Bridges
Curriculum Extension Unit
The engineering and construction of bridges has
been in a constant state of change since early man
first rolled a log across a stream to cross over to
the other side. The earliest bridges used a beam
of wood to span short distances. The Romans first
created the graceful arch bridge and then a
stronger material called concrete for bridges and
buildings. In the 19th century, the triangular truss
design stiffened bridge frames so they could span
greater distances. As the Industrial Age
introduced the need for stronger and longer
bridges to carry trains and automobiles, steel
suspension bridges added a new shape to the
horizon. During this unit, student engineers
experiment with balancing opposing forces using
various bridge designs and materials.