.jpg)
It is constructed of steel and concrete. Steel cables clad in 84 9-inch (229 mm) steel tubes (42 per pylon) along the center line of the bridge support the main span. It was designed by the Figg & Muller Engineering Group (who also designed the popular Seven Mile Bridge), and built by the American Bridge Company.
In 2005, an act of Florida Legislature officially named the current bridge the Bob Graham Sunshine Skyway Bridge, after the Governor of Florida and then U.S. Senator 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 Brotonne Bridge. The original bridge was dedicated to state engineer William E. Dean, as noted on a plaque displayed at the rest area at the south end 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.
Because of its height above the emerald-green Gulf waters, length of continuous travel, location in a warm-weather state, and modern architectural design, it is a popular spot for filming automobile commercials.
One of the major problems with the Sunshine Skyway Bridge is corrosion of the steel in the precast concrete segmental columns on the high level approaches. 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.Another problem arose around 2005–2006 when several news bureaus reported paint discolorations 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. In 2008, FDOT began an overhaul including repainting the cables in their entirety (instead of touching up) and rehabilitating the lighting system at the summit of the bridge.
The present bridge replaces a steel cantilever bridge of the same name. The original two-lane bridge built by the Virginia Bridge Company was opened to traffic on September 6, 1954,with a similar structure built parallel and to the west of it in 1969 to make it a four-lane bridge and bring it to Interstate standards. Opening of the newer span was delayed until 1971 for reinforcing of the south main pier, which had cracked due to insufficient supporting pile depth. The second span was used for all southbound traffic, while the original span was converted to carry northbound traffic.
The old bridge replaced a ferry from Point Pinellas to Piney Point. US 19 was extended from St. Petersburg to its current end north 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.
The original Sunshine Skyway Bridge was the site of a number of tragic events, including the collision of the US Coast Guard Cutter Blackthorn and inbound freighter Capricorn in 1980 which claimed 23 Coast Guardsmen's lives, and a structural collapse caused by a collision with the bridge support by the inbound freighter Summit Venture in 1980 which killed 35 people and ultimately ended the bridge spans' useful life.
On January 28, 1980, the 180 ft Iris class buoy tender USCGC Blackthorn was outbound from Tampa Bay, having just completed a total refit, as the 605 ft tanker Capricorn was inbound. Having just been overtaken by a brightly lit cruise ship, the Blackthorn had maneuvered into the center of the channel to allow the passenger ship to pass. As a consequence of the cruise ship's lights, the Blackthorn was unable to see the approaching Capricorn in the night's darkness. As the two ships approached, the Capricorn gave two short whistles to signal its intention to pass to starboard as the Blackthorn crowded the center of the channel.[disputed – discuss][citation needed] At some point, the Blackthorn, helmed by a junior officer, initiated evasive action but it was already too late. The two ships collided nearly head-on, with the anchor of the tanker imbedding itself in the hull plates of the cutter. At least 6 crewmen of the Blackthorn were trapped by the mangled metal skin of the ship. As the ships' momentum carried each other along, the anchor line of the tanker grew taut and pulled the Blackthorn over, capsizing the smaller ship and resulting in the drowning deaths of 23 crew trapped on board and below decks, approximately 3/4 of a mile from the Sunshine Skyway Bridge.
Following the accident, the Blackthorn was recovered and taken to drydock for postmortem analysis. Because it had been involved in a fatal accident, it was decided not to repair the vessel.[citation needed] She was stripped of her gear and had her mast and superstructure reduced. The hull was then towed offshore and intentionally sunk as an artificial reef.
The southbound span (opened in 1971) of the original bridge was destroyed at 7:33 a.m. on May 9, 1980, when the freighter MV Summit Venture collided with a pier (support column) during a blinding thunderstorm, sending over 1200 feet (366m) of the bridge plummeting into Tampa Bay. The collision caused six cars, a truck, and a Greyhound bus to fall 150 feet (46 m) into the water, killing 35 people.
.jpg)
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.
The pilot of the ship, John Lerro, was cleared of wrongdoing by both a state grand jury and a Coast Guard investigation
The south main pier (the one that required reinforcement before completion) withstood the ship strike without significant damage. It was the second pier to the south of it that was destroyed, a secondary pier that was not designed to withstand a large ship strike.[10]
After the Summit Venture disaster, the northbound span carried one lane in either direction until the current bridge opened. Before the old bridge was demolished and hauled away in barges, MacIntire (the only survivor in the collapse) was the last person to drive over it. He was accompanied by his wife, and when they reached the top of the bridge, they dropped 35 white carnations into the water, one for each person who died in the disaster.[17] 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.
Gov. 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 ships larger than the Summit Venture like tankers, container ships, and cruise ships.
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. 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 artificial 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 concrete and 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 and concrete piers.
After extensive research, the engineering team developed a 4 × 1: 16 ratio pulley system where each of the 4 corners of the span was connected to two 25 ton winches (bolted to the pavement of the deck). These winches controlled the descent of the main 360-foot (110 m), 608 ton span to a barge anchored 150 feet (46 m) below. As part of the project design, the engineering team developed a real time computerized, synchronized descent calculator and control program to help each of the two winch management teams ensure that all winches were synchronized at the same 30 feet (9.1 m) per minute descent rate. The operation was executed successfully in 21⁄2 hours despite adverse weather conditions.
Bridge suicides[edit]
According to compilations from various media reports as of 2009, at least 207 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 an estimated 34 others have tried, but survived. A Rottweiler named Shasta survived after either following or being carried over the edge by its owner, who died. Another 51 people ended their lives from the old Sunshine Skyway from 1954 to 1987. One man (23 year old Michael "Luciano" Plezia of Clevelandwas forced to jump at gunpoint in 1981, after having been kidnapped, beaten, tortured, and stabbed.; another, a 24 year old Sarasota carpenter, hanged himself from the bridge on Saturday morning, 4 July 1992. 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 high number of suicide attempts from the bridge, 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.However, the total number of jumpers has not significantly declined since the introduction of these safeguards.
On April 27, 1997, a group of amateur daredevils, led by a bartender from Ft. Lauderdale and composed of a mix of male and female participants, performed an unannounced guerrilla "pendulum swing" bungee jump off the bridge, wherein they planned to swing back and forth on a home-made bungee cord made of steel cable attached to the cast-off point. Arriving by stretch limousine, the group unexpectedly pulled over at the apex of the bridge, quickly rigged up their cable, tethered themselves to it with harnesses, and jumped over the edge. This stunt failed when the plastic sheathing on the steel cable, unable to handle the increase in gravitational forces exerted on it by the initial pendulum swing, sheared off and allowed the connecting clamps to slide freely off the cable, plunging the jumpers 60 feet (18 m) into the water, leading to broken bones and neck injuries. The entire accident was caught on multiple video cameras that had been set up to record the feat.
When later interviewed for a television video program, the group's leader stated that all of the components were rated to handle the combined weight of the participants, and, at the time, he thought the assembly was safe. Later studies showed that his design had failed to take into account the increased g-load caused by the pendulum action of the jump itself, exceeding the ratings on the components and leading to catastrophic failure of the structural integrity of the bungee cable. Since the accident, no other groups have attempted to perform a stunt jump from the bridge. This incident aired on Destroyed In Seconds on March 2, 2009.
In 2006, a feature film entitled Loren Cass was released, which depicted a suicide jump off the Sunshine Skyway.[29] Two years later, a second filmmaker, Sean Michael Davis of Rhino Productions, was inspired by his haunting experience witnessing a woman jump off the bridge so quickly that no one could intervene, to create a non-for-profit film titled Skyway Down. His objectives: to deter other potential jumpers by " 'punch[ing] them in the face' with interviews with survivors and family members",[30] to give them "hope and to try to de-glorify the romanticism of the bridge",in part by informing those who have "mulled a leap to know about the bloody, battered aftermath."
Corporal Gary Schluter of the Florida State Highway Patrol - who has "seen the number of suicides, and attempts, climb steadily over the last few years" at the Sunshine Skyway Bridge, as well as persuaded multiple would-be suicides at that site to live - advises: "People look at that water and think it's very serene, an easy way to die." But "it's more like hitting concrete." As he and other troopers explained to The New York Times reporter Rick Bragg, "Jumpers tend to die ugly. The fall, less than four seconds, ends in a bone-snapping, organ-rupturing trauma, but some jumpers do not lose consciousness, and drown in agony." Schluter elaborated: "We retrieve the bodies. They are distorted, mangled."
On October 12, 2009, a body was found in the trunk of a burning car on the Sunshine Skyway bridge. Witnesses saw a man carrying a gas can near the car. A Florida Highway Patrol trooper later saw the man jump from the bridge, to his death.[33] After an investigation, authorities deemed the deaths a murder-suicide. The jumper, Robert Cecil Laird, shot his ex-wife, Sheryl Laird (39), multiple times at her home in Lakeland before depositing her body in the vehicle's trunk and driving approximately 60 miles (97 km) to the bridge, where he set the car afire and jumped to his death.
Stopping on the bridge for any non-emergency (including sightseeing) is prohibited. As part of a controlled-access highway, pedestrians and bicycles are also prohibited. Traffic on the bridge is remotely monitored by the Florida Highway Patrol, and a stopped or illegal vehicle or a pedestrian will elicit a police dispatch.
No comments:
Post a Comment