The four kinds of bridges and some combinations
A. The beam or truss bridge is, in effect, a pair of girders supporting a deck spanning the gap between two piers.
has to withstand both compression in its upper parts and tension in its lower parts
may be a hollow box girder or an open frame or truss
| Simple Truss (or Beam) bridges |
B. An arch bridge can be designed so that no part of it has to withstand tension.
C. A suspension bridge consists, basically, of a deck suspended from cables slung between high towers.
The towers are in compression and the deck, often consisting of a long slender truss (used as a hollow beam), is supported at frequent intervals along its length.
D. A cantilever bridge is generally carried by two beams, each supported at one end.
must resist tension in its upper half and compression in its lower
the first modern cable-stayed bridges
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