metamars
24th March 2007 - 01:58 AM
Another Structural Engineer takes CD SeriouslyI tried to contact both Professors MacQueen and Professor Korol (with whom MacQueen is going to have a
discussion tonight) this morning, asking them to discuss the Calladine and English paper (more on that below). I was under the mistaken notion that Korol doubted the CD hypothesis.
I was quite mistaken in this, as MacQueen's email to me points out:
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"I'll forward this paper to Bob, but I doubt if he'll have time to look into
it before tonight's discussion. I should point out that Bob and I won't be
debating. We agree. I think the only difference is that Bob suspects it's an
inside job while I'm quite sure of it.
The event will be aimed mainly at people new to the subject, and for that
reason will contain a quite long film that explores the peculiar collapse of
the towers, but if you're able to come and add some more advanced knowledge,
so much the better!
Graeme"
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As for why I wanted them to discuss the Calladine and English paper, here is my initial email to Professor MacQueen:
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Dear Professor MacQueen,
Howdy. I sent the following email to the civil engineering department at McMaster University, in the hopes that they can get it to Professor Korol in time. I know that this is short notice, but if you could get a structural engineer or physicist to help you digest it's contents, I'd be thrilled to have it seriously commented upon by a structural engineer.
Basically, the Calladine and English paper seems to contradict the Bazant Zhou paper, which was used by NIST to "justify" not investigating the collapse, proper. I believe the key difference is due to treating the force applied on the topmost storey in a quasi-static fashion, while in actuality (as Gordon Ross has pointed out), energy is rapidly being carried away from the impact region.
Also, if you have Professor Korol's email address, would you be kind enough to forward a copy of this email, in case the engineering department does not do so? Thanks in advance.
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The NIST studies of the WTC collapse referenced the Bazant Zhou paper, which supported NIST's notion of an "inevitable global collapse". However, the Bazant Zhou paper has absolutely no evidence supporting it, and similar investigations (but more sophisticated) were carried out by Calladine and English (and probably others, I believe the Calladine and English paper referenced below was a seminal paper). The Calladine and English paper most certainly DID have experimental evidence.
Would you be knd enough to study the CE paper and remark on it's implications in your debate with MacQueen? Also, I have been urging other members of Scholars for 9/11 Truth and Justice to study the paper, and either submit a Letter or a Journal article. I suggested that they investigate the differences between it and both the Bazant Zhou paper and the Gordon Ross paper.
It would be much appreciated if you would oblige me, also.
Calladine, C. R. and English, R. W., "Strain-rate and Inertia Effects in the Collapse of Two Types of Energy-Absorbing Structure", Int. J. Mech. Sci., Vol. 26, No. 11/12, pp. 689-701, 1984.
Here is the summary from the paper:
Quote:
The dynamic collapse of energy-absorbing structures is more difficult to understand than the corresponding quasi-static collapse, on account of two effects which may be described as the "strain-rate factor" and the "inertia factor" respectively. The first of these is a material property whereby the yield stress is raised, while the second can affect the collapse mode, etc. It has recently been discovered that structures whose load-deflection curve falls sharply after an initial "peak" are much more "velocity sensitive" than structures whose load-deflection curve is "flat-topped"; that is, when a given amount of energy is delivered by a moving mass, the final deflection depends more strongly on the impact velocity. In this paper we investigate strain-rate and inertia effects in these two types of structure by means of some simple experiments performed in a "drop hammer" testing machine, together with some simple analysis which enables us to give a satisfactory account of the experimental observations. The work is motivated partly by difficulties which occur in small-scale model testing of energy-absorbing structures, on account of the fact that the "strain-rate" and "inertia" factors not only scale differently in general, but also affect the two destinct types of structure differently.
I will be sending a similar email to MacQueen, in the hopes that he can tap the expertise of structural engineers so that he can intelligently discuss the implications of the Calladine and English paper in your debate.
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