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Dr. Knowles points out the structural failures of the World Trade Center due to steel beams and poor fireproofing material. Dr. Knowles connects the burning of the Capitol Building in 1814, the 1850 Hague Street boiler explosion in NYC, and Chicago’s Iroquois Theater Fire of 1903 to convey the different aspects of a structural disaster. The Capital Building focused on the investigation, the importance of the sentimental value of the building, and rebuild it as well as the difficulties involved with doing so. The Hague Street Explosion investigation attempted to pinpoint the root cause of the disaster, but after thorough investigation there were many failures at many different levels which led to the ultimate failure. The Iroquois theater fire revealed issues with public policy, regulation compliance, and public perception in addition to its investigation.

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With over 80 citations, and a wide variety of sources (few of which are repeated), we know that this research article was infer that a good deal of time and care was spent on this article. There are lots of citations to steel investigation, structural and architectural references, government building standards, similar historical disasters, and news articles reporting on 9/11. Without even reading the article, one can suppose a good deal about the article and how it was produced.

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The purpose of the article is to underscore the difficulties and importance of post-disaster research investigation into why exactly the structural collapse of the towers happened. Dr. Knowles does this by looking into the cause, investigation, and aftermath of several historical building catastrophes in the US.   These cases have reveal how politics, public, and private entities contributed to the disasters and what tends to happen in the aftermath. In the case of the World Trade Center, Dr. Knowles identifies the main reasons for the structures failing and how other sky scrapers are susceptible to the same attack. 

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Scott Gabriel Knowles, PHD is a department head and associate professor at Drexel University in the department of history and the center for science, technology and society. Prof. Knowles specializes in the history of technology, disasters, and public policy.

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seanw146
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The Iroquois Theater Fire, the destruction of US Capitol Building, and the Hague Street boiler explosion are used as historical examples to support the arguments made in the article as well as the findings of a steel expert who investigated the collapse of the towers.

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1) “It has been six months, and nobody knows who is responsible for what. It is a disgrace.”

2) “Six months after the World Trade Center collapse, the greatest structural disaster in modern history, people were still seeking to answer the question: why exactly had the Towers collapsed?”

3) “With the exception of federal oversight, Iroquois set the tone for investigation of modern disaster from the Baltimore Conflagration (1904) to the World Trade Center collapse.”

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1) I followed up on the old safety features of the World Trade Center. Sprinklers were the only feature that stood out from a fire safety video by the New York and New Jersey Port Authority for the World Trade Center (made 1996). https://www.youtube.com/watch?v=aBM9-y8gfHo. However the fire was much too large for them to put out, and may have even made it worse because water, when in contact with molten aluminum explodes.

 

2) Next I looked into why and how the World Trade Center (WTC) collapse happened. The WTC did not have concrete core or outer. Most high-rise buildings have one or the other as concrete is not subject to fire. The WTC steel trusses and columns were fireproofed with spray foam which fell off the building on impact with the airplane. The crash through the building resulted in flammable debris getting pushed to the far walls and corners, the most vulnerable location, and fatally weakening the WTC’s steel core. NIST report never stated that the fire melted the steel beams, steel melts at 2750 degrees F, but looses half its strength at 1100 F. Parts of the WTC fires reached 1800 F on that day. With the weakening, the trusses began to sag, bowing inward causing all of the weight to rest on the perimeter columns which could not bear the load and eventually snapped. After the first floor fell, the “pan-caking” effect resulted in each floor collapsing the one beneath it.

 

3) Lastly I looked at the new disaster prevention features of One World Trade Center. The key features which the Twin Towers were lacking are: a concrete core with stairwells located in center, larger than required staircases, and a separate first responder stairwell. Many experts believe if the WTC had a concrete core, they would not have fallen.