Essay about Collapse of the world trade centre

Submitted By Patrick -Lamb
Words: 1367
Pages: 6
Open Document
On the 11th of September 2001, the WTC collapsed after a 747 aircraft collided with each of the towers. The towers were created to withstand the impact of a commercial plane due to the 1945 impact of a B-25 bomber into the 79th floor of the Empire state building. The WTC was clearly created to withstand the impact of a plane not much smaller than the 767, yet, even though the plane was larger, its impact should not have caused such a critical failure that resulted in a total collapse. The Failure of the WTCs critical building components, was due to the initial ignition of the aircrafts leftover fuel creating an explosion which stripped the protective insulation from the critical supports, meaning that they were open to the flames and were weakened by the heat, which, along with the impact and added weight of the plane caused a total collapse.

The collapse of the south tower and the North tower are both because of the same reason; The heating of the key internal supports, Though we will focus on the south tower, as it collapsed first, and received more serious damage from the impact of the plane. The Boeing 767-200ER, united airlines flight 175 weighed 125.9 metric tonnes when it collided with the southern side of the WTC2. It was travelling at 870km/h it had a force of 110 000 kN The weight of the plane consisted of 98656kg of the airplane, cargo, passengers and other miscellaneous items, and 30000kg of jet fuel. The plane hit the southern side of the WTC2 at an angle of 6° vertically, 15° laterally, with a roll angle of 38° clockwise.

These factors all increased the damage to the WTC2 through a number of ways, Firstly, that the damage was spread over more of floors, meaning more chances to damage something critical, secondly, because of this the fuel and ensuing fires were spread over more floors, meaning the floors in the centre were surrounded by two or three floors of fire, both above and below it. And thirdly, as the plane entered diagonally across one corner of the tower, it acted much as a three legged table would, unbalancing one corner of the tower. Instead of the WTC1 where the plane collided at nearly 90° to the face of the building, in the centre, mainly damaging the internal supports on one side compared to the WTC2s damage to the internal supports on one corner.

As you can see, the planes collided on different sides of the separate towers; the WTC1 was hit on its northern side, while the WTC2 was hit on its southern side.

The Structure of the WTCs was common of the time they were built. They had a strong core surrounded by a latticework of steel supports supporting the outer wall. This latticework was aimed at stopping the collision of a plane, although a smaller one than the 767.

(generic design for each level of the WTC 1&2)
Concerning the actual steel involved in the construction, it would have been impossible to have exactly the same steel used for all supports. In fact, 2 0f the 24 samples of the perimeter columns had unsatisfactory yield strengths to NIST standards, as well as 2 of the 8 core column samples. There were several different types of steel involved in the collapse of the WTC but to summarise, we will focus on two types of steel used; the steel with a yield force of 4.1x108 N/m2 for the perimeter columns and 2.5x108 N/m2 for the core columns. Whenever steel is mentioned from now on, it will be pertaining to steel with yield strength of 4.1x108 N/m2 when pertaining to the perimeter columns and 2.5x108 N/m2 when pertaining to the core columns, that is, not concerning broad statements. The perimeter columns had a static stress of 4.2x108 N/m2 and a longitudinal strain of 0.0160m at room temperature. And the core columns had a static stress of 2.6x108 N/m2 and a longitudinal strain of 0.0336m at room temperature. Meaning that,
Perimeter Core

at room temperature.

At temperatures
Show More

Related Documents: Essay about Collapse of the world trade centre

Re Branding Manchester Essay example

Manchester Manchester was once the centre for British industry, specifically for the cotton trade, the introduction of the steam engine brought about a new establishment of factories around the centre of the city. This then brought about a mass production of cotton and by the 1830s cotton accounted for 50% of the city’s exports and 80% of the world production of cotton took place there. As there was a need for many workers and the factories had to be in the centre for means of transport, the workers…

Words 440 - Pages 2

9/11 Conspiracy Theory

billion dollars of damage. There are lots of conspiracy theories surrounding 9/11 but this essay will discuss the collapse of the Twin Towers and the Pentagon and the black boxes that were found in the World Trade Centre building. Conspiracy theorists believe that the Twin Towers were destroyed by controlled explosives as there were reports of explosions going off shortly before the collapse. However, there has been no evidence of explosives being found and going off despite hand searches, and there…

Words 809 - Pages 4

Essay On The Great Depression

people this period began before the market crash in prices and lasted until the Second World War (1939-1945). Even before the devastating stock market crash on Wall Street (the centre of stock market trading in New York, United States of America), unemployment in Australia was already at ten per cent. The Wall Street crash in October 1929 signalled the beginning of a severe depression for the whole industrialised world. After the crash unemployment in Australia more than doubled to twenty-one per cent…

Words 447 - Pages 2

Essay on Asian Currency

and overheating. Imports grew as a result of the increased disposable income and the growth in the economy put pressure on wages making local products more expensive and thus Thai exports less attractive. This resulted in an increasingly alarming trade gap with the deficit continuously widening. Throughout the 80’s and 90’s, from the boom to the bust, corruption was rife in Thailand and other Asian countries such Indonesia and Malaysia. The corruption in the region lead to much larger risks being…

Words 2356 - Pages 10

Background paper WTO

Strategies for sustainable trade Since the emergence of societies, trade has been essential in the development of a bigger civilisation and its progress along time. It has never been possible for any country to obtain all necessary resources by itself. In order for a country to be fully developed, trade will always be necessary. But trading methods are the real issue on an organised society. As these organised civilisations evolved into Nations and Nation States, trade became a more complex exchange…

Words 5035 - Pages 21

Essay about Globalization and Its Impact on International Finance

Preceded by first event called World War and followed by first really global war across Atlantic and Pacific. * The 19th century: globalization approaching its modern form. In this decade Industrialization allowed cheap production of household items using economies of scale, while…

Words 6133 - Pages 25

Mackinder or Mahan Essay

Who is more useful for understanding contemporary Geopolitics: Mackinder or Mahan? Use a major power to illustrate your points. In the current century that we live, the world is becoming a smaller place from the effects of technology and globalisation. In the 19th and 20th century, the theoretical works of Mahan and Mackinder were drivers of geopolitical thought. Both theorists’ have a similar framework where they studied political power, military strength and how they were affected by geographic…

Words 2125 - Pages 9

Quebec Separatism

will support, it was an important issue for Canada and relations with the United States of America between the years 1976 and 1980. This issue raised many fears in the United States because the threat of separation in Canada raised the threat of the collapse of unity in he United States. This essay will also support the idea that it was in fact the most important issue impacting the relationship between Canada and the United States in the years between 1976 and 1980. The threat of Quebecs separation…

Words 1765 - Pages 8

Free Trade Africa Essay

Money and Banking FREE TRADE IS IT PROFITABLE TO AFRICA? By Issam Lahjouji Free trade is a major challenge for all countries in the world. This concept is not entirely new because no country can be self-­‐sufficient, in isolation. Trade liberalization appears for various reasons, namely…

Words 3201 - Pages 13

Pest Analysis (Netherlands) Essay

deploying troops. The Dutch mission has already once been extended by two years (since 2006) and has cost 21 soldiers' lives. The Netherlands has become the first NATO member to announce its departure from the fight in Afghanistan, following the collapse of the center-right government over its involvement in the U.S.-led war against the Taliban. This case can set an example for other governments to reconsider their support for an unpopular war. Thus, situation with Afghanistan, economic future of…

Words 7217 - Pages 29