The 9/11 Forum

Much the same creasing can be observed high up (and early) on a face of WTC 2. I suspect this is a failure mode of
http://en.wikipedia.org/wiki/Truss#Vierendeel_truss
for which there may well be some literature about.

David B. Benson wrote:Much the same creasing can be observed high up (and early) on a face of WTC 2. I suspect this is a failure mode of
http://en.wikipedia.org/wiki/Truss#Vierendeel_truss
for which there may well be some literature about.

Excuse me, but...

Yawn.

Please explain in detail how the observed ejecta was produced.

femr2 --- Fractured bolts being shot out from the spandrel connections?

David B. Benson wrote:femr2 --- Fractured bolts being shot out from the spandrel connections?

*Dustified* bolts ? If not, where cometh the dust ? (Remember scale. We are looking at 12-24ft dust ejecta for each *blip*)

We are also looking bottom-up.

I'm open to rational explanation, but bolts don't convince me I'm afraid, especially without extensive structural explanation.

femr2 wrote:

David B. Benson wrote:femr2 --- Fractured bolts being shot out from the spandrel connections?

*Dustified* bolts ? If not, where cometh the dust ? (Remember scale. We are looking at 12-24ft dust ejecta for each *blip*)

We are also looking bottom-up.

I'm open to rational explanation, but bolts don't convince me I'm afraid, especially without extensive structural explanation.

Here's a question for you - where is this face in relation to the face that NIST claim the collapse initiated on?

Trippy wrote:Here's a question for you - where is this face in relation to the face that NIST claim the collapse initiated on?

Cannot see the relevance of the question, at all. Please elaborate.

femr2 wrote:*Dustified* bolts ? If not, where cometh the dust ?

Each pixel represents about 0.25 m vertically.

(Remember scale. We are looking at 12-24ft dust ejecta for each *blip*)

Some sort of ejecta. Do these extend but 4--8 m from the wall? Are you stating the ejecta are 4--8 m in diameter? Once again, I'm lost.

We are also looking bottom-up.

Not a problem. The load becomes increasingly eccentric and so the point of failue moves also.

Might be a good idea to compare to the creasing, seen almost face on, high up and early on for WTC 2.

femr2 wrote:

Trippy wrote:Here's a question for you - where is this face in relation to the face that NIST claim the collapse initiated on?

Cannot see the relevance of the question, at all. Please elaborate.

Part of what I do

I was just thinking about over stressing/under stressing and the such. I thought it might be significant if it was on the same face the collapse initiated, or on the opposing face (maybe i'm wrong, and it makes no difference, so be it).

Don't ask me to justify the question with a possible causal mechanism, because I can't at this time.

Trippy --- The view of the pic in the first post on this thread seems to be of the east side. The collapse started on the south side.

David B. Benson wrote:Each pixel represents about 0.25 m vertically.

Sauret video? This is a different video.

OneWhiteEye wrote:This is a different video.

Right, I forgot.

Your estimate?

David B. Benson wrote:Your estimate?

There are two videos excerpted above. Roughly 0.6m/px for the NBC video, though it's hard to tell. The other one, maybe around 1.5m/px; even harder to tell. Just quick and dirty, though, very fast and loose 'measurements'.

OneWhiteEye --- Thanks. My point is that what is called "dust" may actually be fairly sizable objects.

Try around pages 348--349 here:
http://books.google.com/books?id=RCM7kI ... re&f=false
This isn't quite what I wnated, but the closest I could readily find.

This pdf isn't much better, due to the very different connections used:
http://www.ppgciv.ufscar.br/arquivos/Fi ... /alex3.pdf
but it does include test to fialure of the (more ordinary) trusses.