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.
Left communism is the range of communist viewpoints held by the communist left, which criticizes the political ideas and practices espousedâparticularly following the series of revolutions which brought the First World War to an endâby Bolsheviks and by social democrats.