Mount Washington Transit Tunnel
Mount Washington Transit Tunnel is an important public transportation link in Pittsburgh, United States. The 3,500-foot tunnel connects Station Square to South Hills Junction, is used only by Pittsburgh Light Rail cars and buses of the Port Authority of Allegheny County; the tunnel was built by Booth and Flinn for Pittsburgh Railways to overcome the barrier of Mount Washington to the development of electric streetcar services to points south. Excavation was started October 6, 1902, the tunnel was opened December 1, 1904; the tunnel was paved around the rails to allow for joint use by bus and trolley traffic in 1973. The Transit tunnel is located in line with the Pittsburgh and Castle Shannon Tunnel, at a much higher elevation; that tunnel was a coal mine accessed from the top of an incline on the river side. It was opened at the back and used to run through to other coal mines in the Saw Mill Run valley; the Pittsburgh and Castle Shannon Railroad operated passenger service through the tunnel from 1873 until 1892, after which passengers journeyed instead via the new Castle Shannon Incline, while coal trains continued to use the old route through the tunnel.
From 1909 the main passenger service became Pittsburgh Railways streetcars running from the Transit Tunnel into the Castle Shannon route at South Hills Junction. Because of the related nature of the two tunnels, an urban legend persists that the Transit Tunnel was a coal mine. Two spectacular runaway accidents are associated with the tunnel, on a steep gradient averaging over 6 percent, curves as the north portal is reached. On December 24, 1917, Knoxville service car 4236 ran away downhill after becoming detached from the wire and derailed and overturned on the curve into Carson Street; the car slid on its side until hitting a telegraph pole. Twenty-one people were killed and 80 were injured. On October 29, 1987, a 1700-series all-electric PCC car began to exceed the tunnel's speed limit as it entered the south portal after departing South Hills Junction; the operator, realizing the car could neither stop nor take the sharp curve from the transitway to the Panhandle Bridge ramp, ordered all the passengers to move to the back, radioed the PAT central dispatcher to clear Station Square.
The car left the rails and took Smithfield Street instead, crossing Carson Street, sideswiping a PAT bus and a truck, knocking out a fire hydrant. Miraculously, the car stayed on its wheels, stopped next to the Pittsburgh History & Landmarks Foundation, the former Pittsburgh and Lake Erie station building at Station Square. Thirty-seven people were injured, four but there were no fatalities. All three braking systems on the car had failed: the drum and magnetic rail brakes. Most of the 1700 series cars were found to have electrical defects, prompting PAT to retire all of their remaining PCC's that had not been rebuilt as 4000 series cars. PAT was left with a shortage of cars, which contributed to the closure of the Overbrook line in 1993. Pittsburgh Railways Pittsburgh Light Rail South Busway Pittsburgh and Castle Shannon Tunnel 40.4221°N 80.0063°W / 40.4221.
Fort Pitt Tunnel
The Fort Pitt Tunnel carries traffic on Interstate 376, U. S. Route 22, US 30, US 19 Truck between Downtown Pittsburgh and the West End neighborhood in the U. S. state of Pennsylvania. Traveling beneath Mount Washington, the structure is divided into a two lane inbound tunnel and two lane outbound tunnel; the inbound tunnel flows onto the top deck of the double-deck Fort Pitt Bridge, opposite traffic from the lower deck using the outbound tunnel. To accommodate the bridge, the northeast portals of the parallel tunnels open at two levels. "FORT PITT TUNNEL" is mounted in brushed steel letters on a grey granite facade above the southwest portals, with larger scaled capital letters used on the facade above the northeast portals. Before entering the southwest end of the inbound tunnel, travelers see a commonplace view of Southwestern Pennsylvania's hills, but at the northeast end, travelers emerge to a panorama of Pittsburgh's Golden Triangle and surrounding skyline, the view cited by The New York Times as "the best way to enter an American city".
The vantage was the inspiration for the news opening on Pittsburgh's KDKA-TV for several years in the 1980s and 1990s, is referenced in Stephen Chbosky's novel The Perks of Being a Wallflower. The Fort Pitt Tunnel opened in 1960, a year after the adjoining Fort Pitt Bridge, it is the third longest automobile tunnel in the City of Pittsburgh, following the Liberty Tunnels and the Squirrel Hill Tunnel. And it is one of four major tunnels passing beneath Mount Washington, including the Liberty Tunnels and the Wabash Tunnel for automobiles, the Mount Washington Transit Tunnel for public transportation. Before the existence of the Fort Pitt Tunnels, South Hills commuters travelled around the Banksville Circle, the northern terminus of Banksville Road and western terminus of Saw Mill Run Blvd at the time. On July 11, 1954, contracts were awarded for the basic design of the Fort Pitt Tunnels; the groundbreaking ceremony for the Fort Pitt tunnel was held April 17, 1957 and drilling began August 28 of the same year.
In April 1960 construction on the tunnels was complete and they opened for the first time at 11 a.m. on September 1, 1960, with a dedication ceremony on the southwestern portal by Governor Lawrence, Pennsylvania Transportation Secretary Park H. Martin and Pittsburgh Mayor Joseph M. Barr followed by a "christening" of the tunnels in which the Governor led a caravan of antique cars through; the tunnel cost $17 million. On Thursday, May 31, 2007, a bomb threat shut down the Fort Pitt Tunnel along with the Liberty and Squirrel Hill tunnels, causing a major traffic jam; the tunnel provided AM reception in 1960, but due to design repairs it was discontinued until 1986. It was improved to cover the entire tunnel with strong reception in March 1997. Since August 1987, the tunnels have provided cellular phone reception. With the help of Carnegie Mellon University graduate students, the tunnel has provided FM reception since July 2005 as well as having its AM signals upgraded at that time. In 2015, the original flat ceiling was removed due to its poor condition.
3,614 ft in length 28 ft wide 13.5 ft vertical clearance Serves nearly 107,000 vehicles per day. There are 1,788 light fixtures with 3,576 bulbs. There are 187,200 sq ft of tiled surface to wash. Pittsburgh portal Travel Channel video Video of the tunnel 40.43191°N 80.02440°W / 40.43191.
Self-anchored suspension bridge
A self-anchored suspension bridge is a suspension bridge in which the main cables attach to the ends of the deck, rather than to the ground via large anchorages. The design is well-suited for construction atop elevated piers, or in areas of unstable soils where anchorages would be difficult to construct. Difference between types of bridges The load path of the self-anchored suspension bridge converts vertical loads into tension forces in the main cables which are countered by compressive forces in the towers and deck; the system balances forces internally without external anchorage requirements making it suitable for sites where large horizontal forces are difficult to anchor. This is similar to the method used in a tied-arch bridge where arch member compression is balanced by tension in the deck; the self-anchored suspension bridge form originated in the mid-19th century, with a published description by Austrian engineer Josef Langer in 1859 and U. S. Patent No. 71,955 by American engineer Charles Bender in 1867.
The form was applied to a handful of Rhine River crossings in Germany during the first half of the twentieth century. The SAS portion of the eastern span replacement of the San Francisco–Oakland Bay Bridge became self-supporting in November 2012, with a 385 m span; this is a half-span as the bridge has only a single tower. It is the largest SAS bridge in the world.the Konohana Bridge in Japan and the Yeoungjong Grand Bridge in South Korea, both have a central span of 300 m. The Three Sisters Bridges of Pittsburgh are the earliest examples of this bridge type in the US; the Chelsea Bridge in London, England. The Gagarin Street Bridge in Arkhangelsk, Russia; the nature of the self-anchored suspension bridge necessitates the temporary construction of falsework, in the form of compression struts or an underdeck, before work begins on the permanent structure. This requirement is inherent in the structure's definition. In the absence of suspension via cableage, the deck of a suspension bridge is incapable of self-support.
On a suspension bridge of the more usual earth-anchored type, both of the primary cable's anchorages exist prior to construction in the form of solid terrain. In the self-anchored suspension bridge, the cable must be anchored to the bridge deck, which has yet to be built and will not bear its own weight; as in a traditional suspension bridge, the primary cable type may be multiple parallel independent cables as in the image at right of the Hutsonville Bridge, or eyebars, or a more conventional composite cable. Eastern span replacement of the San Francisco–Oakland Bay Bridge Seventh Street Bridge at pghbridges.com List of self-anchored suspension bridges at Structurae.de Yeonglong Grand Bridge A two tower, three span self-anchored bridge
Cork Run Tunnel
The Cork Run Tunnel known as the Berry Street Tunnel, is one of nine tunnels built in Pittsburgh, Pennsylvania on the original Pittsburgh and Steubenville Railroad. The tunnel was built beginning in 1851 as a single-track bore 2,100 feet long, approached by deep open cuts, to connect central Pittsburgh with points to the west, on the south side of the Ohio River. A shaft was sunk from the overlying ridge to a point near the midpoint of the tunnel to speed construction and to provide ventilation. Work was suspended in 1856 due to financial troubles, resumed in 1862; the tunnel was completed in 1865. Upon completion it was apparent that the tunnel needed two lines; the tunnel was widened starting in 1870 for two tracks, was completed in 1873. The tunnel continued to represent a bottleneck, since large cars could not pass each other without causing derailments, which happened frequently. By 1889 work began on the Ohio Connecting Railway to relieve the tunnel. At the same time, the Cork's Run valley was filled in to build the Sheraden Yards, feeding the Cork Run Tunnel.
By 1906 the tunnel lining had deteriorated, becoming unstable and requiring continuous repair. Since the tunnel was so narrow, workers had to take shelter. At least one fatal work accident happened, several cave-ins closed the tunnel. Around 1900 a 300-foot section of the tunnel was cut open to the sky at the Pittsburgh end. By 1947 the Cork Run Tunnel was the only tunnel in the railroad's Panhandle Division that had not been "daylighted," cut open to the sky along its entire length; the tunnel was refurbished and re-opened in 1995 to serve as the link between Pittsburgh's Sheraden neighborhood and the community of Ingram on the Port Authority of Allegheny County's West Busway. Historic American Buildings Survey No. PA-382, "Cork Run Tunnel, Pittsburgh & Steubenville Railroad, from Chartiers Avenue Bridge heading 2371' west, Allegheny County, PA", 9 photos, 21 data pages, 2 photo caption pages Berry Street Tunnel at Pghbridges.com
The Ohio River is a 981-mile long river in the midwestern United States that flows southwesterly from western Pennsylvania south of Lake Erie to its mouth on the Mississippi River at the southern tip of Illinois. It is the second largest river by discharge volume in the United States and the largest tributary by volume of the north-south flowing Mississippi River that divides the eastern from western United States; the river flows through or along the border of six states, its drainage basin includes parts of 15 states. Through its largest tributary, the Tennessee River, the basin includes several states of the southeastern U. S, it is the source of drinking water for three million people. The lower Ohio River just below Louisville is obstructed by rapids known as the Falls of the Ohio where the water level falls 26ft. in 2 miles and is impassible for navigation. The McAlpine Locks and Dam, a shipping canal bypassing the rapids, now allows commercial navigation from the Forks of the Ohio at Pittsburgh to the Port of New Orleans at the mouth of the Mississippi on the Gulf of Mexico.
The name "Ohio" comes from the Ohi: yo', lit. "Good River". Discovery of the Ohio River may be attributed to English explorers from Virginia in the latter half of the 17th century. In his Notes on the State of Virginia published in 1781–82, Thomas Jefferson stated: "The Ohio is the most beautiful river on earth, its current gentle, waters clear, bosom smooth and unbroken by rocks and rapids, a single instance only excepted." In the late 18th century, the river was the southern boundary of the Northwest Territory. It became a primary transportation route for pioneers during the westward expansion of the early U. S; the river is sometimes considered as the western extension of the Mason–Dixon Line that divided Pennsylvania from Maryland, thus part of the border between free and slave territory, between the Northern and Southern United States or Upper South. Where the river was narrow, it was the way to freedom for thousands of slaves escaping to the North, many helped by free blacks and whites of the Underground Railroad resistance movement.
The Ohio River is a climatic transition area, as its water runs along the periphery of the humid subtropical and humid continental climate areas. It is inhabited by flora of both climates. In winter, it freezes over at Pittsburgh but farther south toward Cincinnati and Louisville. At Paducah, Kentucky, in the south, near the Ohio's confluence with the Mississippi, it is ice-free year-round; the name "Ohio" comes from the Seneca language, Ohi:yo', a proper name derived from ohiːyoːh, therefore translating to "Good River". "Great river" and "large creek" have been given as translations. Native Americans, including the Lenni Lenape and Iroquois, considered the Ohio and Allegheny rivers as the same, as is suggested by a New York State road sign on Interstate 86 that refers to the Allegheny River as Ohi:yo'. An earlier Miami-Illinois language name was applied to the Ohio River, Mosopeleacipi. Shortened in the Shawnee language to pelewa thiipi, spelewathiipi or peleewa thiipiiki, the name evolved through variant forms such as "Polesipi", "Peleson", "Pele Sipi" and "Pere Sipi", stabilized to the variant spellings "Pelisipi", "Pelisippi" and "Pellissippi".
Applied just to the Ohio River, the "Pelisipi" name was variously applied back and forth between the Ohio River and the Clinch River in Virginia and Tennessee. In his original draft of the Land Ordinance of 1784, Thomas Jefferson proposed a new state called "Pelisipia", to the south of the Ohio River, which would have included parts of present-day Eastern Kentucky and West Virginia; the river had great significance in the history of the Native Americans, as numerous civilizations formed along its valley. For thousands of years, Native Americans used the river as a major trading route, its waters connected communities. In the five centuries before European conquest, the Mississippian culture built numerous regional chiefdoms and major earthwork mounds in the Ohio Valley, such as Angel Mounds near Evansville, Indiana, as well as in the Mississippi Valley and the Southeast; the Osage, Omaha and Kaw lived in the Ohio Valley, but under pressure from the Iroquois to the northeast, migrated west of the Mississippi River in the 17th century to territory now defined as Missouri and Oklahoma.
The discovery and traversal of the Ohio River by Europeans admits of several possibilities, all in the latter half of the 17th century. Virginian Englishman Abraham Wood's trans-Appalachian expeditions between 1654 and 1664; the first person to traverse the length of the river, from the headwaters of the Allegheny to its mouth on the Mississippi, was a Dutch trader from New York, Arnout Viele, in 1692. In 1749, Great Britain established the Ohio Company to trade in the area. Exploration of the territory and trade with the Indians in the region near the Forks brought British colonials from both Pennsylvania and Virginia across the mountains, both colonies claimed the territory; the movement across the Allegheny Mountains of British settlers and the claims of the area near modern day Pittsburgh led to conflict with the French, who had forts in the Ohio River Valley. This conflict was called the Indian War. In 17
Pittsburgh is a city in the Commonwealth of Pennsylvania in the United States, is the county seat of Allegheny County. As of 2018, a population of 308,144 lives within the city limits, making it the 63rd-largest city in the U. S; the metropolitan population of 2,362,453, is the largest in both the Ohio Valley and Appalachia, the second-largest in Pennsylvania, the 26th-largest in the U. S. Pittsburgh is located in the south west of the state, at the confluence of the Allegheny and Ohio rivers. Pittsburgh is known both as "the Steel City" for its more than 300 steel-related businesses and as the "City of Bridges" for its 446 bridges; the city features 30 skyscrapers, two inclined railways, a pre-revolutionary fortification and the Point State Park at the confluence of the rivers. The city developed as a vital link of the Atlantic coast and Midwest, as the mineral-rich Allegheny Mountains made the area coveted by the French and British empires, Whiskey Rebels, Civil War raiders. Aside from steel, Pittsburgh has led in manufacturing of aluminum, shipbuilding, foods, transportation, computing and electronics.
For part of the 20th century, Pittsburgh was behind only New York and Chicago in corporate headquarters employment. S. stockholders per capita. America's 1980s deindustrialization laid off area blue-collar workers and thousands of downtown white-collar workers when the longtime Pittsburgh-based world headquarters moved out; this heritage left the area with renowned museums, medical centers, research centers, a diverse cultural district. Today, Apple Inc. Bosch, Uber, Autodesk, Microsoft and IBM are among 1,600 technology firms generating $20.7 billion in annual Pittsburgh payrolls. The area has served as the long-time federal agency headquarters for cyber defense, software engineering, energy research and the nuclear navy; the area is home to 68 colleges and universities, including research and development leaders Carnegie Mellon University and the University of Pittsburgh. The nation's eighth-largest bank, eight Fortune 500 companies, six of the top 300 U. S. law firms make their global headquarters in the area, while RAND, BNY Mellon, FedEx, Bayer and NIOSH have regional bases that helped Pittsburgh become the sixth-best area for U.
S. job growth. In 2015, Pittsburgh was listed among the "eleven most livable cities in the world"; the region is a hub for Environmental Design and energy extraction. In 2019, Pittsburgh was deemed “Food City of the Year” by the San Francisco-based restaurant and hospitality consulting firm af&co. Many restaurants were mentioned favorable, among them were Superior Motors in Braddock, Driftwood Oven in Lawrenceville, Spork in Bloomfield, Fish nor Fowl in Garfield and Bitter Ends Garden & Luncheonette in Bloomfield. Pittsburgh was named in 1758 by General John Forbes, in honor of British statesman William Pitt, 1st Earl of Chatham; as Forbes was a Scot, he pronounced the name PITS-bər-ə. Pittsburgh was incorporated as a borough on April 22, 1794, with the following Act: "Be it enacted by the Pennsylvania State Senate and Pennsylvania House of Representatives of the Commonwealth of Pennsylvania... by the authority of the same, that the said town of Pittsburgh shall be... erected into a borough, which shall be called the borough of Pittsburgh for ever."
From 1891 to 1911, the city's name was federally recognized as "Pittsburg", though use of the final h was retained during this period by the city government and other local organizations. After a public campaign, the federal decision to drop the h was reversed; the area of the Ohio headwaters was long inhabited by the Shawnee and several other settled groups of Native Americans. The first known European to enter the region was the French explorer/trader Robert de La Salle from Quebec during his 1669 expedition down the Ohio River. European pioneers Dutch, followed in the early 18th century. Michael Bezallion was the first to describe the forks of the Ohio in a 1717 manuscript, that year European fur traders established area posts and settlements. In 1749, French soldiers from Quebec launched an expedition to the forks to unite Canada with French Louisiana via the rivers. During 1753–54, the British hastily built Fort Prince George before a larger French force drove them off; the French built Fort Duquesne based on LaSalle's 1669 claims.
The French and Indian War, the North American front of the Seven Years' War, began with the future Pittsburgh as its center. British General Edward Braddock was dispatched with Major George Washington as his aide to take Fort Duquesne; the British and colonial force were defeated at Braddock's Field. General John Forbes took the forks in 1758. Forbes began construction on Fort Pitt, named after William Pitt the Elder while the settlement was named "Pittsborough". During Pontiac's Rebellion, native tribes conducted a siege of Fort Pitt for two months until Colonel Henry Bouquet relieved it after the Battle of Bushy Run. Fort Pitt is notable as the site of an early use of smallpox for biological warfare. Lord Jeffery Amherst ordered blankets contaminated from smallpox victims to be distributed in 1763 to the tribes surrounding the fort; the disease spread into other areas, infected other tribes, killed hundreds of thousands. During this period, the powerful nations of the Iroquois Confederacy, based in New York, had maintained control of much of the Ohio Valley as hunting grounds by right of conquest after defeating other tribes.
By the terms of the 1768 Treaty of
Pittsburgh Light Rail
The Pittsburgh Light Rail is a 26.2-mile light rail system in Pittsburgh, Pennsylvania. The system is linear in a north-south direction, with one terminus just north of Pittsburgh's central business district and two termini in the South Hills; the system is operated by the Port Authority of Allegheny County. It is the successor system to the streetcar network operated by Pittsburgh Railways, the oldest portions of which date to 1903; the Pittsburgh light rail lines are vestigial from the city's streetcar days, is one of only three light rail systems in the United States that continues to use the Pennsylvania Trolley gauge rail on its lines instead of 4 ft 8 1⁄2 in standard gauge. Pittsburgh is one of the few North American cities that have continued to operate light rail systems in an uninterrupted evolution from the first-generation streetcar era, along with Boston, New Orleans, Philadelphia, San Francisco and Toronto. In the early 1960s, Pittsburgh had the largest surviving streetcar system in the United States, with the owned Pittsburgh Railways Company operating more than 600 PCC cars on 41 routes.
In 1964 the system was acquired by the Port Authority of Allegheny County, which converted most routes to buses. By the early 1970s, only a handful of streetcar routes remained, most of which used the Mt. Washington Transit Tunnel just south of the Monongahela River to reach the South Hills area. At that time, Port Authority planners were determined to scrap the rail system in favor of busways and an automated guideway transit system developed by Westinghouse Electric called Skybus. Community opposition rallied against the plan and in favor of retaining the electric rail trolley system and upgrading it into modern LRT. In the end, the LRT option was adopted for the South Hills suburbs, along with development of a busway system for the eastern and western suburbs; the modern subway in downtown Pittsburgh between Steel Plaza and First Avenue stations uses the Pittsburgh & Steubenville Extension Railroad Tunnel, which began construction in 1863. Rail lines had been a staple of the city and region since the late 19th century, the idea of a downtown to Oakland or East Liberty subway had been considered since at least the 1910s.
A public referendum was passed to fund such a subway with an initial investment of $6 million on July 8, 1919, another $5.5 million subway plan was finalized at City Hall in meetings on March 28, 1932, the public/private Allegheny Conference presented detailed plans and funding for a subway system on June 4, 1947. Pittsburgh Railways was one of the predecessors to the Port Authority of Allegheny County, it had the third largest fleet in North America. It had 68 street car routes, of which only three are used by the Port Authority as light rail routes; the oldest portions of these old Pittsburgh Railways routes now served by the Pittsburgh Light Rail system date to 1903-1909. With the Port Authority's Transit Development Plan, many route names will be changed to its original, such as the 41D Brookline becoming the 39 Brookline. Many of the streetcar routes have been remembered in the route names of many Port Authority buses. 1895 to 1905 was a time of consolidation for the numerous street railways serving Pittsburgh.
On July 24, 1895 the Consolidated Traction Company was chartered and the following year acquired the Central Traction Company, Citizens Traction Company, Duquesne Traction Company and Pittsburgh Traction Company and converted them to electric operation. On July 27, 1896 the United Traction Company was chartered and absorbed the Second Avenue Traction Company, running electric cars since 1890; the Southern Traction Company acquired the lease of the West End Traction Company on October 1, 1900. Pittsburgh Railways was formed on January 1, 1902, when the Southern Traction Company acquired operating rights over the Consolidated Traction Company and United Traction Company; the new company operated 1,100 trolleys on 400 miles of track, with 178.7 million passengers and revenues of $6.7 million on the year. The lease and operate business model proved hard to support and the company declared bankruptcy twice, first in 1918 lasting for 6 years and again in 1938, this time lasting until January 1, 1951.
On July 26, 1936 Pittsburgh Railways took delivery of PCC streetcar No. 100 from the St. Louis Car Company, it was placed in the first revenue earning PCC in the world. Large scale abandonments of lines began in the late 1950s associated with highway or bridge work. In the 1960s a 92-mile automated guideway transit system was planned fanning out to the north, east and west including connections to both the Pittsburgh International Airport the Allegheny County Airport, Monroeville Mall and adjacent to Kennywood Amusement Park; the modern subway/light rail system can be traced to the abandonment of the proposed "Skybus" system in the mid-1970s, the subsequent $265 million federal grant on May 7, 1979, for construction of a downtown subway and modernization of suburban light rail. PAT, working with community representatives and government officials, undertook a detailed study on the future of the South Hills trolley lines, resolving to transform these valuable, high-density transit corridors into a modern LRT system.
The resulting Stage I LRT plan achieved a comprehensive reconstruction and upgrading of the 10.5-mile "main line" between downtown and the sub