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Total Building Collapse from a Single Column Failure

gerrycan said:
So the furthest to the West that the girder can be pushed by means of thermally expanding beams to the East of it is equal to or less than 5.5in.
NIST claim 6.25in.
Your only option now in defense of NISTs theory is to claim that the column itself moved. This cannot happen due to restraint and the girder expanding to the column face inside the side plates.
You, and NIST need a new theory, and a new analysis.
Click to expand...
Wrong.

People try to explain but, you don't listen.

Remember when you said, if you didn't understand something, you would admit it? You lied(or you really are a true believer).
 
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gerrycan said:
So the furthest to the West that the girder can be pushed by means of thermally expanding beams to the East of it is equal to or less than 5.5in.
NIST claim 6.25in.
Your only option now in defense of NISTs theory is to claim that the column itself moved. This cannot happen due to restraint and the girder expanding to the column face inside the side plates.
You, and NIST need a new theory, and a new analysis.
Click to expand...

Did it occur to you that it possibly could have also sagged under load due to it's strength being compromised from the fire?

Are you aware it didn't sit on it's seat square relative to the column? Do you know the girder's angle relative to the column? How close was the beam relative to the column at it's closet point? Please post mechanical drawing of this.
 
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It's curious how gerrycan refers to the building in the present tense. "Cannot fall" "Cannot happen" "Beams can expand" - uh, dude, the building fell down.
 
gerrycan said:
Let's first deal with the question that you cannot answer first. We can discuss what difference it makes after.
Surely this can't be too difficult for a fully qualified architect such as yourself.

Do you believe that any of the beams to the NE of column 79 can expand more than 5.5in. ?

It's a yes/no thing animal.
Very telling, as i said it would be
Click to expand...

Very telling that you cannot let go of the minutia..........

Once again it doesn't matter
Once you get over the "pristine building" troofer fail, you may get it, but I have my doubts. :rolleyes:
 
Animal said:
Very telling that you cannot let go of the minutia..........

Once again it doesn't matter
Once you get over the "pristine building" troofer fail, you may get it, but I have my doubts. :rolleyes:
Click to expand...
Makes you wonder if they think about why these seats are as long as they are.

One inch is enough, right? (not that it matters in this case).
 
NoahFence said:
Restraint?

Is this the restraint provided by siffeners and side plates made of the same steel that is equally suseptible to weakening by say, a massive fire raging for about 7 hours unchecked?

:crazy:
Click to expand...
I actually laughed out loud at this.
Look again.
What do you see restraining the girder from C76 - 79.
NB not the girder spanning 79 and 44.
 

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DGM said:
Makes you wonder if they think about why these seats are as long as they are.

One inch is enough, right? (not that it matters in this case).
Click to expand...

And they will never understand how this

"Temperature gradients through the depth of the steel beams and girders were affected by the presence of the floor slab. Temperatures were uniform (within 1C) across the bottom flange and web, but the top flange temperature was less by up to several hundred degrees, because the slab acted as a heat sink (see Figure 4-6 to Figure 4-8)" (pg 391 NIST NCSTAR 1-9)

"The beam elements could model a linear temperature gradient across the section, but a uniform temperature was determined to be a reasonable approximation for the temperature profile in the beam and girder sections." (pg 392 NIST NCSTAR 1-9)

crushes their whole "the stiffeners would prevent the collapse from happening" myth.:rolleyes:
 
Animal said:
And they will never understand how this

"Temperature gradients through the depth of the steel beams and girders were affected by the presence of the floor slab. Temperatures were uniform (within 1C) across the bottom flange and web, but the top flange temperature was less by up to several hundred degrees, because the slab acted as a heat sink (see Figure 4-6 to Figure 4-8)" (pg 391 NIST NCSTAR 1-9)

"The beam elements could model a linear temperature gradient across the section, but a uniform temperature was determined to be a reasonable approximation for the temperature profile in the beam and girder sections." (pg 392 NIST NCSTAR 1-9)

crushes their whole "the stiffeners would prevent the collapse from happening" myth.:rolleyes:
Click to expand...
To this general contractor, this means. All bets are off, these things are twisting around like pretzels.

I've actually seen this in some fire repair jobs I've done. ;)

ETA: It's also could to push that 5.5" figure way past what NIST claims.
 
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LudicFallacies said:
Did it occur to you that it possibly also sagged under load due to it's strength being compromised due to heat?

Are you also aware it didn't sit on it's seat square relative to the column? Do you know the angle? How close was the beam relative to the column at it's closet point? Please post mechanical structural drawing of this.
Click to expand...

FYI
 

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Animal said:
And they will never understand how this

"Temperature gradients through the depth of the steel beams and girders were affected by the presence of the floor slab. Temperatures were uniform (within 1C) across the bottom flange and web, but the top flange temperature was less by up to several hundred degrees, because the slab acted as a heat sink (see Figure 4-6 to Figure 4-8)" (pg 391 NIST NCSTAR 1-9)

"The beam elements could model a linear temperature gradient across the section, but a uniform temperature was determined to be a reasonable approximation for the temperature profile in the beam and girder sections." (pg 392 NIST NCSTAR 1-9)

crushes their whole "the stiffeners would prevent the collapse from happening" myth.:rolleyes:
Click to expand...
It does no such thing.
How did NIST model conductivity in the steel, and the slab?
 
DGM said:
ETA: It's also could to push that 5.5" figure way past what NIST claims.
Click to expand...
Please show how a 53ft beam expands more than 5.5in.
What temperature is required for it to do so?
Remember that the beam will sag above 600C and lose the ability to push.
 
gerrycan said:
Please show how a 53ft beam expands more than 5.5in.
What temperature is required for it to do so?
Remember that the beam will sag above 600C and lose the ability to push.
Click to expand...


dontsweat_zps941e5ce6.jpg
 
gerrycan said:
Please show how a 53ft beam expands more than 5.5in.
What temperature is required for it to do so?
Remember that the beam will sag above 600C and lose the ability to push.
Click to expand...

Thought experiment for you.

What happens if something does not allow the beam to sag? (yes, I'm being purposely vague).
 
DGM said:
Thought experiment for you.

What happens if something does not allow the beam to sag? (yes, I'm being purposely vague).
Click to expand...

The building implodes in a manner very similar to a controlled demolition?

By George, I think I've got it!

*whisper whisper*

...Oh. :boxedin:
 
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