*_Great video... comprehensive yet understandable to average non-engineer..._* One thing all these different bridge types have in common is they must resist gravity. The larger and heavier the bridge, the sturdier it has to be. And, all of them look easy to build on paper. Site prep can be extensive. Some civil projects require constructing roads to the building site. Many areas in Japan and Chine have rugged terrain. Cut and fill, retaining structures, drainage, etc all have to be done before the bridge can even be started. *_We have 'Floating Bridges' across Lake Washington in Seattle. Who says thousands of tons of Concrete can't float?_*
