Colin Bailey

The British publication New Civil Engineer reports that, despite calls from leading structural and fire engineers, WTC collapse investigators with the National Institute of Standards and Technology (NIST) are refusing to show computer visualizations of the Twin Towers’ collapses. Despite having shown detailed computer generated visualizations of the plane impacts and the development of fires in the WTC at a recent conference, it showed no visualizations of the actual collapse mechanisms of the towers. Colin Bailey, a professor of structural engineering at the University of Manchester, complains, “NIST should really show the visualisations; otherwise the opportunity to correlate them back to the video evidence and identify any errors in the modelling will be lost.” A leading US structural engineer says that NIST’s “global structural model” is less sophisticated than its plane impact and fire models: “The software used has been pushed to new limits, and there have been a lot of simplifications, extrapolations and judgement calls.” [New Civil Engineer, 10/6/2005]