Translations:Adventist Youth Honors Answer Book/Arts and Crafts/Bridges/33/en
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Beam bridge spans rarely exceed 250 feet (76 m) long, as the flexural stresses increase proportional to the square of the length (and deflection increases proportional to the 4th power of the length). However, the main span of the Rio-Niteroi Bridge, Brazil, a box girder bridge, is 300 metres/980 ft.