The Indiana State Fair Collapse Incident: Anatomy of a Failure

On the evening of August 13, 2011 the Temporary Ground-Supported Structure Used to Cover the Stage Area and Support Equipment in the Production of Outdoor Entertainment Events located over the Grandstand Stage at the Indiana State Fair (the ISF Structure) collapsed while the audience was waiting for the headline act to begin. The incident resulted in the death of seven individuals and a multitude of serious injuries. At the request of the State of Indiana and the Indiana State Fair Commission, Thornton Tomasetti mobilized to perform a multi-faceted highly detailed cause and origin investigation of the failure. The resulting investigation included the documentation, measurement and cataloging of thousands of components from the aluminum truss roof system and related suspended entertainment technology equipment, detailed site measurements, laser scanning, wind tunnel analysis, materials testing and analysis.