www.sefindia.org

STRUCTURAL ENGINEERING FORUM OF INDIA [SEFI]

 Forum SubscriptionsSubscriptions DigestDigest Preferences   FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups  RegisterRegister FAQSecurity Tips FAQDonate
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log in to websiteLog in to websiteLog in to websiteLog in to forum 
Warning: Make sure you scan the downloaded attachment with updated antivirus tools  before opening them. They may contain viruses.
Use online scanners
here and here to upload downloaded attachment to check for safety.

The Eiffel Tower Story

 
Post new topicReply to topic Thank Post    www.sefindia.org Forum Index -> Engineering Marvels
View previous topic :: View next topic  
Author Message
admin
Site Admin
Site Admin


Joined: 21 Feb 2008
Posts: 540
Location: Phoenix Webtech Pvt. Ltd. Mumbai [

PostPosted: Sat Aug 04, 2012 3:43 am    Post subject: The Eiffel Tower Story Reply with quote

REVOLUTIONARY THINKING
In 1885, French officials began planning the Great Exposition of 1889, a celebration of the 100th anniversary of the French Revolution. They wanted to build some kind of monument that would be as glorious as France itself.
The Washington Monument, a masonry and marble obelisk, had recently been completed. At 557 feet high, it was the tallest building on earth. The French decided to top it by constructing a 1,000-foot-tall tower right in the heart of Paris.
Now all they had to do was find somebody who could design and build it.
OPEN SEASON
On May 2, 1886, the French government announced a design contest: French engineers and architects were invited to “study the possibility of erecting on the Champ de Mars an iron tower with a base of 125 meters square and 300 meters high.”
Whatever the contestants decided to propose, their designs had to meet two other criteria: 1) the structure had to be self-financing- it had to attract enough ticket-buying visitors to the exposition to pay for its own construction; and 2) it had to be a temporary structure that could be torn down easily at the end of the Exposition.
MERCI…BUT NON, MERCI
More than 100 proposals were submitted by the May 18 deadline. Most were fairly conventional, but some were downright weird. One person proposed building a huge guillotine; another suggested erecting a 1,000-foot-tall sprinkler to water all of Paris during droughts; a third suggested putting a huge electric light atop the tower that – with the help of strategically placed parabolic mirrors – would provide the entire city “eight times as much light as is necessary to read a newspaper.”
NO CONTEST
The truth was, none of them had a chance. By the time the contest was announced, Alexandre-Gustave Eiffel [wiki] – a 53-year-old structural engineer already considered France’s “master builder in metal” had the job sewn up. (He would later become as le Magicien du Fer – “the Iron Magician.”)
Weeks earlier, he had met with French minister Edouard Lockroy and presented plans for a wrought iron tower he was ready to build. Eiffel had already commissioned 5,329 mechanical drawings representing the 18,038 different components that would be used. Lockroy was so impressed that he rigged the contest so only Eiffel’s design would win.

Eiffel’s plan for the tower (Image Credit: L’histoire de la tour Eiffel et sa construction, vues par son architecte, un album publié en 1900)
JOINT VENTURE
In January 1887, Eiffel signed a contract with the French government and the City of Paris. Eiffel & Company, his engineering firm, agreed to contribute 1.3 million of the tower’s estimated $1.6 million construction cost. In exchange, Eiffel would receive all revenues generated by the tower during the exposition…and for 20 years afterward. (The government agreed to leave the tower up after the Exposition.) Afterward, full ownership reverted to the City of Paris. They could tear it down if they wanted.
MONEY MACHINE
Unlike other public monuments, the Eiffel Tower was designed to make money from the very beginning. If you wanted to take the elevator or the stairs to the first story, you had to pay 2 francs; going all the way to the top cost 5 francs (Sundays were cheaper). That was just the beginning; restaurants, cafes, and shops were planned for the first story; a post office, telegraph office, bakery, and printing press were planned for the second story. In all, the tower was designed to accommodate up to 10,416 paying customers at a time.
GROUNDBREAKING
Construction began on January 26, with not a moment to spare. With barely two years left to build the tower in time for opening of the Exposition, Eiffel would have to build the tower more quickly than any similar structure had been built before. The Washington Monument, just over half the Eiffel Tower’s size, had taken 36 years to complete.
PARISIAN PARTY POOPERS
A 1,000-foot tower would dwarf the Parisian skyline and overpower the city’s other landmarks, including Notre Dame, the Louvre, and Arc de Triomphe. When digging started on the foundation, more than 300 prominent Parisians signed a petition protesting the tower. They claimed that Eiffel’s “hallow candlestick” would “disfigure and dishonor” the city. But Eiffel and the city ignored the petition, and work continued uninterrupted.

Photos of Eiffel Tower construction (Image Credit: L’histoire de la tour Eiffel et sa construction, vues par son architecte, un album publié en 1900)
OTHER FEARS
The tower still had its critics. A French mathematics professor predicted that when the structure passed the 748-foot mark, it would inevitable collapse; another “expert” predicted that the tower’s lightening rods would kill all the fish in the Seine.
The Paris edition of the New York Herald claimed the tower was changing the weather; and the daily newspaper Le Matin ran a headline story claiming “The Tower is Sinking.” If it has really begun to sink,” Le Matin pontificated, “any further building should stop and sections already built should be demolished as quickly as possible.” As the tower’s progress continued unabated, however, a sense of awe began to replace the fear.
EIGHT WONDER OF THE WORLD


Most advances in architecture and engineering are incremental. If, for instance, you wanted to build the world’s first 10-story building, you’d expect to study the construction techniques of 8-and 9-story buildings first.
But Gustave Eiffel didn’t have that luxury. No one had ever built an iron tower like his of any size…let alone one that was twice as tall as the tallest building on earth.
AN ENGINEERING GENIUS
To accomplish his task, Eiffel devised some incredibly ingenious techniques:
• Unlike other massive engineering projects of the day, he had nearly all of the parts used in the tower prefabricated off-site in his workshops. This meant that when they arrived at the tower, the parts could quickly be riveted into place with a minimum of fuss.
• The rivet holes themselves were predrilled to a tolerance of one-tenth of one millimeter, making it possible for the twenty riveting teams to drive an average of 1,650 rivets a day.
• None of the girders used in the tower was permitted to weigh more than three tons. This made it possible to use smaller cranes to lift everything into place. As Joseph Harris writes in The Tallest Tower:

Eiffel had learned that using small components was faster and safer, even if his method did require more riveting, for cranes could be smaller and more mobile. The chances of accidents were reduced, and if one did occur the consequences were less serious. Use of bigger girders would have slowed the entire operation and required more expensive and complicated construction methods.
Thanks to these and other safety measures, the Eiffel Tower – the world’s tallest construction site – was also one of the safest. Of the hundreds of people who worked on the tower, only one, a riveter’s assistant named Dussardin, fell to his death.

THE PIERS
In the early days of the project, there were actually four construction sites at the Eiffel Tower, one for each foot, or “pier.” These piers did not join together until the 180-foot level…and once this point was reached, they had to be set perfectly level with one another to create a perfectly horizontal platform on which the remaining 800 feet of the tower could be built. If the piers were even slightly out of alignment, the tiniest discrepancy at the base of the tower would be magnified at the top: it would appear to lean.
Eiffel knew there was no way he could guarantee the piers would be vertical when finished – the margin for error was too great. So he installed temporary hydraulic pistons in the base of each of the feet. That way, as work on the tower progressed, he could “fine-tune” the entire tower into perfect alignment by slightly raising or lowering each foot. When the tower was properly aligned, workers could drive iron wedges into the piers to secure them permanently.
As it turned out, Eiffel had little to worry about. Even at the 180-foot level, the worst of the four massive piers was less than 2 ½ inches out of alignment. All four were easily adjusted and secured in place. Even today, the tower is perfectly vertical.


FINIS

The Eiffel Tower was a marvel- not just for its ingenuity of design, but also because it was completed ahead of schedule and under budget. The Exposition was scheduled to open on May 6; work on the tower was finished on March 31.
Eiffel & Company earned back it money in record time. During the six months of Exposition alone, the tower earned back more than $1.4 million of its $1.6 million construction cost; that combined with the $300,000 subsidy provided by the French government, pushed the tower into the black even before the Exposition closed.
The tower was such a magnificent structure that it won over many earlier critics. Among them was French prime minister Tirard. He had opposed the project at its inception, but awarded Eiffel the medal of the Legion of Honor after it was finished. The tower, a symbol of France’s unrivaled technical expertise, became the symbol of France itself.
Not everyone who hated the tower experienced a change of heart. Guy de Maupassant, the novelist best known for The Necklace, was said to eat regularly at a restaurant on the tower’s second floor. His reason: It was the only place in Paris where he was sure he wouldn’t see the tower. (Even some of the characters in his novels hated the tower.)




TOWER FACTS
• Every seven years, the Eiffel Tower receives a fresh coat of more than 300 tons of reddish-green paint. Why reddish-green? Because, tower officials say, it is the color that clashed least with the blue sky over Paris, and the green landscape of the Champ de Mars below.
• The positions of the Eiffel Tower’s four “feet” correspond to the “cardinal” points of a compass: they point exactly north, south, west, and east.
• In 1925 the City of Paris wanted to decorate the tower with electric lights as part of an arts exposition being held nearby, but the cost, estimated at $500,000, was too high. When automaker André Citroën learned of the project, he offered to pay for it himself…in exchange for the right to put his company name and corporate symbol in lights as well. The City agreed. “The Eiffel Tower,” Blake Ehrlich write in Paris on the Seine, “became the world’s largest electric sign, its outlines traced in lights.” The lights were so popular that the tower remained lit with various designs until 1937.
Franz Reichelt’s fatal jump: Link [YouTube]
• Sad fact: The Eiffel Tower is the most popular landmark for suicides in France. In an average year, four people commit suicide by jumping off the tower or, occasionally, by hanging themselves from its wrought iron beams. The first person killed in a jump from the tower, in 1911, was not an intentional suicide – the man was a tailor named Reichelt who had sewn himself a “spring-loaded bat-wing cape” that he thought would enable him to fly. It didn’t.


Interesting Sidelight
Gustave Eiffel also designed and built the iron skeleton that holds up the Statute of Liberty.
Room with a view: Among the amenities that Gustave Eiffel designed for the tower was a penthouse apartment at the top, complete with grand piano and spotlights for shining on other Paris monuments. He built it for his own use.

Eiffel Tower (Image Credit: altuwa [Flickr])
Source: http://www.neatorama.com/2007/07/16/the-eiffel-tower-story/
Back to top
View user's profile Send private message Visit poster's website AIM Address Yahoo Messenger MSN Messenger
Thankful People
1 user(s) is/are thankful for this post.
Display posts from previous:   
Post new topicReply to topic Thank Post    www.sefindia.org Forum Index -> Engineering Marvels All times are GMT
Page 1 of 1

 

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


© 2003, 2008 SEFINDIA, Indian Domain Registration
Publishing or acceptance of an advertisement is neither a guarantee nor endorsement of the advertiser's product or service. advertisement policy