Modular lightweight bridge girder erection machine and self-rapid transition method thereof

The invention discloses a modular lightweight bridge girder erection machine and an automatic rapid transition method thereof, and relates to the technical field of bridge construction.A front supporting leg, a middle supporting leg and a rear supporting leg are arranged on a main beam, each supporting leg comprises a telescopic supporting stand column and a steering base arranged at the lower end of the supporting stand column, and telescopic and rotary adjustment of the supporting legs is achieved; the main beam can be rapidly segmented and connected, the whole bridge erecting machine can get on and off the bridge by controlling rotation and stretching of the supporting legs, after the bridge erecting machine gets off the bridge, in-situ disassembly and rapid transition transportation of the bridge erecting machine are achieved by means of the transportation module vehicle and based on detachable arrangement of the main beam, the transition safety of the bridge erecting machine is guaranteed, and the constr