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Three common types of bridge design. (credit: © Merriam-Webster Inc.)

Structure that spans horizontally to allow pedestrians and vehicles to cross a void. Bridge construction has always presented civil engineering with its greatest challenges. The simplest bridge is the beam (or girder) bridge, consisting of straight, rigid beams of steel or concrete placed across a span. Ancient Roman bridges are famous for their rounded arch form, which permitted spans much longer than those of stone beams and were more durable than wood. A modern version of the arch bridge might have a trussed arch anchored to the abutments and a deck hanging from the arch by vertical cables. Suspension bridges (e.g., Brooklyn Bridge, Golden Gate Bridge) are capable of spanning great distances; their main support members are cables composed of thousands of strands of wire supported by two towers and anchored at each end, and the deck is suspended by vertical cables hung from the main cables. In cable-stayed bridges, cables fan out and down from a central tower to various points on the deck; variations of this design have resulted in bridges of striking design and very long span. Other bridges include the truss bridge, popular (e.g., for railroad bridges) because it uses a relatively small amount of material to carry large loads, and the cantilever bridge, typically made with three spans, with the outer spans anchored down at the shore and the central span resting on the cantilevered arms.

For more information on bridge, visit Britannica.com.

A structure built to provide ready passage over natural or artificial obstacles, or under another passageway. Bridges serve highways, railways, canals, aqueducts, utility pipelines, and pedestrian walkways. In many jurisdictions, bridges are defined as those structures spanning an arbitrary minimum distance, generally about 10–20 ft (3–6 m); shorter structures are classified as culverts or tunnels. In addition, natural formations eroded into bridgelike form are often called bridges. This article covers only bridges providing conventional transportation passageways.

Bridges generally are considered to be composed of three separate parts: substructure, superstructure, and deck. The substructure or foundation of a bridge consists of the piers and abutments which carry the superimposed load of the superstructure to the underlying soil or rock. The superstructure is that portion of a bridge or trestle lying above the piers and abutments. The deck or flooring is supported on the bridge superstructure; it carries and is in direct contact with the traffic for which passage is provided.

Bridges are classified in several ways. Thus, according to the use they serve, they may be termed railway, highway, canal, aqueduct, utility pipeline, or pedestrian bridges. If they are classified by the materials of which they are constructed (principally the superstructure), they are called steel, concrete, timber, stone, or aluminum bridges. Deck bridges carry the deck on the very top of the superstructure. Through bridges carry the deck within the superstructure. The type of structural action is denoted by the application of terms such as truss, arch, suspension, stringer or girder, stayed-girder, composite construction, hybrid girder, continuous, cantilever, or orthotropic (steel deck plate).

The two most general classifications are the fixed and the movable. In the former, the horizontal and vertical alignment of the bridge are permanent; in the latter, either the horizontal or vertical alignment is such that it can be readily changed to permit the passage beneath the bridge of traffic. Movable bridges are sometimes called drawbridges in an anachronistic reference to an obsolete type of movable bridge spanning the moats of castles.

A singular type of bridge is the floating or pontoon bridge, which can be a movable bridge if it is designed so that a portion of it can be moved to permit the passage of water traffic.

The term trestle is used to describe a series of short spans supported by braced towers, and the term viaduct is used to describe a high structure of short spans, often of arch construction.

Fixed bridges

This type of construction is selected when the vertical clearance provided beneath the bridge exceeds the clearance required by the traffic it spans. For very short spans, construction may be a solid slab or a number of beams; for longer spans, the choice may be girders or trusses. Still longer spans may dictate the use of arch construction, and if the spans are even longer, stayed-girder bridges are used. Suspension bridges are used for the longest spans.

Beam bridges consist of a series of beams, usually of rolled steel, supporting the roadway directly on their top flanges. The beams are placed parallel to traffic and extend from abutment to abutment. Plate-girder bridges are used for longer spans than can be practically traversed with a beam bridge. In its simplest form, the plate girder consists of two flange plates welded to a web plate, the whole having the shape of an I. Box-girder bridges have steel girders fabricated by welding four plates into a box section. A conventional floor beam and stringer can be used on box-girder bridges, but the more economical arrangement is to widen the top flange plate of the box so that it serves as the deck. When this is done, the plate is stiffened to desired rigidity by closely spaced bar stiffeners or by corrugated or honeycomb-type plates. These stiffened decks, which double as the top flange of the box girders, are termed orthotropic. The wearing surface on such bridges is usually a relatively thin layer of asphalt.

Truss bridges, consisting of members vertically arranged in a triangular pattern, can be used when the crossing is too long to be spanned economically by simple plate girders. Where there is sufficient clearance underneath the bridge, the deck bridge is more economical than the through bridge because the trusses can be placed closer together, reducing the span of the floor beams.

The continuous bridge is a structure supported at three or more points and capable of resisting bending and shearing forces at all sections throughout its length. The bending forces in the center of the span are reduced by the bending forces acting oppositely at the piers. Trusses, plate girders, and box girders can be made continuous. The advantages of a continuous bridge over a simple-span bridge (that is, one that does not extend beyond its two supports) are economy of material, convenience of erection (without need for falsework), and increased rigidity under traffic. The disadvantages are its sensitivity to relative change in the levels of supporting piers, the difficulty of constructing the bridge to make it function as it is supposed to, and the occurrence of large movements at one location due to thermal changes.

The cantilever bridge consists of two spans projecting toward each other and joined at their ends by a suspended simple span. The projecting spans are known as cantilever arms, and these, plus the suspended span, constitute the main span. The cantilever arms also extend back to shore, and the section from shore to the piers offshore is termed the anchor span. Trusses, plate girders, and box girders can be built as cantilever bridges. The chief advantages of the cantilever design are the saving in material and ease of erection of the main span. The cable-stayed bridge, a modification of the cantilever bridge which has come into modern use, resembles a suspension bridge. It consists of girders or trusses cantilevering both ways from a central tower and supported by inclined cables attached to the tower at the top or sometimes at several levels.

The suspension bridge is a structure consisting of either a roadway or a truss suspended from two cables which pass over two towers and are anchored by backstays to a firm foundation. If the roadway is attached directly to the cables by suspenders, the structure lacks rigidity, with the result that wind loads and moving live loads distort the cables and produce a wave motion on the roadway. When the roadway is supported by a truss which is hung from the cable, the structure is called a stiffened suspension bridge. The stiffening truss distributes the concentrated live loads over a considerable length of the cable.

Since the development of the prestressing method, bridges of almost every type are being constructed of concrete. Prior to the advent of prestressing, these bridges were of three types: (1) arches, which were built in either short or long spans; (2) slab bridges of quite short spans, which were simply reinforced concrete slabs extending from abutment to abutment; and (3) deck girder bridges, consisting of concrete slabs built integrally with a series of concrete girders placed parallel to traffic. The advent of prestressed concrete greatly extended the utility and economy of concrete for bridges, particularly by making the hollow box-girder type practicable. See also Prestressed concrete.

Movable bridges

Modern movable bridges are either bascule, vertical lift, or swing; with few exceptions, they span waterways. They are said to be closed when set for the traffic they carry, and open when set to permit traffic to pass through the waterway they cross. Bascule and swing bridges provide unlimited vertical clearance in the open position. The vertical clearance of a lift bridge is limited by its design.

The bascule bridge consists primarily of a cantilever span, which may be either a truss or a plate girder, extending across the channel. Bascule bridges rotate about a horizontal axis parallel with the waterway. The portion of the bridge on the land side of the axis, carrying a counterweight to ease the mechanical effort of moving the bridge, drops downward, while the forward part of the leaf opens up over the channel much like the action of a playground seesaw. Bascule bridges may be either single-leaf, where rotation of the entire leaf over the waterway is about one axis on one side of the waterway, or double-leaf, where the leaves over the waterway rotate about two axes on opposite sides of the waterway.

The vertical-lift bridge has a span similar to that of a fixed bridge and is lifted by steel ropes running over large sheaves at the tops of its towers to the counterweights, which fall as the lift span rises and rise as it falls. If the bridge is operated by machinery on each tower, it is known as a tower drive. If it is driven by machinery located on the lift span, it is known as a span drive.

Swing bridges revolve about a vertical axis on a pier, called the pivot pier, in the waterway. There are three general classes of swing bridges: the rim-bearing, the center-bearing, and the combined rim-bearing and center-bearing. Rim-bearing bridges are supported on circular girder drums on rollers, center-bearing on a single large bearing at the center of rotation.

Substructure

Bridge substructure consists of those elements that support the trusses, girders, stringers, floor beams, and decks of the bridge superstructure. Piers and abutments are the primary bridge substructure elements. Other types of substructure, such as skewbacks for arch bridges, pile bents for trestles, and various forms of support wall, are also commonly used for specific applications.

Degradation

Many factors can cause bridges to degrade and become structurally deficient and in need of repair. Two environmental factors that cause significant damage to primarily concrete components in bridges are excessive changes in temperature and freeze-thaw cycles in the presence of moisture. Steel structures are vulnerable to corrosion, especially in prolonged moisture environments. Use of deicing salts on concrete pavements and bridge decks produces chemical reactions that accelerate the corrosion of reinforcing steel. A significant cause of bridge damage is vehicular impact and fatigue from repeated truck loads. Special loads, such as seismic, wind, and snow, also may produce dramatic degradation of bridge structures. See also Earthquake; Mechanical vibration.

Strengthening techniques

The strengthening of concrete bridges is generally achieved by replacing the damaged material, incorporating additional structural members, as in external prestressing, or increasing the size and capacity of existing members.

Repair techniques

Numerous repair techniques have evolved for concrete members in both bridges and buildings for replacing damaged concrete, repairing cracks, and repairing corroded reinforced steel bars. Steel bridges are most often strengthened by the addition of new steel members or smaller elements. Steel welding and bolting are well-developed techniques for steel connections. Thus, strengthening of steel bridges is perhaps more defined than for the concrete bridges. Techniques for repairing steel bridge elements include flame straightening, hot mechanical straightening, cold mechanical straightening, welding, bolting, partial replacement and complete replacement.

Definition: connect, extend
Antonyms: detach, disconnect, disjoin, disunite, unlink

v

Definition: span
Antonyms: divide, separate

1. A structure that spans a depression or provides a passage between two points which are at a height above the ground affording a passage for pedestrians, vehicles, etc.
2. At a demolition or construction site, a scaffold built over the adjacent sidewalk to protect pedestrians and motor vehicles from falling material or debris. 3. In the backstage of a theater, a platform or gallery (of fixed or adjustable height), over or alongside the stage; used by scene painters (see paint bridge), lighting operators (see light bridge), and stagehands.

Cúchulainn has to cross the Bridge of Leaps to reach the realm of Scáthach. It is high, narrow, and slippery as an eel's tail; anyone failing to cross it will fall to sea-monsters below. Cúchulainn does cross, and on a second crossing kills a hag who opposes him.

Bridges have been essential to America's growth, and countless types were devised to carry highways, railroads, and even canals. Location, materials, cost, traffic, and the ingenuity and creativity of bridge engineers all have influenced the evolution of American bridge technology.

The Colonies and the Early Republic

Large-span bridge building in North America began with the Charles River Bridge at Cambridge, Massachusetts, in 1662. Its pile and beam construction was not unlike that used for centuries in Europe. The design placed heavy timber beams across piles that were hand driven into the riverbed. Side members were then tied together by cross beams, and wood decking was attached to stringers running parallel to the sides. Spans built this way were limited by the length of available timber and the depth of the water.

A more versatile bridge form, the truss, first came into use in the United States during the late eighteenth century. Trusses composed of a series of triangles were assembled from short lengths of timber that, depending upon their location, resisted the forces of either compression or tension. Because of the way in which it was assembled, the truss bridge could be lengthened to span distances far greater than the simple pile and beam bridge. Structural integrity in these bridges came from a balance of the opposing forces inherent in their construction. Because these spans were not self-supporting during construction, however, they were built on false work or framing that was later removed. As with all bridges regardless of type, they had to be designed to support their own weight or dead load, as well as the moving weight or live load that passed over them.

During the first two decades of the nineteenth century, Theodore Burr of Connecticut was one of the best-known American bridge builders. His 1817 patent for a combination arch and truss design was widely used in covered bridges. He had erected some forty-five highway spans in New York, New Jersey, and Pennsylvania by the time of his death in 1822. The wooden walls and roofs that were typical of covered bridges were necessary to protect the truss's countless wooden joints from the ravages of the weather.

By far the most lasting bridges built in the eighteenth and early nineteenth centuries were those made of masonry, but masonry construction was expensive and a shortage of qualified masons in the early Republic limited the number that were constructed. Those bridges were most often built in the form of an arch and assembly proceeded on timber falsework, for these bridges were self-supporting only after the last stone was put in place. When America's first railroads began laying out their routes in the 1820s and 1830s, their bridges were apt to be of stone, since once erected such bridges required little attention and were highly durable. As the pace of railroad expansion quickened toward the mid-nineteenth century, however, the need for bridges burgeoned and permanency was abandoned for expediency. The prevailing attitude was that quickly assembled and even temporary timber bridges and trestles could be replaced at some later date with more lasting structures once a rail line was producing revenue. The railroads' need for quickly constructed spans spurred the development of the truss bridge, constructed primarily of wood, throughout the first half of the nineteenth century.

The Expanding Nation

Individual types of truss bridges can be identified by the way their members were assembled. A large number of designs were patented during the nineteenth century. Some trusses were of no practical value, while others were over-engineered or too expensive to build. Those popular during the nineteenth century did not necessarily find similar acceptance in the twentieth century. In time, the broad range of trusses was gradually reduced to a few basic types that proved to be the strongest and most economical to build. By the early twentieth century, the Pratt and Warren were the most commonly used trusses and into the 1920s the truss was the most common bridge type in America.

As the railroads used ever heavier and faster rolling stock, it was necessary to replace wooden bridges with heavier and sturdier construction. Beginning in the 1840s, cast and wrought iron were being substituted for wood members in some bridges and during the 1850s railroads began turning to bridges made entirely of iron. During the 1870s, steel production increased greatly and the price fell to levels that made it reasonable for use in bridges. By 1930, the expansion of American railroads was over and their influence on the structural development of bridges was at an end.

Two significant advances in bridge technology took place in the late 1860s and early 1870s with the construction of the long-span metal arch bridge across the Mississippi River at St. Louis. First, not only was this bridge the first major spanning of North America's largest river, but engineer James B. Eads specified the use of steel in the bridge's arch members. The three tubular arches rested on masonry piers built on wooden caissons sunk in the riverbed. Second, this was the initial use in the United States of the technique in which excavation work inside a caisson took place in an atmosphere of compressed air. Prior to that workers had labored under water or in areas where water was diverted in some way. Air pressure within the caisson equaled the force exerted by the river water outside and the shell did not flood as excavation work inside progressed down toward bedrock. This technology was crucial in the successful execution of all subsequent subaqueous foundation work.

Limitations imposed by location have forced bridge builders to be innovative. It would be impractical, if not impossible, to erect a bridge across wide, deep ravines if the bridge required the support of extensive false work during construction. As a result, a method evolved that avoided the use of staging. In October 1876, engineer Charles Shaler Smith embarked on the construction of the first modern cantilever railroad span to bridge the 1,200-foot-wide and 275-foot-deep valley of the Kentucky River. Smith refined a bridge-building technique little used outside of ancient China. Cantilever construction employed counter balancing forces so that completed segments supported ongoing work as it progressed inward toward the span's midpoint.

Although the suspension bridge was not new in 1842, its future form was forecast when Charles Ellet's Philadelphia wire suspension bridge was opened to highway traffic that year. Suspension bridges in which the roadway or deck was suspended from heavy wrought iron chains had been built for years. For the first time in a major American span, the deck was suspended from relatively lightweight wire cables. Ellet used a European cable-making technique in which cables were composed of a number of small-diameter parallel wires. The shape of each cable was maintained and its interior protected when the bundle's exterior was wrapped with additional wire. The scale of the bridges that followed increased tremendously, but the basic technology for cable making remained the same.

Civil engineer John A. Roebling was the preeminent suspension bridge designer of the nineteenth century. His career began with a suspension canal aqueduct at Pittsburgh in the 1840s, and each of his following projects reflected a growing skill and daring. His combined railroad and highway-carrying suspension bridge across the Niagara River gorge was completed in 1855. In it a suspended double-deck wooden truss carried the two roadbeds. Although other types of bridges would be built to carry highway and urban rail systems, this was the lone example of a suspension bridge constructed to carry both. The overall design and appearance of his Ohio River suspension bridge at Cincinnati in 1867 foretold of his plans for New York City's even larger and monumental Brooklyn Bridge of 1883. The extensive use of steel throughout the bridge, and especially for its cables, was a watershed in bridge technology.

The Early Twentieth Century

A number of large suspension bridges were built during the first half of the twentieth century. They were ideal for spanning the broad waterways that seemed to stand in the way of the growth of modern America. Neither their construction nor their final form posed an impediment to the nation's busy waterways. During the first four decades of the century, New York City was the focus of much of that construction. The city's boroughs were joined by the Williamsburg (1903), Manhattan (1909), Triborough (1936), and Bronx-Whitestone (1939) suspension bridges. However, none compared in size to the magnificent George Washington Bridge, completed in 1931. It was the first bridge linking Manhattan and New Jersey, and represented a remarkable leap forward in scale. Its 3,500-foot-longsuspended span was double the length of the next largest. The bridge's four massive suspension cables passed over towers soaring more than 600 feet high and its roadway was suspended 250 feet above the Hudson River. It was never truly completed, as the masonry facing called for on each of its steel towers was omitted because of the Great Depression.

The federal government responded to the depression by funding many massive public works projects. Partially as a form of unemployment relief, San Francisco undertook the construction of two great suspension bridges. They spanned greater distances than any previously built bridges. Strong Pacific Ocean currents and the depth of the water in San Francisco Bay made the construction of both the San Francisco–Oakland Bridge (1936) and the Golden Gate Bridge (1937) particularly challenging, and no part of the project required more technical expertise than building the subaqueous tower piers.

Triumphs in bridge building have been tempered by failures and perhaps no span has received more notoriety because of its collapse than did the Tacoma Narrows Suspension Bridge across Puget Sound in Washington State. Beginning in the late 1930s, its construction progressed uneventfully until the bridge was completed in July 1940. The valley in which the bridge was built was subject to strong winds and gusts that set the bridge in motion even while it was under construction. These wind-induced undulations increased in frequency as the bridge neared completion. So noticeable were the span's movements that they earned the bridge the sobriquet Galloping Gertie. Several months after its opening, the bridge was subjected to a period of intense high winds, during which it literally tore itself apart. The rising, falling, and twisting of the deck was so violent that it broke loose from its suspender cables and crashed into the sound. It was later determined that the failure resulted from the bridge being too flexible. The narrow deck and the shallow profile of the steel girders supporting the deck provided little resistance to aerodynamic action. The bridge's collapse prompted a reevaluation of suspension bridge design and resulted in a move away from flexible designs toward much stiffer and wind-resistant construction. A redesigned span across Puget Sound was completed in 1950.

Of the few suspension spans built in the United States after the middle of the twentieth century, one of the more remarkable was the Verrazano-Narrows Bridge, which opened in November 1964. The bridge, situated across the entrance to New York Harbor, connected Staten Island to Brooklyn. It was designed by engineer Othmar H. Ammann, who during his career designed a number of New York City's bridges, including the George Washington Bridge. While no new techniques were introduced in its construction, the bridge is remembered for it huge overall dimensions and the unprecedented size of its individual parts as well as the speed—five years—with which it was erected.

The Late Twentieth Century

Although the first cable stay bridges appeared in seventeenth-century Europe, this type of bridge emerged in a rationalized form only during the 1950s. Their con-figuration may vary in appearance and in the complexity of the tower or towers as well as in the symmetry and placement of the cables. The most recognizable spans are characterized by a single tower or mast and multiple diagonal cables that, if arranged in a single vertical plane, pass over the tower and are affixed at opposite points along the center line of the deck. Decks can be assembled in cantilever fashion from sections of pre-cast, pre-stressed concrete. They offer many of the advantages of suspension bridges, yet require neither the lengthy and costly process of cable spinning nor large cable anchorages. Their overall load-bearing capacity is less than the more complex suspension bridge. One of the most notable American examples is the Sunshine Skyway Bridge completed across Tampa Bay, Florida, in 1987.

With the expansion of American railroads nearing its end, highways became a major factor in bridge design and construction during the 1920s. As a result, the majority of spans constructed during the remainder of the twentieth century were relatively light, reinforced, and prestressed concrete highway bridges. Reinforced concrete bridge construction, in which steel imbedded in the concrete controls the forces of tension, was introduced in the United States in the late nineteenth century. Eventually, a variety of reinforcing systems were patented. The interstate highway system's rapid growth during the 1950s and 1960s fostered the widespread use of pre-stressed concrete beam bridges. Beams fabricated in this way were strengthened by built-in compressive forces. These bridges became the most common type of span in late-twentieth-century America.

Bibliography

Condit, Carl W. American Building Art: The Nineteenth Century. New York: Oxford University Press, 1960.

———. American Building Art: The Twentieth Century. New York: Oxford University Press, 1961.

Jackson, Donald C. Great American Bridges and Dams. Washington, D.C.: Preservation Press, 1988.

McCullough, David. The Great Bridge. New York: Simon and Schuster, 1972.

Petroski, Henry. Engineers of Dreams: Great Bridge Builders and the Spanning of America. New York: Knopf, 1995.

Scott, Quinta, and Howard S. Miller. The Eads Bridge. Columbia: University of Missouri Press, 1979.

Van der Zee, John. The Gate: The True Story of the Design and Construction of the Golden Gate Bridge. New York: Simon and Schuster, 1986.

Wittfoht, Hans. Building Bridges: History, Technology, Construction. Dusseldorf, Germany: Beton-Verlag, 1984.

—William E. Worthington Jr.

LearnThatWord.com is a free vocabulary and spelling program where you only pay for results!

Bridges often indicate literal travel. They also frequently represent life transitions. Because bodies of water symbolize the subconscious as well as the emotions, a bridge may indicate a structure that keeps one from falling into one's subconscious or into one's emotions (as in "bridge over troubled water"). Bridges are also links between two otherwise separated shores. Any one of these connotations might be indicated, and thus bridge images must be interpreted in the larger context of the dream.

• Head and Neck - bridge: bony portion of nose where it joins brow
• Procedures - bridge: dental cementation of immovable metal prosthesis as base for dentures in gap left by missing teeth
• Tools and Equipment - bridge: mounting base for dentures, either fixed or removable, inserted in gap in teeth
• Electricity and Electronics - bridge: network configuration in which no two elements are in series or parallel; two-branch instrument that measures unknown impedance by balancing ratio of voltages in each branch to a known ratio
• Parts of Ships, Sails, and Equipment - bridge: uppermost front cabin; platform for captain
• Ornamental and Structural Parts - bridge: elevated crossing between buildings
• Urban Structures and Phenomena - bridge: structure carrying roadway for vehicles and/or pedestrians over depression, obstacle, or body of water: arch, bascule, cantilever, draw, flyover, foot, lift, pontoon, suspension, swing, toll, truss
• Performance, Airplay, and the Recording Industry - bridge: segment of pop song that connects verses and chorus
• Accessories - bridge: thin, arched support over which strings are stretched at belly of stringed instrument
• Broadcast Journalism - bridge: transition within story, esp. use of stand-up or walk and talk to relate portion of report
• Hobbies - bridge: card game played by two sets of partners
• Card Games

This article is about the structure. For for the card game, see Bridge (card game). For for other uses, see Bridge (disambiguation).

The Akashi-Kaikyō Bridge in Japan, the world's longest suspension span.

The Si-o-se Pol bridge over Zayandeh River is the epitome of Safavid dynasty (1502–1722) bridge design. Esfahan, Iran

A bridge is a structure built to span physical obstacles such as a body of water, valley, or road, for the purpose of providing passage over the obstacle. Designs of bridges vary depending on the function of the bridge, the nature of the terrain where the bridge is constructed, the material used to make it and the funds available to build it.

Contents 1 Etymology 2 History 3 Types of bridges 3.1 Beam bridges 3.2 Cantilever bridges 3.3 Arch bridges 3.4 Tied arch bridges 3.5 Suspension bridges 3.6 Cable-stayed bridges 3.7 Movable bridges 3.8 Double-decked bridges 3.9 By use 3.10 By material 4 Structure 5 Efficiency 6 Other functions 7 Bridge failures 8 Bridge monitoring 9 Visual index 10 See also 11 References 12 External links

Etymology

The Oxford English Dictionary traces the origin of the word bridge to an Old English word brycg, of the same meaning, derived from the hypothetical Proto-Germanic root brugjō. There are cognates in other Germanic languages.

History

Bamboo bridge over the Serayu River in Java, Indonesia (ca. 1910-40)

The Arkadiko Bridge in Greece (13th century BC), one of the oldest arch bridges in existence

An English 18th century example of an arch bridge in the Palladian style, with shops on the span: Pulteney Bridge, Bath

Roman bridge of Córdoba, Spain, built in the 1st century BC.^[1]

A log bridge in the French Alps near Vallorcine.

A Han Dynasty (202 BC – 220 AD) Chinese miniature model of two residential towers joined by a bridge

One of the most famous historical bridges in the world: Ponte Vecchio

Lomonosov Bridge in St. Petersburg

Stone arch bridge in Shaharah, Yemen

Primitive suspension bridge over the River Astore

Continuous under-deck truss bridge: Kingston-Rhinecliff Bridge.

Through truss bridge with steel girders and wooden carriageway

"Metrobridge" Vorobyovy Gory (ru:Метромост) double-deck bridge in Moscow carries the Moscow Metro

Old Bridge in Mostar, Bosnia and Herzegovina

Mehmed Paša Sokolović Bridge in Višegrad, Bosnia and Herzegovina

Abetxuko Bridge Unique truss bridge concept in Vitoria, Spain

The first bridges were made by nature itself — as simple as a log fallen across a stream or stones in the river. The first bridges made by humans were probably spans of cut wooden logs or planks and eventually stones, using a simple support and crossbeam arrangement. Some early Americans used trees or bamboo poles to cross small caverns or wells to get from one place to another. A common form of lashing sticks, logs, and deciduous branches together involved the use of long reeds or other harvested fibers woven together to form a connective rope capable of binding and holding together the materials used in early bridges.

The Arkadiko Bridge is one of four Mycenaean corbel arch bridges part of a former network of roads, designed to accommodate chariots, between Tiryns to Epidauros in the Peloponnese, in Greece. Dating to the Greek Bronze Age (13th century BC), it is one of the oldest arch bridges still in existence and use. Several intact arched stone bridges from the Hellenistic era can be found in the Peloponnese in southern Greece^[2]

The greatest bridge builders of antiquity were the ancient Romans.^[3] The Romans built arch bridges and aqueducts that could stand in conditions that would damage or destroy earlier designs. Some stand today.^[4] An example is the Alcántara Bridge, built over the river Tagus, in Spain. The Romans also used cement, which reduced the variation of strength found in natural stone.^[5] One type of cement, called pozzolana, consisted of water, lime, sand, and volcanic rock. Brick and mortar bridges were built after the Roman era, as the technology for cement was lost then later rediscovered.

The Arthashastra of Kautilya mentions the construction of dams and bridges.^[6] A Mauryan bridge near Girnar was surveyed by James Princep.^[7] The bridge was swept away during a flood, and later repaired by Puspagupta, the chief architect of emperor Chandragupta I.^[7] The bridge also fell under the care of the Yavana Tushaspa, and the Satrap Rudra Daman.^[7] The use of stronger bridges using plaited bamboo and iron chain was visible in India by about the 4th century.^[8] A number of bridges, both for military and commercial purposes, were constructed by the Mughal administration in India.^[9]

Although large Chinese bridges of wooden construction existed at the time of the Warring States, the oldest surviving stone bridge in China is the Zhaozhou Bridge, built from 595 to 605 AD during the Sui Dynasty. This bridge is also historically significant as it is the world's oldest open-spandrel stone segmental arch bridge. European segmental arch bridges date back to at least the Alconétar Bridge (approximately 2nd century AD), while the enormous Roman era Trajan's Bridge (105 AD) featured open-spandrel segmental arches in wooden construction.

Rope bridges, a simple type of suspension bridge, were used by the Inca civilization in the Andes mountains of South America, just prior to European colonization in the 16th century.

During the 18th century there were many innovations in the design of timber bridges by Hans Ulrich, Johannes Grubenmann, and others. The first book on bridge engineering was written by Hubert Gautier in 1716. A major breakthrough in bridge technology came with the erection of the Iron Bridge in Coalbrookdale, England in 1779. It used cast iron for the first time as arches to cross the river Severn.

With the Industrial Revolution in the 19th century, truss systems of wrought iron were developed for larger bridges, but iron did not have the tensile strength to support large loads. With the advent of steel, which has a high tensile strength, much larger bridges were built, many using the ideas of Gustave Eiffel.

In 1927 welding pioneer Stefan Bryła designed the first welded road bridge in the world, which was later built across the river Słudwia Maurzyce near Łowicz, Poland in 1929. In 1995, the American Welding Society presented the Historic Welded Structure Award for the bridge to Poland.^[10]

Types of bridges

There are six main types of bridges: beam bridges, cantilever bridges, arch bridges, suspension bridges, cable-stayed bridges and truss bridges.

Beam bridges

Beam bridges are horizontal beams supported at each end by abutments, hence their structural name of simply supported. When there is more than one span the intermediate supports are known as piers. The earliest beam bridges were simple logs that sat across streams and similar simple structures. In modern times, beam bridges are large box steel girder bridges. Weight on top of the beam pushes straight down on the abutments at either end of the bridge.^[11] They are made up mostly of wood or metal. Beam bridge spans typically do not exceed 250 feet (76 m) long, as the strength of a span decreases with increased length. However, the main span of the Rio-Niteroi Bridge, a box girder bridge, is 300 metres (980 ft). The world's longest beam bridge is Lake Pontchartrain Causeway in southern Louisiana in the United States, at 23.83 miles (38.35 km), with individual spans of 56 feet (17 m).^[12]

Cantilever bridges

Cantilever bridges are built using cantilevers—horizontal beams supported on only one end. Most cantilever bridges use a pair of continuous spans that extend from opposite sides of the supporting piers to meet at the center of the obstacle the bridge crosses. Cantilever bridges are constructed using much the same materials & techniques as beam bridges. The difference comes in the action of the forces through the bridge. The largest cantilever bridge is the 549-metre (1,801 ft) Quebec Bridge in Quebec, Canada.

Arch bridges

Arch bridges have abutments at each end. The weight of the bridge is thrust into the abutments at either side. The earliest known arch bridges were built by the Greeks, and include the Arkadiko Bridge.

With the span of 220 metres (720 ft), the Solkan Bridge over the Soča River at Solkan in Slovenia is the second largest stone bridge in the world and the longest railroad stone bridge. It was completed in 1905. Its arch, which was constructed from over 5,000 tonnes (4,900 long tons; 5,500 short tons) of stone blocks in just 18 days, is the second largest stone arch in the world, surpassed only by the Friedensbrücke (Syratalviadukt) in Plauen, and the largest railroad stone arch. The arch of the Friedensbrücke, which was built in the same year, has the span of 90 m (300 ft) and crosses the valley of the Syrabach River. The difference between the two is that the Solkan Bridge was built from stone blocks, whereas the Friedensbrücke was built from a mixture of crushed stone and cement mortar.^[13]

Dubai in the United Arab Emirates is currently building the Sheikh Rashid bin Saeed Crossing, which is scheduled for completion in 2012. When completed, it will be the largest arch bridge in the world, with a main span 667 metres (2,188 ft) long.^[14]

Tied arch bridges

Tied arch bridges have an arch-shaped superstructure, but differ from conventional arch bridges. Instead of transferring the weight of the bridge and traffic loads into thrust forces into the abutments, the ends of the arches are restrained by tension in the bottom chord of the structure. They are also called bowstring arches.

Suspension bridges

Suspension bridges are suspended from cables. The earliest suspension bridges were made of ropes or vines covered with pieces of bamboo. In modern bridges, the cables hang from towers that are attached to caissons or cofferdams. The caissons or cofferdams are implanted deep into the floor of a lake or river. The longest suspension bridge in the world is the 12,826 feet (3,909 m) Akashi Kaikyo Bridge in Japan.^[15] See simple suspension bridge, stressed ribbon bridge, underspanned suspension bridge, suspended-deck suspension bridge, and self-anchored suspension bridge.

Cable-stayed bridges

Cable-stayed bridges, like suspension bridges, are held up by cables. However, in a cable-stayed bridge, less cable is required and the towers holding the cables are proportionately shorter.^[16] The first known cable-stayed bridge was designed in 1784 by C.T. Loescher.^[17] The longest cable-stayed bridge is the Sutong Bridge over the Yangtze River in China.

Movable bridges

Movable bridges are designed to move out of the way of boats or other kinds of traffic, which would otherwise be too tall to fit. These are generally electrically powered.

Double-decked bridges

Double-decked or double-decker bridges have two levels, such as the San Francisco – Oakland Bay Bridge, with two road levels. Tsing Ma Bridge and Kap Shui Mun Bridge in Hong Kong have six lanes on their upper decks, and on their lower decks there are two lanes and a pair of tracks for MTR metro trains. Some double-decker bridges only use one level for street traffic; the Washington Avenue Bridge in Minneapolis reserves its lower level for automobile traffic and its upper level for pedestrian and bicycle traffic (predominantly students at the University of Minnesota). Likewise, in Toronto, the Prince Edward Viaduct has five lanes of motor traffic, bicycle lanes, and sidewalks on its upper deck; and a pair of tracks for the Bloor–Danforth subway line on its lower deck.

Robert Stephenson's High Level Bridge across the River Tyne in Newcastle upon Tyne, completed in 1849, is an early example of a double-deck bridge. The upper level carries a railway, and the lower level is used for road traffic. Other examples include Britannia Bridge over the Menai Strait and Craigavon Bridge in Derry, Northern Ireland. The Oresund Bridge between Copenhagen and Malmö consists of a four-lane highway on the upper level and a pair of railway tracks at the lower level. The George Washington Bridge between New Jersey and New York has two roadway levels. It was built with only the upper roadway as traffic demands did not require more capacity. A truss work between the roadway levels provides stiffness to the roadways and reduced movement of the upper level when installed. Tower Bridge is different example of a double-decker bridge, with the central section consisting of a low level bascule span and a high level footbridge. The George Washington bridge is also the most used bridge in the world.

Old Yamuna Bridge (Delhi) or Bridge No. 249 in technical railway parlance, was constructed in 1866 by the East India Railway at a cost of £16,16,335. It was built with a total length of 2,640 feet (800 m) and consisted of 12 spans of 202.5 feet (61.7 m) each. With the completion of this bridge, two principal cities of North India, Kolkata and Delhi, were connected by the railways; this being the last link of the trunk line on this route. In 1913, this was converted into a double line by adding down line girders of 12 spans of 202 feet (62 m) each and 2 end spans of 42 feet (13 m) to the bridge. For the movement of road traffic, two road bridges were provided below the lines. The entry of trains into Delhi Junction Railway station, in such close proximity to the Red Fort, never ceases to impress the rail traveler,^{[citation needed]} reminding all that after the Uprising of 1857, Delhi was a fortified city. The old Yamuna Bridge has an identical twin, a bridge further downstream at Naini on the Allahabad — Mughalsarai section of the now North Central Railways.

By use

A bridge is designed for trains, pedestrian or road traffic, a pipeline or waterway for water transport or barge traffic. An aqueduct is a bridge that carries water, resembling a viaduct, which is a bridge that connects points of equal height. A road-rail bridge carries both road and rail traffic.

Bridges are subject to unplanned uses as well. The areas underneath some bridges have become makeshift shelters and homes to homeless people, and the undersides of bridges all around the world are spots of prevalent graffiti. Some bridges attract people attempting suicide, and become known as suicide bridges.

To create a beautiful image, some bridges are built much taller than necessary. This type, often found in east-Asian style gardens, is called a Moon bridge, evoking a rising full moon. Other garden bridges may cross only a dry bed of stream washed pebbles, intended only to convey an impression of a stream. Often in palaces a bridge will be built over an artificial waterway as symbolic of a passage to an important place or state of mind. A set of five bridges cross a sinuous waterway in an important courtyard of the Forbidden City in Beijing, China. The central bridge was reserved exclusively for the use of the Emperor, Empress, and their attendants.

By material

Until the end of the 18th Century, bridges were made out of timber, stone and masonry. Modern bridge are currently built in concrete, steel, fiber reinforced polymers (FRP), stainless steel or combinations of those materials. The Iron Bridge completed in 1779 was the first cast iron bridge.

Structure

Bridges may be classified by how the forces of tension, compression, bending, torsion and shear are distributed through their structure. Most bridges will employ all of the principal forces to some degree, but only a few will predominate. The separation of forces may be quite clear. In a suspension or cable-stayed span, the elements in tension are distinct in shape and placement. In other cases the forces may be distributed among a large number of members, as in a truss, or not clearly discernible to a casual observer as in a box beam. Bridges can also be classified by their lineage, which is shown as the vertical axis on the diagram.^{[clarification needed]}

Efficiency

A bridge's structural efficiency is the ratio of load carried to bridge mass, given a specific set of material types. In one common challenge students are divided into groups and given a quantity of wood sticks, a distance to span, and glue, and then asked to construct a bridge that will be tested to destruction by the progressive addition of load at the center of the span. The bridge taking the greatest load is by this test the most structurally efficient. A more refined measure for this exercise is to weigh the completed bridge rather than measure against a fixed quantity of materials provided and determine the multiple of this weight that the bridge can carry, a test that emphasizes economy of materials and efficient glue joints (see balsa wood bridge).

A bridge's economic efficiency will be site and traffic dependent, the ratio of savings by having a bridge (instead of, for example, a ferry, or a longer road route) compared to its cost. The lifetime cost is composed of materials, labor, machinery, engineering, cost of money, insurance, maintenance, refurbishment, and ultimately, demolition and associated disposal, recycling, and replacement, less the value of scrap and reuse of components. Bridges employing only compression are relatively inefficient structurally, but may be highly cost efficient where suitable materials are available near the site and the cost of labor is low. For medium spans, trusses or box beams are usually most economical, while in some cases, the appearance of the bridge may be more important than its cost efficiency. The longest spans usually require suspension bridges.

Juscelino Kubitschek bridge in Brasília, Brazil

Other functions

Some bridges accommodate other purposes, such as the tower of Nový Most Bridge in Bratislava, which features a restaurant. Other suspension bridge towers carry transmission antennas.

A bridge can carry overhead power lines as does the Storstrøm Bridge.

Costs and cost overruns frequently occur in bridge construction. Flyvbjerg et al. (2003) found the average cost overrun in bridge building is 34%.^[18]

In railway parlance, an overbridge is a bridge crossing over the course of the railway. In contrast, an underbridge allows passage under the line.

Bridge failures

See also: List of bridge failures

The failure of bridges is of special concern for structural engineers in trying to learn lessons vital to bridge design, construction and maintenance. The failure of bridges first assumed national interest during the Victorian era when many new designs were being built, often using new materials.

In the United States, the National Bridge Inventory tracks the structural evaluations of all bridges, including designations such as "structurally deficient" and "functionally obsolete".

Bridge monitoring

See also: Structural Health Monitoring

There are several methods used to monitor the stress on large structures like bridges. The most common method is the use of an accelerometer, which is integrated into the bridge while it is being built. This technology is used for long-term surveillance of the bridge.^[19]

Another option for structural-integrity monitoring is "non-contact monitoring", which uses the Doppler effect (Doppler shift). A laser beam from a Laser Doppler Vibrometer is directed at the point of interest, and the vibration amplitude and frequency are extracted from the Doppler shift of the laser beam frequency due to the motion of the surface.^[20] The advantage of this method is that the setup time for the equipment is faster and, unlike an accelerometer, this makes measurements possible on multiple structures in as short a time as possible. Additionally, this method can measure specific points on a bridge that might be difficult to access.

Visual index

See list of bridge types

See also

• Architectural structure
• Bridge to Nowhere (disambiguation)
• BS 5400, a British Standard for steel, concrete and composite bridges
• Cost overrun in bridge construction
• Footbridge
• Landscape architecture
• Megaproject
• Overpass
• Oxford BT Centre for Major Programme Management
• Sea bridge
• Tunnel
• Transporter bridge

References

Notes

1. ^ "Roman Bridge in Cordoba ( 1st century B.C.)" (in (German)). En.structurae.de. http://en.structurae.de/structures/data/index.cfm?id=s0001269. Retrieved 2012-01-04. 
2. ^ T.H. Nielsen and J. Roy. Defining ancient Arkadia: symposium April 1–4, 1998. Kgl. Danske Videnskabernes Selska, 1998. p. 253. [1]
3. ^ "Context for World Heritage Bridges". Icomos.org. 1941-07-01. http://www.icomos.org/studies/bridges.htm. Retrieved 2012-01-04. 
4. ^ "History of BRIDGES". Historyworld.net. http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ab97. Retrieved 2012-01-04. 
5. ^ "Lessons from Roman Cement and Concrete". Pubs.asce.org. http://www.pubs.asce.org/WWWdisplay.cgi?0103045. Retrieved 2012-01-04. 
6. ^ Dikshitar, pg. 332
7. ^ ^{a b c} Dutt, pg 46
8. ^ "suspension bridge" in Encyclopædia Britannica (2008). 2008 Encyclopædia Britannica, Inc.
9. ^ Nath, pg. 213
10. ^ Sapp, Mark E. (February 22, 2008). "Welding Timeline 1900-1950". WeldingHistory.org. http://www.weldinghistory.org/whistoryfolder/welding/wh_1900-1950.html. Retrieved 2008-04-29. 
11. ^ "Beam bridges". Design Technology. http://www.design-technology.org/beambridges.htm. Retrieved 2008-05-14. 
12. ^ "A big prefabricated bridge". Life 40 (22): 53–60. 28 May 1956. 
13. ^ Gorazd Humar (September 2001). "World Famous Arch Bridges in Slovenia". In Charles Abdunur (in English, French). Arch'01: troisième Conférence internationale sur les ponts en arc Paris:. Paris: Presses des Ponts. pp. 121-124. ISBN 2-85978-347-4. http://books.google.com/books?id=E7ywmb24EQMC&lpg=PA121&dq=%22world%20famous%20arch%20bridges%20in%20slovenia%22&pg=PA121#v=onepage&q=%22world%20famous%20arch%20bridges%20in%20slovenia%22&f=false. 
14. ^ Glass, Amy. "Dubai to build world's longest arch bridge". Arabian Business. http://www.arabianbusiness.com/509621-worlds-longest-arch-bridge-for-dubai?ln=en. Retrieved 2008-05-14. 
15. ^ Sigmund, Pete (2007-02-07). "The Mighty Mac: A Sublime Engineering Feat". Construction Equipment Guide. http://www.constructionequipmentguide.com/story.asp?story=8153&headline=The%20Mighty%20Mac:%20A%20Sublime%20Engineering%20Feat. Retrieved 2008-05-14. 
16. ^ Johnson, Andy. "Cable Stay vs Suspension Bridges". U.S. Department of Energy. http://www.newton.dep.anl.gov/askasci/eng99/eng99373.htm. 
17. ^ "Bridges". NYCDOT. http://www.nyc.gov/html/dot/html/bridges/bridges.shtml. Retrieved 2008-05-14. 
18. ^ Flyvbjerg, Bent, Nils Bruzelius, and Werner Rothengatter, 2003. ''Megaprojects and Risk: An Anatomy of Ambition'' (Cambridge: Cambridge University Press). Books.google.com. http://books.google.com/books?vid=ISBN0521009464&id=RAV5P-50UjEC&printsec=frontcover&dq=megaprojects+and+Risk:+An+Anatomy+of+Ambition. Retrieved 2012-01-04. 
19. ^ "The new Minnesota smart bridge". http://www.mnme.com/pdf/smartbridge.pdf. Retrieved 2012-01-30. 
20. ^ "Basic Principles of Vibrometry". http://www.polytec.com/us/solutions/vibration-measurement/basic-principles-of-vibrometry/. Retrieved 2012-01-25. 

Bibliography

• Brown, David J. Bridges: Three Thousand Years of Defying Nature. Richmond Hill, Ont: Firefly Books, 2005. ISBN 1-55407-099-6.
• Sandak, Cass R. Bridges. An Easy-read modern wonders book. New York: F. Watts, 1983. ISBN 0-531-04624-9.
• Whitney, Charles S. Bridges of the World: Their Design and Construction. Mineola, NY: Dover Publications, 2003. ISBN 0-486-42995-4 (Unabridged republication of Bridges : a study in their art, science, and evolution. 1929.)
• Dikshitar, V. R. R. Dikshitar (1993). The Mauryan Polity. Motilal Banarsidass. ISBN 81-208-1023-6.
• Dutt, Romesh Chunder (2000). A History of Civilisation in Ancient India: Vol II. Routledge. ISBN 0-415-23188-4.
• Nath, R. (1982). History of Mughal Architecture. Abhinav Publications. ISBN 81-7017-159-8.
• Kinney, A. R.; el al. (2003). Worshiping Siva and Buddha: The Temple Art of East Java. University of Hawaii Press. ISBN 0-8248-2779-1.
• Buck, William; el al. (2000). Ramayana. University of California Press. ISBN 0-520-22703-4

External links

Wikisource has the text of the 1911 Encyclopædia Britannica article Bridges.

Find more about Bridge on Wikipedia's sister projects:
	Definitions and translations from Wiktionary
	Images and media from Commons
	Learning resources from Wikiversity
	News stories from Wikinews
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	Source texts from Wikisource
	Textbooks from Wikibooks

• Digital Bridge: Bridges of the Nineteenth Century, a collection of digitized books at Lehigh University
• Structurae - International Database and Gallery of Engineerings Structures with over 10000 Bridges.
• U.S. Federal Highway Administration Bridge Technology
• Bridge enthusiast site
• Video on how bridges are made (Grade school level educational film by National Association of Manufactures.)
• The Museum of Japanese Timber Bridges Fukuoka University
• "en.Broer.no": site for bridges
• [2] (CNN) 24 of the World's Most Amazing Bridges -retrieved 30 Apr 2011
• Amazing footage of strangler figs made into "living bridges." [3]

v t e Bridge-related articles Types of bridges Moveable bridge Beam bridge Burr Truss Cantilever bridge Arch bridge Suspension bridge Timber bridge Cable-stayed bridge Truss bridge Visual index to various types Lists of bridges List of bridges By length Longest suspension bridge spans Largest cable-stayed bridges Longest cantilever bridges Longest continuous truss bridges Arch bridges Highest Tallest Bridge failures

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Dansk (Danish)
1.
n. - bridge, fast forbindelse
v. tr. - bygge bro over, slå bro over

idioms:

• bridge roll    blød bolle
• bridging loan    mellemfinancieringslån

2.
n. - kommandobro

Nederlands (Dutch)
brug, overbrugging, rug van neus, bok (biljart), bestuurderscabine, bridge (kaartspel), kroon (op kies), overbruggen, bridgen

Français (French)
1.
n. - pont, (Naut) passerelle, arête (du nez), arcade (des lunettes), chevalet (d'un violon), (Dent) bridge
v. tr. - construire un pont, (fig) combler (un budget)

idioms:

• bridge roll    petit pain brioché
• bridging loan    (GB, Fin) prêt-relais

2.
n. - bridge (cartes)

Deutsch (German)
1.
n. - Brücke, Steg
v. - überbrücken, eine Brücke schlagen

idioms:

• bridge roll    kleines, weiches Brötchen
• bridging loan    (econ.) Überbrückungskredit

2.
n. - Bridge (Kartenspiel)

Ελληνική (Greek)
n. - γέφυρα, ράχη μύτης, (είδος χαρτοπαίγνιου) μπριτζ, (ναυτ.) γέφυρα (πλοίου), (μουσ.) καβαλάρης
v. - γεφυρώνω, συνδέω με γέφυρα

idioms:

• bridge roll    φραντζολάκι (ζυμωμένο με γάλα)
• bridging loan    προσωρινό διευκολυντικό δάνειο

Italiano (Italian)
bridge, ponte, ponte di comando, plancia

idioms:

• bridge roll    panino
• bridging loan    prefinanziamento
• build bridges    costruire ponti
• cross that bridge when one comes to it    non mettere il carro davanti ai buoi

Português (Portuguese)
n. - ponte (f), jogo (m) de cartas, ponte (f) de comando (Náut.), bridge (m)
v. - construir ponte sobre

idioms:

• bridge roll    pão macio e fino enrolado
• bridging loan    empréstimo (m) bancário
• build bridges    estabelecer conexão ou relação amigável
• cross that bridge when one comes to it    preocupar-se desnecessariamente
• suspension bridge    ponte (f) pênsil

Русский (Russian)
бридж, мост, капитанский мостик

idioms:

• bridge roll    мягкая булочка
• bridging loan    отсроченный кредит
• build bridges    устанавливать отношения
• cross that bridge when one comes to it    нечего заранее беспокоиться
• suspension bridge    висячий мост

Español (Spanish)
1.
n. - puente, pasarela, caballete, puente de mando
v. tr. - tender un puente, conectar en paralelo, salvar

idioms:

• bridge roll    panecillo
• bridging loan    préstamo de empalme, crédito puente

2.
n. - juego de bridge

Svenska (Swedish)
n. - bridge (spel), bro, brygga
v. - slå en bro över, överbrygga

中文（简体）(Chinese (Simplified))
1. 桥, 桥梁, 舰桥, 桥楼, 驾驶台, 架桥于, 使渡过, 把...连结起来

idioms:

• bridge roll    松软的小面包卷
• bridging loan    临时贷款

2. 桥牌

中文（繁體）(Chinese (Traditional))
1.
n. - 橋牌

2.
n. - 橋, 橋梁, 艦橋, 橋樓, 駕駛台
v. tr. - 架橋於, 使渡過, 把...連結起來

idioms:

• bridge roll    鬆軟的小麵包卷
• bridging loan    臨時貸款

한국어 (Korean)
1.
n. - 다리, 연락, 비계
v. tr. - ~에 다리를 놓다, 가교 역할을 하다

2.
n. - 브리지(카드 놀이의 일종)

日本語 (Japanese)
n. - 橋, 船橋, 鼻柱, 橋に似たもの
v. - 橋を架ける, 橋渡しをする, 切り抜ける

idioms:

• bridge roll    小型のロールパン

العربيه (Arabic)
‏(الاسم) جسر, برج القيادة في سفينه, لعبه ورق (فعل) أقام جسرا, سد النقص أو الثغرة‏

עברית (Hebrew)
n. - ‮גשר, גשרה, גשרית, החלק העליון של האף‬
v. tr. - ‮בנה גשר מעל-, נמתח מעל‬
n. - ‮ברידג' (משחק)‬

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