Arthur Ravenel, Jr. Bridge
Encyclopedia
The Arthur Ravenel Jr. Bridge, also known as the New Cooper River Bridge, is a cable-stayed bridge
Cable-stayed bridge
A cable-stayed bridge is a bridge that consists of one or more columns , with cables supporting the bridge deck....

 over the Cooper River
Cooper River (South Carolina)
The Cooper River is a mainly tidal river in the U.S. state of South Carolina. These cities are located along the river, Mt. Pleasant, Charleston, North Charleston, Goose Creek and Hanahan. Short and wide, it is joined first by the blackwater East Branch, then farther downstream, the tidal Wando River...

 in South Carolina
South Carolina
South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...

, connecting downtown Charleston
Charleston, South Carolina
Charleston is the second largest city in the U.S. state of South Carolina. It was made the county seat of Charleston County in 1901 when Charleston County was founded. The city's original name was Charles Towne in 1670, and it moved to its present location from a location on the west bank of the...

 to Mount Pleasant
Mount Pleasant, South Carolina
Mount Pleasant is a large affluent suburban town in Charleston County, South Carolina, United States. It is a member of the Charleston–North Charleston–Summerville Metropolitan Statistical Area, for statistical purpose only, as designated by the U.S. Office of Management and Budget....

. The eight lane bridge satisfied the capacity of U.S. Route 17
U.S. Route 17 in South Carolina
In the U.S. state of South Carolina, U.S. Route 17 is a north–south highway located near the Atlantic Ocean. The route enters the state from Georgia at the Savannah River and serves Charleston and Myrtle Beach before entering North Carolina near Calabash.-Route description:US 17 enters into...

 when it opened in 2005 to replace two obsolete cantilever truss bridges. The bridge has a main span of 1,546 feet (471 m), the second longest among cable-stayed bridges in the Western Hemisphere
Western Hemisphere
The Western Hemisphere or western hemisphere is mainly used as a geographical term for the half of the Earth that lies west of the Prime Meridian and east of the Antimeridian , the other half being called the Eastern Hemisphere.In this sense, the western hemisphere consists of the western portions...

. It was built using the design-build
Design-Build
Design-build is a project delivery system used in the construction industry. It is a method to deliver a project in which the design and construction services are contracted by a single entity known as the design–builder or design–build contractor...

 method and was designed by Parsons Brinckerhoff
Parsons Brinckerhoff
Parsons Brinckerhoff is a professional services firm with 14,000 employees in 150 offices providing construction and operation management, planning, design, engineering, program management, strategic consulting, environmental and sustainability services for clients and communities in the Americas,...

.

History

The first bridge to cross the lower Cooper River opened in 1929, eventually named the John P. Grace Memorial Bridge
John P. Grace Memorial Bridge
The John P. Grace Memorial Bridge, or the Cooper River Bridge as it was familiarly known, was a cantilever bridge that crossed the Cooper River in Charleston, South Carolina. It opened on August 8, 1929 and was built by the Cooper River Bridge Company. Shortridge Hardesty of Waddell & Hardesty,...

 for former Charleston mayor John P. Grace, who spearheaded the project. The main span of the double cantilever truss bridge
Cantilever bridge
A cantilever bridge is a bridge built using cantilevers, 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...

 was the fifth longest in the world at 1,050 feet (320 m) and soared 150 feet (46 m) above the river. The main span of the second cantilever was the twelfth-longest in the world. The total length of the structure was about 2.7 miles (4.3 km). Following a 17 month construction at a cost of $6 million, it opened with a 3 day celebration that attracted visitors from around the globe. Engineers and critics proclaimed colorful descriptions of the unique structure, deeming it "the first roller-coaster bridge" and citing that "steep approaches, stupendous height, extremely narrow width, and a sharp curve at the dip conspire to excite and alarm the motorist." Privately owned originally, a 50-cent toll was charged for car and driver to cross. In 1943 the state of South Carolina purchased the bridge, and the tolls were lifted in 1946.

By the 1960s the Grace Memorial Bridge had become insufficient, with its two narrow 10-foot (3 m) lanes built for Ford Model A's and its steep grades of up to 6 percent. A new bridge was constructed alongside and parallel to it. Named for the then-South Carolina Highway Commissioner, the Silas N. Pearman Bridge opened in 1966 at cost of $15 million. Its three lanes, at a modern 12-foot (3.7 m) width, opened to northbound traffic while its older counterpart carried the southbound traffic into downtown Charleston. One lane was reversible on the Pearman bridge, which led to signs warning "Use lanes with green arrow" and "Do not use red X lane" on the bridge.

The two truss bridges had become functionally obsolete by 1979. Extensive metal deterioration caused by the lack of maintenance shortly after Grace Bridge's tolls were removed limited the capacity of the older Grace bridge to ten ton
Ton
The ton is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of weight, and as a unit of volume. It can also be used as a measure of energy, for truck classification, or as a colloquial term.It is derived from...

 vehicles (later five tons), and the reversible lane on the Pearman was eliminated (it had been able to switch to three lanes northbound for rush hour traffic), making that lane southbound permanently, diverting all heavy trucks, buses, and recreational vehicles to that lane on the Pearman bridge. Neither of the bridges had emergency lanes, and the Pearman bridge had no median between the northbound and southbound lanes because of its reversible lane, and it was not until 2002 when flexible barriers were added to the Pearman bridge to prevent head-on collisions.

Furthermore, the vertical clearance above the river – once among the highest in the world – could no longer accommodate modern shipping vessels. Three of Charleston’s four shipping terminals are situated up the Cooper and Wando
Wando River
The Wando River is a tidewater river in the coastal area of South Carolina. It begins in the town of Awendaw and empties into the Cooper River at Charleston Harbor. Its drainage area is . -External links:...

 Rivers, and the limited bridge clearance excluded the access of ships that would otherwise be beneficial to the economy of South Carolina. Now that the old bridges are disassembled, the world’s largest modern container ships are able to access all terminals of the nation's fourth-largest container port.

Funding

Raising financial support for a new eight-lane bridge over the Cooper River was a struggle 20 years in the making, prolonged by the state's insistence that it could not afford such a bridge and by Charleston's reluctance to provide any funds for the project. Several proposals were made for a toll bridge, but the mayors of Charleston and Mount Pleasant objected. When officials revealed in 1995 that the Grace Bridge scored a 4 out of 100 for safety and integrity, retired U.S. Congressman Arthur Ravenel, Jr.
Arthur Ravenel, Jr.
Arthur Ravenel, Jr. is a businessman and a Republican politician from Charleston, South Carolina.-Early life:The Charleston-born Ravenel served in the United States Marine Corps from 1945 to 1946. He thereafter received a bachelor of science degree from the College of Charleston in 1950. He is a...

 ran for the South Carolina Senate
South Carolina Senate
The South Carolina Senate is the upper house of the South Carolina General Assembly, the lower house being the South Carolina House of Representatives...

 with a goal of solving the funding problem. He helped to establish the S.C. Infrastructure Bank and worked with local, state, and federal officials to create partnerships that helped to materialize the final funding.

The State Infrastructure Bank (SIB) budgeted $325 million to accompany $96.6 million from the Federal Highway Administration
Federal Highway Administration
The Federal Highway Administration is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two "programs," the Federal-aid Highway Program and the Federal Lands Highway Program...

. The project did not become a reality, however, until the SIB agreed to commit to a $215 million federal loan, provided that Charleston County
Charleston County, South Carolina
Charleston County is a county located in the U.S. state of South Carolina. According to a 2005 U.S. Census Bureau estimate, its population was 330,368. Its county seat is Charleston. It is the third-most populous county in the state . Charleston County was created in 1901 by an act of the South...

 would contribute $3 million a year for 25 years, including an 8.33% sales tax increase, to the federal loan, as well as yearly payments from the SCDOT and State Ports Authority. The overall price of the bridge totaled around $700 million.

Design

Charleston’s new bridge over the Cooper River is a cable-stayed
Cable-stayed bridge
A cable-stayed bridge is a bridge that consists of one or more columns , with cables supporting the bridge deck....

 suspension design with two diamond-shaped towers, each soaring to a height of 575 feet (175 m). The total length of the structure is 13,200 feet (4.0 km), with the main span stretching 1,546 feet (471 m) between the towers. 128 individual cables anchored to the inside of the diamond towers suspend the deck 186 feet (57 m) above the river. The roadway consists of eight 12-foot (3.7 m) lanes, four in each direction. A campaign by locals eventually led to the addition of a 12 feet (3.7 m) bicycle and pedestrian path to the design, which runs along the entire south edge of the bridge overlooking Charleston Harbor and the Atlantic Ocean.

The bridge superstructure is designed to withstand shipping accidents and the natural disasters that have plagued Charleston’s history. The span is designed to endure wind gusts in excess of 300 mph (480 km/h), far stronger than those of the worst storm in Charleston's history, Hurricane Hugo
Hurricane Hugo
Hurricane Hugo was a classical, destructive and rare Cape Verde-type hurricane which struck the Caribbean islands of Guadeloupe, Montserrat, St. Croix, Puerto Rico and the USA mainland in South Carolina as a Category 4 hurricane during September of the 1989 Atlantic hurricane season...

 in 1989. Engineers also had to be mindful of the 1886 earthquake
Charleston earthquake
The Charleston Earthquake of 1886 was a powerful intraplate earthquake that hit the area of Charleston, South Carolina. After the 1811 and 1812 quakes in New Madrid, Missouri, it is one of the most powerful and damaging quakes to hit the southeastern United States. The shaking occurred at 9:50 p.m....

 that nearly leveled Charleston. The Ravenel Bridge is designed to withstand an earthquake to approximately 7.4 on the Richter scale without total failure. To protect the bridge from uncontrolled ships, the towers are flanked by one-acre rock islands. Any ship will run aground on the islands before it can collide with the towers.

The bridge includes a shared bicycle-pedestrian path named Wonders' Way in memory of Garrett Wonders. Wonders was a US Navy ensign stationed in Charleston and was in training for the 2004 Olympics before he died in a bicycle-vehicle collision. The path was included in design of the new bridge because of grassroots efforts by groups such as a fifth grade class at a local elementary school.

Construction

Groundbreaking on the bridge occurred in 2001 in Mount Pleasant. The bridge was built as a design-build
Design-Build
Design-build is a project delivery system used in the construction industry. It is a method to deliver a project in which the design and construction services are contracted by a single entity known as the design–builder or design–build contractor...

 project, meaning that one contract was signed to both design and construct the bridge. This meant that construction could begin even while the design was not yet finalized. The bridge was built by a joint venture
Joint venture
A joint venture is a business agreement in which parties agree to develop, for a finite time, a new entity and new assets by contributing equity. They exercise control over the enterprise and consequently share revenues, expenses and assets...

 of two major construction firms operating under the name Palmetto Bridge Constructors. The joint venture partners were Tidewater Skanska
Skanska
Skanska AB, is a multinational construction and development company based in Sweden, where it also is the largest construction company. The company's head office is in Solna, north of Stockholm.-History:...

 of Norfolk, Virginia
Norfolk, Virginia
Norfolk is an independent city in the Commonwealth of Virginia in the United States. With a population of 242,803 as of the 2010 Census, it is Virginia's second-largest city behind neighboring Virginia Beach....

 and Flatiron Constructors of Longmont, Colorado
Longmont, Colorado
Longmont is a Home Rule Municipality in Boulder and Weld counties in the U.S. state of Colorado. Longmont is located in Northern Colorado. Longmont is the 13th most populous city in the State of Colorado. The word "Longmont" comes from Longs Peak, a prominent mountain named for explorer Stephen H....

. The construction joint venture hired Parsons Brinckerhoff
Parsons Brinckerhoff
Parsons Brinckerhoff is a professional services firm with 14,000 employees in 150 offices providing construction and operation management, planning, design, engineering, program management, strategic consulting, environmental and sustainability services for clients and communities in the Americas,...

 to complete the design. For the sake of simplifying labor and equipment resources, Palmetto Bridge Constructors actually managed the building of the bridge as five separate projects (the two highway interchanges at either end of the bridge, the two approach spans, and the cable-stayed span) going on simultaneously.

By the summer of 2002 the foundations for the towers and most of the piers were in place and the rock islands were completed. The steel and concrete towers began to ascend from the islands soon after. Originally, each of the towers was to be topped with a 50 feet (15.2 m) multicolored LED "beacon," but public opinion caused this plan to be scrapped.

The fast-paced construction schedule led to contractors to use a self-climbing form system to build the towers. The formwork, supplied by PERI
Peri
In Persian mythology, which constitutes the mythology of not just Persians but all Iranian peoples, peris are descended from fallen angels who have been denied paradise until they have done penance. In earlier sources they are described as agents of evil; later, they are benevolent...

, provided a solution to meet the tight construction tolerances and provide safe access for workers laboring hundreds of feet in the air. The self-climbing system meant that the tower cranes did not have to spend time raising the forms after each segment of concrete hardened, and instead could be better used to haul material from barges below.

The first cables were hung from the towers in 2004—as a time-saving measure, this was done before the towers were wholly completed. Sections of the deck were built outward from each of the towers as more cables were hung.

The decks of the approaches were taking shape as well. Construction of part of the roadway actually occurred over the top of the old cantilever bridges, which remained open to traffic without interruption.

A ceremony was held in March 2005, when the last slab of the deck was added, thus making the bridge "complete." But paving, installation of lights and signs, and cleanup meant that the bridge would not open for another four months.

Following a week-long celebration that included a public bridge walk, concerts, dinners, and fireworks, the bridge was dedicated and opened on July 16, 2005 – one year ahead of schedule and under budget. The bridge was featured on the TV show Extreme Engineering
Extreme Engineering
Extreme Engineering is a documentary television series that airs on the Discovery Channel and the Science Channel. The program features futuristic and ongoing engineering projects. As of April 2011, the show is airing its ninth season. Danny Forster first hosted the series in season 4 and has been...

.

Bridge Run

The bridge is home to the annual USA Track & Field 10,000 meter Cooper River Bridge Run
Cooper River Bridge Run
The Cooper River Bridge Run is an annual one-way road running event held in the cities of Mount Pleasant and Charleston in South Carolina, on the first Saturday in April, unless it is the day before Easter Sunday, when the event is held on the last Saturday in March...

 on the first weekend of April. This event attracts up to 50,000 people. The route starts in Mount Pleasant
Mount Pleasant, South Carolina
Mount Pleasant is a large affluent suburban town in Charleston County, South Carolina, United States. It is a member of the Charleston–North Charleston–Summerville Metropolitan Statistical Area, for statistical purpose only, as designated by the U.S. Office of Management and Budget....

 and finishes in downtown Charleston at Marion Square.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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