Gebäude 7 world trade center

Dr. Shyam Sunder, lead investigator, answers questions weist a news briefing on ehrenvoll 21, 2008, about"s three-year study des the collapse des World Trade zentral 7.

Du schaust: Gebäude 7 world trade center

The fall of the 47-story world Trade hauptquartier building 7 (WTC 7) bei New York stadt late an the afternoon von Sept. 11, 2001, was primarily due to fires, the national Institute des Standards and Technology ( announced on august 21 following bei extensive, three-year scientific und technical building and fire safety investigation. This was the zuerst known instance of fire causing die total collapse von a high building, ns agency proclaimed as that released zum public comment that is WTC ermittlung report and 13 recommendations for improving building und fire safety.

"Our study found that die fires bei WTC 7, which to be uncontrolled yet otherwise similar zu fires experienced an other tall buildings, caused an extraordinary event," said WTC lead Investigator Shyam Sunder. "Heating of floor beams und girders caused a crucial support column zu fail, initiating a fire-induced steady collapse that brought ns building down."

"Video und photographic evidence an unified with detailed computer simulations show that no explosives nor fuel oil fires play a role bei the collapse des WTC 7," Sunder said. The ermittlung team also determined that various other elements von the building"s construction—namely trusses, girders and cantilever overhangs the were supplied to auslieferung loads from the building superstructure to ns columns of the electrical substation (over which WTC 7 was constructed) und foundation below—did notfall play a far-reaching role an the collapse.

Mehr sehen: Corona Test Schule Bayern - Coronavirus: Bayerische Teststrategie



According to ns report, a vital factor top to die eventual collapse des WTC 7 was thermal expansion of long-span floor systems at temperatures "hundreds von degrees listed below those commonly considered in current practice zum fire resistance ratings." WTC 7 offered a structural system design in widespread use.

Citing its one neu recommendation (the various other 12 room reiterated from ns previously completed investigation of the World Trade center towers, WTC 1 and 2), ns investigation team said that "while die partial or gesamt collapse des a tall building due kommen sie fires zu sein a rarely event, we strongly urge building owners, operators und designers kommen sie evaluate buildings to ensure the adequate fire performance des the structural system. Von particular problem are die effects of thermal expansion in buildings v one or more von the adhering to features: long-span floor systems, connections notfall designed zum thermal effects, asymmetric floor framing and/or composite floor systems." Engineers, the mannschaft said, should be may be to entwurf cost-effective fixes kommen sie address any kind of areas von concern identified über such evaluations.

Mehr sehen: Mainhardt Graf Von Nayhauß, Medien: Kolumnist Gestorben welcomes comments on ns draft report and recommendations received über noon east Daylight Time ~ above Sept.15, 2008. Instructions zum submitting comments—as fine as links to die complete text von the draft WTC 7 investigation report, archived videos von the Aug. 21 drücken sie briefing and bei Aug. 26 technological briefing, a videobilien describing the WTC 7 investigation findings, und other materials—may be accessed hinweisen