A hinged arch bridge is one with hinges incorporated into its structure to allow movement. In structural engineering, a hinge is essentially a "cut in the structure" that can withstand compressive forces. In a steel arch the hinge allows free rotation, [2] somewhat resembling a common hinge. The most common hinged arch bridge varieties are the two-hinged bridge with hinges at the springing points and the three-hinged bridge with an additional hinge at the crown of the arch; though single-hinged versions exist with a hinge only at the crown of the arch. Hinges at the springing point prevent bending moments from being transferred to the bridge abutments. A triple-hinged bridge is statically determinate, while the other versions are not.
A fixed arch bridge, that is one without hinges, exerts a bending moment at the abutments and stresses caused by change of temperature or shrinkage of concrete have to be taken up by the arch. A two-hinged arch has a hinge at the base of each arch (the springing point), while a three-hinged arch has a third hinge at the crown of the arch. [3] The advantage of the fixed arches is in their lower construction and maintenance costs. [2]
In a two-hinged arch bridge no bending moments are transferred to the abutments, due to the presence of the hinge. A change in the relative position of the abutments may cause a change in the thrust load exerted by the arch on the abutments. The addition of a third hinge at the crown, which allows rotation of the arch members, means that the thrust and shear forces exerted on the abutments are not affected by small movements in either abutment. Three-hinged arch bridges are, therefore, used when there is the possibility of unequal settlement of the abutments. [3] Single-hinged arch bridges, with a hinge only at the crown, were also built though in relatively small numbers compared to the other types. [4]
A three hinged bridge is isostatic, that is it is statically determinate; a two-hinged bridge is statically indeterminate in one degree of freedom, while a fixed arch bridge is indeterminate in three degrees of freedom. [5] [6] The statically determinate three-hinged arches were popular until the Second World War. Post-war, the advances in calculation methods allowed broad use of statically indeterminate schemes. In the end of the 20th century three-hinged arches made a comeback associated with the uses of engineered wood ("glulam") in bridge construction: [7] the glulam construction have to be pre-fabricated, using three-hinged design naturally divides the arch into two halves that are easier to transport. [8]
While in steel arches hinges typically allow free rotation of connected parts, in reinforced concrete bridges typical implementation of a hinge involves thinning of the concrete structure while adding more reinforcement locally. [2]
Early arch bridges were fixed arches. The two-hinged bridge was developed by the engineers Couche and Salle in 1858 for a wrought iron bridge carrying the Paris-Creil railway line across the Canal Saint-Denis. They had attempted to introduce a third hinge at the crown but were unsuccessful because the thickness of the arch was insufficient. [9] The first three-hinged bridge was the Unterspree Bridge in Berlin (Johann Wilhelm Schwedler, 1863), built two years after the pioneering theoretical work by Claus Koepcke . [2] Hradecky Bridge (1866) is probably the oldest three-hinged bridge still used. [10]
Hinged bridges were popular with railway companies, who often had the need to construct large bridges. The Arch Bridge at Bellows Falls in New England, built in 1905, is a particularly large example of a three-hinged arch bridge. At 540 feet (160 m) in length it was the longest in America when built. [4] The 1888 Hennepin Avenue Bridge in Minneapolis was unusual in that it was both a two- and three-hinged bridge. The bridge was split longitudinally with the two halves being built by different companies. The north arch ribs are three-hinged, while the south arch ribs are two-hinged. [11] Three-hinged arch bridges remain popular in modern civil engineering. [12]
An arch is a curved vertical structure spanning an open space underneath it. Arches may support the load above them, or they may perform a purely decorative role. As a decorative element, the arch dates back to the 4th millennium BC, but structural load-bearing arches became popular only after their adoption by the Ancient Romans in the 4th century BC.
The ancient Romans were the first civilization to build large, permanent bridges. Early Roman bridges used techniques introduced by Etruscan immigrants, but the Romans improved those skills, developing and enhancing methods such as arches and keystones. There were three major types of Roman bridge: wooden, pontoon, and stone. Early Roman bridges were wooden, but by the 2nd century BC stone was being used. Stone bridges used the arch as their basic structure, and most used concrete, the first use of this material in bridge-building.
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 a vertical load on the arch supports. A viaduct may be made from a series of arches, although other more economical structures are typically used today.
A truss is an assembly of members such as beams, connected by nodes, that creates a rigid structure.
The Galton Bridge is a cast-iron bridge in Smethwick, near Birmingham, in the West Midlands of England. Opened in 1829 as a road bridge, the structure has been pedestrianised since the 1970s. It was built by Thomas Telford to carry a road across the new main line of the Birmingham Canal, which was built in a deep cutting. The bridge is 70 feet above the canal, making it reputedly the highest single-span arch bridge in the world when it was built, 26 feet wide, and 150 feet long. The iron components were fabricated at the nearby Horseley Ironworks and assembled atop the masonry abutments. The design includes decorative lamp-posts and X-shaped bracing in the spandrels.
A cantilever bridge is a bridge built using structures that project horizontally into space, supported on only one end. For small footbridges, the cantilevers may be simple beams; however, large cantilever bridges designed to handle road or rail traffic use trusses built from structural steel, or box girders built from prestressed concrete.
Several members of the Swiss family Grubenmann were famous as carpenters and civil engineers in the 18th century. The sons were innovators in bridge construction.
Glued laminated timber, commonly referred to as glulam, is a type of structural engineered wood product constituted by layers of dimensional lumber bonded together with durable, moisture-resistant structural adhesives so that all of the grain runs parallel to the longitudinal axis. In North America, the material providing the laminations is termed laminating stock or lamstock.
A vertical-lift bridge or just lift bridge is a type of movable bridge in which a span rises vertically while remaining parallel with the deck.
The Landwasser Viaduct is a single-track six-arched curved limestone railway viaduct. It spans the Landwasser between Schmitten and Filisur, in the canton of Graubünden, Switzerland.
A stressed ribbon bridge is a tension structure similar in many ways to a simple suspension bridge. The suspension cables are embedded in the deck, which follows a catenary arc between supports. As with a simple suspension bridge, the weight is taken by the suspension cables, but unlike the simple span, the deck or ribbon is stressed in compression, which adds to the stiffness of the structure. The supports in turn sustain upward-thrusting arcs that allow the grade to be changed between spans. Such bridges are typically made from concrete reinforced by steel tensioning cables. Where such bridges carry vehicle traffic, a certain degree of stiffness is required to prevent excessive flexure of the structure, obtained by stressing the concrete in compression.
This is an alphabetical list of articles pertaining specifically to structural engineering. For a broad overview of engineering, please see List of engineering topics. For biographies please see List of engineers.
The Trezzo sull'Adda Bridge or Trezzo Bridge was a medieval bridge at Trezzo sull'Adda in Lombardy, Italy, spanning the Adda river. Completed in 1377, the single-arch bridge held the record for the largest span for over four hundred years, until the beginnings of the Industrial Age, while it was not until the early 20th century that masonry bridges with larger openings were constructed.
The Flehe Bridge, is a single tower cable stayed bridge over the [[Rhine] near Düsseldorf. It connects the A 46 motorway from the left bank of the Rhine with the Bergisches Land on the right bank and the south of Düsseldorf. At the same time it forms the southern part of the motorway ring around Düsseldorf. It includes pedestrian and cycle paths.
The Hulme Arch Bridge in Hulme, Manchester, England, supports Stretford Road as it passes over Princess Road, and is located at grid reference SJ838968. The construction of the bridge formed part of the regeneration of the Hulme district of Manchester, both by re-establishing the former route of Stretford Road, which had been cut into two halves by the construction of Princess Road in 1969, and by providing a local landmark. The location was previously occupied by a footbridge.
Structural engineering depends upon a detailed knowledge of loads, physics and materials to understand and predict how structures support and resist self-weight and imposed loads. To apply the knowledge successfully structural engineers will need a detailed knowledge of mathematics and of relevant empirical and theoretical design codes. They will also need to know about the corrosion resistance of the materials and structures, especially when those structures are exposed to the external environment.
The Puente de los Franceses railway viaduct is located in Madrid, Spain. Comprising five semi-circular brick skew arches, it was built in the second half of the 19th century to carry the railway line from the north across the River Manzanares.
The first Wearmouth Bridge was a bridge across the River Wear in Sunderland, England and the second major bridge to be made from cast iron. It was considered one of the wonders of the industrial age, and was described by Nikolaus Pevsner as being 'a triumph of the new metallurgy and engineering ingenuity [...] of superb elegance'.
BBR Construction, BBR System, Bureau BBR, BBR Group or BBR VT International is a Swiss construction firm specializing in cable construction projects such as suspension bridges and tramways. They built the first carbon fibre stay cable bridge. The firm was started in 1944 by three engineers, Max Birkenmaier, Antonio Brandestini and Mirko Robin Ros. Their stay cable technology has been applied to over 400 major structures around the world.
The Puente de Isabel II, Puente de Triana or Triana Bridge, is a metal arch bridge in Seville, Spain, that connects the Triana neighbourhood with the centre of the city. It crosses the Canal de Alfonso XIII, one of the arms of the River Guadalquivir that isolate Triana as an almost-island.