Sunshine Skyway Bridge
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| Sunshine Skyway Bridge | |
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| Official name | The Bob Graham Sunshine Skyway Bridge |
| Carries | 4 general purpose lanes (I-275 and US 19) |
| Crosses | Tampa Bay |
| Locale | south of St. Petersburg and north of Terra Ceia, Florida |
| Maintained by | Florida Department of Transportation |
| ID number | 150189 |
| Design | continuous pre-stressed concrete cable-stayed bridge |
| Longest span | 365.8 meters (1200 feet) |
| Total length | 8851.392 meters (5.5 miles) |
| Width | 28.7 meters (94 feet) |
| Vertical clearance | 58.8 meters (193 feet) |
| Clearance below | 53.3 meters (175 feet) |
| AADT | 50,500[1][2][3] |
| Opening date | April 20, 1987 |
| Toll | $1 for passenger cars or $0.75 with SunPass |
| Maps and aerial photos | |
The Sunshine Skyway Bridge, spanning Florida's Tampa Bay, is the world's longest bridge with a cable-stayed main span, with a length of 29,040 feet (exactly 5.5 miles or approximately 8.85 km).[4] It is part of I-275 (SR 93) and US 19 (SR 55), connecting St. Petersburg in Pinellas County and Terra Ceia in Manatee County, Florida, passing through Hillsborough County waters. Construction of the current bridge began in 1982, and the completed bridge was dedicated on February 7, 1987. The new bridge cost $244 million to build, and was opened to traffic on April 20, 1987.
It is constructed of steel and concrete. Twenty-one steel cables clad in nine-inch steel tubes along the center line of the bridge support the structure. It was designed by the Figg & Muller Engineering Group, and built by the American Bridge Company.
In November 2005, an act of Florida Legislature officially named the current bridge the Bob Graham Sunshine Skyway Bridge, after the Governor of Florida who presided over its design and most of its construction. According to sources, he was inspired to suggest the current design by a visit to France, where he saw a similar cable-stayed bridge. The original bridge was dedicated to state engineer William E Dean, as noted on a plaque displayed at the south rest area of the bridge.
The Travel Channel rated the Sunshine Skyway #3 in its special on the "Top 10 Bridges" in the World. The bridge is considered the "flag bridge" of Florida.[5]
One of the major problems with the Sunshine Skyway Bridge is corrosion of the steel in the precast concrete segments. Because the segments are hollow, workers were able to enter the bridge superstructure in 2003 and 2004 to reinforce the corroded sections of the bridge, ensuring its future safety.[5] Another problem arose around 2005/2006 when several news bureaus uncovered peeling paint on the bridge's cables. These paint splotches and patches were a result of touch-ups that were performed over the years but began to show through over recent years. FDOT is currently performing an overhaul which will include repainting the cables in their entirety (instead of touching up), rehabilitating the lighting system at the summit of the bridge, as well as repainting the concrete retaining walls [1]
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[edit] The original Sunshine Skyway Bridge
The present bridge replaces a steel cantilever bridge of the same name. The original two-lane bridge was completed in 1954, with a similar structure built parallel to it in 1969 to make it a four-lane bridge and bring it to Interstate standards.
The old bridge replaced a ferry from Point Pinellas to Piney Point. US 19 was extended from St. Petersburg to its current end north of Palmetto when the bridge opened.
The original Sunshine Skyway Bridge is featured in the old-time radio series "Yours Truly, Johnny Dollar" in the episode "The Fancy Bridgework Matter" (11/22/1959) and in the original opening credits to the 1988 Superboy TV series which showed the hero flying over the damaged original span and then turning to view the new bridge under construction.
The remaining approaches to the old cantilever bridge remain in use as Skyway Fishing Pier State Park.
[edit] Bridge disaster
The southbound span of the original bridge (the one built in 1969) was destroyed on May 9, 1980, when the freighter MV Summit Venture collided with a pier (support column) during a storm, sending over 1200 feet (366m) of the bridge plummeting into Tampa Bay. The collision caused six automobiles and a Greyhound bus to fall 150 feet (46 m), killing 35 people.[6][7]
One man, Wesley MacIntire, survived the fall when his pickup truck landed on the deck of the Summit Venture before falling into the bay. He sued the company that owned the ship, and settled for $175,000 in 1984.[8] For the remaining nine years of his life until he died in 1989, MacIntire was haunted by the fact that he was the only one to survive the fall off the collapsing bridge. [9]
The pilot of the ship, John Lerro, was cleared of wrongdoing by both a state grand jury and a Coast Guard investigation. Although Lerro resumed his shipping duties soon afterward, he was forced to retire months later by the onset of multiple sclerosis,[10] dying from complications caused by the disease in 2002.
After the Summit Venture disaster, the northbound span carried one lane in either direction until the current bridge opened. The main span of the northbound bridge was demolished in 1993 and the approaches for both old spans were made into the Skyway Fishing Pier State Park. These approaches sit 1/2 mile (0.8 km) to the south and west of the current bridge.
Graham's idea for the design of the current bridge won out over other proposals, including a tunnel (deemed impractical due to Florida's high water table) and a simple reconstruction of the broken section of the old bridge that would not have improved shipping conditions. The new bridge's main span is 50% wider than the old bridge. The piers of the main span and the approaches for 1/4 mile (0.4 km) in either direction are surrounded by large concrete barriers called "dolphins" that can protect the bridge piers from collisions with freighters larger than the Summit Venture.[11]
[edit] Bridge suicides
According to compilations from various media reports, at least 96 people have committed suicide by jumping from the center span into the waters of Tampa Bay since the opening of the new bridge in 1987 and many more have tried.[12] Another 51 people ended their lives from the old Sunshine Skyway from 1954-1987. Several other missing persons are suspected of having jumped from the bridge, but their deaths could not be confirmed as no bodies were recovered.
In response to the bridge's popularity as method of demise for the depressed, the State of Florida installed six crisis hotline phones along the center span in 1999, and began 24-hour patrols. As of 2003, the call center received 18 calls from potential jumpers, all of whom survived, according to a St. Petersburg Times report.[13] However, the total number of jumpers has not significantly declined since the introduction of these safeguards.
On April 27, 1997 a group of daredevils did a "pendulum swing" off the bridge, where they were to go back and forth on a steel cable attached to the cast-off point, eventually ending up directly below where they had started. This failed when the plastic sheathing on the steel cable allowed the connecting clamps to slide freely off the cable, plunging them 60 feet into the water, leading to broken bones and neck injuries.[14] In 2006 a feature film entitled Loren Cass was released which depicted a suicide jump off the Sunshine Skyway.[15]
[edit] Old Bridge Demolition
In 1990 the Florida Department of Transportation awarded the winning bid to the Hardaway Company to demolish all steel and concrete sections of the Sunshine Skyway Bridge. in 1991 The Hardaway company formed the engineering and management team (George Brown project Manger and Jacob Apelbaum the Project Engineer) to begin the demolition work.
The scope of the project required that all underwater piles and piers, and surface roadway, girders, and beams be dismantled. Special care had to be taken in removing underwater bridge elements near the shipping channel. Additionally, the concrete material, deck sections, pilings and steel girders were to be collected in order to be placed offshore and along the remaining bridge approaches to become reefs for the new planned state fishing park. The main bridge span had to be removed in one piece in order not to block the main shipping canal leading to the port of Tampa.
During the disassembly work of the bridges’ structural steel members, several difficult engineering challenges had to be resolved: the order of disassembly, a safe method for detonating charges on steel members in a publicly open and difficult to control area such as the Tampa Bay, and the development of a safe methodology for the removal in one piece of the bridge’s main span.
After some extensive research, the engineering team developed a 4 x 1: 16 ratio pulley system where each of the 4 corners of the span was connected to two 25 ton winches (bolted to the deck of the pavement). These winches controlled the descent of the main 360 foot, 608 ton span to a barge anchored 150 feet below. As part of the solution, the engineering team developed a real time computerized, synchronized descent calculator and control program to help each of the two winch management teams insure that all winches were synchronized at the same 30 feet per minute descent rate. The solution was executed successfully in 2 1/2 hours despite adverse weather conditions.
As bridge disassembly work progressed, a number of environmental agencies discovered that the daily demolition activities (especially the underwater blasting of concrete piers and claiming of debris from the sea bottom) could seriously threaten protected marine mammals in the vicinity of the work. To address these issues, the engineering team developed bubble screens, underwater alarms systems, and confinement walls which were used extensively during the project. A true testament to the effectiveness of these devices was that during the entire demolition project none of the environmental agencies identified a single marine mammal casualty.
[edit] Gallery
[edit] Current Bridge
 The bridge at twilight |
 View of bridge from Fort De Soto Park's East Beach |
 Sunshine Skyway Bridge from South Pier rest area |
 Driving on the bridge, near the peak |
 View of bridge heading south |
 As seen from the water of Tampa Bay |
 View while driving across Sunshine Skyway Bridge |
[edit] Old Bridge demolition
 Demolition of concrete structure and slab - South access road |
 Demolition of concrete structure and slab - North access road |
 Demolition of steel and concrete girders |
 Main bridge span secure on barge being towed away |
 Blasting concrete piers |
 Blasting steel truss |
 Blasting steel truss |
[edit] Media Coverage
- Editorial (1991-9-7), “The Skyway is falling!”, ENR Engineering News Weekly: 13
- Editorial (1991-9-13), “The Sunshine Skyway Bridge - a History of Ups and Downs”, Dodge Construction Magazine: 5-6
- King, Robert (1991-9-25), “Chunk of Old Skyway Dismantled”, Herald-Tribune: 1B-3B
- Editorial (1991-9-13), “The Sunshine Skyway Bridge - a History of Ups and Downs”, Dodge Construction Magazine: 5-6
- Starnes, Sam (1991-9-25), “Origianl Skyway's main span removed”, The Bradenton Herald: A3-A6
[edit] References
- ^ Pinellas County Metropolitan Planning Organization. 2006 Average Annual Daily Traffic Counts in Pinellas County (A.A.D.T.) [map]. Retrieved on 2008-01-13.
- ^ Florida Department of Transportation. PTMS and TTMS Sites, 2006, Pinellas County (15) [map]. Retrieved on 2008-01-13.
- ^ 2006 Annual Average Daily Traffic Report Site 0088. Florida Department of Transportation. Retrieved on 2008-01-13.
- ^ Sunshine Skyway Bridge. Public Broadcasting Service. Retrieved on 2007-01-26.
- ^ a b Garcia, Jose. The Skyway Bridge - Yesterday, Today & Tomorrow (PDF). Florida Department of Transportaiton. Retrieved on 2007-03-18.
- ^ A blinding squall, then death. St. Petersburg Times. Retrieved on 2007-02-01.
- ^ Jean Heller. "The Day Skyway Fell: May 9, 1980", St. Petersburg Times, 2000-05-07. Retrieved on 2007-07-04.
- ^ "Suit in Bridge Fall Settlement", New York Times Archives, May 6, 1984. Retrieved on 2007-02-01.
- ^ Tampabay: Horrific accident created an unforgettable scene
- ^ Jean Heller. "Memories stay with man at command of the ship", St. Petersburg Times, 2000-05-07. Retrieved on 2007-07-04.
- ^ Building big: Databank: Sunshine Skyway Bridge. PBS Online. Retrieved on 2007-07-04.
- ^ The Skyway Bridge Jumper Pool. Retrieved on 2007-07-04.
- ^ Jones, Jamie. "Skyway safeguards don't deter jumpers", St. Petersburg Times, October 6, 2003. Retrieved on 2007-02-01.
- ^ O'Neil, Deborah. "Four hurt in Skyway stunt", St. Petersburg Times, April 28, 1997. Retrieved on 2007-03-18.
- ^ Wilson, Jon (October 11, 2006). Movie will have its first local viewing. St. Petersburg Times. Retrieved on 2007-05-28.
[edit] See also
- Skyway Fishing Pier State Park
- Millau Viaduct, France, a later, similar design
[edit] External links
- Sunshine Skyway Bridge page at Interstate275Florida.com
- "The Day The Skyway Fell", A special of the St. Petersburg Times on May 7, 2000
- "Video archives: 1980 Sunshine Skyway accident", A special section from WTVT-TV
- Work projects on the Sunshine Skyway Bridge
- Audio recording of Mayday call made from the Sunshine Skyway Bridge Collapse, Tampa Bay, Florida, May 1980 (MP3 format) (updated URI, Jun 29 2005)
- Sunshine Skyway in the Structurae database
- Sunshine Skyway Bridge (1987) in the Structurae database
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