In the case of a truss bridge, a post-tensioned slab bridge, or a box girder bridge the sections are often floated to the bridge and then lifted into place by cranes on barges or cranes sitting over piers.
The very good reason why the word communism is so commonly associated with these revolutionary, anti-liberal, anti-democratic Marxists is that political parties with communist in the name were pretty much invariably of that bent throughout the 20th century, whereas parties called socialist or social democrat or labor varied enormously in ideology.
In political and social sciences , communism ( from Latin communis ,  common , universal  ) is a social , political , and economic ideology and movement whose ultimate goal is the establishment of the communist society , which is a socioeconomic order structured upon the common ownership of the means of production and the absence of social classes ...