Roman bridge

Roman bridges, built by ancient Romans, were the first large and lasting bridges built. Roman bridges were built with stone and had the arch as the basic structure (see arch bridge). Most utilized concrete as well, which the Romans were the first to use for bridges.

Typology

As with the vault and the dome the Romans were the first to fully realize the potential of arches for bridge construction.

A list of Roman bridges compiled by the engineer Colin O'Connor features 330 Roman stone bridges for traffic, 34 Roman timber bridges and 54 Roman aqueduct bridges, a substantial part still standing and even used to carry vehicles. A more complete survey by the Italian scholar Vittorio Galliazzo found 931 Roman bridges, mostly of stone, in as many as 26 different countries (including former Yugoslavia; see right table).

Roman arch bridges were usually semicircular, although a few were segmental (such as Alconétar Bridge). A segmental arch is an arch that is less than a semicircle. The advantages of the segmental arch bridge were that it allowed great amounts of flood water to pass under it, which would prevent the bridge from being swept away during floods and the bridge itself could be more lightweight. Generally, Roman bridges featured wedge-shaped primary arch stones (voussoirs) of the same in size and shape. The Romans built both single spans and lengthy multiple arch aqueducts, such as the Pont du Gard and Segovia Aqueduct. Their bridges featured from an early time onwards flood openings in the piers, e.g. in the Pons Fabricius in Rome (62 BC), one of the world's oldest major bridges still standing. Roman engineers were the first and until the industrial revolution the only ones to construct bridges with concrete, which they called Opus caementicium. The outside was usually covered with brick or ashlar, as in the Alcántara bridge.

Roman Bridge (Chaves)

The Roman Bridge at Chaves, also known as Trajano bridge as a reference to Trajan, is an ancient bridge located in the north of Portugal in the town of the same name. The bridge which is in relatively good shape unites the two most important parishes in the town. The bridge is 140 meters long, high and has 12 visible arches. Although the bridge spanning the Minho in Ourense is longer and higher, this example of Roman architecture is even today a masterpiece of construction.

Two of the columns of the original bridge, built by the Emperor Trajan, still stand. They are stout cylindrical columns with details of the honors bestowed by the emperor on local governors or generals clearly legible on them. They were also milestones indicating distances to the important settlements of Astorga in Spanish León and Bracara Augusta, Braga, in Portugal.

History and construction

The bridge was built between the end of the first century and the beginning of the second century AD. Little is known about the exact dates of the beginning or conclusion of construction. However, it is known that slaves captured from the peoples inhabiting the region worked on the bridge. This appears to be written on one of the columns placed in the middle of the bridge. These columns were not here originally. One of them mentions the construction of the bridge, referring to the reign of the emperor Trajan; the other was taken from the Roman road leading up to the bridge. Before the building of the bridge the crossing was made by a road raised above the bed of the river, which only allowed the river to be crossed in summer.

Roman Bridge (Vaison-la-Romaine)

The Roman Bridge at Vaison-la-Romaine (French: Pont romain de Vaison-la-Romaine) is a Roman bridge over the river Ouvèze in the southern French town of Vaison-la-Romaine. The bridge was built by the Romans in the 1st century AD, with a single arch spanning 17.20 m. It is still in use, and has survived severe flooding that swept away some more recent bridges.

Sources

See also

External links

Media related to Roman Bridge (Vaison-la-Romaine) at Wikimedia Commons