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45-399: The Satakunta Bridge was designed by engineer Karl Snellman , son of Senator J. V. Snellman . It was built between 1897 and 1900 and commissioned on October 9, 1900. The bridge is a 6-span stone arch bridge with spans of 17 meters. The width of the bridge is 11.75 meters and its total length is 112.6 meters. In 2013, the bridge railings were refurbished to the original model, and in 2014,

90-461: A bronze statue of Trajan. Apollodorus used wooden arches, each spanning 38 m (125 ft), set on twenty masonry pillars made of bricks, mortar, and pozzolana cement. It was built unusually quickly (between 103 and 105), employing the construction of a wooden caisson for each pier. Apollodorus applied the technique of river flow relocation, using the principles set by Thales of Miletus some six centuries beforehand. Engineers waited for

135-512: A deck arch bridge. Any part supported from arch below may have spandrels that are closed or open. The Sydney Harbour Bridge and the Bayonne Bridge are a through arch bridge which uses a truss type arch. Also known as a bowstring arch, this type of arch bridge incorporates a tie between two opposite ends of the arch. The tie is usually the deck and is capable of withstanding the horizontal thrust forces which would normally be exerted on

180-524: A historical value, as the members of the Roman legions and cohorts which participated in the construction of the bridge carved the names of their units into the bricks. Thus, it is known that work was done by the legions of IV Flavia Felix , VII Claudia , V Macedonica and XIII Gemina and the cohorts of I Cretum, II Hispanorum, III Brittonum and I Antiochensium. A Roman memorial plaque (" Tabula Traiana "), 4 metres wide and 1.75 metres high, commemorating

225-609: A length of 167 feet (51 m) and span of 123 feet (37 m), is the world's first wholly stone open-spandrel segmental arch bridge, allowing a greater passage for flood waters. Bridges with perforated spandrels can be found worldwide, such as in China ( Zhaozhou Bridge , 7th century). Greece ( Bridge of Arta , 17th century) and Wales ( Cenarth Bridge , 18th century). In more modern times, stone and brick arches continued to be built by many civil engineers, including Thomas Telford , Isambard Kingdom Brunel and John Rennie . A key pioneer

270-518: A low water level to dig a canal, west of the modern downtown of Kladovo. The water was redirected 2 km (1.2 mi) downstream from the construction site, through the lowland of Ključ region  [ sr ] , to the location of the modern village of Mala Vrbica . Wooden pillars were driven into the river bed in a rectangular layout, which served as the foundation for the supporting piers , which were coated with clay. The hollow piers were filled with stones held together by mortar , while from

315-448: A quantity of fill material (typically compacted rubble) above the arch in order to increase this dead-weight on the bridge and prevent tension from occurring in the arch ring as loads move across the bridge. Other materials that were used to build this type of bridge were brick and unreinforced concrete. When masonry (cut stone) is used the angles of the faces are cut to minimize shear forces. Where random masonry (uncut and unprepared stones)

360-415: A result, masonry arch bridges are designed to be constantly under compression, so far as is possible. Each arch is constructed over a temporary falsework frame, known as a centring . In the first compression arch bridges, a keystone in the middle of the bridge bore the weight of the rest of the bridge. The more weight that was put onto the bridge, the stronger its structure became. Masonry arch bridges use

405-454: 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 countries (including former Yugoslavia ). Roman arch bridges were usually semicircular , although a number were segmental arch bridges (such as Alconétar Bridge ), a bridge which has a curved arch that

450-430: A three-hinged bridge has hinged in all three locations. Most modern arch bridges are made from reinforced concrete . This type of bridge is suitable where a temporary centring may be erected to support the forms, reinforcing steel, and uncured concrete. When the concrete is sufficiently set the forms and falseworks are then removed. It is also possible to construct a reinforced concrete arch from precast concrete , where

495-613: A triangular corbel arch. The 4th century BC Rhodes Footbridge rests on an early voussoir arch. Although true arches were already known by the Etruscans and ancient Greeks , the Romans were – as with the vault and the dome – 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 ,

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540-537: A vertical load on the arch supports. A viaduct (a long bridge) may be made from a series of arches, although other more economical structures are typically used today. Possibly the oldest existing arch bridge is the Mycenaean Arkadiko Bridge in Greece from about 1300 BC. The stone corbel arch bridge is still used by the local populace. The well-preserved Hellenistic Eleutherna Bridge has

585-428: Is a masonry, or stone, bridge where each successively higher course (layer) cantilevers slightly more than the previous course. The steps of the masonry may be trimmed to make the arch have a rounded shape. The corbel arch does not produce thrust, or outward pressure at the bottom of the arch, and is not considered a true arch . It is more stable than a true arch because it does not have this thrust. The disadvantage

630-452: 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

675-432: Is that this type of arch is not suitable for large spans. In some locations it is necessary to span a wide gap at a relatively high elevation, such as when a canal or water supply must span a valley. Rather than building extremely large arches, or very tall supporting columns (difficult using stone), a series of arched structures are built one atop another, with wider structures at the base. Roman civil engineers developed

720-402: Is used they are mortared together and the mortar is allowed to set before the falsework is removed. Traditional masonry arches are generally durable, and somewhat resistant to settlement or undermining. However, relative to modern alternatives, such bridges are very heavy, requiring extensive foundations . They are also expensive to build wherever labor costs are high. The corbel arch bridge

765-610: The Alcántara Bridge . The Romans also introduced segmental arch bridges into bridge construction. The 330 m-long (1,080 ft) Limyra Bridge in southwestern Turkey features 26 segmental arches with an average span-to-rise ratio of 5.3:1, giving the bridge an unusually flat profile unsurpassed for more than a millennium. Trajan's bridge over the Danube featured open- spandrel segmental arches made of wood (standing on 40 m-high (130 ft) concrete piers). This

810-683: 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

855-703: The Venetian Rialto bridge and the Fleischbrücke in Nuremberg (span-to-rise ratio 6.4:1) were founded on thousands of wooden piles, partly rammed obliquely into the grounds to counteract more effectively the lateral thrust. In China, the oldest existing arch bridge is the Zhaozhou Bridge of 605 AD, which combined a very low span-to-rise ratio of 5.2:1, with the use of spandrel arches (buttressed with iron brackets). The Zhaozhou Bridge, with

900-565: The 15th century, even featured a span length of 72 m (236 ft), not matched until 1796. Constructions such as the acclaimed Florentine segmental arch bridge Ponte Vecchio (1345) combined sound engineering (span-to-rise ratio of over 5.3 to 1) with aesthetical appeal. The three elegant arches of the Renaissance Ponte Santa Trinita (1569) constitute the oldest elliptic arch bridge worldwide. Such low rising structures required massive abutments , which at

945-621: The Danube safer for navigation enabling an effective river fleet, a string of defense posts and development of the intelligence service on the border. The remains of the embankment which protected the area during the construction of the canal (in a loop to the south of the Danube) show the magnitude of the works. The 3.2 km (2.0 mi) long canal bypassed the problematic section of the river in an arch-like style. Former canals eventually filled with sand, and empty shells are regularly found in

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990-436: The abutments of an arch bridge. The deck is suspended from the arch. The arch is in compression, in contrast to a suspension bridge where the catenary is in tension. A tied-arch bridge can also be a through arch bridge. An arch bridge with hinges incorporated to allow movement between structural elements. A single-hinged bridge has a hinge at the crown of the arch , a two-hinged bridge has hinges at both springing points and

1035-416: The arch and the deck is known as the spandrel . If the spandrel is solid, usually the case in a masonry or stone arch bridge, the bridge is called a closed-spandrel deck arch bridge . If the deck is supported by a number of vertical columns rising from the arch, the bridge is known as an open-spandrel deck arch bridge . The Alexander Hamilton Bridge is an example of an open-spandrel arch bridge. Finally, if

1080-400: The arch is built in two halves which are then leaned against each other. Many modern bridges, made of steel or reinforced concrete, often bear some of their load by tension within their structure. This reduces or eliminates the horizontal thrust against the abutments and allows their construction on weaker ground. Structurally and analytically they are not true arches but rather a beam with

1125-422: The arch supports the deck only at the top of the arch, the bridge is called a cathedral arch bridge . This type of bridge has an arch whose base is at or below the deck, but whose top rises above it, so the deck passes through the arch. The central part of the deck is supported by the arch via suspension cables or tie bars, as with a tied-arch bridge . The ends of the bridge may be supported from below, as with

1170-494: The bridge lamps were replaced with the original model. This article about a bridge in Finland is a stub . You can help Misplaced Pages by expanding it . Arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch . Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side, and partially into

1215-654: The bridge, occupying several hectares. Remnants of the 40 m (130 ft) long castrum with thick ramparts are still visible today. A vicus (civilian settlement) grew up around it later. A bronze head of Emperor Trajan has been discovered in Pontes, part of a statue which was erected at the bridge entrance and is today kept in the National Museum in Belgrade . On the north bank is the Drobeta fort. It also had

1260-527: The completion of Trajan's military road is located on the Serbian side facing Romania near Ogradina, 29 km west of the bridge. In 1972, when the Iron Gate I Hydroelectric Power Station was built (causing the water level to rise by about 35 m), the plaque was moved from its original location, and lifted to the present place. It reads: The text was interpreted by Otto Benndorf to mean: The Tabula Traiana

1305-414: The design and constructed highly refined structures using only simple materials, equipment, and mathematics. This type is still used in canal viaducts and roadways as it has a pleasing shape, particularly when spanning water, as the reflections of the arches form a visual impression of circles or ellipses. This type of bridge comprises an arch where the deck is completely above the arch. The area between

1350-503: The eccentric Puente del Diablo (1282). The 14th century in particular saw bridge building reaching new heights. Span lengths of 40 m (130 ft), previously unheard of in the history of masonry arch construction, were now reached in places as diverse as Spain ( Puente de San Martín ), Italy ( Castelvecchio Bridge ) and France ( Devil's bridge and Pont Grand ) and with arch types as different as semi-circular, pointed and segmental arches. The bridge at Trezzo sull'Adda , destroyed in

1395-536: The empire from barbarian invasions from the north. The superstructure was destroyed by fire. The remains of the bridge reappeared in 1858 when the level of the Danube hit a record low due to the extensive drought. The twenty pillars were still visible. In 1906, the Commission of the Danube decided to destroy two of the pillars that were obstructing navigation. In 1932, there were 16 pillars remaining underwater, but in 1982 only 12 were mapped by archaeologists;

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1440-484: The ground. All these works, especially the bridge, served the purpose of preparing for the Roman invasion of Dacia , which ended with Roman victory in 106 AD. The effect of finally defeating the Dacians and acquiring their gold mines was so great that Roman games celebrating the conquest lasted for 123 days, with 10,000 gladiators engaging in fights and 11,000 wild animals being killed during that period. The bridge

1485-409: The outside they were built around with Roman bricks . The bricks can still be found around the village of Kostol, retaining the same physical properties that they had 2 millennia ago. The piers were 44.46 m (145.9 ft) tall, 17.78 m (58.3 ft) wide and 50.38 m (165.3 ft) apart. It is considered today that the bridge construction was assembled on the land and then installed on

1530-409: The pillars. A mitigating circumstance was that the year the relocating canals were dug was very dry and the water level was quite low. The river bed was almost completely drained when the foundation of the pillars began. There were 20 pillars in total in an interval of 50 m (160 ft). Oak wood was used and the bridge was high enough to allow ship transport on the Danube. The bricks also have

1575-400: The plaque in several smaller pieces in order to be moved was abandoned due to the quality of the rock of which it was made. The proposition of lifting it with the floating elevator " Veli Jože " was discarded, too. The motion of cutting the table in one piece and placing it somewhere else was rejected as the plaque would lose its authenticity. In the end it was decided to dig in a new bed into

1620-517: The plaque to be preserved and the government accepted the motion. The enterprise entrusted with the task of relocation was the mining company " Venčac " as its experts previously participated in the relocation of the Abu Simbel temple in Egypt . First idea was to leave the plaque at its position and to build the caisson around it but the calculations showed this wouldn't work. The idea of cutting

1665-481: The rock 22 m (72 ft) above the plaque's original location. The plaque was then cut in one piece with the parts of the surrounding rock and road. After being cut with the cable saws, the 350 tons heavy chunk was lifted to the new bed. Works began in September 1967 and were finished in 1969. The wooden superstructure of the bridge was dismantled by Trajan's successor, Hadrian , presumably in order to protect

1710-455: The shape of an arch. See truss arch bridge for more on this type. A modern evolution of the arch bridge is the long-span through arch bridge . This has been made possible by the use of light materials that are strong in tension such as steel and prestressed concrete. "The Romans were the first builders in Europe, perhaps the first in the world, fully to appreciate the advantages of the arch,

1755-402: The vault and the dome." Trajan%27s bridge Trajan's Bridge ( Romanian : Podul lui Traian ; Serbian : Трајанов мост , romanized :  Trajanov most ), also called Bridge of Apollodorus over the Danube , was a Roman segmental arch bridge , the first bridge to be built over the lower Danube and considered one of the greatest achievements in Roman architecture . Though it

1800-402: Was Jean-Rodolphe Perronet , who used much narrower piers, revised calculation methods and exceptionally low span-to-rise ratios. Different materials, such as cast iron , steel and concrete have been increasingly used in the construction of arch bridges. Stone, brick and other such materials are strong in compression and somewhat so in shear , but cannot resist much force in tension . As

1845-474: Was 1,135 m (3,724 ft) long (the Danube is now 800 m (2,600 ft) wide in that area), 15 m (49 ft) wide, and 19 m (62 ft) high, measured from the surface of the river. At each end was a Roman fort so that crossing the bridge was only possible through the camps. On the south bank, at the modern village of Kostol near Kladovo, the Pontes fort was built in 103, concurrently with

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1890-481: Was declared a Monument of Culture of Exceptional Importance in 1979, and is protected by the Republic of Serbia . When the plan for the future hydro plant and its reservoir was made in 1965, it was clear that numerous settlements along the banks would be flooded in both Yugoslavia and Romania, and that historical remains, including the plaque, would also be affected. Serbian Academy of Sciences and Arts urged for

1935-487: Was only functional for 165 years, it is often considered to have been the longest arch bridge in both total span and length for more than 1,000 years. The bridge was completed in 105 AD and designed by Emperor Trajan 's architect Apollodorus of Damascus before the Second Dacian War to allow Roman troops to cross the river. Fragmentary ruins of the bridge's piers are still in existence. The bridge

1980-732: Was situated east of the Iron Gates , near the present-day cities of Drobeta-Turnu Severin in Romania and Kladovo in Serbia . Its construction was ordered by the Emperor Trajan as a supply route for the Roman legions fighting in Dacia . Construction of the bridge was part of a wider project, which included the digging of side canals so that whitewater rapids could be avoided to make

2025-661: Was to be the longest arch bridge for a thousand years both in terms of overall and individual span length, while the longest extant Roman bridge is the 790 m-long (2,590 ft) long Puente Romano at Mérida . The late Roman Karamagara Bridge in Cappadocia may represent the earliest surviving bridge featuring a pointed arch. In medieval Europe, bridge builders improved on the Roman structures by using narrower piers , thinner arch barrels and higher span-to-rise ratios on bridges. Gothic pointed arches were also introduced, reducing lateral thrust, and spans increased as with

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