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Tuesday, September 17, 2019

History of The Mackinac Bridge

Since Nov. 1, 1957, when the Mackinac Bridge opened to public traffic, the iconic symbol has stood as solemn testimony to mankind's engineering abilities. The Mackinac Bridge is made up of more than one million tons of concrete and steel. Its towers rise 552 feet above the Straits of Mackinac and reach 210 feet below the waves. From May 7, 1954, until late fall of 1957, about 3,500 laborers worked in and over the Straits of Mackinac constructing the bridge. The project cost the lives of 5 men. In addition, 7,500 people labored in offsite job shops and quarries from Duluth, Minn., to Pittsburgh, welding, forging and assembling steel, mining rock and mixing concrete. There was a total of 85,000 blueprints printed for the construction of the Mackinac Bridge.Construction began on the bridge on May 7, 1954, following years of debate on how to best cross the Straits of Mackinac. Everything from a tunnel to a series of causeways, tunnels and bridges going from Cheboygan to Bois Blanc Island to Round Island to Mackinac Island finally ending in St. Ignace- before a single suspension bridge with two towers was ultimately chosen. This was made possible because of Steinman's experience with other bridge projects, with it prompted him to encourage private financing for the Mackinac Bridge. The bridge was financed through a unique bond sale that covered its $100 million cost without using state or public funding. The bonds sold to pay for the Mackinac Bridge were retired July 1, 1986. To anchor the 100 million gross tons of the Mackinac Bridge, man-made mountains were required to be built in 88 feet of water. The anchor blocks- piers 17 and 22-were to become the beginning and end of the world's longest suspended span to date. The harbor at St. Ignace became the home base for Merritt-Chapman and Scott's marine construction equipment, regarded in 1954 as the largest gathering of its type ever assembled for a civilian project. St. Ignace was the location for land-based construction of the giant steel foundations and bridge support pieces. Decompression sickness, or â€Å"the bends,† was a constant threat to the safety of the divers who worked in the extremely cold, deep water of the straits. Commonly told among school children an ironworker who lost his footing fell to his death. It's said he landed in newly poured concrete, where his body lies today, preserved beneath the bride connecting the two peninsulas of Michigan. While historians say no iron, worker is encased in concrete, five people did die in accidents related to construction of the bridge. One died when he surfaced too quickly, a welder died when he fell into an underwater retaining structure, a worker fell from a short distance into the water and drowned, and two others fell 550 feet from a catwalk near the North tower, according to the authorities. Of the two workers who fell from the catwalk, one body was recovers immediately and the other was never found. Mackinac Bridge workers, like many workers involved in an intense high-stakes project, enjoyed a special camaraderie that they still speak of today. There was a feeling of togetherness, of them all being in the same situation, and of beating the odds. There was also a concern for each-others safety and welfare, with many of the men becoming lifelong friends. A new record for underwater consolidation of concrete was set in the spring of 1955, when work resumed after a long winter of ice and snow. During the 31 days of May that year, 103,000 cubic yards of concrete were poured into foundations of the Mackinac Bridge. A final step before the cables were encased in a protective piping was a coat the wire in a corrosive-resistant, â€Å"red-lead† paste. This was done to protect against rust and corrosion, two factors which could seriously compromise the integrity of the suspension system. The coating was a terrific success, as annual inspections done by removing the piping reveal little to no damage done by the forces of nature. Besides the main suspension span, the Mackinac Bridge is really constructed of a series of smaller, conventional bridges that would span many wide, formidable rivers and gorges. The building of these linked spans took place for the most part on land. All the work was done within sight of ferryboat passengers, crossing for the last 35-minute trips before they would be able to drive across the new route in less than 10 minutes. Michigan's miracle Bridge was becoming a reality. Workers were issued a safety helmet complete with miner's light and a life jacket for the boat trip out to the job site. Beyond that, all they took along was their lunch. The men would then leave the lifejackets on board for the next crew, disregarding the fact that they were working around very deep water that could be extremely cold. The general highway approach to the bridge was being formed at Mackinaw City, where a viaduct took the highway over the villages main street, Central Avenue. The date was July 22, 1957, and inclement weather delayed the raising of the final piece of Dr. David B. Steinman's geometric puzzle to conquer the Straits of Mackinac. That evening, the last section was raised and bolted into place, connecting the steel of a bridge that would tie Michigan together as a state. All suspension bridges are designed to move to accommodate wind, temperature change, and weight. Thanks to the open grating installed on the middle two lanes of the Mackinac Bridge, the design flexes easily when necessary. Wind water and snow easily passes through the grates surface. The completed tollbooth and administration building were readied just in time for occupancy before the Mackinac Bridge opened for business. The last job to get the Mackinac Bridge ready for traffic was to coat the concrete traffic lanes with a layer of bituminous asphalt, completed only days before the official opening. Tolls have always been a staple of the bridge to offset the costs of construction and maintenance. Opened on Nov. 1, 1957, tolls were set at $3.25 per passenger vehicle. In 1961, tolls rose to 3.50 and again to $3.75, where they stayed until 1969, when the Legislature passed funding for the authority and tolls were lowered to $1.50 for a passenger vehicle. The cost for traversing the bridge remained at $1.50 until 2005, when it was raised to $2.50, because of increased maintenance costs, Sweeney said. The Mackinac bridge is the third-longest suspension bridge in the world behind the Akashi Kaikyo Bridge in Japan at 12,826 feet between suspensions and the Great Belt Bridge in Denmark at 8,921 feet. Both bridges opened in 1998. At 8,614 feet between suspensions, the Mackinac Bridge is the longest suspension bridge in the Western Hemisphere. The total length of the Bridge 28,372 feet. It links Mackinac City in the Lower Peninsula. At just over five miles, the bridge is long enough to cause some trouble for crossing motorists who fail to fill up their gas tanks before crossing. To keep the bridge looking pristine, workers spend countless hours and use myriad gallons of paint. â€Å"Every year we use around 50,000 gallons for spot painting,† said Sweeney. Of the paint used each year, 45,000 gallons of green is used on the lower sections and cables, while 5,000 of ivory is used on the structures. Because of an $80 million maintenance plan, the 50-year-old structure is expected to have an infinite lifespan. Overhead highway lighting was installed to make nighttime crossings of the bridge safe and enjoyable. The bridge lighting could be seen for miles from either the Mackinaw City or St. Ignace shores, and cable lighting provided a further distinctive accent. One thing that bridge workers did not do before the bridge opened was paint it. The construction schedule dictated a November opening, and painters needed warmer temperatures before they could begin the big job of painting such a large structure.On November 1, 1957, traffic officially opened on the Mackinac Bridge. A huge story, the event attracted 150 newspaper men from throughout Michigan and neighboring states that included Wisconsin, Illinois, Ohio, Indiana, New York, and Ontario. Only a comparative few of the thousands of people attending the celebration were able to watch the dedication of the Mackinac Bridge, held at pier 22, the north anchor block of the bridge, on June 28, 1958. It was there that a five-mile length of ribbon was stretched from Mackinaw City at the south end and from the St. Ignace shore to the north. The Mackinac Bridge began celebrating the first year it was open by offering the public a chance to walk across the span. The event started as a race-walking activity, but soon became popular with thousands who wanted to return the following year and bring their friends with them. On May 9, 2003, the highest wind speed ever recorded on the bridge occurred at 4:08 p.m. The anemometer read 124 miles per hour.Area: Bridge sparks questions, myths. Keywords used to find article: News paper articles on Mackinac Bridge. Found at the local library. Published in Lansing. Authors are Michael Carney and Capital News Service. It was published Monday, February 26th, 2007. The purpose this source serves for my topic. Gives important dates such as when construction started on the bridge, also goes into detail about the tolls and amounts for crossing the bridge. Michael Carney writes about the work of the Mackinac Bridge. The structure of the document would be an informative news paper article. Works Cited: Carney, Michael. â€Å"Area Bridge Sparks Questions, Myths.† The Mining Journal [Lansing] 26 Feb. 2007: 3A. Print. Images of America Mackinac Bridge. Keywords used to find book: History of the Mackinac Bridge. Found at Public Library. Published by Arcadia Publishing Charleston SC, Chicago IL; Portsmouth NH, San Francisco CA. Author Mike Fornes. Published in 2007. The purpose this source serves me is it gives me the history for both the bridge and everyone who helped to build it. Works Cited: Fornes, Mike. Mackinac Bridge. Charleston, SC: Arcadia, 2007. Print. Area: Model Marks ‘Big Mac's' 50th year. Looked up News paper articles on the Mackinac Bridge at the local library. Published in Farwell. I could not find an Author. Published in 2007. The information I pulled from this source help make my introduction to my essay with just enough to get the reader to question what all I was going to go into detail about. Works Cited: â€Å"Area Model Marks ‘Big Mac's' 50th year.† The Mining Journal [Farwell] 28 May. 2007: 3A. Print.

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