Post by feelfree222 on Mar 2, 2007 16:45:52 GMT -4
lenbrazil said:
feelfree222 said:
Yep!
But how these floors falling on top of each other managed to also pancaking the central core steel pillars?
link to image
911research.wtc7.net/wtc/evidence/photos/construction.html
You obviously haven`t read the NIST report, perhaps you should before trying to "debunk" it.
Oh ! i only wanted to reserve that pleasure for the end
The New Civil Engineer (NCE), an engineering trade journal based in the United Kingdom, published an article highlighting NIST's failure to publish visualizations of its alleged analysis of "collapse initiation." e x c e r p t
title: WTC Investigators Resist Call for Collapse Visualization
authors: Dave Parker
WTC Investigators Resist Call for Collapse Visualisation
WORLD TRADE Center disaster investigators are refusing to show computer visualisations of the collapse of the Twin Towers despite calls from leading structural and fire engineers, NCE has learned.
Visualisations of collapse mechanisms are routinely used to validate the type of finite element analysis model used by the investigators.
The collapse mechanism and the role played by the hat truss at the top of the tower has been the focus of debate since the US National Institute of Standards & Technology (NIST) published its findings (NCE 22 September 2005).
NIST showed detailed computer generated visualisations of both the plane impacts and the development of fires within WTC1 and WTC2 at a recent conference at its Gaithersburg HQ. But the actual collapse mechanisms of the towers were not shown as visualisations.
University of Manchester (UK) professor of structural engineering Colin Bailey said there was a lot to be gained from visualising the structural response. "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," he said.
University of Sheffield professor Roger Plank added that visualisations of the collapses of the towers "would be a very powerful tool to promote the design code changes recommended by NIST."
NIST told NCE this week that it did not believe there is much value in visualising quasi-static processes such as thermal response and load redistribution up to the point of global collapse initiation and has chosen not to develop such visualisations.
But it said it would 'consider' developing visualisations of its global structural collapse model, although its contract with the finite element analysis subcontractor was now terminated.
A leading US structural engineer said NIST had obviously devoted enormous resources to the development of the impact and fire models. "By comparison the global structural model is not as sophisticated," he said.
"The software used has been pushed to new limits, and there have been a lot of simplifications, extrapolations and judgement calls.
OK they point out than...
This doesn't mean NIST has got it wrong in principle,
but it does mean it would be hard to produce a definitive visualisation from the analysis so far."
edited to add italics and bold are mine