| Zakim Bunker Hill Bridge | |
|---|---|
Zakim Bunker Hill Bridge |
|
| Official name | Leonard P Zakim-Bunker Hill Memorial Bridge |
| Carries | Interstate 93 and U.S. Route 1 |
| Crosses | Charles River, MBTA Orange Line |
| Locale | Boston, Massachusetts |
| Owner | Commonwealth of Massachusetts |
| Maintained by | Massachusetts Department of Transportation |
| Design | Hybrid Steel and Concrete Cable-stayed bridge[1] |
| Total length | 1,432 ft (436 m) |
| Width | 183 ft (56 m) |
| Height | 270 ft (82 m)[2] |
| Longest span | 745 ft (227 m) |
| Clearance below | 40 ft (12 m)[3] |
| Opened | March 30, 2003 (NB) December 20, 2003 (SB)[3] |
|
Leonard P. Zakim Bunker Hill Memorial Bridge (Massachusetts)
|
|
The Leonard P. Zakim Bunker Hill Memorial Bridge (or Zakim Bridge) is a cable-stayed bridge across the Charles River in Boston, Massachusetts. It is a replacement for the Charlestown High Bridge, an older truss bridge constructed in the 1950s, and is the world's widest cable-stayed bridge. Of 10 lanes, the main portion of the Zakim Bridge carries four lanes each way (northbound and southbound) of the Interstate 93 and U.S. Route 1 concurrency between the Thomas P. "Tip" O'Neill Jr. Tunnel and the elevated highway to the north. Two additional lanes are cantilevered outside the cables, which carry northbound traffic from the Sumner Tunnel and North End on-ramp. These lanes merge with the main highway north of the bridge. I-93 heads toward New Hampshire as the "Northern Expressway", and US 1 splits from the Interstate and travels northeast toward Massachusetts' north shore, crossing the Mystic River via the Tobin Bridge.
The bridge and connecting tunnel were built as part of the Big Dig, the largest highway construction project in the United States. The north-bound (NB) lanes were finished in March 2003, then south-bound (SB) lanes in December. The bridge's unique styling quickly became an icon for Boston, often featured in the backdrop of national news channels, to establish location, and included on tourist souvenirs. The bridge is commonly referred to as the "Zakim Bridge" or "Bunker Hill Bridge" by residents of nearby Charlestown.
The Leverett Circle Connector Bridge was constructed in conjunction with the Zakim Bridge, allowing some traffic to bypass it.
Contents |
In a cable-stayed bridge, instead of hanging the roadbed from cables slung between towers, the cables run directly between the roadbed and the towers. Although cable-stayed bridges have been common in Europe since World War II, they are relatively new to North America.
The bridge concept was developed by Swiss civil engineer Christian Menn and its design was engineered by American civil engineer Ruchu Hsu with Parsons Brinckerhoff. Boston-based architect Miguel Rosales was the lead architect/urban designer and facilitated community participation during the design process. Neither Hsu nor Rosales served as the designer of record for the project. The engineer of record is HNTB/FIGG. The lead designer from HNTB was Theodore Zoli; and W. Denney Pate from FIGG. The bridge follows a new design in which two outer lanes are cantilevered outside of the wires another eight lanes run through the towers. It has a striking, graceful appearance that is meant to echo the tower of the Bunker Hill Monument, which is within view of the bridge, and the white cables evoke imagery of the rigging of the USS Constitution.
The MBTA Orange Line tunnel lies beneath the bridge.
The bridge's full name commemorates both Boston civic leader and civil rights activist Leonard P. Zakim, who championed "building bridges between peoples",[4] and the Battle of Bunker Hill. Originally Massachusetts Governor A. Paul Cellucci sought to name it the "Freedom Bridge". In 2000, however, local clergy and religious leaders, including Cardinal Bernard Francis Law, requested the Zakim name shortly after Zakim's death from myeloma. Although Cellucci agreed to the naming, community leaders from Charlestown objected to the name as they felt that since the design reflected the nearby Bunker Hill memorial, it should be named the "Bunker Hill Freedom bridge". Allegations of antisemitism were leveled against members of the mostly white, Irish-Catholic community as reasons for resistance to the Zakim name, based on some comments quoted in the Boston Globe. In response, several community leaders spoke out against the allegations in a press conference, stating that the claims, made by Professor Jonathan Sarna, were his alone and not reflected in the Jewish community at large.[5]
Eventually a compromise between the Boston City Council, the Massachusetts State Legislature and community activists brought about the current name. As with the Hoover Dam, however, different communities will call the bridge by different colloquial names. Many people in the Charlestown area refer to it as the "Bunker Hill bridge", while most, including the local press and traffic monitoring services, refer to it as the "Zakim Bridge". Many Red Sox fans also refer to it as the "Buckner Bridge" because of the resemblance of the name Buckner to Bunker and because it appears cars pass unimpeded between a giant pair of legs, a reference to the famous 1986 World Series error.
At the time of the naming and sponsoring of the Boston Garden an article discussing appraisals of the other Boston landmarks suggested the probable amount that the naming of the bridge would have cost a sponsor would have been US$100,000,000.
On 14 October 2002, elephants from the Ringling Brothers and Barnum & Bailey Circus crossed the new Leonard P. Zakim Bunker Hill Memorial Bridge to demonstrate the bridge's structural integrity. The 14 elephants proved that the bridge supports 112,000 pounds. The Boston elephant march resembled tests of the 1800s when bridge engineering was more questionable. Elephants were used to demonstrate the sturdiness of the Eads Bridge in 1874 and the Brooklyn Bridge in 1884. According to folklore, elephants are used for such shows of strength because they are widely believed to have uncanny instincts and will not cross unsafe structures.[6]
|
||||||||
|
|||||||||||||||||||||||||||||||