53-614: The Zhongxian Yangtze River Bridge is a suspension bridge over the Yangtze River in Zhong County of Chongqing , China . Completed in 2001, the bridge has a total length 1,199.73 metres (3,936.1 ft) including a longest span of 560 metres (1,840 ft), which places the bridge among the longest suspension spans in the world . In 2006, the bridge received the Lu Ban Award for engineering excellence. This article about
106-410: A cable-stayed bridge in which the deck is in compression. Cable-stayed bridges and suspension bridges may appear to be similar, but are quite different in principle and in their construction. In suspension bridges, large main cables (normally two) hang between the towers and are anchored at each end to the ground. The main cables, which are free to move on bearings in the towers, bear the load of
159-533: A 214 m central span), is similar to the Sagar bridge. It is one of the longest of the parabolic arc chain type. The current Marlow suspension bridge was designed by William Tierney Clark and was built between 1829 and 1832, replacing a wooden bridge further downstream which collapsed in 1828. It is the only suspension bridge across the non-tidal Thames. The Széchenyi Chain Bridge , (designed in 1840, opened in 1849), spanning
212-492: A bridge has a tendency to collapse simply because of the gravitational forces acting on the materials of which the bridge is made. Live load refers to traffic that moves across the bridge as well as normal environmental factors such as changes in temperature, precipitation, and winds. Dynamic load refers to environmental factors that go beyond normal weather conditions, factors such as sudden gusts of wind and earthquakes. All three factors must be taken into consideration when building
265-468: A bridge. Silver Bridge (USA) was an eyebar chain highway bridge, built in 1928, that collapsed in late 1967, killing forty-six people. The bridge had a low-redundancy design that was difficult to inspect. The collapse inspired legislation to ensure that older bridges were regularly inspected and maintained. Following the collapse a bridge of similar design was immediately closed and eventually demolished. A second similarly-designed bridge had been built with
318-757: A bridge. The principles of suspension used on a large scale also appear in contexts less dramatic than road or rail bridges. Light cable suspension may prove less expensive and seem more elegant for a cycle or footbridge than strong girder supports. An example of this is the Nescio Bridge in the Netherlands, and the Roebling designed 1904 Riegelsville suspension pedestrian bridge across the Delaware River in Pennsylvania. The longest pedestrian suspension bridge, which spans
371-461: A half (38 mm) thick, rivetted together. The first wire-cable suspension bridge was the Spider Bridge at Falls of Schuylkill (1816), a modest and temporary footbridge built following the collapse of James Finley's nearby Chain Bridge at Falls of Schuylkill (1808). The footbridge's span was 124 m, although its deck was only 0.45 m wide. Development of wire-cable suspension bridges dates to
424-403: A higher margin of safety and remained in service until 1991. The Tacoma Narrows Bridge , (USA), 1940, was vulnerable to structural vibration in sustained and moderately strong winds due to its plate-girder deck structure. Wind caused a phenomenon called aeroelastic fluttering that led to its collapse only months after completion. The collapse was captured on film. There were no human deaths in
477-401: A long history in many mountainous parts of the world. Besides the bridge type most commonly called suspension bridges, covered in this article, there are other types of suspension bridges . The type covered here has cables suspended between towers , with vertical suspender cables that transfer the live and dead loads of the deck below, upon which traffic crosses. This arrangement allows
530-609: A pedestrian suspension bridge over the Machchhu River in the city of Morbi, Gujarat, India collapsed, leading to the deaths of at least 141 people. Westmoreland County, Pennsylvania Westmoreland County is a county in the Commonwealth of Pennsylvania , United States, located in the Pittsburgh Metropolitan Statistical Area . As of the 2020 census , the population was 354,663. The county seat
583-641: A proposal by Robert Stevenson for a bridge over the River Almond near Edinburgh . Roebling's Delaware Aqueduct (begun 1847) consists of three sections supported by cables. The timber structure essentially hides the cables; and from a quick view, it is not immediately apparent that it is even a suspension bridge. The main suspension cables in older bridges were often made from a chain or linked bars, but modern bridge cables are made from multiple strands of wire. This not only adds strength but improves reliability (often called redundancy in engineering terms) because
SECTION 10
#1732869013324636-538: A sequence generally described as follows. Depending on length and size, construction may take anywhere between a year and a half (construction on the original Tacoma Narrows Bridge took only 19 months) up to as long as a decade (the Akashi-Kaikyō Bridge's construction began in May 1986 and was opened in May 1998 – a total of twelve years). Suspension bridges are typically ranked by the length of their main span. These are
689-448: A specific bridge or group of bridges in China is a stub . You can help Misplaced Pages by expanding it . Suspension bridge A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. The first modern examples of this type of bridge were built in the early 1800s. Simple suspension bridges , which lack vertical suspenders, have
742-499: A temporary walkway. Poured sockets are used to make a high strength, permanent cable termination. They are created by inserting the suspender wire rope (at the bridge deck supports) into the narrow end of a conical cavity which is oriented in-line with the intended direction of strain. The individual wires are splayed out inside the cone or 'capel', and the cone is then filled with molten lead-antimony-tin (Pb80Sb15Sn5) solder. Most suspension bridges have open truss structures to support
795-507: Is Greensburg and the most populous community is Hempfield Township . It is named after Westmorland , a historic county of England . The county is part of the Southwest Pennsylvania region of the state. Formed from, successively, Lancaster , Northumberland , and later Bedford counties, Westmoreland County was founded on February 26, 1773, and was the first county in the colony of Pennsylvania whose entire territorial boundary
848-1245: Is land and 8.5 square miles (22 km ) (0.8%) is water. Westmoreland County is one of the 423 counties served by the Appalachian Regional Commission , and it is identified as part of "Greater Appalachia" by Colin Woodard in his book American Nations: A History of the Eleven Rival Regional Cultures of North America . Westmoreland has a humid continental climate ( Dfa / Dfb ). Average monthly temperatures in Greensburg range from 28.7 °F in January to 71.8 °F in July, while in Murrysville they range from 29.4 °F in January to 73.1 °F in July, in Latrobe they range from 28.9 °F in January to 72.0 °F in July, and in Ligonier they range from 28.1 °F in January to 71.1 °F in July. At
901-513: The 2010 census , there were 365,169 people, 153,650 households and 101,928 families residing in the county. The population density was 355.4 people per square mile (137.2 people/km ). There were 168,199 housing units at an average density of 163.7 units per square mile (63.2/km ). The racial makeup of the county was 95.3% White , 2.3% Black or African American , 0.1% Native American , 0.7% Asian , 0.03% Pacific Islander , 0.2% from other races , and 1.2% from two or more races. 0.9% of
954-458: The 39th Senate district by beating out incumbent Allen Kukovich . Then in 2008, Republican Tim Krieger picked up the 57th House district left open by the retirement of Democratic state representative Tom Tangretti. In 2010, both Pat Toomey and Tom Corbett won Westmoreland in their statewide bids. Also, the GOP gained control of two more State House districts, the 54th with Eli Evankovich and
1007-586: The 56th with George Dunbar . In 2011, the Republican Party swept all county row offices. A Democratic resurgence in 2015 gave that party a majority of the county commissioners. However, in the 2019 elections, Democratic elected officials lost that majority and carried only one row office. In 2020 the County Sheriff who was the lone Democrat who won a row office in 2019 switched party affiliations from Democratic to Republican. In 2021 Republicans carried all of
1060-806: The Dryburgh Abbey Bridge (1817) and 137 m Union Bridge (1820), with spans rapidly increasing to 176 m with the Menai Bridge (1826), "the first important modern suspension bridge". The first chain bridge on the German speaking territories was the Chain Bridge in Nuremberg . The Sagar Iron Suspension Bridge with a 200 feet span (also termed Beose Bridge) was constructed near Sagar, India during 1828–1830 by Duncan Presgrave, Mint and Assay Master. The Clifton Suspension Bridge (designed in 1831, completed in 1864 with
1113-797: The Mahakam River , located in Kutai Kartanegara Regency , East Kalimantan district on the Indonesia island of Borneo , was built in 1995, completed in 2001 and collapsed in 2011. Dozens of vehicles on the bridge fell into the Mahakam River . As a result of this incident, 24 people died and dozens of others were injured and were treated at the Aji Muhammad Parikesit Regional Hospital. Meanwhile, 12 people were reported missing, 31 people were seriously injured, and 8 people had minor injuries. Research findings indicate that
SECTION 20
#17328690133241166-606: The New Deal realignment and the turn of the century; however, Westmoreland has trended Republican at the national and statewide levels in the 21st century (in direct lockstep with most other Appalachian counties). In 2000, Republican George W. Bush became the first Republican to carry the county since 1972. Republicans have won the county in every election since, increasing the margin of victory in every successive election until 2020. Democratic Governor Ed Rendell lost Westmoreland in 2002 and 2006. In 2004 Republican Bob Regola flipped
1219-476: The 2022 Gubernatorial race, the cities of Greensburg, New Kensington, Latrobe, and Jeannette all voted for Democrat Josh Shapiro over Republican Doug Mastriano despite voting Republican in the 2020 Presidential election. Westmoreland County is administered by a three-member publicly elected commission. Each commissioner serves in four-year terms. Elections occur in the odd-numbered years that precede U.S. presidential elections. All three Commissioners are chosen in
1272-638: The River Danube in Budapest, was also designed by William Clark and it is a larger-scale version of Marlow Bridge. An interesting variation is Thornewill and Warham 's Ferry Bridge in Burton-on-Trent , Staffordshire (1889), where the chains are not attached to abutments as is usual, but instead are attached to the main girders, which are thus in compression. Here, the chains are made from flat wrought iron plates, eight inches (203 mm) wide by an inch and
1325-542: The River Paiva, Arouca Geopark , Portugal, opened in April 2021. The 516 metres bridge hangs 175 meters above the river. Where such a bridge spans a gap between two buildings, there is no need to construct towers, as the buildings can anchor the cables. Cable suspension may also be augmented by the inherent stiffness of a structure that has much in common with a tubular bridge . Typical suspension bridges are constructed using
1378-506: The U.S. It operated from 1978 to 1988. Westmoreland County has four Pennsylvania state parks . Under Pennsylvania law, there are four types of incorporated municipalities: cities , boroughs , townships , and, in at most two cases, towns . The following cities, boroughs, and townships are located in Westmoreland County: Census-designated places are geographical areas designated by the U.S. Census Bureau for
1431-599: The United States, the first major wire-cable suspension bridge was the Wire Bridge at Fairmount in Philadelphia, Pennsylvania. Designed by Charles Ellet Jr. and completed in 1842, it had a span of 109 m. Ellet's Niagara Falls suspension bridge (1847–48) was abandoned before completion. It was used as scaffolding for John A. Roebling 's double decker railroad and carriage bridge (1855). The Otto Beit Bridge (1938–1939)
1484-432: The bridge deck. Before the deck is installed, the cables are under tension from their own weight. Along the main cables smaller cables or rods connect to the bridge deck, which is lifted in sections. As this is done, the tension in the cables increases, as it does with the live load of traffic crossing the bridge. The tension on the main cables is transferred to the ground at the anchorages and by downwards compression on
1537-519: The collapse was largely caused by the construction failure of the vertical hanging clamp. It was also found that poor maintenance, fatigue in the cable hanger construction materials, material quality, and bridge loads that exceed vehicle capacity, can also have an impact on bridge collapse. In 2013 the Kutai Kartanegara Bridge rebuilt the same location and completed in 2015 with a Through arch bridge design. On 30 October 2022, Jhulto Pul ,
1590-517: The collapse; several drivers escaped their cars on foot and reached the anchorages before the span dropped. Yarmouth suspension bridge (England) was built in 1829 and collapsed in 1845, killing 79 people. Peace River Suspension Bridge (Canada), which was completed in 1943, collapsed when the north anchor's soil support for the suspension bridge failed in October 1957. The entire bridge subsequently collapsed. Kutai Kartanegara Bridge (Indonesia) over
1643-437: The deck to be level or to arc upward for additional clearance. Like other suspension bridge types, this type often is constructed without the use of falsework . The suspension cables must be anchored at each end of the bridge, since any load applied to the bridge is transformed into tension in these main cables. The main cables continue beyond the pillars to deck-level supports, and further continue to connections with anchors in
Zhongxian Yangtze River Bridge - Misplaced Pages Continue
1696-649: The expansion of iron, steel, and glass manufacturing. The 600-acre coke works for the Isabella Furnace were built in Cokeville (then Coketown) in the Spring of 1872. At one point, company "coal patches" (towns built for miners) represented about one-third of the county's settlements. A major strike by coal miners represented by the United Mine Workers of America took place in 1910–1911. Sixteen people were killed in
1749-571: The failure of a few flawed strands in the hundreds used pose very little threat of failure, whereas a single bad link or eyebar can cause failure of an entire bridge. (The failure of a single eyebar was found to be the cause of the collapse of the Silver Bridge over the Ohio River .) Another reason is that as spans increased, engineers were unable to lift larger chains into position, whereas wire strand cables can be formulated one by one in mid-air from
1802-434: The ground. The roadway is supported by vertical suspender cables or rods, called hangers. In some circumstances, the towers may sit on a bluff or canyon edge where the road may proceed directly to the main span. Otherwise, the bridge will typically have two smaller spans, running between either pair of pillars and the highway, which may be supported by suspender cables or their own trusswork . In cases where trusswork supports
1855-530: The live loads. In an underspanned suspension bridge, also called under-deck cable-stayed bridge, the main cables hang entirely below the bridge deck, but are still anchored into the ground in a similar way to the conventional type. Very few bridges of this nature have been built, as the deck is inherently less stable than when suspended below the cables. Examples include the Pont des Bergues of 1834 designed by Guillaume Henri Dufour ; James Smith's Micklewood Bridge; and
1908-434: The population were Hispanic or Latino of any race. There were 153,650 households, of which 24.5% had children under the age of 18 living with them, 52.2% were married couples living together, 10.0% had a female householder with no husband present, and 33.7% were non-families. 29.0% of all households were made up of individuals, and 13.3% had someone living alone who was 65 years of age or older. The average household size
1961-592: The roadbed, particularly owing to the unfavorable effects of using plate girders, discovered from the Tacoma Narrows Bridge (1940) bridge collapse. In the 1960s, developments in bridge aerodynamics allowed the re-introduction of plate structures as shallow box girders , first seen on the Severn bridge , built 1961–1966. In the picture of the Yichang Bridge , note the very sharp entry edge and sloping undergirders in
2014-559: The row offices including defeating the incumbent District Attorney and County Coroner, following the 2021 election the minority County Commissioner was the only Democrat to hold Countywide office. In 2023 Republicans retained their majority on the Board of Commissioners and held every row office. As of 2020 , the only majority-Democratic cities within the county are Arnold and Monessen . That being said, local Democrats running statewide sometimes win additional cities and boroughs. For example, in
2067-467: The same election, and voters may vote for no more than two candidates. By state law, the commission must have a minority party guaranteeing a political split on the commission. The Commissioners are responsible for the management of the fiscal and administrative functions of the county. School districts: According to EdNA Coal mining became a major industry in the county after the Civil War, followed by
2120-496: The spans, there will be very little arc in the outboard main cables. The earliest suspension bridges were ropes slung across a chasm, with a deck possibly at the same level or hung below the ropes such that the rope had a catenary shape. The Tibetan siddha and bridge-builder Thangtong Gyalpo originated the use of iron chains in his version of simple suspension bridges . In 1433, Gyalpo built eight bridges in eastern Bhutan . The last surviving chain-linked bridge of Gyalpo's
2173-505: The strike. In 2020, the top industries in the county were health care and social services (16.3% of jobs), manufacturing (13.8%), and retail trade (13.7%). Mining comprised less than 1% of the jobs in the county. Westmoreland County is now believed to be the site of over 100 abandoned mines. Volkswagen's Westmoreland plant near New Stanton in Westmoreland County was the first foreign-owned factory mass-producing automobiles in
Zhongxian Yangtze River Bridge - Misplaced Pages Continue
2226-401: The suspension bridge shown. This enables this type of construction to be used without the danger of vortex shedding and consequent aeroelastic effects, such as those that destroyed the original Tacoma Narrows bridge. Three kinds of forces operate on any bridge: the dead load, the live load, and the dynamic load. Dead load refers to the weight of the bridge itself. Like any other structure,
2279-501: The temporary simple suspension bridge at Annonay built by Marc Seguin and his brothers in 1822. It spanned only 18 m. The first permanent wire cable suspension bridge was Guillaume Henri Dufour 's Saint Antoine Bridge in Geneva of 1823, with two 40 m spans. The first with cables assembled in mid-air in the modern method was Joseph Chaley 's Grand Pont Suspendu in Fribourg , in 1834. In
2332-508: The ten bridges with the longest spans, followed by the length of the span and the year the bridge opened for traffic: (Chronological) Broughton Suspension Bridge (England) was an iron chain bridge built in 1826. One of Europe's first suspension bridges, it collapsed in 1831 due to mechanical resonance induced by troops marching in step. As a result of the incident, the British Army issued an order that troops should "break step" when crossing
2385-489: The towers. In cable-stayed bridges, the towers are the primary load-bearing structures that transmit the bridge loads to the ground. A cantilever approach is often used to support the bridge deck near the towers, but lengths further from them are supported by cables running directly to the towers. By design, all static horizontal forces of the cable-stayed bridge are balanced so that the supporting towers do not tend to tilt or slide and so must only resist horizontal forces from
2438-448: The use of iron chains it is thought that Gyalpo used ropes from twisted willows or yak skins. He may have also used tightly bound cloth. The Inca used rope bridges , documented as early as 1615. It is not known when they were first made. Queshuachaca is considered the last remaining Inca rope bridge and is rebuilt annually. The first iron chain suspension bridge in the Western world
2491-423: The weight of the cables is small compared to the weight of the deck. One can see the shape from the constant increase of the gradient of the cable with linear (deck) distance, this increase in gradient at each connection with the deck providing a net upward support force. Combined with the relatively simple constraints placed upon the actual deck, that makes the suspension bridge much simpler to design and analyze than
2544-524: Was 2.32, and the average family size was 2.86. 22.3% of the population were under 18, 5.1% from 18 to 24, 22.4% from 25 to 44, 31.3% from 45 to 64, and 18.9% who were 65 years of age or older. The median age was 45.1 years. For every 100 females, there were 94.8 males. For every 100 females age 18 and over, there were 92.3 males. As of March 4, 2024, there are 245,262 registered voters in Westmoreland County. Chart of Voter Registration The Democratic Party historically dominated county-level politics between
2597-492: Was located west of the Allegheny Mountains . Westmoreland County originally included the present-day counties of Fayette , Washington , Greene , and parts of Beaver , Allegheny , Indiana , and Armstrong counties. Formed from Lancaster, Northumberland, and later Bedford counties, Westmoreland County was founded on February 26, 1773, and was the first county in the Pennsylvania colony whose entire territorial boundary
2650-483: Was located west of the Allegheny Mountains. Westmoreland County originally included the present-day counties of Fayette, Washington, Greene, and parts of Beaver, Allegheny, Indiana, and Armstrong counties. It is named after Westmorland, a historic county of England. According to the U.S. Census Bureau , the county has a total area of 1,036 square miles (2,680 km ), of which 1,028 square miles (2,660 km )
2703-530: Was the Jacob's Creek Bridge (1801) in Westmoreland County, Pennsylvania , designed by inventor James Finley . Finley's bridge was the first to incorporate all of the necessary components of a modern suspension bridge, including a suspended deck which hung by trusses. Finley patented his design in 1808, and published it in the Philadelphia journal, The Port Folio , in 1810. Early British chain bridges included
SECTION 50
#17328690133242756-529: Was the Thangtong Gyalpo Bridge in Duksum en route to Trashi Yangtse , which was finally washed away in 2004. Gyalpo's iron chain bridges did not include a suspended-deck bridge , which is the standard on all modern suspension bridges today. Instead, both the railing and the walking layer of Gyalpo's bridges used wires. The stress points that carried the screed were reinforced by the iron chains. Before
2809-404: Was the first modern suspension bridge outside the United States built with parallel wire cables. Two towers/pillars, two suspension cables, four suspension cable anchors, multiple suspender cables, the bridge deck. The main cables of a suspension bridge will form a catenary when hanging under their own weight only. When supporting the deck, the cables will instead form a parabola , assuming
#323676