Page 3 - LetsUsMakeABridge

construction. She would meet with the engineers at the bridge site, and then return to her husband's
bedside, bringing him news and questions. Emily oversaw the completion of the bridge, and Washington,
who orchestrated the construction, never left his bed the whole time the Brooklyn Bridge was built.

Anatomy of a Bridge

Deck - For pedestrian, train, and/or automobile traffic.
Supports - The towers are the supports.
Span - Describes the distance between towers.
Foundations - The supports rest on the foundations.
Approaches - The approaches are the roads leading up to the bridge.
Long wire cables are strung over the towers and secured to the anchors on land.
Hangers run from the cables to the deck hold it up.

How They Work

Any bridge can only stay up if it can support its own weight (called the dead load) and the weight of all
the traffic that crosses it (called the live load). The load creates 2 major forces that act on parts of a
bridge. The 2 forces are Compression and Tension:

Compression - The force of compression pushes down on the suspension bridge's deck. but because
its a suspended roadway, the cables transfer the compression to the towers, which dissipate the
compression directly into the earth where they're firmly entrenched.

Tension - The supporting cables, running between 2
anchorages, are the lucky recipients of the tension forces.
The cables are literally stretched from the weight of the
bridge and its traffic as they run from anchorage to
anchorage. The anchorages are also under tension, but
since they, like the towers, are held firmly to the earth, the
tension they experience is dissipated.

Suspension bridges are capable of spanning long distances
and actually are the only type of bridge to span the longest
distances possible for a bridge. This is because the shape
of the suspension bridge is actually one of the most stable