Composite bridge launching Legionowo, Poland, 2008 | Construction methods| on-site Incremental launching of the composite bridge over railway. Cross section of 4 steel girders and 250mm reinforced concrete top slab. Structure launched with continuous RC slab to avoid closing of the railway for concreting the deck. Deck steel girders used as a launching nose (no auxiliary launching nose required). Railway line was in operation throughout whole duration of works.