Bridges presentation
Structural
evolution achieved by Roman engineers is manifest in aqueducts, dam construction, and highway
bridges that relied on the development of concrete, and a growing awareness of its strength.
The Romans mixed a cement, pozzolana, found near the Italian town of Pozzuoli (ancient Puteoli),
with lime, sand, and water to form a mortar that did not disintegrate when exposed to water. It was
used as a binder in piers and arch spandrels, and mass-formed in foundations. Coffer dams
(temporary enclosures built in river beds to keep the water out while the foundations were
established) were made by driving timber piles into the river bed, removing water from the area
enclosed, and then excavating the soft ground inside. Despite the use of coffer dams, Roman bridge
foundations typically were not deep enough to provide sufficient protection against scour. Most of
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