Jonathan Barnett - forensic engineer for WTC7 collapse

"We were surprised that the building [WTC7] collapsed, we being the team that investigated what occurred on that day. There was some damage to the Tower 7 caused by debris that hit it from Tower 1 but the damage was certainly not similar in scope or magnitude to that caused by the aircrafts hitting Towers 1 and 2. Normally when you have a structural failure you carefully go through the debris field looking at each item, photographing every beam as it collapsed and every column where it is on the ground and you pick them up very carefully and you look at each element. We were unable to do that in the case of Tower 7". [Jonathan Barnett, PhD. Fire Protection Engineer charged with investigation of WTC7-collapse debris-field.] Cited from video testimony seen here: Also note: [Dear Prof. Barnett, I came across the following comment made by you to James Glanz of the New York Times of November 29, 2001, regarding the collapse of WTC 7 on September 11, 2001: "A combination of an uncontrolled fire and the structural damage might have been able to bring the building down, some engineers said. But that would not explain steel members in the debris pile that appear to have been partly evaporated in extraordinarily high temperatures, Dr. Barnett said."] www.aldeilis.net =============================================== Dr. Jonathan R. Barnett is a Professor at Worcester Polytechnic Institute (WPI). He holds appointments in Fire Protection engineering and mechanical engineering and is ...

Post Tension Slab

Crane Collapse at "Screamer" ride (aftermath) - Scandia Fun Center Sacramento

SACRAMENTO (CBS13/AP) — Scandia Fun Center remains closed while safety officials investigate how a maintenance crane collapsed, injuring two workers. California Division of Occupational Safety and Health spokesman Dean Fryer said Wednesday the investigation will take about four months. The workers were performing regularly scheduled maintenance on the Scandia Screamer, a 165-foot-tall, windmill-like ride, when the crane and part of the ride toppled over Tuesday afternoon. Two park employees were left dangling by safety harnesses in the air. One suffered a badly broken arm and leg. The crane operator, who was not a park employee, had minor injuries. Wednesday morning, caution tape still surrounded the twisted pile of metal that once was the Screamer. Scandia Family Fun Center spokeswoman Elizabeth Cuevas says she does not know when the park will reopen. The accident damaged the park's miniature golf course and batting cage. ************ i swear i drove by 5 minutes before this thing went down and the next thing i know its on the news. I drove by on my way to the shop and stopped for a quick video while they tried to upright the crane....with 2 more larger cranes. I have personally witnessed 2 crane tips in my lifetime and its never pretty! Subscribe to my new "V2" channel......a little off topic area i can post whatever i want rather then just car audio and bass! Also, dont forget to check out my website! Join the forum today and be part of one of the BIGGEST car audio ...

Post Tension Slab

WTC7 Fire and Collapse FOX5

WTC7 Fire and Collapse FOX5 GAITHERSBURG, Md.—The fall of the 47-story World Trade Center building 7 (WTC 7) in New York City late in the afternoon of Sept. 11, 2001, was primarily due to fires, the Commerce Departments National Institute of Standards and Technology (NIST) announced today following an extensive, three-year scientific and technical building and fire safety investigation. This was the first known instance of fire causing the total collapse of a tall building, the agency stated as it released for public comment its WTC investigation report and 13 recommendations for improving building and fire safety.Our study found that the fires in WTC 7, which were uncontrolled but otherwise similar to fires experienced in other tall buildings, caused an extraordinary event, said NIST WTC Lead Investigator Shyam Sunder. Heating of floor beams and girders caused a critical support column to fail, initiating a fire-induced progressive collapse that brought the building down. Video and photographic evidence combined with detailed computer simulations show that neither explosives nor fuel oil fires played a role in the collapse of WTC 7, Sunder said. The NIST investigation team also determined that other elements of the buildings construction—namely trusses, girders and cantilever overhangs that were used to transfer loads from the building superstructure to the columns of the electric substation (over which WTC 7 was constructed) and foundation below—did not play a ...



http://www.youtube.com/watch?v=0Zrm9PAdqxA&hl=en

Civil Engineering Overview