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The collapse of the World Trade Center towers on September 11, 2001, resulting from a combination of aircraft impact damage and subsequent fires, was studied as part of the Federal Building and Fire Safety Investigation of the WTC Disaster. This report
The National Institute of Standards and Technology (NIST) conducted a building and fire safety investigation of the World Trade Center (WTC) disasters. The work documented in this report was performed in support of the investigation of active fire
Thomas J. Ohlemiller, George W. Mulholland, Skandakumar H. Abeyesekere, James J. Filliben, Richard G. Gann
Reconstruction of the fires that occurred in the World Trade Center (WTC) 1, 2, and 7 on September 11. 2001, relied heavily on computer simulations because examination of the post-fire premises was not possible and the information from eyewitness accounts
Mehdi S. Zarghamee, Yasuo Kitane, Omer O. Erbay, Therese P. McAllister, John L. Gross
Simpson Gumpertz & Heger Inc. (SGH) developed global models of the World Trade Center (WTC) towers using finite elements to gain an understanding of the roles of the aircraft impact damage and the subsequent fires in the WTC towers with respect to
This report documents maintenance and modifications that were made to the structural systems of World Trade Center (WTC) 1,2, and 7. Included are the Port Authority of New York and New Jersey (PANYNJ or Port Authority) guidelines for inspection, repair
This report documents maintenance and modifications that were made to the structural systems of World Trade Center (WTC) 1,2, and 7. Included are the Port Authority of New York and New Jersey (PANYNJ or Port Authority) guidelines for inspection, repair
Frank W. Gayle, Richard J. Fields, William E. Luecke, Stephen W. Banovic, Timothy J. Foecke, Christopher N. McCowan, Joseph D. McColskey, Thomas A. Siewert
This report is an overview of the results of the mechanical and metallurgical analysis of structural steel from the World Trade Center (WTC), part of the National institute of Standards and Technology Investigation of the WTC disaster of September 11, 2001
William E. Luecke, Joseph D. McColskey, Christopher N. McCowan, Stephen W. Banovic, Richard J. Fields, Timothy J. Foecke, Thomas A. Siewert, Frank W. Gayle
This report provides five types of mechanical properties for steels from the World Trade Center (WTC): elastic, room-temperature tensile, room-temperature high strain rate, impact, and elevated-temperature tensile. Specimens of 29 different steels
Jason D. Averill, Dennis S. Mileti, Richard D. Peacock, Erica D. Kuligowski, N Groner, Guylene Proulx, Paul A. Reneke, Harold E. Nelson
Multiple sources of information were collected and analyzed: over 1,000 new interviews with survivors (including 803 telephone interviews, 225 face-to-face interviews, and 5 focus groups); over 700 published interviews; 9-1-1 emergency calls; transcripts
Nicholas J. Carino, M A. Starnes, John L. Gross, Jiann C. Yang, S R. Kukuck, Kuldeep R. Prasad, Richard W. Bukowski
This report deals with the passive fire protection used in the World Trade Center (WTC) towers. The main objective is to provide background information that can be used to assess the in-place conditions of the passive protection before and after aircraft
Stephen W. Banovic, Christopher N. McCowan, William E. Luecke
This report describes the physical properties of the structural steel recovered from the World Trade Center (WTC) towers. Analytical techniques were used to determine and evaluate the chemistry, microstructure, and thermal properties of the steels. While
Fires occurred in World Trade Center (WTC) I, 2, and 7 prior to September 11, 200 1. This report documents the facts of significant fires in the buildings after first occupancy as they relate to the performance of the automatic sprinkler, manual
This report was prepared to support the analysis of building and fire codes and standards of the National Institute of Standards and Technology World Trade Center (WTC) Investigation. The purpose of this report is to document the Port Authority of New York
This report was prepared to support the analysis of building and fire codes and standards of the National Institute of Standards and Technology World Trade Center (WTC) Investigation. This report was prepared to support the overall objective of determining
Richard G. Gann, Michael A. Riley, J M. Repp, A S. Whittaker, Andrei Reinhorn, P A. Hough
The degree of damage to the ceiling tile systems of the World Trade Center towers following the aircraft impacts on September 11, 2001, could have affected the rate at which the ensuing fires heated the steel- trussed concrete slab floor systems above
Richard G. Gann, Anthony P. Hamins, Kevin B. McGrattan, George W. Mulholland, Harold E. Nelson, Thomas J. Ohlemiller, William M. Pitts, Kuldeep R. Prasad
The collapses of the World Trade Center towers on September 11, 2001, resulted from a combination of aircraft impact damage and the ensuing fires. This report documents: The information obtained on the factors that affected the nature, duration and
This report establishes the baseline performance of the North and South World Trade Center Towers (WTC 1 and WTC 2) under design gravity and wind loading conditions. Baseline performance results include basic information about the towers behavior under
This report documents the design and installation of the smoke management systems in World Trade Center (WTC) 1, 2, and 7 and compares the designs to the requirements contained in applicable codes and standards. The normal operation of the fully functional
As a result of the recovery efforts of the Structural Engineers Association of New York. Federal Emergency Management Agency/American Society of Civil Engineers, and the National Institute of Standards and Technology (NIST), NIST possesses 236 structural
One of the four main objectives of the National Institute of Standards and Technology (NIST) investigation of the collapse of the World Trade Center (WTC) towers was to determine why and how the two towers collapsed. Events that played a significant role
This report documents the methods and outcomes of the telephone survey, face-to-face interviews, and focus groups that were conducted in support of the federal building and fire safety investigation of the World Trade Center disaster. In total, 803
William M. Pitts, Kathryn M. Butler, Valentine Junker
This report summarizes the collection and analysis of visual material used for the National Institute of Standards and Technology (NIST) World Trade Center (WTC) Investigation. The task consisted of four major subtasks: 1) identification, collection, data
William M. Pitts, Kathryn M. Butler, Valentine Junker
This report summarizes the collection and analysis of visual material used for the National Institute of Standards and Technology (NIST) World Trade Center (WTC) Investigation. The task consisted of four major subtasks: 1) identification, collection, data
William L. Grosshandler, Nelson P. Bryner, Daniel M. Madrzykowski, K Kuntz
A fire occurred on the night of Feb. 20, 2003, in The Station nightclub at 211 Cowesett Avenue, West Warwick, Rhode Island. A band that was on the platform that night, during its performance, used pyrotechnics that ignited polyurethane foam insulation
Provides details of the technical progress made since the May 2003 progress report on the World Trade Center (WTC) Investigation. The report includes a comprehensive summary of interim findings and accomplishments for each of the independent investigation