The World Trade Centre Freedom Tower History Essay

The world trade centre was a building complex in lower Manhattan, New York whose seven buildings and a shopping concourse got destroyed by terrorist attack in September 2001. The world trade centre had been the largest commercial complex; it was the home to many businesses, government agencies and international trade organizations. The most famous and projecting structure among them was the Twin Towers, one rose to 1,362ft and the other to 1,368ft with floors almost an acre in size. The twin towers were not just ordinary buildings; they were the symbols of New York. The world trade centre was completed in 1973 and destroyed in 2001 now the site is currently being rebuilt with six new skyscrapers and a memorial to replace the twin towers which is formally known as the freedom tower for the casualties of the attack.

The original world trade centre was designed by Minoru Yamasaki and associates of Michigan. Minoru Yamasaki brought the idea of the two huge towers using a tube frame structural design. In order to gain approval for the project, the Ports Authority of New York and New Jersey agreed to take over the Hudson and Manhattan rail road which became the Ports Authority Trans-Hudson (PATH). The ground breaking of the world trade centre took place on the 5th of August in 1966. The North tower was completed in December 1970 and the South tower was completed in July 1971. The Twin Towers were the world tallest buildings for a short time before the completion of the Sears tower in Chicago in may 1973.

The complex was located in the heart of the New York City’s downtown financial district and contained 13.4 million square feet of office space. The windows on the World Trade Centre’s restaurant was located on the 106th and 107th floor of the north tower, while the top of the world observation deck was located on the 107th floor of the south tower. The world centre buildings includes the Marriott World Trade Centre, 4 World Trade Centre, 5 World Trade Centre, 6 World Trade Centre where the United States customs is located and the 7 World Trade Centre. The World Trade Centre has had at a lot of experiences. It once caught fire on February 13th, 1975 then bombing afterwards on February 26th, 1993 and terrorist attack on September 11th, 2001. The bombing destroyed some parts of the complex, killing 6 people and 50,000 workers and visitors were left gasping for air. Sheik Omar Abdel Rahman and nine other extremists were found guilty of the attack. In 1998, the Ports Authority decided to give the buildings to private companies to manage. The terrorist attack was on the 11th of September, 2001 were by hijackers flew two jets into the twin towers. The towers burnt for 56 minutes before the south tower collapsed followed by the north tower half an hour later. The terrorist attack killed 2750 people and more than 7000 people were injured. The remaining buildings were demolished due to the attack that caused them to be destroyed beyond repair. The site is currently being rebuilt consisting of a tower as a replacement for the twin towers as well as a memorial and other several office towers. After the completion of the Freedom tower, it is going to be the world tallest building of about 1776ft. The architect of the Freedom tower is Daniel Libeskind. Just like the former world trade centre, there will be a public lobby, two concourse levels which will have retail stores and provide access to mass transit for people, an indoor observation deck, a restaurant and an event space. There will also be a vertical memorial garden known as the Gardens of the World. The antenna on top of the spire will raise the tower to about 2000ft.

PLANNING AND CONSTRUCTION

The idea of building a World Trade Centre in New York was suggested in 1946. The New York State legislature passed a bill to the governor Thomas Dewey to develop plans for the project but the plans were held in 1949. In the late 1940s and 1950s, the growth of the economy was only concentrated in Midtown Manhattan while the Lower Manhattan was abandoned. Chas Manhattan Bank chairman David Rockefeller and his brother, the governor of New York Nelson Rockefeller insisted on the project that it would benefit the city. David Rockefeller suggested that the Port Authority build a World Trade Centre in Lower Manhattan and the plans were made public in 1961. The Ports Authority needed approval from both governors of New York and New Jersey so as to start the project.

20th of September 1962, the Ports Authority selected Minoru Yamasaki as the architect from several architects and Emery Roth & Sons as the associate architects. Yamasaki brought the idea of building two 110 storey towers so as to meet the Ports Authority requirement of building a 10 million square feet office space. He said the taller the buildings the more elevators needed to service the buildings so they decided to use a unique system by introducing sky lobbies where people could switch from large capacity express elevators to local elevators. This helped the elevators to be used efficiently.

After the demolition of the World Trade Centre, design contests were held for rebuilding the site and a memorial for the lives of people that were lost during the sorrowful events. Lower Manhattan Development Corporation was established by Governor Pataki in February 2003 to organize the various agencies and advisory committees concerned in the rebuilding efforts, chose architect Daniel Libeskind’s design work for rebuilding the site. His design included a memorial, vertical garden, a cultural centre and a Freedom tower but in July 2003, a new lead architect was brought named David Childs although Libeskind still remained in charge of the design of the site. Changes in the designing of the site were made which wind turbines were included in the spire of the freedom tower to generate 20% of the structure’s power. The Freedom Tower was likely to cost $1.5 Billion by the Ports Authority

New plans were released on June 29th 2005 for the construction of the site. The Freedom tower was to be moved backwards and also have the same size of cubic base as that of the twin towers. The wind turbines were removed and the spire will rise a bit more than 400ft likewise to maintain a maximum height of 1776ft. Michael Arad and Peter Walker were the architects who won the competition to design the memorial for the victims who lost their lives. The memorial and Reflecting Absence would respect the victims who died in the 1993 and 2001 terrorists attacks. The Reflecting Absence that will be built were the towers once stood, includes two pools where the names of the dead will be carved on the walls surrounded by leafy trees. The plans of the memorial were changed again in June 2006 to deal with security alarm, budgetary issues and say from the victims’ families. The pools will be kept and the names of the victims will be moved to the surrounding plaza above ground. Construction work began on the foundation in 2006 and ended in 2007. The slurry wall that disadvantaged the Hudson River during the attack on September 11th 2001 will be able to be viewed by visitors from the memorial. Santiago Calatrava was the architect who designed the Port Authority Trans-Hudson Transportation Hub which is likely to bring attractiveness, transport effectiveness to Manhattan and also to contain 250,000 walkers everyday which is the projected number of walkers in 2025. Five World Trade Centre office towers will be among the large part of the redevelopment of downtown Manhattan and will transform New York City’s skyline. They will consist of over 10 million square ft of office space just like that of the Twin Towers. Frank Grehry is the one in charge of the Performing Arts Center which will contain 1,000 seats and will be sited 60 ft away from the 1 World Trade Center ( Freedom Centre) on Fulton and Greenwich streets. The cost of the Performing Arts Centre was estimated to $500 Million. The modern dance Joyce Theatre will be featured there as well as the Tribecca Film Festival each and every spring. Construction of the Theatre will commence in 2010 or 2011.

After completion, Freedom tower is going to be the one of most valuable structures in the early 21st century. It is significant in stature, in design, in politics

BUILDING DETAILS

The twin towers had 110 floors in each tower with 97 elevators for visitors and workers while 6 elevators for carrying goods. It had 43,600 windows and 12,500 miles of electric cables. The structures weighed 500,000 tons having 200,000 tons of steel and 425,00 cubic yards of concrete. The twin towers even had its own zip code-10048. The tower was carried about 50,000 people both visitors and employees. It had 10 million square ft of office space as required by the Ports Authority with almost an acre of rentable space on each floor of both towers. The office spaces had no internal columns and the upper floors had 40,00 square ft per floor The towers had seven underground levels which had services, shopping area and a subway station which had both local and express stations. The 3 World Trade Centre had 22 floors, the 4 and 5 World Trade centre had 9 floors which had 500,000 square ft of floor area, 6 World Trade Centre had also had 500,000 square ft of floor area and a total number of 8 floors and the last but not the least, 7 World Trade Centre had 47 floors with 1,868,00 square ft of floor area.

The freedom tower is going to have 8 tall isosceles triangles meet at the centre end forming a prefect octagon. It is going to have an observation deck like the twin tower which ill b located at 1,362ft above the ground level and a glass parapet at 1,368 ft above the ground too. Architect Daniel Libeskind, the architect of the freedom towers and David child an architect of Larry Silberstein, the leaseholder of the World Trade Centre are working together to maximize the office space to meet that of the twin towers. The freedom towers will be 1,776 ft in height making it the new tallest building in the whole world after construction. The tower is going to have 70 floors and a spire which will raise it to its final height. The tower is going to have 2.6 million square ft of office space and tenant amenity spaces. Just like the twin towers it is going to have an observation deck, classy restaurants, retail stores, access to PATH subway and so much more. Many remnants of the World Trade Center in 2002, one of the symmetry is developed, including simple and more traditional is designed to withstand the existing New York skyline comparison of selected elements in the concept. There is precedent for a central spire from the drawings, such as the Empire State Building and the Chrysler Building (and the old World Trade Center towers as a thought) rather than off-center spire to echo the Statue of Liberty. 

According to David Childs, a new world trade competition, the project architect, has been discarded. 

Center: [15] 

Freedom Tower will be the symbol of the entire project and sign the memorial, which occupies the property of the New York City, a very important piece: the sky. We really hope that our design will be very real things, not only in sculpture based on the draft. We discussed the challenges of infrastructure, because the appropriate solution is to attention, not just beautiful.The design also has a great sculpture impact, we fully understand the importance of iconic tower, but it also must be a highly efficient building. Discourse on free tower is often limited to the symbolic, the formal and aesthetic Fangmian, but we recognize that without the operation of this building good if people do not wish to work, travel, and then we will Zuowei architect Shibai

STRUCTURAL DETAILS

Worthington, Skilling, Helle, and Jackon’s firm was the structural engineering firm that aided in improving Yamasaki’s tube frame structural design used for the twin towers. The Port Authority’s engineering department acted as the foundation engineers, Joseph R. Loring and associates as electrical engineers, Tishman Realty and construction company as the general contractors on the World Trade Centre project. The Ports Authority is an interstate agency, which during the construction period it was affected by the local laws and regulation of New York City. The structural engineers followed draft versions of the new 1968 building codes at the end. Fazlur Khan introduced the tube-frame design that was a new approach which allowed open floor plans rather than distributing columns throughout to support the structural loads as it had been done.

The World Trade Centre towers made good use of Vierendeel trusses: they are steel columns with high strength and load bearing perimeter. The Vierendeel trusses were closely packed together to form a strong rigid wall structure supporting all loads and sharing the gravity load with the core columns. The 59 column perimeter structure was built with large use of prefabricated modular pieces each consisting of 3 columns, 3 stories tall which were connected by spandrel plates. The spandrel plates were joint to columns in order to create the modular pieces at the fabrication shop. The modules lying next to each other were fastened together with the splices found at the mid span of the columns and spandrels. The spandrel plates were located at each floor, passing shear stress to columns, allowing them to work together in resisting lateral loads. The joints between modules were tied vertically so the column splices between adjacent modules were not at the same floor. The core is a combined steel and concrete structure that had an elevator and utility shafts, restrooms and so much more in each tower. It had an area of 87ft by 135 ft and it was also made up of 47 steel columns from the top of the tower to the bottom.

The floor construction is made up of assembled trussed steel which was 33 inches deep that rotated the full 60 ft to the core and also served as a diaphragm to harden the external walls against forces from wind load pressure. The floors spread out their wind loads round the external walls also providing lateral stability to the walls. The floor supported their own weight likewise live loads. The floors laid a 4 inch thick light weight concrete slab on steel deck likewise, the trusses supported the 4 inch concrete slab for composite actions. A grid of main trusses and light weight bridging trusses supported the floors. The trusses which were connected to the perimeter at alternate columns were on 2.03m center. The top chords of the trusses were joint with bolts to seats that were welded to the spandrels on the exterior sides and a channel welded on the interior side. The floors were connected to the perimeter spandrel plates with visco electric dampers which aided in reducing the amount of sway felt by people living in the building. Outrigger truss which is also known as Hat trusses located from the 107th floor to the top of the structures were made to support an antenna on top of each building structures. The north tower was the only tower that had an antenna which it was added in 1978 and was 110m tall. The trusses system had 6 trusses on the long axis and 4 along the short axis although it allowed some load redeployment between perimeter and the core columns likewise carried the transmission tower. All through the design process, wind tunnel test were carried out to start design wind pressures that the World Trade Centre will be expose to and the reaction of the buildings to those forces. Researches were also done to estimate how much sway inhabitants could be contented and healthy because some experienced wooziness and some other illnesses. One of the chief engineers Leslie Robertson worked together with another engineer to develop viscoelectirc dampers to suck up some of the sway. These viscoelecric dampers applied all over the structures at the joints between floor trusses and perimeter columns together with some other structural modifications reduced the sway to a suitable level.

One World Trade Center program includes 2.6 million square feet (241.000 sq. meters) of office space and an observation deck, world-class restaurant, parking and broadcast and antennae , all supported by both above and underground infrastructure engineering for the building and its neighbors in public spaces. Underground parking and occupant storage, shopping and way in to the PATH and subway trains and the World Financial Center are also made available. 

At 60 meters high (18 m) lobby topped by a chain of mechanical floors form a 200 square feet (61 m) base of the building. 69 tenant floors rise above the base at 1120 feet (341 m) above sea level, mechanical floors, restaurants and observation decks lead to an observation deck and glass parapet that mark 1362 feet (415 m) and 1368 feet (417 m), respectively – the heights of the original Twin Towers . An antenna structure held up by cables wrapped, designed by Schlaich Bergermann & Partner, stands at a height of 1776 feet (541 m), which is a representative of the year the U.S. Declaration of Independence was signed (July 4, 1776). 

The tower stands on a base cube whose square plan 200 feet by 200 feet (61 m by 61 m) will be almost as wide as 208 feet (63 m) Twin Towers. The base will be clad in more than 2,000 pieces of prismatic glass, each measuring 4 feet by 13 feet 4 inches (1.21 m by 4.06 m) with varying depths. It was designed to build on the subject matters of movement and light, a sparkling curtain of glass surface and base of the tower gives a dynamic smoothness of form whose appearance reflects its surroundings. Like the rest of the building, the base will serve as a beacon of light, glass facades Cable-net on all four sides of the building, again designed by Schlaich Bergermann, measures 60 feet (18 m) and high-end width of 30 feet (9 meters) on the east and west sides (for access to the observation deck and restaurant, respectively) at 50 feet (15 m) on the north side and 70 feet (21 meters) south of the main access tenant, activate the building at street level. 

As the tower itself rises from this cubic base, its square edges are chamfered back, transforming the square into eight tall isosceles triangles in elevation, or an elongated square antiprism in the middle, the tower forms a perfect octagon in plan and then ends in a glass parapet (elevation 1,362 feet (415 m) and 1368 feet (417 m)), whose plan is a square, rotated 45 degrees relative to the base. A mast having an antenna for television broadcasters designed by an association between SOM, artist Kenneth Snelson (who invented tensegrity structure), lighting designers and engineers, guaranteed by a system of cables, rises from a circular support ring, similar to the Statue of Liberty’s flame at a height of 1776 feet (541 m). The arrow is an intense beam of light that illuminates the night and will probably be visible on a thousand feet (305 m) in the air above the tower. 

new safety features include 3-foot (91 cm) thick reinforced concrete walls on all stairwells, elevator shafts, elevators and sprinkler systems; extremely wide emergency stairs, “” a dedicated set of stairwells for the exclusive use of firefighters and biological filters and chemicals throughout the ventilation system. The building will be over 25 feet (8 m) from West Street with the redesign and small base (the same width and length now that each of the previous rounds), 1 World Trade Center will average 90 feet (27 m) away from the street.  At its nearest point Street West will be 65 feet (20m). The windows on the side of the building facing this direction will be equipped with explosion-resistant plastic specially toughened, which will closely examine the same as the glass used in the other side of the building. 

Ultra-clear “glass, as opposed to reflective glass or tinted windows is proposed for the tower. This will benefit the propagation of the light house, at which point it is unclear how relevant the question of solar heat gain will be addressed. 1 World Trade Center will be green in many ways. Although the area of the roof of the tower is relatively limited, the building will be implementation of a rainwater collection and recycling. One World Trade Center is on track for a Gold certification for Leadership in Energy and Environmental Design . 

Its structure is designed around a period of high redundancy consists of steel beams and columns connected by a combination of welding and bolting. Paired with a core of concrete shear wall, the framework provides an important moment stiffness and idleness of the overall structure of the building while offering free column extends inside for maximum flexibility. 

As with all new facilities on the site of the World Trade Center, One World Trade Center will be heated by steam, with limited reserves of oil or gas utilities within the site. 

CONTROVERSIES

Plans to build the World Trade Center had been controversial. The site for the World Trade Center was the location of Radio Row, home to hundreds of commercial and industrial tenants, owners, small businesses and about 100 tenants, many of whom resisted forced relocation. A group of small businesses affected filed challenging an order by the port authority of eminent domain. The case made its way through court system to the United States Supreme Court, the Court refused to accept the case. 

Private real estate developers and members of the Real Estate Board of New York, led by Empire State Building owner Lawrence A. Wien, expressed concern about this much “subsidized” office space going on the open market, competing with the private sector when there was already plenty of vacancies. Others questioned whether the Port Authority ought to participate in a project described by some as a “wrong social priority”.

The World Trade Center design brought criticism of its aesthetics of the American Institute of Architects and other groups. Lewis Mumford, author of The City in History and other works on urban planning, disapprove of the project and other new skyscrapers and described as “just glass and metal filing cabinets.” The Twin Towers’ office windows narrow, only 18 inches (460 mm) wide, were hated by many for impairing the view from the buildings. 

The Trade Center “superblock” substituting a more traditional, dense neighborhood, was by some critics as an inhospitable environment that the complicated traffic network typical of Manhattan disrupted. For example, in his book The Pentagon of Power, Lewis Mumford criticized the center as an “example of the purposeless gigantism and technological exhibitionism that are now the living tissue evisceration of any major city.” On the other hand, Mr. Yamasaki saw the expanse as a focal point of calm amid the chaos of the city. 

For many years, the gigantic Austin J. Tobin Plaza unwelcoming and often beset by brisk winds at ground level. In 1999, the outdoor portion of the plaza reopened after undergoing $ 12-million reconstruction involved replacing pavers marble with gray and pink granite stones, adding new benches, planters, new restaurants, kiosks and food outdoor dining areas

The design of WTC 1 has arisen some controversy because of the limited number of floors in the previous draft that were designed and other Office-space facilities. The list of total office space throughout the rebuilt World Trade Center will be over 3 million square feet less than the old. The floor limit was imposed by Silverstein, who showed concern that a high floor would be another major terrorist attack liability. In subsequent redesign, the space occupying comparable Highest Became the World Trade Centre. After the destruction of the Twin Towers there was an unofficial movement to rebuild the two lost towers instead of building a tower. Developer Donald Trump has unveiled Also Twin design goal, he was not connected with the official project. The Twin design would bear a resemblance to the original Twin Towers, the buildings would be considerably larger to enhance security measures and would have large windows.

Ex New York Governor George Pataki was charged for alleged favoritism to gain influence with the winning architect’s bid was chosen as a favor to a close personal friend.

The base of the tower (reinforced by concerns about safety) is also a source of controversy. Some critics (particularly Deroy Murdock national review procedures) have suggested that it is alienating, and boring, and the feeling of fear reflects rather than freedom, leading them to the project “The Fear Tower.” Nicolai Ouroussoff, the architecture enemy for The New York Times, describes the tower base beautifications as a “grotesque attempt to disguise the underlying paranoia.” 

LIFE AND EVENTS

On a typical weekday 50,000 people worked in the towers with another 200,000 passing through as visitors.  The complex is so large that it had its own Zip code: 10048. The towers had expansive views from the observation deck on top of the South Tower and the Windows on the World restaurant on top of the North Tower. The Twin Towers became known worldwide, showing in numerous movies and TV shows like on postcards and other merchandise, and was seen as an icon of New York, in the same class as the Empire State Building, Chrysler Building and the Statue of Liberty.  

French high wire acrobatic performer Philippe Petit walked between the towers on a tightrope in 1974, as shown in the documentary film Man on Wire. Brooklyn toymaker George Willig scaled the south tower in 1977. 

In 1983, on Memorial Day, high-rise firefighting and rescue lawyer Dan Goodwin successfully climbed the outside of the WTO Center’sNorth Tower. His stunt was intended to draw attention to the possible inability of people trapped in upper floors of the skyscrapers to save. [84] [85] 

The World Chess Championship 1995 PCA was performed on the 107th floor of the South Tower. 

In January 1998, Mafia Ralph Guarino, who had won maintenance access to the World Trade Center, arranged a three-person crew on a heist in which more than 2 million U.S. dollars netted from an episode Brink’s on the eleventh floor of the World Trade Center .

February 13, 1975 fire 

On February 13, 1975, a three-alarm fire broke out on the 11th floor of the North Tower. Fire spread through the heart of the 9th and 14th floor ignited the insulation of telephone cables in a utility shaft that ran vertically between floors. Areas at the time of the fire was extinguished almost immediately and the initial fire was in a few hours. Most of the damage was concentrated on the 11th floor, fueled by cabinets filled with paper, alcohol-based solution for office and other office equipment. Fire protection of steel melting and there was no structural damage to the tower. Unlike the damage caused by fire, a few floors below suffered water damage from extinguishing the fires above. At that time, the World Trade Center had no sprinkler system.

The February 26, 1993 bombing 

Main article: 1993 World Trade Center bombing 

On February 26, 1993 at 12:17, a Ryder truck filled with 1500 pounds (680 kilograms) of explosives planted by Ramzi Yousef, exploded in the underground garage of the North Tower. The explosion opened a 100 foot (30 m) hole through five sublevel with the maximum damage that occurs at the level B1 and B2 and significant structural damage at level B3. Six people were slain and 50,000 other employees and visitors were gasping for air in the 110 story towers. Many people inside the North Tower were forced to walk down dark stairwells which contained no emergency lighting, some taking two hours or more to reach safety.