Main truss rear fulcrum bearing structure and cantilever bridge fabrication machine

The utility model discloses a main truss rear fulcrum bearing structure which comprises a bearing beam located below a beam body bottom plate, the bearing beam abuts against the beam body bottom plate, connecting pieces are arranged at the two ends of the bearing beam, and the connecting pieces are connected with a rear fulcrum of a main truss to apply downward acting force. The utility model further discloses a cantilever bridge fabrication machine which comprises the main truss and the main truss rear fulcrum bearing structure. An existing oil cylinder abutting against the beam body wing plate is omitted, and therefore the risk that the beam body wing plate is crushed is effectively avoided; the bearing beam is arranged below the beam body bottom plate and abuts against the beam body bottom plate, the two ends of the bearing beam are connected with the main truss through the connecting pieces, so that the counter force of a rear fulcrum of the main truss is borne by the beam body bottom plate, the beam body