Ancestor | Truss bridge |
---|---|
Related | Bascule bridge, swing bridge, folding bridge, retractable bridge |
Descendant | Submersible bridge, table bridge |
Carries | Automobile, pedestrians, truck, light rail, heavy rail |
Span range | Short |
Material | Steel |
Movable | Yes |
Design effort | medium |
Falsework required | Depends upon degree of prefabrication |
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 vertical lift offers several benefits over other movable bridges such as the bascule and swing-span bridges. Generally speaking, they cost less to build for longer moveable spans. [1] The counterweights in a vertical lift are only required to be equal to the weight of the deck, whereas bascule bridge counterweights must weigh several times as much as the span being lifted. As a result, heavier materials can be used in the deck, and so this type of bridge is especially suited for heavy railroad use. The biggest disadvantage to the vertical-lift bridge (in comparison with many other designs) is the height restriction for vessels passing under it, due to the deck remaining suspended above the passageway.
Most vertical-lift bridges use towers, each equipped with counterweights. An example of this kind was built in Portland, Oregon, United States in 1912.
Another design uses balance beams to lift the deck, with pivoting bascules located on the top of the lift towers. [2]
The Steel Bridge is a through truss, double-deck vertical-lift bridge across the Willamette River in Portland, Oregon, United States, opened in 1912. Its lower deck carries railroad and bicycle/pedestrian traffic, while the upper deck carries road traffic, and light rail (MAX), making the bridge one of the most multimodal in the world. It is the only double-deck bridge with independent lifts in the world and the second oldest vertical-lift bridge in North America, after the nearby Hawthorne Bridge. The bridge links the Rose Quarter and Lloyd District in the east to Old Town Chinatown neighborhood in the west.
The Hawthorne Bridge is a truss bridge with a vertical lift that spans the Willamette River in Portland, Oregon, joining Hawthorne Boulevard and Madison Street. It is the oldest vertical-lift bridge in operation in the United States and the oldest highway bridge in Portland. It is also the busiest bicycle bridge in Oregon, with over 8,000 cyclists and 800 TriMet buses daily. It was added to the National Register of Historic Places in November 2012.
Joseph Baermann Strauss was a German-American structural engineer who revolutionized the design of bascule bridges. He was the chief engineer of the Golden Gate Bridge in San Francisco, California.
A swing bridge is a movable bridge that can be rotated horizontally around a vertical axis. It has as its primary structural support a vertical locating pin and support ring, usually at or near to its center of gravity, about which the swing span can then pivot horizontally as shown in the animated illustration to the right.
A drawbridge or draw-bridge is a type of moveable bridge typically at the entrance to a castle or tower surrounded by a moat. In some forms of English, including American English, the word drawbridge commonly refers to all types of moveable bridges, such as bascule bridges, vertical-lift bridges and swing bridges, but this article concerns the narrower historical definition of the term where the bridge is used in a defensive structure.
A bascule bridge is a moveable bridge with a counterweight that continuously balances a span, or leaf, throughout its upward swing to provide clearance for boat traffic. It may be single- or double-leafed.
The Burnside Bridge is a 1926-built bascule bridge that spans the Willamette River in Portland, Oregon, United States, carrying Burnside Street. It is the second bridge at the same site to carry that name. It was added to the National Register of Historic Places in November 2012.
The Morrison Bridge is a bascule bridge that spans the Willamette River in Portland, Oregon. Completed in 1958, it is the third bridge at approximately the same site to carry that name. It is one of the most heavily used bridges in Portland. It was added to the National Register of Historic Places in November 2012.
The Broadway Bridge is a Rall-type bascule bridge spanning the Willamette River in Portland, Oregon, United States, built in 1913. It was Portland's first bascule bridge, and it continues to hold the distinction of being the longest span of its bascule design type in the world. It was added to the National Register of Historic Places in November 2012.
The BNSF Railway Bridge 5.1, also known as the St. Johns Railroad Bridge or the Willamette River Railroad Bridge, is a through truss railway bridge with a vertical lift that spans the Willamette River in Portland, Oregon, United States. Built by the Spokane, Portland and Seattle Railway (SP&S) and completed in 1908, it was originally a swing-span bridge, and its swing-span section was the longest in the world at the time. However, 81 years later the main span was converted from a swing-type to a vertical-lift type, in order to widen the navigation channel. The lift span is one of the highest and longest in the world. The bridge consists of five sections, with the two sections closest to the bank on each side fixed.
A moveable bridge, or movable bridge, is a bridge that moves to allow passage for boats or barges. In American English, the term is synonymous with drawbridge, and the latter is the common term, but drawbridge can be limited to the narrower, historical definition used in some other forms of English, in which drawbridge refers to only a specific type of moveable bridge often found in castles.
Portland architecture includes a number of notable buildings, a wide range of styles, and a few notable pioneering architects.
A submersible bridge is a type of movable bridge that lowers the bridge deck below the water level to permit waterborne traffic to use the waterway. This differs from a lift bridge or table bridge, which operate by raising the roadway. Two submersible bridges exist across the Corinth Canal in Greece, one at each end, in Isthmia and Corinth. They lower the centre span to 8 metres below water level when they give way to ships crossing the channel.
The Glimmer Glass Bridge is a county owned bridge in Monmouth County, New Jersey, United States. It carries traffic from Brielle Road over the Glimmer Glass, a navigable tidal inlet of the Manasquan River, between Manasquan and Brielle. It has also been on the National Register of Historic Places, since 2008. Due to its age, Commercial vehicles cannot be driven over it. It also allows Bicycles and pedestrians to walk on the wooden sidewalk.
The Salford Quays lift bridge, also known as the Salford Quays Millennium footbridge or the Lowry bridge, is a 91.2-metre (299 ft) long vertical lift bridge spanning the Manchester Ship Canal between Salford and Trafford in Greater Manchester, England. The pedestrian bridge, which was completed in 2000, is near the terminus of the ship canal at the old Manchester Docks. It is sited beside The Lowry theatre and gallery and links Salford Quays and MediaCityUK to Trafford Wharf and the Imperial War Museum North. It has a lift of 18 metres (59 ft), allowing large watercraft to pass beneath.
Eighth Street Bridge is a road bridge over the Passaic River in northeastern New Jersey, United States. It connects the City of Passaic in Passaic County with the Borough of Wallington in Bergen County and is jointly owned by both counties. The bridge connects Eighth Street in Passaic with County Route 507 in Wallington.
The Tramway Lift Bridge over Maroochy River is a heritage-listed railway bridge at Store Road, Nambour, Sunshine Coast Region, Queensland, Australia. It was built in 1921. It was added to the Queensland Heritage Register on 7 February 2005.
A double-beam drawbridge, seesaw or folding bridge is a movable bridge. It opens by rotation about a horizontal axis parallel to the water. Historically, the double-beam drawbridge has emerged from the drawbridge. Unlike a drawbridge, a double-beam drawbridge has counterweights, so that opening requires much less energy.