Masonry bridge

A masonry arch bridge, typically designated as a masonry bridge, stone bridge, or vaulted bridge, represents a specific construction technique. However, it is primarily regarded as a prominent category of bridges, employed from antiquity until the early 20th century.
Masonry bridges represent a distinct category of arch bridges, distinguished by their tendency to experience supporting reactions on the abutments that tend to push them apart. The materials used for the arches are cut stones, exhibiting high compression resistance but limited flexion flexibility. In contrast, materials employed in other arch bridge types, including wood, concrete, reinforced concrete, prestressed concrete, metal, and composites, demonstrate some elasticity and can accommodate flexion, enabling the construction of bridges with greater spans.

History

The ancient period

Horizontal stone arches

The initial arches were constructed using horizontal stones arranged in an overlapping configuration, a technique referred to as "corbelling." In Abydos, within the palace of Ozymandias, whose reign dates back approximately 2,500 years BCE, a vault of this type was discovered. A similar construction can be observed in Thebes, within the temple of Amun-Ra. Nevertheless, this type's most notable ancient vault is arguably the Treasury of Atreus, an imposing tholos tomb in Mycenae, Greece, constructed circa 1250 BCE. The structure is a semi-subterranean chamber with a circular plan and an ogival section roof. With an interior height of 13.5 meters and a diameter of 14.5 meters, it was the largest and widest dome in the world for over a millennium, until the construction of the Baths of Mercury at Baiae and the Pantheon in Rome.

Mycenaean bridges

Three bridges remain in Argolis, in the Peloponnese, including the Mycenaean bridge of Kazarma. It was constructed using the corbelling technique, a method characterized by the rough stacking of stones.
These bridges were probably constructed around 1300 BCE, during the Mycenaean period, specifically during the Helladic IIIb phase. They were erected to facilitate transportation along the route connecting the prominent Mycenaean settlements of Mycenae, Argos, and Tiryns to the port of Palea Epidavros.

Converging joint arches

The use of converging joint arches, which are joints that are perpendicular to the intrados surface, is a characteristic feature of masonry bridges. These arches can already be observed in various monuments of ancient Egypt. In Nubia, one of the pyramids of Meroë contains a true semi-circular arch constructed with regularly arranged voussoirs. At Gebel Barkal, two porticoes leading to pyramids are covered, one by a pointed arch and the other by a semi-circular arch. Both are constructed with voussoirs featuring converging joints. Additionally, an elliptical barrel vault, crafted from bricks, can be observed in the tomb of Amenhotep I. This architectural feature dates back to approximately 1,800 BCE.
In more recent times one may observe the employment of this architectural construction principle of an arch in the Etruscan walls of the city of Volterra, which dates from the 3rd or 2nd century BCE.

The Roman period

It was the Romans who revived, perfected, and disseminated the arch technique throughout Europe for the construction of bridges. The vast extent of the Roman Empire necessitated the construction of reliable roadways that could be used throughout the year and were constructed with more substantial materials than those used for simple wooden bridges.

In Italy

It is widely accepted that the oldest known vaulted Roman structure is the Cloaca Maxima, a sewer constructed under the rule of Tarquinius Priscus around 600 BCE.
Roman bridges are characterized by their robust construction and the use of semi-circular arches, which are arches with a circular arc that rest on thick piers with a width approximately half the span of the arch.
File:Ponte Milvio-side view-antmoose.jpg|thumb|The Milvius bridge over the Tiber in Rome.
The Aemilius Bridge, now designated Ponte Rotto, is the oldest extant stone bridge in Rome. The bridge was constructed by Marcus Aemilius Lepidus in 179 BC and underwent numerous restorations, the most recent of which was conducted by Pope Gregory XIII in 1575. It features semi-circular arches with an opening of 24.40 meters and prominent archivolts, supported by thick piers measuring 8 meters in width. Between these piers, niches rise to the tympanum, flanked by columns with capitals. Currently, only a single arch remains intact.
One of the most ancient structures in Roman roadways is the Milvian Bridge, constructed over the Tiber by the consul Marcus Aemilius Scaurus in 115 BCE. Situated approximately three kilometers from Rome, where the Via Flaminia and the Via Cassia converge to traverse the river, the Milvian Bridge served as the obligatory gateway for those arriving from the north. Given its advantageous location, the Milvian Bridge became a focal point for numerous conflicts. In 312 CE, it was here that Emperor Constantine emerged triumphant over his rival Maxentius in the renowned Battle of the Milvian Bridge.
A considerable number of bridges were constructed in the Italian provinces, each exhibiting distinctive characteristics. Among these bridges is the Pont-Saint-Martin bridge, constructed over the Lys between 70 and 40 BCE at the entrance to the Aosta Valley. The single arch of the bridge has a span of 31.4 meters and a rise of 11.42 meters, which was unusually flat for the time. The structure features two different masonry techniques: the lower part is made of gneiss blocks, dry-laid, while the upper part is a superposition of layers made of gneiss flakes and lime, interspersed with bands of stone.
The Fabricius Bridge, constructed in 62 BCE by the road commissioner Lucius Fabricius, is the sole surviving ancient Roman bridge in Rome that has remained in its original state. It spans the Tiber River, connecting Tiber Island to the Campus Martius shore, situated close to the Theater of Marcellus and the Forum Boarium.
Another ancient Roman bridge is the Saint Angelo Bridge, which connects the two banks of the Tiber opposite the Castel Sant'Angelo. Construction of the bridge commenced in 134 CE under the reign of Emperor Hadrian, who subsequently bestowed upon it the name Pons Aelius.

In the West, outside Italy

Spain and Portugal are home to some impressive Roman bridges, the majority of which were constructed during the Augustan period. The Roman bridge of Mérida in Extremadura, comprising 60 arches that traverse the Guadiana River, has a length of 792 meters. The Alcántara Bridge, constructed over the Tagus between 103 and 104 CE, features six semi-circular arches with openings ranging from 30.8 to 43.6 meters. These arches are supported by piers that are approximately 9 meters thick. Some of the piers are situated in the river itself and rise to a height of approximately 40 meters above their foundations. The bridge's aesthetic appeal is derived from its imposing dimensions, the simplicity of its structural forms, and its solid appearance.
Two noteworthy aqueduct bridges from this period are the Segovia Aqueduct, constructed between 98 and 117 CE under the direction of Trajan, and the Aqueduct of Tarragona. The Segovia Aqueduct is 813 meters in length and features 128 arches, while the Aqueduct of Tarragona spans the Francolí Valley and is 217 meters in length.
In the 3rd century, segmental arch bridges, or flat arch bridges, emerged. One of the earliest examples of this type of bridge is the Limyra Bridge, situated near Limyra in present-day Turkey. It is 360 meters in length and comprises 26 segmental arches and two semi-circular arches.
In France, the Pont du Gard is a Roman aqueduct bridge comprising three levels, with a maximum height of 47.40 meters at its highest point. It is situated in the commune of Vers-Pont-du-Gard, in the Gard department. It was probably constructed during the first half of the 1st century, serving to maintain the continuity of the Roman aqueduct that transported water from Uzès to Nîmes, a distance of 50 kilometers.

In the East

It is almost certain that the Chinese independently invented the arch, either before or after the Greeks, and that they constructed vaulted bridges at an early date, possibly even before the Romans. According to Chinese archaeologists, the oldest bridge is the Lurenqiao Bridge, constructed around 282 BCE near the ancient palace of Luoyang.
The Zhaozhou Bridge, which bears a resemblance to 19th-century Western bridges, was constructed around 605 CE. It is the oldest segmental arch bridge with an open spandrel in the world and the oldest bridge in China still in use. It is situated in the Zhao District of the prefecture-level city of Shijiazhuang in Hebei. The span of its arch measures 37.4 meters.
Another noteworthy ancient bridge is the Baodai Bridge, constructed over the Grand Canal in Suzhou by Wang Zhongshu, governor of Suzhou during the Tang dynasty. It is 317 meters in length and comprises 53 arches, making it the Chinese bridge with the greatest number of arches.

The Medieval period

In the West

Following the decline of the Roman Empire, a period of approximately five centuries, or half of the millennium, was characterized by the dominance of the Middle Ages. During this era, which saw the rise of the Church and the development of feudalism, there was a paucity of significant artistic and architectural works. The construction of bridges, in particular, was largely confined to wooden structures.
File:Avignon pont 2.jpg|left|thumb|Avignon bridge over the Rhône, with pointed arches.
From the 11th century onwards, a plethora of bridges of varying shapes were constructed. These structures frequently comprised arches of varying degrees of unevenness, with vaults in slightly flattened curves, semicircular arches, or pointed arches, the latter of which diminished pressure on the structure. They were supported by thick piers with protruding ends, at least upstream. The distances between walls were narrow, and the passages were marked by steep ramps and slopes.
In France several noteworthy medieval bridges can be found, including the Pont Saint-Bénézet in Avignon on the Rhône, the historic bridge in Carcassonne on the Aude. Additionally, the Petit-Pont in Paris on the Seine, the Pont Valentré in Cahors on the Lot, and the Pont Saint-Martial in Limoges on the Vienne are noteworthy examples.
The Middle Ages saw the construction of numerous wooden bridges, many of which were topped with structures that served as shops, thereby creating what are known as inhabited bridges. One of the most renowned examples is the Ponte Vecchio on the Arno River in Florence, Italy. Originally constructed from wood, it was subsequently rebuilt in stone in 1345 by either Taddeo Gaddi or, depending on the source. However, it was not until the 16th century that the renowned gallery above the shops was constructed.