U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Fahim H. Sadek (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 99

Temperature-Dependent Material Modeling for Structural Steels: Formulation and Application

April 15, 2016
Author(s)
Mina S. Seif, William E. Luecke, Lisa Y. Choe, Joseph A. Main, Joseph D. McColskey, Chao Zhang, Jonathan M. Weigand, John L. Gross, Fahim Sadek
This report presents the formulation and application of a newly developed temperature-dependent material model for structural steels. First it presents a model for computing the stress-strain behavior of structural steel for conditions appropriate to fire

International R&D Roadmap for Fire Resistance of Structures Summary of NIST/CIB Workshop

June 11, 2015
Author(s)
Jiann C. Yang, Matthew F. Bundy, John L. Gross, Anthony P. Hamins, Fahim Sadek, Anand Raghunathan
This report summarizes the results of the global meeting to develop the International R&D Roadmap for Fire Resistance of Structures (the Roadmap) held May 21–22, 2014, in Gaithersburg, Maryland. The workshop was sponsored by the National Institute of

Behavior of structural steel moment connections under fire loading

March 24, 2015
Author(s)
Mina S. Seif, Joseph Main, Fahim H. Sadek
Performance-based methodologies to evaluate the fire performance of structures are needed to move beyond the prescriptive procedures presently in use. Analytical methods are needed for simulating the performance of structural systems, including connections

Robustness Assessment of RC Frame Buildings under Column Loss Scenarios

April 3, 2014
Author(s)
Yihai Bao, Joseph A. Main, Hai S. Lew, Fahim Sadek
A computational assessment of the robustness of reinforced concrete (RC) building structures under column loss scenarios is presented. A reduced-order modeling approach is presented for three-dimensional RC framing systems, including the floor slab, and

Robustness of Precast Concrete Frames: Experimental and Computational Studies

April 3, 2014
Author(s)
Joseph A. Main, Yihai Bao, Hai S. Lew, Fahim Sadek
This paper describes both full-scale testing and detailed finite-element modeling of a precast concrete moment-frame assembly extracted from the perimeter moment frame of a 10-story prototype building. The assembly comprises two beam spans and three

A Simple Means for Reducing the Risk of Progressive Collapse

December 1, 2013
Author(s)
Yihai Bao, Hai S. Lew, Fahim H. Sadek, Joseph Main
A simple debonding technique is proposed to reduce or eliminate strain localization in reinforcing bars in the region of wide flexural cracks in RC beams, and as a result enhance the resistance of RC buildings to disproportionate collapse. In this study

Structural Design for Disaster Resilience

October 28, 2013
Author(s)
Fahim H. Sadek, Joseph Main, John L. Gross, Therese P. McAllister
This paper presents a brief overview of research at the National Institute of Standards and Technology (NIST) on disaster resilience of buildings, infrastructure, and communities, including component programs and projects. NIST's efforts aim at developing

Modeling and Analysis of Single-Plate Shear Connections Under Column Loss

May 8, 2013
Author(s)
Joseph A. Main, Fahim Sadek
This paper presents a computational assessment of the behavior of single-plate shear (“shear tab”) connections in gravity frames under column loss scenarios. Two-span beam assemblies are considered under pushdown loading of the unsupported center column

Robustness of Steel Gravity Frame Systems with Single-Plate Shear Connections

February 27, 2013
Author(s)
Joseph A. Main, Fahim Sadek
This report presents a computational assessment of the performance of steel gravity framing systems with single-plate shear (“shear tab”) connections and composite floor slabs under column loss scenarios. The computational assessment uses a reduced

Structural Response of World Trade Center Buildings 1, 2 and 7 to Impact and Fire Damage

October 18, 2012
Author(s)
Therese P. McAllister, John L. Gross, Fahim Sadek, Steven W. Kirkpatrick, Robert S. MacNeill, Mehdi S. Zarghamee, Omer O. Erbay, Andrew T. Sarawit
The National Institute of Standards and Technology (NIST) conducted an extensive investigation of the collapse of World Trade Center towers (WTC 1 and WTC 2) and the WTC 7 building. This paper describes the component, subsystem, and global analyses

Overview of the Structural Design of World Trade Center 1, 2, and 7

September 1, 2012
Author(s)
Therese P. McAllister, Fahim Sadek, John L. Gross, Jason D. Averill, Richard G. Gann
This paper summarizes the primary structural systems which comprised World Trade Center 1, World Trade Center 2, and World Trade Center 7. The buildings were destroyed in the terrorist attacks of September 11, 2001. This paper describes the four major

Structural Analysis of Impact Damage to World Trade Center Buildings 1, 2, and 7

August 12, 2012
Author(s)
Therese P. McAllister, Fahim Sadek, John L. Gross, Steven W. Kirkpatrick, Robert S. MacNeill, R. Bocchieri, Mehdi S. Zarghamee, Omer O. Erbay, Andrew T. Sarawit
The National Institute of Standards and Technology (NIST) conducted an extensive investigation of the collapse of World Trade Center towers (WTC 1 and WTC 2) and the WTC 7 building. This paper describes the reconstruction of impact damage to each of the

Performance of Steel Moment Connections under a Column Removal Scenario. I: Experiments

April 3, 2012
Author(s)
Hai S. Lew, Joseph A. Main, Stephen D. Robert, Fahim Sadek, Vincent Chiarito
This paper presents an experimental study of two full-scale steel beam-column assemblies, each comprising three columns and two beams, to (1) define their response characteristics under a column removal scenario, including the capacity of the beams and

Performance of Steel Moment Connections under a Column Removal Scenario. II: Analysis

April 3, 2012
Author(s)
Fahim H. Sadek, Joseph Main, Hai S. Lew, Sherif El-Tawil
This paper presents a computational investigation of the response of steel beam-column assemblies with moment connections under monotonic loading conditions simulating a column removal scenario. Two beam-column assemblies are analyzed, which incorporate (1

Letter to the Editor of the CTBUH Journal

December 1, 2011
Author(s)
Sivaraj Shyam-Sunder, Jason D. Averill, Fahim Sadek
NIST was invited to comment on the articles written for a special issue of the CTBUH Journal, marking the ten years passed since the 2001 9/11 attacks on the World Trade Center. This letter to the editor reacts to the role of the NIST WTC Investigation

Modeling of Bolted Connections for Collapse Analysis of Steel Structures

September 19, 2011
Author(s)
Joseph A. Main, Fahim Sadek
In structural collapse scenarios, beam to column connections can be subjected to large rotations as the structure deforms, in addition to large axial forces associated with the development of catenary action. The capability of the connections to sustain

Draft Report on the Collapse of the Dallas Cowboys Indoor Practice Facility, May 2, 2009 (NIST IR 7636) ***DRAFT for Public Comments (for final version, see NIST IR 7661)***

October 6, 2009
Author(s)
John L. Gross, Joseph Main, Long Phan, Fahim H. Sadek, Stephen A. Cauffman, David P. Jorgensen
This report summarizes the National Institute of Standards and Technology (NIST) study of the collapse of the Dallas Cowboys indoor practice facility that occurred on the afternoon of May 2, 2009, during a severe thunderstorm. The indoor practice facility