What NIST is Really About

[Architect]

This sounds like reverse-woo!

Is there a name for that?

And if anyone says "logic", you'd have to explain how all 47 core columns suddenly lost ALL support ability such that the top section began immediate free-fall decent.

Thanks

Immediate. That's what you really think? I see......it explains a lot.

I've explained this numerous times, ditto Newton's Bit and Ron. Yet none of the Truthers ever bother brushing up on their structures.

WTC was a composite structure comrising closely inter-related elements, each of which only worked as part of a clsoed system. The outer envelope carried wind loadings and approximately half the gravity load. The inner core carried the remaining gravity load and provided resistance against what is know as the overturning movement, i.e. horizontal loadings. At roof level the girder trusses redistributed the wind/overturning movements betwixt the two. Meanwhile the intermediate floors acted in tension to retain deformation of the outer envelop.

Now a composite system such as this will have a finite amount of redundancy, but it's not infinite. We can't keep removing components and expect the remainder to magically carry a vastly increased load - transmitted through different paths, at that - without reaching failure point.

This isn't like subsidence, where a wee crack opens in your gable and perhaps grows at a rate of 1mm a year until you get off your arse and call an engineer. These are elements with a massive imposed load from the upper storey failing. The loads redistribute very quickly. And when the elements they are redistributed to fail, a progressive collapse begins.

It's not immediate, it's just very, very quick.

The loads don't just hang around, you know!

 

[chillzero]

Stop trying to derail this into a discussion of the specifics of the WTC collapses. This thread is to discuss NIST and what it's aims were.

Replying to this modbox in thread will be off topic  Posted By: chillzero

 

[Apollo20]

NIST's collapse initiation time for WTC 1

Among the many series of video stills I have used to time the collapse of WTC 1 is the set found at:

http://wtc.1accesshost.com/blast.html

I have also taken one of einsteen's excellent WTC 1 "smearograms" that he posted over at PhysOrg and derived two plots, one for the roof line curve and one for the curve formed by the dark band near the top of the antenna.

(I did this by enlarging the smearogram on a xerox machine about 3 times and marking it up with grid lines.)

I have now also done a calibration to convert the smearogram data to time in seconds and drop in meters. The time calibration comes fron NIST's Figure 8-101 in NCSTAR 1-5A. (You can locate the particular video frame in the accesshost set that corresponds to NIST's Figure 8-101.) The drop calibration distance is pretty straightforward using the known vertical dimensions of the north tower.....

I get an excellent fit (R^2 = 0.9996 or better !!!) for each set of data from einsteen's plots to two simple parabolic equations:

drop (roof) = 2.6362 t^2 - 1.5223 t

drop (antenna) = 3.0305 t^2 - 0.8544 t

Now comes the good part!

By setting the drop equal to zero for each equation I get an effective collapse initiation time:

For the roof line: t (zero) = 0.5775 seconds

For the antenna: t (zero) = 0.2819 seconds

These are not strictly "absolute" times since we do not know the exact moment that the collapse started.

However, we see a DIFFERENT collapse initiation time for the roof line and the antenna, we shall call this difference Delta t.

Delta t = 0.5775 - 0.2819 = 0.2956 seconds

In other words:

THE ANTENNA STARTS TO DROP ~ 0.3 SECONDS BEFORE THE ROOF LINE!

This observation is also what the "experts" who wrote the article in Vol 72 of CIVIL ENGINEERING believed.

Unfortunately NIST, our standards bearer, thinks otherwise.

Also, the initial collapse acceleration derived from my equations above are ~ 6 m/s^2, which is well below g showing there was some resistance to the collapse.

Look's like NIST's 1.4 second estimate could be too low by about 1/2 second. Too bad NIST offer no insight into how it arrived at its collapse initiation time.

 

[Max Photon]

NIST is about standards, and fixity in standards

Ms. Zero, allow me...


What is NIST really about?

NIST is about standards. Without standards, a society is lost. Fixity in standards - that is, standards that don't change - is a central concept. (It's hard to build a factory with a variable meter.)

Although NIST is at first glance a science-oriented institution, it is a fact that NIST exists embedded in a political - a Machiavellian - world. Political science is always attempting to grab physical science and bend it to advantage.

Nowhere is this clearer than in the financial realm. There are principles of accounting and finance that have been around - in incredibly stable form - for eons. That's because these are principles founded on physical trade, and physical trade is bounded by - well - physics! Well now political science has distorted economic measurement science, the economic standard of value, and the economy itself so severely that the USDollar system - an artifact of this political distortion - is imploding.

It is important to understand that violating the principle of fixity, and changing a standard midstream, creates infinities of problems, and arbitrary winners and losers. In the financial realm, the essence of a synthetic currency system is that a "flexible" (read: shrinking) economic unit or standard allows politicians to create winners and losers at their whim - that is, to have the power to redistribute wealth arbitrarily. This way, they can pay off, or punish. That equals power, and political science is the science of power.

It is interesting to note that with respect to NIST and the NCSTAR Reports, any fiddling with scientific standards would - as always - create arbitrary winners and losers. For example, if the WTCs were CDs, then the perpetrators are winners, and those blamed are losers.


Max

 

[Pardalis]

It is interesting to note that with respect to NIST and the NCSTAR Reports, any fiddling with scientific standards would - as always - create arbitrary winners and losers. For example, if the WTCs were CDs, then the perpetrators are winners, and those blamed are losers.

And in the other case, if the towers weren't CDed?

See, I thought scientists needed to be objective and unbiased.

 

[Furcifer]

Among the many series of video stills I have used to time the collapse of WTC 1 is the set found at:

http://wtc.1accesshost.com/blast.html

I have also taken one of einsteen's excellent WTC 1 "smearograms" that he posted over at PhysOrg and derived two plots, one for the roof line curve and one for the curve formed by the dark band near the top of the antenna.

(I did this by enlarging the smearogram on a xerox machine about 3 times and marking it up with grid lines.)

I have now also done a calibration to convert the smearogram data to time in seconds and drop in meters. The time calibration comes fron NIST's Figure 8-101 in NCSTAR 1-5A. (You can locate the particular video frame in the accesshost set that corresponds to NIST's Figure 8-101.) The drop calibration distance is pretty straightforward using the known vertical dimensions of the north tower.....

I get an excellent fit (R^2 = 0.9996 or better !!!) for each set of data from einsteen's plots to two simple parabolic equations:

drop (roof) = 2.6362 t^2 - 1.5223 t

drop (antenna) = 3.0305 t^2 - 0.8544 t

Now comes the good part!

By setting the drop equal to zero for each equation I get an effective collapse initiation time:

For the roof line: t (zero) = 0.5775 seconds

For the antenna: t (zero) = 0.2819 seconds

These are not strictly "absolute" times since we do not know the exact moment that the collapse started.

However, we see a DIFFERENT collapse initiation time for the roof line and the antenna, we shall call this difference Delta t.

Delta t = 0.5775 - 0.2819 = 0.2956 seconds

In other words:

THE ANTENNA STARTS TO DROP ~ 0.3 SECONDS BEFORE THE ROOF LINE!

This observation is also what the "experts" who wrote the article in Vol 72 of CIVIL ENGINEERING believed.

Unfortunately NIST, our standards bearer, thinks otherwise.

Also, the initial collapse acceleration derived from my equations above are ~ 6 m/s^2, which is well below g showing there was some resistance to the collapse.

Look's like NIST's 1.4 second estimate could be too low by about 1/2 second. Too bad NIST offer no insight into how it arrived at its collapse initiation time.

The degree of error associated with this crude measuring system does not allow for time measurements in the order of 1/10000th of a second as you have done.

Isn't this bad science?

 

[OneRedEye]

Isn't this bad science?

The final result is expressed with a single significant digit.

 

[R.Mackey]

Haven't we been over this a million times?

Whether the antenna appears to move first or not depends on perspective. You can't consider any single video in isolation. As Dr. Greening has argued, sometimes vehemently, the upper blocks were rotating as collapse initiated.

Rotation trumps the idea of an unrestricted free-fall in the opening seconds. Furthermore, the edge furthest from the hinge could easily exceed 9.8 m/s², depending on its distance from the hinge point and the rotational speed.

It is rather amusing to see the conspiracy-minded folk's ears prick up, though, at the merest mention of "anomaly."

To comply with chillzero's reasonable instructions, NIST declares that the antenna did not fall first in NCSTAR1-6, page 151. There has been no credible challenge to this simple observation. I also add that, in my estimation, the antenna and thus the core could slightly lead the perimeter based on the failure mechanism, assuming the hat truss could not provide sufficient rigidity to maintain the upper block. I explain this on pages 101-102 of my whitepaper; this is speculative and beyond the scope of the NIST Report.