'What about building 7'?

[1stClassAlan]

What "remodel" are you talking about? The transfer system was part of the original design (on top of the sub-station).

I am NOT talking of anything below floor five!

As I said - go check for yourself - Salmon Brothers suddenly realised they needed a new HQ and had left it too late to build from scratch so they looked for a building that could be converted to their needs - WTC 7 was chosen for a number of reasons - the most important one I think, was it had lain empty for two years or more. It became the biggest remodelling job ever attempted - $200 million as far as I remember and involved entirely removing floor six so that large stand-by generators could sit two storeys high on floor five.

There are quite a few videos on line of the work in progress. Edit: here's a link to a good article. http://www.nytimes.com/1989/02/19/r...uilding-within-building-cost-200-million.html

 

[DGM]

I am NOT talking of anything below floor five!

As I said - go check for yourself - Salmon Brothers suddenly realised they needed a new HQ and had left it too late to build from scratch so they looked for a building that could be converted to their needs - WTC 7 was chosen for a number of reasons - the most important one I think, was it had lain empty for two years or more. It became the biggest remodelling job ever attempted - $200 million as far as I remember and involved entirely removing floor six so that large stand-by generators could sit two storeys high on floor five.

There are quite a few videos on line of the work in progress.

What does any of this have to do with the structure. They didn't change any structural framing (like you implied).

FYI: I've done my homework, how about you?

 

[1stClassAlan]

What does any of this have to do with the structure. They didn't change any structural framing (like you implied).

FYI: I've done my homework, how about you?

Go check again! Just what do you think they did with 375 tons of new steel? You obviously have very little grasp of what a "REMODELLING" on this scale involves.

 

[DGM]

Go check again! Just what do you think they did with 375 tons of new steel? You obviously have very little grasp of what a "REMODELLING" on this scale involves.

What do you think it means? Show me the framing plan and how it changed.

BTW, the transfer trusses extended well past floor five. Do your homework.

 

[DGM]

Are you claiming this was done after original construction?

ETA: This is all between floors 5-7.

 

[DGM]

1stClassAlan: Still waiting for you to school me on "what I don't grasp".

 

[LSSBB]

[qimg]http://www.internationalskeptics.com/forums/imagehosting/thum_170745452c7f0aff5c.jpg[/qimg]

Are you claiming this was done after original construction?

ETA: This is all between floors 5-7.

Looks to me from that diagram that column 79 was apart from the transfer trusses and cantilevers at floors 5-7, and the collapse initiated in the area of 79 under the first penthose, so that would rule those items out for collapse initiation, unless I am (very possibly) mistaken.

 

[Oystein]

...It became the biggest remodelling job ever attempted - ... involved entirely removing floor six so that large stand-by generators could sit two storeys high on floor five.

There are quite a few videos on line of the work in progress. Edit: here's a link to a good article. http://www.nytimes.com/1989/02/19/r...uilding-within-building-cost-200-million.html

Alan and DGM,

I guess the question is whether and how the retrofit and the removal of floors affected the structural integrity opf the steel frame. Two quotes from that NYT article:

"To create the extra height, workers are removing most of three existing floors, using jackhammers to demolish concrete slabs and torches to remove steel decking and girders beneath the concrete."​

''We built in enough redundancy to allow entire portions of floors to be removed without affecting the building's structural integrity, on the assumption that someone might need double-height floors,'' said Larry Silverstein, president of the company. ''Sure enough, Salomon had that need."​

Does this mean they removed some of the redundancy?
I understand, perhaps mistakenly, that removing floors themselves - the concrete and the steel decking - does not significantly effect the structural integrity, but what about girders, were they part of the designed lateral bracing for columns? Or only incidentally so?

 

[Crazy Chainsaw]

Removing floors and concrete can produce
A larger area for explosive vapors to build up.
Does anyone know the brand and type of
Stand by generators used.

The main fuel lines would have been
Steel the injector return lines would have
Been rubber.

Fuel leaking on the engines along with fires
A few messed up turbo chargers giving off oil
Vapor.

Damaged exhausts causing carbon monoxide
Reduced oxygen from the smoke intruding
Into the air filters.

Damaged vibration mounting on.the engines,
I would say the chance of back draft events
And vibration with heating damaging welds
Would be very high in that structure.

I didn't even add the carbon dust in the smoke,
That area would be a death trap to fire fighters
No wonder they were pulled.

 

[carlitos]

I think that MM's strategy is to become the most boring CT in history, so that everyone gives up and he can declare victory. Seriously, this is just tedious meandering around nonsense. Quoting 6 or 7 prior posts, using blue text for no reason, delving into silly minutiae; it's like trolling on quaaludes.

 

[jaydeehess]

Alan and DGM,

I guess the question is whether and how the retrofit and the removal of floors affected the structural integrity opf the steel frame. Two quotes from that NYT article:

"To create the extra height, workers are removing most of three existing floors, using jackhammers to demolish concrete slabs and torches to remove steel decking and girders beneath the concrete."​

''We built in enough redundancy to allow entire portions of floors to be removed without affecting the building's structural integrity, on the assumption that someone might need double-height floors,'' said Larry Silverstein, president of the company. ''Sure enough, Salomon had that need."​

Does this mean they removed some of the redundancy?
I understand, perhaps mistakenly, that removing floors themselves - the concrete and the steel decking - does not significantly effect the structural integrity, but what about girders, were they part of the designed lateral bracing for columns? Or only incidentally so?

"Girders" and "portions of floors" being the operative parts of that.
Was there anything about removing portions of columns?

Yes, the structure was built to allow for engineered removal of parts of floors to give extra height for tenants. I thought that was well known.
However, the NIST scenario has five or more floors collapsing, not one floor being carefully removed in a ordered, engineered fashion.

 

[jaydeehess]

Removing floors and concrete can produce
A larger area for explosive vapors to build up.
Does anyone know the brand and type of
Stand by generators used.

The main fuel lines would have been
Steel the injector return lines would have
Been rubber.

Fuel leaking on the engines along with fires
A few messed up turbo chargers giving off oil
Vapor.

Damaged exhausts causing carbon monoxide
Reduced oxygen from the smoke intruding
Into the air filters.

Damaged vibration mounting on.the engines,
I would say the chance of back draft events
And vibration with heating damaging welds
Would be very high in that structure.

I didn't even add the carbon dust in the smoke,
That area would be a death trap to fire fighters
No wonder they were pulled.

That speculative scenario is unfortunately not backed up with any observation or evidence of it actually being a reality in WTC 7, CC.

Besides a conflagration of diesel fuel vapours is not powerful enough to take out columns.

 

[Animal]

Alan and DGM,

I guess the question is whether and how the retrofit and the removal of floors affected the structural integrity opf the steel frame. Two quotes from that NYT article:

"To create the extra height, workers are removing most of three existing floors, using jackhammers to demolish concrete slabs and torches to remove steel decking and girders beneath the concrete."​

''We built in enough redundancy to allow entire portions of floors to be removed without affecting the building's structural integrity, on the assumption that someone might need double-height floors,'' said Larry Silverstein, president of the company. ''Sure enough, Salomon had that need."​

Does this mean they removed some of the redundancy?
I understand, perhaps mistakenly, that removing floors themselves - the concrete and the steel decking - does not significantly effect the structural integrity, but what about girders, were they part of the designed lateral bracing for columns? Or only incidentally so?

Typically, all parts of the structure are used for whatever load carrying is needed (Which is good engineering) The girders, beams and floor plates all would have been considered with regard to lateral stability etc.

 

[Crazy Chainsaw]

That speculative scenario is unfortunately not backed up with any observation or evidence of it actually being a reality in WTC 7, CC.

Besides a conflagration of diesel fuel vapours is not powerful enough to take out columns.

No but it is powerful enough with heating
To.damage welds on columns.

 

[JSanderO]

That speculative scenario is unfortunately not backed up with any observation or evidence of it actually being a reality in WTC 7, CC.

Besides a conflagration of diesel fuel vapours is not powerful enough to take out columns.

There was no one or vids from this region all day. There were no windows into the mech floors. We don't know what was going on in there. We DO know that there was at least one explosion that Jennings and Hess reported... likely electrical gear... or similar. What it did aside from collapse the stair which was adjacent / between / near TT1 and TT2 we don't know. If you know of any damage assessment reports from inside the transfer area / mech floor... please do share.

We do know there were hundreds and hundreds of gallons of diesel there, flammable HVAC refrigerant perhaps... transformers which CAN explode and release hot damaging gases. We know there were pumps which could supply fuel without the main power on... and no reports that these pumps were shut down. Can you cite reports that the diesel lift pumps shut down?

If you have evidence that the transfer/mech region down there was room temperature etc... cite it. Until such time this is a suspect area for the initiation.

 

[DGM]

Removing floors and concrete can produce
A larger area for explosive vapors to build up.
Does anyone know the brand and type of
Stand by generators used.

If memory serves they were Cats.

The main fuel lines would have been
Steel the injector return lines would have
Been rubber.

Doubtful on an interior installation. The only bare rubber lines are for cooling (and even then only in short sections). Oil and fuel are steel braid covered and the engine would shut down due to overheat long before they were compromised. Outside of the day tanks there wasn't that much fuel in the area and pressure transfer from supply tanks is only available if the gen-set is running. There's little evidence the gen-sets were running after the collapse of the north tower (likely due to ingestion of dust).

 

[DGM]

flammable HVAC refrigerant perhaps...

You keep saying this. The "refrigerant" was water.

transformers which CAN explode and release hot damaging gases.

These were dry air cooled.

We know there were pumps which could supply fuel without the main power on... and no reports that these pumps were shut down. Can you cite reports that the diesel lift pumps shut down?

They would shut down a soon as the gen-sets did. The evidence that the gen-sets failed soon after the north tower collapse is from video that shows the intake louvers closed.

If you have evidence that the transfer/mech region down there was room temperature etc... cite it. Until such time this is a suspect area for the initiation.

The problem is the transfer trusses were not in the same area as the gen-sets or fuel. They were in a separate area containing the HVAC.

 

[GlennB]

We DO know that there was at least one explosion that Jennings and Hess reported... likely electrical gear... or similar.

If you're talking about the event on the 6th floor then it's close to a 100% probability this so-called 'explosion' was the effects of the WTC1 collapse.

 

[Crazy Chainsaw]

If memory serves they were Cats.



Doubtful on an interior installation. The only bare rubber lines are for cooling (and even then only in short sections). Oil and fuel are steel braid covered and the engine would shut down due to overheat long before they were compromised. Outside of the day tanks there wasn't that much fuel in the area and pressure transfer from supply tanks is only available if the gen-set is running. There's little evidence the gen-sets were running after the collapse of the north tower (likely due to ingestion of dust).

You do know that I am refering to the injector
Fuel return lines which sometimes even in interior
Gen sets are rubber 1/4th inch lines?

Overheating can cause injector return lines to leak.

 

[Crazy Chainsaw]

You keep saying this. The "refrigerant" was water.



These were dry air cooled.



They would shut down a soon as the gen-sets did. The evidence that the gen-sets failed soon after the north tower collapse is from video that shows the intake louvers closed.



The problem is the transfer trusses were not in the same area as the gen-sets or fuel. They were in a separate area containing the HVAC.

Was there a heat exchanger?

Water is not a refrigerant, it requires a heat
Exchanger from the compressor to cool it.