Launching gantry (lg) is used in the erection of full span concrete pre-cast box girder for high speed railway bridges. They combine with a tyre trolley for concrete box girder erection. A lg can be used for normal concrete box girder erection as well as first span and last span erection, curve construction, various box girder sizes and short distance self-launching capability, ideal for limited space without the need for additional equipment. A lg can easily be dismantled for transfer between sites and can be transported by multi-axle trailer over viaducts, embankments and through long stretch tunnels