load beam to the front girder, and one end of the supporting rod is connected to the binding lifting lug; s6, the front girder is lowered to the tower; s7, the automobile crane lifts the trapezoidal frame, the pin shaft on the pull rod is dismounted, and the trapezoidal frame is folded; s8, the other end of the supporting rod is connected to the front girder; s9, the transport ship starts to arrive at an unloading wharf; s10, positioning the truck crane and adding a counter weight; and S11, the automobile crane lifts