Construction of One World Trade Center explained

One World Trade Center is the main building of the rebuilt World Trade Center complex in Lower Manhattan, New York City. Construction of One World Trade Center was deferred until 2006 because of disputes between the Port Authority of New York and New Jersey and the developer. Tishman Realty & Construction[1] is the selected builder. The building reached ground level on May 17, 2008, and was topped out on May 10, 2013. One World Trade Center opened to tenants on November 3, 2014, and One World Observatory opened to the public on May 28, 2015.[2]

2004–2007

One World Trade Center is considered the first major building whose construction is based upon a three-dimensional Building Information Model.[3] The symbolic cornerstone of One World Trade Center was laid down in a ceremony on July 4, 2004,[4] but further construction of the tower was stalled until 2006. The cornerstone was temporarily removed from the site on June 23, 2006.[5] The project was delayed due to disputes over money, security and design but the last major issues were resolved on April 26, 2006 with a deal between developer Larry Silverstein and the Port Authority of New York and New Jersey. During the summer of 2006, explosives were detonated at the World Trade Center construction site, testing the use of charges to clear bedrock for the building's foundation. Controlled explosions continued for approximately two months thereafter.

On November 18, 2006, 400abbr=offNaNabbr=off of concrete were poured onto the foundation of the One World Trade Center, carried by as many as 40 trucks. On December 17, 2006, a ceremony was held in Battery Park City, with the public invited to sign a 30feet steel beam.[6] This beam, the first to be installed, was welded onto the building's base on December 19, 2006.[7]

On January 9, 2007, a second set of beams was welded to the top of the first set. February 2007 estimates put the cost for construction of 1 WTC at $3 billion, or $1,150 per square foot ($12,380 per square meter). Approximately $1 billion of insurance money recouped by Silverstein in connection with the September 11 attacks is being used for construction of the new One World Trade Center.[8] The State of New York is expected to provide $250 million toward construction costs, and the Port Authority agreed to finance another $1 billion through bonds.[9] In 2007, Tishman Construction Corporation of New York completed a row of steel columns at the perimeter of the construction site. Two tower crane bases were erected, each base containing a functioning luffing-jib tower crane. By the end of 2007, the tower's footings and foundations were nearly complete.[10]

2008

In January 2008, two construction cranes were moved into the construction site. The tower's concrete core began rising in the first months of 2008. By February 22, 2008, 9,400 of the nearly 50000ST of steel necessary had been ordered.[11] By March 13, 2008, the steel for the tower had reached 70feet high, 10feet below street level.[12] [13] From late March through early April, a 400NaN0 tall mockup of a section of the tower's wall with twenty-four windows was tested by Construction Consulting Laboratory West in Ontario, California. The purpose of the testing was to ensure that the all-glass exterior of the tower will be able to withstand earthquakes and extreme weather conditions.[14] Testing also took place on another full-scale mockup south of Albuquerque, New Mexico. Both mockups passed the tests.[15] In mid-April, a batch of concrete had to be replaced after it failed a stress test.[16]

On May 17, 2008, the tower's steel reached street level when new sections were bolted to two of the twenty-four jumbo steel columns marking the building's footprint. The new column sections brought the height of the structure up to 15feet above street level.[17] In June, the chamfered steel skeleton of the tower's concrete base had begun to take shape.[18] By the end of the month, the concrete had been poured for the floor of the tower's basement level B3.[19] In his June 30, 2008 World Trade Center Rebuilding Assessment to the then New York Governor David Paterson, Port Authority executive director Christopher O. Ward noted that roughly 90 percent of the construction contracts had been bid.[20]

By August, 1 WTC had reached 25feet above street level.[21] During its September 16 meeting, the Port Authority board approved contracts for security and building management systems,[22] and 95% of the contracts needed to complete the tower had been signed.[23] The $20 million security contract includes sophisticated video analysis in which computers would alert security personnel to abnormal situations automatically.[24] On October 10, Collavino Construction poured an additional 520cuyd of concrete for the tower's concrete core, raising it to just above street level.[25]

2009

By February 11, 2009, the tower was 105feet above street level.[26] On July 2, 2009, over 1200cuyd of concrete were poured to form parts of the street-level plaza. On August 13, the builders of 1 WTC set a 70ST piece of steel into place—the largest column installed yet at the building. Each steel column, made at a factory in Luxembourg, was about 60feet long. The columns at the bottom of the tower's foundation were about 35feet long.[27]

By November 1, 2009, the twenty-four perimeter columns of 1 WTC were all erected, and construction of the second floor (the first floor above ground level) was nearly complete. In addition, The Port Authority of New York and New Jersey reported in their 2009 Q3 Annual Report that steel erection should commence by January 2010, and that the typical floor construction could begin.[28]

2010

Steel and concrete installation continued in 2010, where two cranes were on site. The fifth floor was finished on January 16. In February, construction began on the sixth floor, the last floor of 1 WTC's base, and the Port Authority announced that the tower's steel superstructure had reached 200feet above street level.[29] By the end of March 2010, steel beams began to be erected for the second office floor. In April, the 45-degree octagon was installed, the building's steel frame had reached 26 floors, and concrete was completed on the base structure in the latter part of the month.[30]

In May 2010, the Port Authority stated that they were building close to one floor per week, and was projected that One World Trade Center would reach 55 stories by the end of 2010.[31] The cocoon system was also installed, marking the first time a cocoon safety system has been installed on a steel superstructure in the city.[32]

On July 13, 2010, workers found remains of an 18th-century sailing ship at the World Trade Center site while excavating for the underground Vehicle Security Center for One World Trade Center.[33] The remains of a 32feet section of the ship's hull and a 100lb anchor were found. The hull had been truncated and the beams sawed.[34] The ship was likely used as landfill material during the early 19th century to help expand Manhattan. Timbers from the ship were removed and sent to a laboratory to try to date the vessel.[35] An additional section of the ship was found on the site in August 2011, giving historians more information about the vessel, which was active around the 1770s.[36] [37]

By October 2010, the tower's steel superstructure reached 44 stories.[38] [39] In November, stainless steel and glass facade panels were being prepared for later installation, with the panels scheduled to be assembled between the 20th and 24th floors.[40] On November 13, the first glass facade panels were installed on the 20th floor. Steven Coleman, spokesman for the Port Authority, stated, "Once they get rolling, they'll be able to install glass panels at a rate of one floor per week."[41] By November 17, the tower's steel had reached 48 stories.[42]

The Port Authority announced on December 16, 2010 that 1 WTC had reached the 52nd floor, and had risen to over 600feet, marking the halfway point for the construction of the building's steel frame.[43] [44]

2011

By February 2011, the tower had reached 56 floors, 667feet above grade, while the glass panels reached the 27th floor.[45] On May 12, 2011, plans led to install prismatic glass on the building's base were cancelled due to technical problems.[46]

By June 15, 2011, One World Trade Center had reached the 70th floor, the glass facade installation had reached the 45th floor, and concrete flooring had been installed up to the 63rd.[47] On August 1, 2011, concrete workers and carpenters at the tower walked off the job one month after their labor contract had expired. The workers returned to work on August 3.[48] [49]

2012

Construction slowed from January to February 2012 due to an unseasonably warm winter which caused high winds and icing conditions to form on top of the structure making it hazardous for the construction workers. Further delays were caused by financial problems with a steel supplier which slowed delivery of steel beams to One World Trade Center. It took over two months to complete the 92nd floor.[50] With the weather improving in March and financial issues being resolved, the construction progressed above the 92nd floor. 1 WTC later surpassed the Bank of America Tower as the 3rd tallest in the city.[51] In May 2012, it was announced that the 408-foot spire originally planned to adorn the top of One World Trade will have its radome stripped, revealing the mast of the same height. This announcement was withdrawn in September 2013. On November 12, 2013, One World Trade Center was given the official height by the CTBUH as the Tallest Building in the Northeastern United States. (surpassing the Willis Tower amongst much debate), eleventh tallest in the world, and was given the title of the World's Tallest Spire. (Burj Khalifa, the tallest building in the world, has a shorter spire, despite starting at a higher altitude.)[52] [53] [54]

On June 21, 2012, One World Trade Center Topped out at roof level, leaving the building to rank around 30th place among all other skyscrapers. Construction slowed again from late June till mid July due to high temperatures which caused the building to remain at roof level, leading to a delay in the installation of the antenna spire. With temperatures easing by July 16, construction crews began installing parapet steel at the top of 1 WTC. On July 18, the first node steel was installed.[55] [56] On July 31, 2012, all corner parapet columns, also called "node steel", were installed around the perimeter of the tower. A special beam, signed by the U.S. President Barack Obama, local officials and the construction workers, was raised on August 2, 2012. A ceremony was held for the occasion, but officials denied that it was considered a topping-out ceremony.[57] By August 10, 2012, concrete flooring had been completed to the 93rd story of the tower, One World Trade Center had risen to the 105th floor and glass installation was at the 82nd floor.[58] The building was structurally topped out on August 30, 2012 when the last of the spandrel beams were installed between the parapet columns.[59]

In late 2012, the workers were installing a temporary steel framework at the top of the tower to support the 408-foot (124 m) steel spire during assembly. The spire was fabricated as 16 separate sections at a factory near Montreal, Quebec, Canada and was transported by barge to New York City in mid-November. Just after Thanksgiving, crews began to transport the spire segments one by one to the WTC site. Upon reaching the WTC site, the spire sections were being assembled, piece by piece, at the top of 1 WTC.

On December 12, 2012, the first of nine pieces of the spire were lifted to the 104th floor. Another nine smaller pieces were trucked in from Montreal.[60]

2013–2015

On May 10, 2013, the last two sections of the building's spire were installed making it the tallest building in the Western Hemisphere, and the 3rd tallest building in the world.[61]

The exterior elevator began removal in late January 2014 and concluded in early June 2014. Base cladding began in February 2013 and concluded in June 2014. Work began on the construction of the plaza surrounding the building in late 2013 and interior work was finished in November 2014.

The building opened in November 3, 2014, to 175 employees of publisher Condé Nast.[62]

On May 29, 2015, the One World Observatory, at the tower's top, opened to the public.[2] [63]

External links

40.7115°N -74.0133°W

Notes and References

  1. Web site: WTC builder on the project's status | The Real Deal | New York Real Estate News . The Real Deal . 2010-02-01 . 2011-11-17 . 2011-07-17 . https://web.archive.org/web/20110717023955/http://therealdeal.com/newyork/articles/wtc-builder-daniel-tishman-on-the-project-status . dead .
  2. Web site: One World Trade Center Observatory Opens to Public. usnews.com. U.S. News. 30 March 2017.
  3. News: New Dimensions in Design. Frangos. Alex. 2004-07-07. Wall Street Journal. 2018-03-23. en-US. 0099-9660.
  4. Governor Pataki, Governor McGreevey, Mayor Bloomberg Lay Cornerstone for Freedom Tower . July 4, 2004 . Office of the Governor of New York State . dead . https://web.archive.org/web/20061231232307/http://www.state.ny.us/governor/press/04/july4_04.htm . December 31, 2006 .
  5. News: Cornerstone of Freedom Tower removed. https://web.archive.org/web/20070108140050/http://www.cbsnews.com/stories/2006/06/25/ap/national/mainD8IF1PB80.shtml. January 8, 2007. June 25, 2006. CBS News.
  6. News: Messages of Love and Hope on a Freedom Tower Beam . December 18, 2006 . Chan, Sewell . The New York Times.
  7. News: First Freedom Tower Beam Rises At Ground Zero . https://web.archive.org/web/20061220065543/http://wcbstv.com/topstories/local_story_353063928.html . December 20, 2006. WCBS-TVV . December 19, 2006.
  8. News: Freedom From Fear . The New York Times . February 16, 2007. Nordenson, Guy.
  9. News: Spitzer, in Reversal, Is Expected to Approve Freedom Tower, Officials Say . The New York Times . February 13, 2007 . Bagli, Charles V..
  10. Statement by Port Authority Regarding Preparation of Towers 3 and 4 Bathtub at WTC Site to Allow Silverstein Properties to Begin Construction in January . December 31, 2007 . Port Authority of New York & New Jersey . dead . https://web.archive.org/web/20090916071342/http://www.panynj.gov/AboutthePortAuthority/PressCenter/PressReleases/PressRelease/index.php?id=1019 . 2009-09-16 .
  11. News: Long Journey of Freedom Tower Steel . https://web.archive.org/web/20150924041419/http://www.highbeam.com/doc/1A1-D8UVGEL01.html . dead . September 24, 2015 . Associated Press . Westfeldt, Amy . February 22, 2008. 2015-08-06.
  12. News: Silverstein: WTC Still on Track for 2012 Finish . . Ritter, Ian . March 13, 2008 . 2011-08-28 . https://web.archive.org/web/20110927182312/http://www.globest.com/news/1113_1113/newyork/169019-1.html . 2011-09-27 . dead .
  13. Web site: Rising from the Pit. WTC.com. March 17, 2008.
  14. News: Tom . Topousis . 'FREEDOM' RATTLED. New York Post . April 1, 2008.
  15. News: David W. . Dunlap . Replicas of New Tower Endure Nature's Fury and a Test Blast . New York Times . April 9, 2008.
  16. News: Weak Concrete Foundation Removed From Freedom Tower . NY1 . April 16, 2008 . April 19, 2008 .
  17. News: David W. . Dunlap . Not Yet on the Skyline, but Above Street Level . New York Times . May 19, 2008.
  18. News: David W. . Dunlap . Chamfer, Anyone? Cutting Corners on a Large Scale . New York Times . June 19, 2008 . July 13, 2008.
  19. News: David W. . Dunlap . The Choreography (Quickly!) of Concrete. New York Times . July 3, 2008 . July 13, 2008.
  20. World Trade Center Site Update . Ward . Chris. 2008 . Port Authority of New York and New Jersey . 13. June 30, 2008 .
  21. News: Michael . Frazier . Construction progress slow at World Trade Center site . Newsday . Newsday Inc. . Melville, New York . August 17, 2008 . dead . https://web.archive.org/web/20080901154543/http://www.newsday.com/news/local/newyork/ny-nywtc0818%2C0%2C4404790.story . September 1, 2008 .
  22. Port Authority Board Takes Action on Several items . September 16, 2008 . Port Authority of New York & New Jersey . August 28, 2011 . November 20, 2018 . https://web.archive.org/web/20181120111928/http://www.panynj.gov/AboutthePortAuthority/PressCenter/PressReleases/PressRelease/index.php?id=1121 . dead .
  23. News: Port Authority Approves Freedom Tower Contracts . . Bob . Hennelly . September 16, 2008 . September 18, 2008.
  24. News: David W. . Dunlap. Unblinking Eyes, for $20 million, at Freedom Tower . New York Times . September 24, 2008 . September 24, 2008.
  25. News: David W. . Dunlap . Phantom Freedom Tower Visible to All. New York Times . October 20, 2008 . October 21, 2008.
  26. News: Image Gallery . . February 11, 2009 . February 21, 2009 . dead . https://web.archive.org/web/20090215053207/http://www.panynj.gov/wtcprogress/image_gallery.html . February 15, 2009 .
  27. Web site: Huge column is largest installed at WTC tower – Life. NBC News . August 12, 2009 . March 13, 2010.
  28. Web site: World Trade Center Quarterly Report 3rd Quarter 2009 – Panynj.gov . 2011-11-17 . 2011-09-29 . https://web.archive.org/web/20110929044910/http://www.panynj.gov/wtcprogress/pdf/3Q2009_Report.pdf . dead .
  29. http://www.lowermanhattan.info/construction/project_updates/freedom_tower_26204.aspx1 World Trade Center (Freedom Tower)
  30. http://www.silive.com/news/index.ssf/2010/02/1_world_trade_center_reaches_2.html 1 World Trade Center reaches 20th-floor level
  31. http://www.nj.com/opinion/times/oped/index.ssf?/base/news-1/1273124715235280.xml&coll=5 World Trade Center project has begun to take shape
  32. http://www.nj.com/news/index.ssf/2010/05/port_authority_installs_cocoon.html Port Authority installs cocoon safety system around World Trade Center steel structure
  33. http://cityroom.blogs.nytimes.com/2010/07/14/18th-century-ship-found-at-trade-center-site/ 18th-Century Ship Found at Trade Center Site
  34. http://www.foxnews.com/scitech/2010/07/14/ship-buried-th-century-unearthed-wtc-site/ Ship Buried in 18th Century Unearthed at WTC Site
  35. http://www.latimes.com/news/la-naw-wtc-ship-20100715,0,3344391.story Buried ship found at World Trade Center site
  36. Web site: Dunlap. David W.. 2011-08-05. The World Trade Center Ship, From Stern to Stem. 2020-09-22. City Room. en-US.
  37. Web site: 2011-08-31. Pictures: 18th-Century Ship Found Under 9/11 Site. https://web.archive.org/web/20200813033405/https://www.nationalgeographic.com/news/2011/8/11-world-trade-center-ship-ground-zero-new-york-nation-science/. dead. August 13, 2020. 2020-09-22. National Geographic News. en.
  38. Web site: Port Authority Board Approves Agreement that Will Fully Restore WTC Site . Wtc.com . 2011-09-19 . 2011-11-17 . dead . https://web.archive.org/web/20111001042340/http://www.wtc.com/news/port-authority-board-approves-agreement-that-will-fully-restore-wtc-site . 2011-10-01 .
  39. http://www.democratandchronicle.com/article/20101028/NEWS01/101028004 World Trade Center tower reaches 44 stories high and curtain wall installation this month
  40. http://www.dnainfo.com/20101008/downtown/one-world-trade-center-prepares-shine One World Trade Center Prepared to Shine
  41. Web site: World Trade Center Tower Begins to Show Its Shimmering Face || News || World Trade Center || . Wtc.com . 2011-09-19 . 2011-11-17.
  42. Web site: World Trade Center Tower Begins to Show Its Shimmering Face . The Tribeca Trib . 2011-11-17 . dead . https://web.archive.org/web/20110928044854/http://www.tribecatrib.com/news/2010/november/799_world-trade-center-tower-begins-to-show-its-shimmering-face.html . 2011-09-28 .
  43. https://www.wsj.com/articles/AP963a03879d90473a8e230286ac9086e3 "1 WTC, aka Freedom Tower, reaches halfway mark"
  44. http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=10694936 "Freedom Tower half complete"
  45. http://www.panynj.gov/wtcprogress/pdf/feb2011-WTC-Progress-Newsletter.pdf "Construction Progress Around the WTC Site"
  46. http://www.huffingtonpost.com/2011/05/12/world-trade-center-update_n_860992.html "Prismatic glass facade for WTC tower scrapped"
  47. http://www.panynj.gov/wtcprogress/progress.html World Trade Center Growing This Summer
  48. https://archive.today/20120909075219/http://www.ny1.com/content/top_stories/144352/concrete-workers-end-strike-at-wtc-site "Concrete Workers End Strike at WTC Site"
  49. Joseloff, Matt and Stephen Nessen."World Trade Center Workers Walk Off Job for Second Day". WNYC News Blog, New York Public Radio, August 2, 2011
  50. Web site: WTC money woes resurface. Theresa Agovino. 29 January 2012. Crain's New York Business.
  51. News: One World Trade. Bloomberg .
  52. Web site: One World Trade Center Named Tallest US Building. David B.. Caruso. November 12, 2013. Associated Press. ABC News. https://web.archive.org/web/20131115015107/https://abcnews.go.com/US/wireStory/committee-ny-tower-tallest-building-20859063. November 15, 2013.
  53. News: Tallest building ruling: Willis Tower loses to One World Trade Center . Chicago Tribune . November 12, 2013.
  54. News: 1 World Trade Center Is Ruled Tallest Building in the U.S . The New York Times . Patrick . McGeehan . Charles V. . Bagli . November 12, 2013.
  55. Web site: Flickr Photo of Parapet and Node Steel. 7 July 2012. flickr.com.
  56. Web site: NEW YORK | One World Trade Center | 1,787' Pinnacle / 1,373' Roof | 108 FLOORS – Page 1255 – SkyscraperPage Forum . Forum.skyscraperpage.com . 2013-01-24.
  57. Web site: Special beam set to be raised at One World Trade Center | 7online.com . Abclocal.go.com . 2012-08-02 . 2013-01-24 . https://web.archive.org/web/20121017022950/http://abclocal.go.com/wabc/story?section=news%2Flocal%2Fnew_york&id=8758931 . 2012-10-17 . live .
  58. Web site: Lower Manhattan : 1 World Trade Center . Lowermanhattan.info . 2013-01-24 . dead . https://web.archive.org/web/20111216172827/http://www.lowermanhattan.info/construction/project_updates/freedom_tower_26204.aspx . 2011-12-16 .
  59. News: Higgs . Larry . One World Trade Center steel skeleton completed . Asbury Park Press . August 30, 2012 . 2012-08-30 . 2013-01-01 . https://archive.today/20130101225738/http://www.app.com/article/20120830/NJNEWS/308300075/One-World-Trade-Center-steel-skeleton-completed?gcheck=1&nclick_check=1 . dead .
  60. Web site: Lower Manhattan : News | 1 WTC Spire on Its Way to the Top . Lowermanhattan.info . 2012-09-11 . 2013-01-24 . dead . https://web.archive.org/web/20120928040848/http://www.lowermanhattan.info/news/1_wtc_spire_preparations_50218.aspx . 2012-09-28 .
  61. News: Newman. Andy. Crowning 1 World Trade Center. The New York Times. May 2, 2013. 2013-05-02.
  62. News: Barron. James. 1 World Trade Center, a Pillar of Resilience, Is Open for Business. The New York Times. November 3, 2014.
  63. Web site: Observation deck at World Trade Center's Freedom Tower to open May 29 . NY Daily News . April 7, 2015 . April 8, 2015 . Corky Siemaszko.