The terrorist attacks of 2001 riveted our attention on supposed deficiencies in our structural designs,
regardless of the fact that those structures, and the structures surrounding them, actually performed
well given the extreme loads to which they were subjected. While these attacks served as a call to
action to reevaluate our designs for these severe loads, the fact is that practitioners in the fields of
blast loads prediction and dynamic inelastic structural response prediction have been moving
steadily forward on research, guideline development and design practices for extraordinary loads such as blast and impact for the past four decades. Granted, these loads and the requisite analysis and designs to resist these loads have not been “textbook” practices in the past. The complexity of the loads and response mechanisms of individual components and assemblages of components has required that the development of the design practice in this field has been one involving a mix of empirical, analytical and, recently, sophisticated numerical methods.

This “Facts for Steel Buildings: Blast and Progressive Collapse” document serves to provide the latest information and guidance available for commercial and industrial buildings subjected to these extraordinary loads and responses. It is not intended to supplant existing guidance for hardened military construction for warfighters. The document presents background and definitions for explosive loads and progressive collapse, general principles of blast loads and response prediction, recommendations for structures designed to resist blast and mitigate progressive collapse, recent guidelines and Federal and DoD requirements, some observations from historical events, and some information on ongoing research.

This document is intended to be a “primer” for engineers, architects, developers and owners. A
follow-on and companion “Design Guide for Blast and Progressive Collapse”, to be published by
AISC, will provide detailed analysis and design recommendations.