why did the 3rd W. Trade Center bldg. collapse? it wasn't hit by a plane

[mopaul]

does anyone even remember it? i do. several hours after the second tower collapsed, as if in a deliberate demolition like the first one, a THIRD world trade center fell, IN EXACTLY THE SAME WAY. why? it wasn't hit by an airliner, yet if fell, into it's own footprints, the exact same way. why did no other buildings in the immediate area fall? someone suggested the vibrations from the first two massive towers made it fall, but why didn't any other buildings, besided the THREE world trade center buildings fall? the third building was only a few stories tall, not like the huge twin towers. yet it fell just like the first two.

i remember a t.v. commentator remark with amazement when the third, shorter wwtc building imploded. wow, how'd that happen? must've been vibrations or something.

no one ever talks about the third world trade center building's collapse. i wonder why. i'm the kind of a paranoid guy, who occasionally wonders why.

[Beetwasher]

1. Severe Structural Damage

This has been discussed before...

Many feel it was demolished on purpose...

Personally, I think the debris blow-out from the two collapsing towers, plus the fire that was burning in the building was enough to make it collapse from severe structural damage...

[Renew Deal]

2. It was 7 world trade.

Everything from teh other 2 buildings fell on it. It was on fire for a while and eventually collapsed. No one talks about it because it was evacuated adn no one was killed.

[DuctapeFatwa]

3. The regime has decreed that the 9-11 events not be looked into too closely

Calling attention to sensitive information that could embarrass the US or its allies might undermine support of the "war on terror."

[DoYouEverWonder]

4. This subject is still a hot topic

in the 9-11 forum. Plaguepuppy and a few others have done a lot of research on WTC7.

Unless the building was brought down on purpose, I have not seen an rational explanation as to why it imploded the why that it did.

[Renew Deal]

6. It didn't implode.

It fell on itself. I think that all the stuff that fell on it tore it apart. Remember, debris came from the top and the sides.

[DoYouEverWonder]

10. Would you like to explain the difference?

Between implode and fall on itself?

[nostamj]

5. it collapsed because...

falling debris from the North Tower caused significant structural damage and ingited huge tanks of diesel fuel that has been stored there.

this was the location of the Mayor's Emergency Mgmt Ctr. and Guiliani was nearly trapped there when the first tower came down.

the fires burned for (I think) 7 hours before the building collapsed.

to suggest that it was a controlled demolition requires one of these two scenerios:

1. explosives were planted there PRIOR to the attacks on the Towers and these explosives were unaffected by the HOURS of intense fire and damaged caused by debris from the North Tower so they could ignite a CD 7 hours later

or

2. explosives were placed in the burning building and detonated later.

neither holds water.

building damaged, building burns for 7 hours (with help from massive fuel storage tanks) and since the NYFD is a bit distracted by other events cannot effectively fight the fire, building finally collapses.

lots of BIG questions regarding 9/11, but this is not on my list of questions until someone comes up with a supportable theory for HOW the explosives were planted.

[Az]

7. Fire, shrapnel and a big crunch

Thats all you really need to bring down a building. The initial impact from the jets sent flame and shrapnel into the surrounding area. Tower 7 caught on fire. It burned. The towers came down. The impact was enough to set off seismic detectors. Local foundations were compromised and most buildings had to come down. Tower 7 just came down sooner.

Think like a conspirator. Your main objective is to not get caught. Your secondary objective is to carry out the plan. If the plan is to create a pearl harbor event you only need to strike the towers with planes. 2 planes in NY 2 in DC. Thats all you really need to get the job done. The buildings don't even need to come down.

The death toll from just the impact would be sufficient to get your event. The towers would have to come down one way or the other. No need for the total collapse. Impact is enough. The risk involved to guarantee the towers come down does not warrant the undertaking. Impact gets the job done. This is the criteria for a conspiracy.

The more people you involve the worse the risk. The more hard material left in place the worse the risk. To plant explosives would have required way too much control of the situation. Janitor, security, passerbyes, anyone witnessing the placing of the demolitions would have risked blowing the ceiling off the matter. Forget about finding the US personel willing to kill US citizens on a scale never before seen.

For a conspiracy to have any hope of succeeding it has to be kept relatively risk free, and small in numbers. In this case it is a simple matter of reducing observation on Ossama. Pushing a few buttons to get them riled up. And then waiting to see what happens. The goal is any sizable hit on America. OBL already has a history of going after big targets. Why risk yourself when you need only open the door and goad OBL into acting. Any action would suffice to provide PNACs Pearl Harbor.

[DulceDecorum]

8. Cement.

Look at the materials used in the construction of the entire WTC complex and then try to figure out if you can see any reason why they would collapse of themselves if not pulled within 30 years.

[OudeVanDagen]

18. cement .... what are you talking about?

Last month, DulceDecorum, on 1-26-04 you posted (#20) in the "NIST Testing" thread some blurbs and links about; high strength concrete, acid rains, high alumina concrete interacting with rusty steel beams and etc, etc. WHAT are you talking about?

[DulceDecorum]

28. What goes up

MUST come down.

Those buildings were doomed.
They were decaying from within.

That being so,
somebody somewhere decided arrange the timing of the oncoming
Spontaneous Massive Existence Failure (SMEF) of the WTC complex.

It was probably the only thing that could be done.

[Name removed]

31. Deleted message

Message removed by moderator. Click here to review the message board rules.

[DeadBroke]

19. I'm not getting it

Look at the materials used in the construction of the entire WTC complex and then try to figure out if you can see any reason why they would collapse of themselves if not pulled within 30 years.


I have been checking into the allegations that; substandard materials were used in the Trade Center, acid rain had some affect, and there were dangerous irreversible problems with dissimilar metals reacting. I can't find anything supporting those claims.

In the most general terms, buildings have three ages: 1) a chronological age - measured from the day construction ends, 2) a structural age - established by architectural design, construction technique, and material usage, and 3) an economic age - determined by the building's capacity to be profitable. The Trade Center was very young in each of these 3 categories.

The life span of any building depends on the materials it is constructed with, but the culture that built it and those who use it can prolong that life span. Unless there is neglect, abandonment or war that life span can be endless.

[Jose Diablo]

23. Would corrosion of the aluminum 'skin' affect the structural life? n/t

[LARED]

24. Unlikely

For starters aluminum is very resistant to atmospheric type corrosion. And I am pretty certain the aluminum on the WTC is just part of the facade, and adds little or no structural integrity.

[DeadBroke]

25. An answer

Even with all the talk and worries about acid rain, pollution and a dangerous warming of the earth; the aluminum column covers, aluminum window jambs, sills and heads, aluminum rain scuppers, and aluminum window washing tracks all were in good condition on 9/11; even much better condition than what was expected for 30+ year old structures.

The aluminum column covers and other outside trim items were regularly inspected. I looked into this by speaking with some of the inspection teams that were composite groups of ironworkers, glaziers, engineers, and PANYNJ facilities personnel. They were responsible for riding scaffolding and conducting inspections which took over 1 year to complete per tower.

The only problem related to me was that the window washer track would become impregnated with airborne farm grains that blew in from the west. There were no corrosion issues, thermal expansion and contraction rates were exactly as engineers had estimated during planning, and there was no creep in the expansion joints or at the points of fastening.

I have been able to see several recovered column covers. They still had the 1/4-20 fasteners and eel slips on them. Eel slips are 1/16" and larger thick neoprene sheets that fit wherever two different types of metals will come in contact with one another and isolate them - or keep them from touching.

As far as #7 goes, the granite and stainless steel curtain wall was also inspected. There was no bowing of granite panels, and the stainless also had normal thermal cycle expansion and contraction rates.

[DeadBroke]

44. A follow-up

I just spoke once again with an ironworker who at times would run the inspection scaffolding at the Trade Center. The information he gave me I hope will allow me to contact other members of the teams and inquire into their duties and the goals and findings of their studies.

In his words the Trade Center was a "kinda a test lab" where PANYNJ engineers and contractors conducted numerous daily studies. In his time there he saw how sections of the aluminum panels were covered with mylar sheeting, and then after several months, the mylar was removed. The once-covered section was then compared to the un-covered section and both were tested for damages from pollutants and examined for corrosion and etc. Small quarter sized motion detectors were sometimes attached and later removed. They measured contraction and expansion of the panels.

[DulceDecorum]

27. Go look up cement

and especially high strength cement.
Research the history of cement. Portland cement.
Cement is the main ingredient in the building material known as concrete.
http://www.cement.org/basics/concretebasics_faqs.asp
Try to discover WHY concrete had been rejected as a viable building material until about the early 20th Century.
Compare European cement/concrete standards to those of the US.
Try to identify the nature and agandae of those who write the US building codes and the relationship these committees, companies, and public relations companies, have with lobbyists and lawmakers.

DeadBroke,
you seem to think that concrete is a durable material,
and you are not alone in this erroneous belief.
Why do they have to re-inforce concrete in the first place?
What happens once the steel re-inforcement begins to rust from WITHIN the water-absorbing concrete?

Type the words CONCRETE DURABILITY into a search engine and see what comes up. Type in MUNDIC CONCRETE.
Type in HIGH ALUMINA CEMENT.
Chances are, you will discover that concrete structures, and most especially those in the (eastern) US, survive for an average of thirty odd years.

MAGNESIUM CEMENT DEVELOPED HAVING HARDNESS OF GRANITE
The expression “as hard as rock” will have to be changed to “as hard as cement” if the experiments of Dr. Howard S. Lukens of the University of Pennsylvania Chemistry Department work out as he has reason to think they will. For 6 years Dr. Lukens has been working with a combination of magnesium oxide and magnesium chloride, and he now has a cement that has the tensile strength of 2000 pounds per square inch. It is as hard as granite.
The catch is that the cement so far can be used successfully only for interiors, for water does something to it and it disintegrates. However, it is now possible to fabricate a stable magnesium cement product that does not absorb moisture from the air, and that is something ordinary Portland cement has never overcome.
http://www.sciencenews.org/articles/20011020/timeline.asp

From reading that short piece, you can, hopefully, begin to see some of the problems encountered by those who choose to construct concrete edifices. For example, if this particular cement was used in a modern building, and the sprinklers happened to be set off, the entire structure could very well collapse - NOT because of the fire - but because of the reaction between the magnesium and the water.

Everything made of cement is going to collapse.
The only question is "WHEN?"
http://bible.gospelcom.net/cgi-bin/bible?language=english&passage=Daniel+2%3A43&version=NKJV;NASB;DARBY;ESV;NIV;

So much for your concrete and steel.

[LARED]

30. Fascinating DD, really

But I do have a question for you. As interesting, (although completely irrelevant) this information is, how did you miss the fact that the WTC towers were steel buildings, not concrete?

[DeadBroke]

32. Not buying it

I have tried being polite and cooperative in the 9/11 treads, and have made every effort to avoid confrontation. I hope my response will be received accordingly.

I'm not buying it. A while back, after reading some replies that in general pointed at the concrete, I started digging. All I can find is that the Trade Center used the best possible concrete available in that era; made with the finest cement, sand, and aggregate. The inspection records show that PANYNJ, Tishman, and Berger inspectors visited the cement plants and concrete mixing plants at random times and that every load mixed and delivered passed the slump tests and that every sample drawn passed the 7-14-28 day tests with flying colors. Even the sand and crushed stone was monitored, for everything from water content to oil contamination.

Money was never an object with the PANYNJ and their specifications exceeded all standards; especially for curing the concrete, where hot/cold temperature cycles were monitored and every step followed from heating the areas with tarps and portable kerosene fueled heaters, to covering the concrete with visqueen and curing papers. The PANYNJ had lots of experience with concrete and also had consultants come in from Robert Moses' TriBoro. I'm not buying that the Trade Center only had 30 years of life, or that concrete was a culprit.

As for rebar, all I can say is that my back still aches from years of bending and tying. "Back in the day" we ironworkers would cut, bend and shape on site; not like today where everything is done off site, and usually overseas. I feel that you should look more closely at the rebar that was used at the Trade Center; the specs, the sizes, the low-boys and high chairs, layout and tie patterns, and even the specs for the mesh. You'll see that you're way off base.

[DulceDecorum]

34. Deadbroke,

I appreciate your opinions and the fact that you remain civil when expressing them.

Deadbroke says:
I'm not buying that the Trade Center only had 30 years of life, or that concrete was a culprit.

What I am saying about concrete is, in effect, dust to dust, ashes to ashes.
What I am saying is very controversial and there are many who do not support my iconoclastic views regarding cement and concrete.
But the trade mags appear to fully endorse my conclusions.

Sept. 12, 2001
"We know that concrete structures will eventually fail," said Krstulovic-Opara. "What we want to do is extend the length of time it takes for the structure to fail and control how it fails."
http://www.ncsu.edu/news/press_releases/01_09/247.htm
See what I mean?

So far I have NOT been PROVED wrong when I say that the CONCRETE is perishable.

February 1, 2004
There have been great advances in the understanding of concrete durability, especially in severe environments, yet durability still remains the foremost problem facing the industry today. We have only to look on our newly repaired bridges, parking structures, and buildings to see that we do not yet have adequate solutions; spalling, cracking, rust staining, and corrosion of reinforcing steel are visible problems. But behind these visible manifestations of concrete repair durability problems are more complex, invisible problems. This article will attempt to address some of these invisible problems in detail, namely the problems associated with applying experimental results to field conditions.
http://www.concreteinternational.com/pages/featured_article.asp?ID=12976

See what happens when Penta-concrete is exposed to DAILY temperature changes.

In the first 24 hours after the attack, structural engineers noticed the structure of Wedge One had shifted about 1/4 in. That measurement has since increased to about 1 in., officials say. But Lee Evey, program manager of the Pentagon Renovation Office, says the movement, along an expansion joint, could be an "old movement." Construction crews are noticing "micro fractures in the concrete," says Fontana.
Allyn Kilshimer, president of KCE Structural Engineers, Washington, D.C., says the cracks in the concrete and historic limestone facade are more the result from the drop in temperature in the evening and early morning hours, and that the amount of demolition work to be done has not changed. The temperature in Washington, D.C. had a 20-25°F change during the first few days in October. Kilshimer's firm was hired by Pentagon renovation officials to provide structural engineering oversite.
http://www.construction.com/NewsCenter/Headlines/ENR/20011009a.asp

And this next article will give you a clue as to the type of cement used in the Penta-concrete.

The corrosion and spalling on the Pentagon walls were caused by carbonation that occurs when carbon dioxide in the air penetrates into the concrete and reacts with hydroxides (such as calcium hydroxide) to form carbonates. While harmless to the concrete matrix, carbonation significantly lowers the alkalinity (pH) of the concrete. High alkalinity is needed to protect embedded steel from corrosion; consequently, corrosion will set in if carbonation of the concrete occurs.
http://concreteproducts.com/ar/concrete_equipment_products_21/

Now take a look at the manner in which the Penta-concrete was installed when the Wedge was rebuilt after September 11.
How long do you suppose that concrete is going to last?

Testing the concrete slabs every few days, crews found the compressive strength had reached between 75 and 85% by day 14, says Kilsheimer. Because the project is on such a compressed schedule, workers are removing the shoring from formwork supplied by PERI Formwork Systems Inc., Hanover, Md., ahead of the typical 28-day curing schedule. Still, says Colsten, "safety is paramount when considering how to get work done while the concrete structure is still a green structure."
Kilsheimer says that it is not unusual to reach "at least 75% of the compressive strength" on day 14. But it is unusual to strip the formwork at that time, he says. Crews first remove the shoring, followed by the formwork. They then install a limited number of vertical aluminum reshores at a much wider spacing—about 11 ft on center instead of 2 or 3 ft. That allows electrical equipment to be installed about one month ahead of schedule, says Kilsheimer. The sequence is "almost never done," even in an expedited situation, according to Kilsheimer. He says it will also be used to install mechanical systems.
The concrete standard for a facility like the Pentagon is 4,000 psi, but government officials note that the rebuilding effort has incorporated changes in reinforcing methods, resulting in a HIGHER STRENGTH CONCRETE. The U.S. Army Corps of Engineers suggested a series of methods to improve construction from a force protection and life safety perspective, but officials decline to discuss specifics.
http://enr.construction.com/projects/buildings/archives/020204.asp

It would apear that High Strength Concrete (HSC) was used in the the Phoenix Project. And what does NIST have to say about HSC?

December 1996.
A review is presented of experimental and analytical studies on the performance of concrete when exposed to short-term, rapid heating as in a fire. Emphasis is placed on concretes with high original compressive strengths, that is, high-strength concretes (HSC). The compiled test data revealed distinct difference in mechanical properties of HSC and normal strength concrete (NSC) in the range between room temperature and about 450 deg C. The differences decreased at temperature above 450 deg C. What is more important is that many test programs, but not all, reported that HSC experienced explosive spalling during the fire tests.
http://fire.nist.gov/bfrlpubs/build96/art075.html
http://fire.nist.gov/bfrlpubs/build00/art104.html
So it seems that an ordinary fire will cause severe and extensive damage to that newly-rebuilt Wedge. Incidentally, I cook tater-tots at 400 degrees and my oven can go up to 500 degrees. The tater-tots have NEVER exploded, unlike that concrete.

Let us return to the article which provided the original quote.

One of the problems with conventional concrete is that during extreme structural stress, such as is experienced during explosions or an earthquake, it breaks apart in large chunks and separates from the steel rebars. The result is that large slabs and chunks of concrete fall from the structure, hurting the inhabitants and crushing anything beneath them.
Krstulovic-Opara has been developing the HPFRC system using fibre mats injected with a special concrete slurry, a mixture of concrete, aggregate and liquids. The mats are made of recycled stainless steel fibres and come in large rolls that can be cut and shaped to fit the space or use desired. The fibre mats add tensile strength and ductility energy-absorbing properties to the concrete.
http://www.hindu.com/thehindu/2001/09/20/stories/08200001.htm

As you know by now, concrete is porous and is susceptible to water damage.
When the concrete absorbs water, the stainless steel fibers will be come coated with moisture which will cause the steel fibers to rust.
If high alumina cement was used, this could create problems.

The thermite reaction, discovered by Goldschmidt, is also a displacement reaction, but here aluminum reduces iron. The reaction is Fe2O3 + 2Al ? 2Fe + Al2O3, which liberates a good deal of heat. The liquid metal produced is at about 2300°C, which is very hot. Powdered aluminum and rust in the approximate ratio of 1:3 are packed in a refractory crucible with a magnesium ribbon, or a powder of magnesium and barium peroxide, to ignite it. Either the red or black iron oxide can be used, giving "red Thermit" or "black Thermit." A trade name for the powder is Thermit. The vigorous reaction makes liquid iron or steel, which flows out of a hole in the bottom of the crucible into the mold and can be used for welding. The stock to be welded is usually preheated with a gas flame playing through the mold. The metal produced is about half the weight of the original mixture. This reaction is also called aluminothermic, and can be used for reduction of other metals, such as nickel, manganese or chromium.
http://www.du.edu/~jcalvert/phys/alumin.htm

Aluminum powders can be used in wide ranges of application. Aluminium flakes for the production of aerated light weight concrete are getting more and more important all over the world. Through hydrogen development in the alkaline state a pore structure is created, which results in high insulation and absorption properties at low densities.
Research and development in connection with production know-how and competent advice ensure a leading position in the ALC industry as well as for manufacturers of light and insulating plasters.
Manufacturers of civil explosives and the pyrotechnical industry make use of the high oxygen affinity level of aluminum for, among others, the production of slurries (safety explosives), fireworks and sparklers. The reduction potential of aluminum is used for various chemical processes in the chemical industry.
Primary fields of application of aluminum flakes are:
Building materials - aerated light weight concrete, plasters (insulating, light and sanitation plasters)
Pyrotechnics - fireworks, sparklers
Explosives - watergels, slurry explosives
Chemistry - titanium oxide, Aluminium phosphite
http://www.schlenk.de/pigmente/eng/aluflakes.ihtml

And now let us look at insulation and fireproofing.
Shotcrete is pneumatically applied portland cement mortar made with an intimate mixture of Norlite and either portland cement or LUMNITE CEMENT. The material is shot into place by means of compressed air. For fireproofing structural steel members, proportions shall be in the 1:4 range for cement/aggregate.
http://www.norliteagg.com/maps/other.htm

While Portland cement is described throughout the world by the name Portland, HAC has a wide variety of names. In the UK it is known as High-Alumina Cement and Aluminous Cement. HAC also has a variety of trade names such as Ciment Fondu and Lightning Cement. Outside the UK it is known as Ciment Alumineux in France, LUMNITE in the USA and Tonerdezement or Tonerdeschmelzzement in Germany.
The HAC Problem
Within about 30 years serious faults had been found in a number of structures, and its use except by licence, was banned in France in 1943 and later in Germany. In 1973, the collapse of a precast, prestressed roof beams over a swimming pool in a London school led to its exclusion for structural purposes from British Standard codes of practice and deletion from the Building Research Establishment's recommendations for concrete to be placed in sulphate bearing soils and groundwaters.
http://www.eclipsescientific.co.uk/environmental/hac.html

There is much much more to learned about concrete
(concrete fracturing, concrete-eating bacteria, etc etc)
but I will not get into that right now.
Perhaps now you can see why we really ought to spend some time studying the cement and the concrete used in the manufacture of the entire WTC complex. Remember, some of the buildings there collapsed WITHOUT having been hit by anything.
Why did they do that?

Then, on Sept. 11, they were faced with something no one could imagine.
That morning, Merco/Obayashi had approximately 1,000 pounds of explosives loaded and scheduled to be shot in the afternoon.
Then the unthinkable happened in nearby Manhattan.
“We actually saw the planes hit the World Trade Center,” recalled Mike Mergentime, vice president, Merco Inc.
“Then we saw the towers collapse.” The impact of the tragedy was immediate.
“We already had security in place,” Mergentime said, “but, after the attack, we got armed U.S. marshals guarding the job site.” Authorities would not permit anyone to keep explosives on the site overnight, so the charges were exploded at 3:30 p.m. the afternoon of Sept. 11.
Understandably, nearby residents were shaken by the blasting, and the New Jersey State Police immediately were on the scene fearing it might be another terrorist attack.
http://www.concretepumpers.com/MagArticle.asp?ArticleID=237

[LARED]

37. Your slipping DD

What I am saying is very controversial and there are many who do not support my iconoclastic views regarding cement and concrete.
But the trade mags appear to fully endorse my conclusions.

You went ahead a stated you have a conclusion but did not share it with anyone. Can I point out a few things?

1. Other than a bunch of links about cement and concrete you have not actually stated a view other than you think because Tater Tots do not explode in the oven, if over-heated, concrete should act in a similar manner.

2. You have not made any connection to your cement and concrete views (whatever they are) and the WTC or any events of 9/11.

3. You have once again avoided actually stating any conclusions even though you think some trade magazines agree with you.

So please tell - how you believe concrete, cement, is related to the event of 9/11 and what conclusions you have drawn.

[OudeVanDagen]

33. centuries old

concrete ... CONCRETE Roman Dynasty aqueducts, temples and theaters still stand all over Europe, North Africa, and the Middle East ... and have withstood the same earthquakes that felled more modern structures.

Are you sure you want to state that concrete is a doomed building material? If your statement, quote:"The catch is that the cement so far can be used successfully only for interiors, for water does something to it and it disintegrates" is true, which it is NOT, then why is it holding up millions of miles of highway overpass?

Your credibility has eroded much faster than the cheapest redimix. What do any of your offerings have to do with WTC?

[DulceDecorum]

35. Reading comprehension

is very important.

From the October 17, 1931, issue
MAGNESIUM CEMENT DEVELOPED HAVING HARDNESS OF GRANITE
.....The catch is that the cement so far can be used successfully only for interiors, for water does something to it and it disintegrates. However, it is now possible to fabricate a stable magnesium cement product that does not absorb moisture from the air, and that is something ordinary Portland cement has never overcome.
http://www.sciencenews.org/articles/20011020/timeline.asp
OudeVanDagen,
were the Romans using this particular type of cement?

OudeVanDagen claims that concrete is "holding up millions of miles of highway overpass."
Take a look at just a few of these 8,830 sites that say different.
http://www.google.com/search?q=concrete+highway+crumbling&hl=en&lr=&ie=ISO-8859-1

Remind me, OudeVanDagen,
what was that you were saying about credibility?

[OudeVanDagen]

36. you

and the rest of the posse have NO credibility .... especially after reading that CIA crap you posted about the flight school visas .... the Roman era of construction is amazing ... even used sea shell aggregrates where there was no ocean .... I guess they had a form of CIA too.

[LARED]

38. Your comments about ancient civil works reminded me

of an article I read and thought you may find interesting

Pont du Gard, the aqueduct spanning the Gardon River north of Nimes, France, is one of the best surviving examples of Roman aqueduct construction. It transported water from a spring 20 km from the city center and only 14.6 meters above the point of delivery. In a straight line, this would have been a slope of a yard and a half per mile, but the route was far from straight. Because of the circuitous route, the channel's actual length was more than 50 km.

What an amazing feat.



It looks pretty good for beings 2000 years old and carrying water and being outdoors and all those elements that make cement and concrete evaporate, or something like that.

Link

http://asme.mondosearch.com/cgi-bin/MsmGo.exe?grab_id=15&EXTRA_ARG=IMAGE%2EX%3D14%00%26IMAGE%2EY%3D10&CFGNAME=MssFind%2Ecfg&host_id=42&page_id=13110272&query=aqueduct&hiword=aqueduct+AQUEDUCTS+

[DeadBroke]

40. water works

A few years ago the NYC Board Of Education had a program where retired tradesmen and professionals would give lecture tours. One of the best speakers, IMHO was a retired Sandhog named Sean O'Connell who worked his whole life in the water tunnels of NYC.

I loved listening to his lectures and Q and A sessions and really enjoyed his slide show that included great photos of the upstate dams, aqueducts and underground tunnels that supply NYC with all of it's water - entirely by gravity. O'Connell, in his lovable Irish accent would rattle off the names of engineers and governors responsible for the system and important dates relating to the water works.

He had 3 presentations; one for elementary schools, one for the regular high schools, and one for the industrial classes. Whenever he spoke to the classes with future tradesmen, architects and engineers he'd get into the use and durability of concrete, and explain how the NYC water system copies the type used by the old Roman Empire, right down to the grades or slope and sizes of the support arches.

O'Connell knew concrete well, especially about the curing process critical to NYC Water Tunnel #3 which has been under construction for over 50 years.

Another great speaker was an engineer who was employed by the Tri-Borough Bridge and Tunnel Authority and spent his lifetime in the departments that designed the Brooklyn Battery Tunnel and the Whitestone and Throgs Neck Bridges - structures that each needed millions of cubic yards of concrete.

All the highways and bridges near my NJ home were built by the WPA in the 1930s with reinforced concrete. Except for mountains of litter they look okay and pass annual DOT inspections. If concrete isn't any good, why is it in use nearly everywhere we go, everywhere we look; and why hasn't it been replaced with something better? I have read every link and honestly tried to be objective and understand the positions and theories offered, but I just don't see any problems with concrete - especially where WTC and 9/11 is concerned.

[DulceDecorum]

42. Roman concrete

was different from the stuff that we manufacture today.
The Romans used particular type of volcanic ash from Pozzuoli, Italy near Mt. Vesuvius. This ash is known as pozzolan or pozzolana. The Romans also used to mix blood into their cement, which something that we will never intentionally do.

The stuff that is in widespread use today is something called Portland cement which only dates back to 1824.
http://en.wikipedia.org/wiki/Portland_cement
http://www.cement.ca/cement.nsf/0/E5422FE72FC1740A852568C5004EDB33?OpenDocument
This Portland cement is the stuff that falls apart after twenty or thirty years. There are other new cements but they all have drawbacks and NONE of them is anywhere near as durable as the stuff that the Romans used.

Also, the Romans used to pound the cement once it was placed in layers on top of fist-sized rock aggregate. Tamped down concrete lasts longer.
http://nabataea.net/cement.html
Nowadays we pour the fluid mixture into a mold on-site and let it set by itself. Occasionally the mold may be vibrated to rid itself of air bubbles but this is not always the case. Furthermore, the cement mixture arrives by cement truck. Since cement will be quite stiff after half an hour, they stick in additives to keep it smooth and soft as the truck makes its way through traffic.

Here take a look at this table which gives a general overview of the history and development of cement and concrete.
http://matse1.mse.uiuc.edu/~tw/concrete/hist.html
Please also read this very brief and highly entertaining essay.
The life you save may be your own.
http://matse1.mse.uiuc.edu/~tw/concrete/hll.html
Now that you have read the essay, perhaps you will more fully appreciate the effect that aqueous pollutants have on the durability of concrete.

[DeadBroke]

43. Concrete public enemy #1 - Neglect

Thank you for the informative links. As a person who has earned a living in construction, I have developed a deep love for the histories of building products and construction methods, for the biographies of great engineers and builders, and for many of the building projects that we and newer generations give little thought to and take for granted; such as the great bridges, dams, highways and water works.

There have been some really good books written about NYC building projects; Brooklyn Bridge, Empire State Bldg, Tri-Borough Bridge, Verrazano Bridge, Holland Tunnel, LaGuardia and Trade Center for example. The biographies about the men who built some of them; The Roeblings, Robert Moses, Ole Singstad, David Steinman, and Othmar H. Ammann are great - especially the Robert Moses bio "The Power Broker" by Robert Caro, who may be better known for his books on President LBJ.

There are some similarities or common threads to be found in all these books. One similarity I found in all these books is the in depth study and research the author made into the building techniques and products used, that what made the project possible, (steel for bridge cables or for high rise columns for example), but each book author also talks about concrete.

Authors can not write about a building project or about the man who built it without telling the reader about concrete. The Verrazano Narrows Bridge which was built in the mid 60s, (this info is from my memory, so I'm sorry if I'm off) until 1981 had the world's longest span at 4,260 feet, has it's two towers set 180 feet deep - in concrete. Linking Brooklyn and Staten Island this structure dramatically changed New York - forever. It's worth repeating - the towers are set 180 feet deep in concrete. Every building project written about, or shown on the history/learning television shows deals with concrete in some manner. Concrete is what made many of them possible.

No doubt many of the roads, bridges, tunnels and infrastructures are in poor shape; but I believe that those conditions are caused by administration problems - budgets, spending and poor priority planning, which all create and result in neglect. I'll have to believe that neglect is the greater problem affecting the longevity of concrete than is the cement being used.

Thanks again for your links!

[DulceDecorum]

45. Re: neglect

The roads and aqueducts built by the Romans have NOT had half as much attention as have the roads, bridges and skyscrapers built in the US.

The fact of the matter is that Roman Concrete is a completely different material from modern concrete. And that is really all there is to it.

You will recall the concern that was universally expressed concerning the collapse of the skyscrapers. Numerous articles such as this appeared.
How safe are our skyscrapers?: The World Trade Center collapse
http://web.mit.edu/newsoffice/nr/2001/skyscrapers.html

The attacks of September 11 on the World Trade Center showed that New York's twin towers were well built. However, very tall buildings may have had their day
The destruction of New York's twin towers by terrorists has put the future of very tall buildings in doubt.
If they are not safe enough to ensure the survival of people within them, do they have a future?
The fate of skyscrapers is a subject of much discussion, not just in North America, where they grace some of the world's most thrilling urban skylines, but in London, Shanghai and the Arabian Gulf.
<snip>
Eerily, release of the report came shortly after a Piper light aircraft, flown by an experienced pilot described by his family as suicidal, hit the 30-storey landmark Pirelli Tower in central Milan.
Although far less destructive, the Milan crash suggests that structural engineers are entering a brave new world. Planners need to assume that their designs have to take into account anything that can be envisaged actually happening.
Reassuringly, people who should know best - insurers - insist that even now such events are likely to be very rare.
<snip>
And ironically, the FEMA review of the World Trade Center collapse comes years after engineers erected the last US super-tall building. The only part of the world still putting up skyscrapers, Ms Fenske says, is Asia.
http://www.sapoaonline.co.za/news/article.aspx?idArticle=522

Let me tell you here and now, those buildings are ALL doomed.
And the insurance companies know it.
But the authorities do not wish for y'all to realize or to be alarmed by this fact.
http://www.crsi.org/CRSI_Mission/crsi_mission.html
http://www.gop.gov/committeecentral/docs/bills/108/1/bill.asp?bill=hres394

7. Q. What is the effect of aging on concrete?
A. Aging, if one means merely the effect caused by the passage of time, has no effect on concrete. Of course concrete sets, hardens, gains strength, and exhibits reduced permeability with the passage of time, but it is not the passage of time alone that causes these things to happen. If the concrete is kept very cold, none of this will happen. If all moisture is removed, none of this will happen. Many or even most concretes are confronted with potential deteriorative service conditions. If the concrete has not been provided with immunity against these influences, it may well slowly deteriorate as time passes, but not simply because time passes. Concrete need not deteriorate.
http://www.aci-int.org/pubs/sp001.htm

So,
we should keep the concrete in a lab under strict temperature and moisture control?
Better we should find another building material.

Think about it.
This is the end of the Industrial Revolution.
Who is willingly going to go to work,
on a daily basis,
into a building that could collapse at any time?
There will be an exodus from the cities into the rural areas and an Industrial Counter-revolution once people wake up to the fact that modern concrete is perishing all around them.

In June of 1983, a 100-foot section of a Connecticut Turnpike bridge collapsed and fell into the Mianus River, killing three people and critically injuring three more. Hundreds of thousands of drivers had to find alternate routes for almost three months while repairs were made. The repairs alone cost the state of Connecticut over $23 million after insurance. Additional funds were disbursed to investigate why the collapse had occurred in the first place, since the 25-year-old bridge had passed inspection only nine months earlier.
As of November 1991, 35% of this country's 590,000 bridges were considered structurally deficient or functionally obsolete because of increased age and larger-than-expected service loads. Recent collapses or near-collapses have forced governments to develop extensive rehabilitation programs. Regulations require that bridges be inspected every two years, except old and high-risk bridges, which must be inspected more frequently. Current inspection techniques depend on human beings to recognize structural imperfections. A need to improve inspection techniques is evident.
http://www.dadisp.com/ab3.htm
http://www.ntsb.gov/publictn/1984/HAR8403.htm

Deadbroke, as you can see,
the Mianus River Bridge had PASSED INSPECTION ONLY NINE MONTHS EARLIER.
Yet it collapsed.
The World Trade Center was built to specs and was well-engineered.
Yet it too collapsed.
In both instances, the steel was blamed.
But the steel was only present to re-inforce the concrete.
The concrete itself is deficient.
Which is the reason why must be re-inforced in the first place.

Now, who writes the concrete specs and building codes?

Global reach of ACI — In 1904, when we were chartered as the “National Association of Cement Users, ” the focus was necessarily on the United States. Our interaction with Canada and then Mexico expanded this to North America. We now have 88 chapters, 55 of which are in the U.S.
http://www.concrete.org/about/ab_presmemo_coke03a.htm

All of this emphasizes the importance of the dissemination of knowledge about ACI’s new Building Code Requirements for Structural Concrete (318-99)
http://www.concrete.org/about/ab_presmemo_coke12.htm

What does the ACI have to say to the general public?

At an early convention of the American Concrete Institute (then known as the National Association of Concrete Users), a keynote speaker deplored existing conditions in the reinforced concrete industry, both design and construction aspects. At the 1912 convention in Kansas City, MO, John L. Harrington, described as a prominent consultant in that city, claimed that "cheap construction" had often resulted in "many failures and too much consequent damage to the industry." He called upon NACU members to "benefit the country at large by compelling a high standard of ability and integrity among cement users."
<snip>
All of us must do our part in what Gene Corley (a 318 instructor) so aptly described a few years ago as "protecting the public from fools and rascals." And he emphasized that there is no reason to believe that the next millennium will be free of fools and rascals—"consequently, we will continue to need .... (building) codes." Safety is a matter of grave concern to all of us, and the 318 Code is an important part of the Institute’s activities. We are justly proud of our part in protecting life and limb, and are anxious to continue these efforts abroad as well as at home.
http://www.concrete.org/about/ab_presmemo_coke12.htm

How durable are the structures that are built to these specs?

There is a national concern about premature deterioration of our infrastructure, including the concrete. Too many bridges, roads, highways, garages, and water treatment facilities require early repair and/or replacement. Repair and restoration is the fastest growing segment of the concrete industry. This not only drains municipal coffers, postponing new work, traffic delays irritate drivers like you and me.
For years, we have had the technology to produce durable, long-lasting concrete. In Ohio, there is a concrete city street over 100 years old and a 1940 bridge that has never required maintenance. Why are we not able to do such work today?
http://www.concrete.org/about/ab_presmemo_coke08.htm

[LARED]

46. All of this information about concrete is fascinating

What does any of it have to do with the collapse of the WTC towers?

[OudeVanDagen]

47. yes ... but ... no

The YES:

One (1) paragraph in link you offered states: "Q. Assuming that concrete is made from the correct ingredients and in the correct proportions, what other requirements must be met to ensure a durable structure, that is, a structure with long life? A. The important overall requirements are related to measuring, mixing, transporting, placing, curing, and inspection (ACI 304R):
(1) All materials should comply with specifications.
(2) The methods of storing, handling, and measuring all ingredients should be such that the selected mixture can be accurately obtained at all times (ACI 213, 221).
(3) The concrete should be adequately mixed, and it should be transported and placed by methods that will avoid segregation and loss of ingredients. The consolidated mass should be uniform without rock pockets or honeycombed areas (ACI 309).
(4) The arrangement of joints and methods for bonding successive lifts of concrete are important details that can vitally affect the performance of the structure even though the concrete itself is durable. Provisions should be made in the structural plans for drainage to avoid areas of constant saturation that would be more susceptible to damage by freezing than other portions of the structure (ACI 210.2R, 325.9R).
(5) Curing of the concrete should not be neglected. This includes protection against extremes of temperature as well as provision for ensuring availability of moisture during the critical early period. No detail of concrete construction offers such possibilities for increased strength and durability at so low a cost as is offered by the possibilities of better curing (ACI 308, 305, 306).
(6) Careful inspection should be enforced in all of the above operations (ACI Manual of Concrete Inspection, SP-2). After a dissertation on correct practices in the maintenance of the Roman aqueduct in AD 97, Julius Frontinius noted that “all these the workmen know but few observe.”

Yes, I'll buy all that. Those were the exact steps followed at WTC ... and every other building here in NYC, and elsewhere.

- - - - - - - -

The BUT:

From your narrative; quote: "So, we should keep the concrete in a lab under strict temperature and moisture control? Better we should find another building material." end quote suggests that WTC concrete floors had severe temperature swings and exposures to moisture and other destructive contaminants. Did it?

Was WTC concrete exposed to temperature swings, moisture and etc, ... or was the concrete used for WTC floors limited to the temp swings of the canned air systems low 70s temp heating in winter and mid 60s A/C in summer?

Your narrative sounds good, but does it really apply to WTC?

- - - - - - - -

The NO:

As you point out concrete itself does not offer exceptional strength. After ingredient selection, strength is achieved from reinforcement and shape. But concrete only offers strength in compression; it offers no tensile strength to structures when used for thin floors ... as was the scenario at WTC. WTC were two tubes ... a core and outer wall ... interconnected with floor trusses topped with a few inches of reinforced concrete. Is this thin layer of concrete with no tensile strength going to assist dampening the structure from motion ... the movement of the two tubes, especially after the main connection between the two tubes ... specifically the roof trusses have been removed from the equation? No.

Was age, deterioration, moisture or temperature changes and rusty reinforing steel factors in the collapse? No. Lack of tensile strength was.

- - - - - - -

I seriously enjoyed the links you offered and your narratives; I gotta tip my hat because if anything they all help explain; a) the conditions of the concrete in debris, b) venting, c) inability of the structures to dampen, d) drift, and e) the need to maintain programs to improve building products.

[DulceDecorum]

53. Re: thin layer of concrete

OudeVanDagen says:
Was age, deterioration, moisture or temperature changes and rusty reinforing steel factors in the collapse? No. Lack of tensile strength was.

How so?
And how did the WTC complex differ from all other buildings in New York which are constructed out of the same materials?

[OudeVanDagen]

54. very different indeed

The quote you offer was made by me in regards to the thin concrete floors poured atop the trusses that connected to the core columns on one end and to the outer walls on the other end. The concrete was an interior design element ... floors ... in a controlled environment of near constant heat and canned air; unexposed to moisture, weather elements, pollutants or wide temp swings. Inside the walls, under carpet, and over insulated ceilings; the concrete floors of WTC were protected against your worrisome destructive forces.

WTC radically departed from typical steel frame design. Unlike typical steel frame structures, WTC had trusses ... it had no intermediate columns and beams. Those who have been posting in these threads often point that radical difference out, and they also accurately describe WTC towers as a tube within a tube. The KEY connection element between those two tubes were the roof trusses ... which were necessary to dampen motion in this super tall AND superlight skyscraper.

Far too much focus in these treads has been put on the extreme event ... fires and fire temperatures. More scrutiny should be aimed at the connections ... something I've been preaching about. If someone is going discuss the tube design chosen, or state a theory about the strengths of the core and outer walls; well, the KEY connection element ... roof trusses ... MUST be included.

If WTC had been typically framed with intermediate columns and beams the unique roof truss design connection would not have been needed, and if WTC were typically framed structures with intermediate columns and beams the drift and motion that occurred after the collisions and fire could have been controlled and the collapse sequences arrested.

As far as building materials go, the design and applications of concrete made it a minor role player in the towers ... floors, and thin floors at that. Once the roof trusses were removed from the dampening equation, the only remaining element left to connect and dampen the motion of the two tubes were the concrete floors ... which, even with rebar and attached to trusses, could not possibly offer adequate tensile strength for that task.

WTC was designed and built in an era and by people who thumbed their noses at accepted practices. They destroyed a vibrant area to acquire land, they went against convention in design, they made elevator passengers change cars to and from their work floors ... and they didn't even have electric light switches. WTC was different in many ways besides design and building materials, it redefined NYC.

[TrogL]

55. An architect friend of mine studied the design

He said that based upon the design as soon as he saw the pictures on TV he knew the building was coming down and wondered why people were sending firefighters into a building about to collapse.

[DulceDecorum]

57. About to collapse

onto its own footprint?

[DulceDecorum]

56. Concrete facts

OudeVanDagen says:
The concrete was an interior design element ... floors ... in a controlled environment of near constant heat and canned air; unexposed to moisture, weather elements, pollutants or wide temp swings. Inside the walls, under carpet, and over insulated ceilings; the concrete floors of WTC were protected against your worrisome destructive forces.

Not so.
The concrete was simply exposed to a slightly different set of destructive forces.

It is very difficult to properly address effect of central heating and air-conditioning on the WTC buildings when we do not know what type of cement was used in it's construction.

Unfortunately, while the knowledge certainly exists to permit the production of concretes with a wide variety of properties, there continue to be a distressing number of concrete failures, due largely to a poor transfer of the existing technology from the laboratory to the field. This is evidenced by the explosive growth in construction-related litigation. At least in North America, ONE UNFORTUNATE CONSEQUENCE HAS BEEN A CONCERTED ATTEMPT TO WATER DOWN EXISTING CODES AND STANDARDS, RATHER THAN TO BASE OUR MATERIAL DESIGNS ON THE UNDERLYING SCIENCE.
http://www.ippt.gov.pl/~abrandt/Mindess.htm

DulceDecorum is apprehensive about the increasingly widespread use of lightweight cellular concrete which may or may not include the use of edible carbohydrates.

Recently, a direction to concrete compositions prepared by using aqueous gels is being considered as all or part of the aggregate in a concrete mix. Aquagel spheres, particles, or pieces are formed from gelatinized starch and added to a matrix. STARCH MODIFIED OR UNMODIFIED SUCH AS WHEAT, CORN, RICE, POTATO OR A COMBINATION OF A MODIFIED OR UNMODIFIED STARCHES ARE EXAMPLES OF AGUEAOUS GELS. A modified starch is a starch that has been modified by hydrolysis or dextrinizaton. Agar is another material that can create a pore or cell in concrete. During the curing process as an aquagel loses moisture, it shrinks and eventually dries up to form a dried bead or particle that is a fraction of the size of the original aquagel in the cell or pore in the concrete. This results in a cellular, lightweight concrete.
http://www.lightconcrete.com/cellular_concrete.htm

Oh YUM, said the concrete weevil.
Ahm aiming to go further and do more
than ma cousin Boll ever dreamed of doin'.
Ahm moving on up, to the Eastside, to a deluxe apartment in the sky.
Howdy thar, Mister Freddy and Miss Fannie,
be sure to pass my regards to the rest of the boys on the NYSE,
and also the Federal Reserve.

The Banker was bad as the Weevils,
Said, There's nothing I can do.
I can't lend you any more money
for the Weevils might eat that too,
And leave it full of holes, all full of holes.
http://nationalhistoryday.org/03_educators/teacher/doc7.htm

This article covers the basics of
beaten, whipped, foamed, fizzy, and therefore cheap, concrete.
http://www.cellular-concrete.com/faq.htm

WARNER: Some of our design and construction practices in the last 30 or 40 years have not been as good as they might have been. Far too little attention has been given to the amount of reinforcing cover concrete and the quality of that concrete. Reliance on the myth that high-strength concrete would automatically provide good durability has also contributed to concrete failure.
http://aec.engr.wisc.edu/resources/rsrc07.html

Reading this article reminded me of the use of High Alumina Cement in building construction. Serious problems have arisen over the years with tower blocks built using High Alumina Cement SUDDENLY COLLAPSING. There is nothing inherently wrong with using High Alumina Cement for construction provided that proper care is taken in the mixing and curing of the cement and good safe buildings could, in theory, be constructed using High Alumina Cement . But in the real world, on building sites, errors do occur which mean that there is always a substantial risk in the use of High Alumina Cement. For this reason its use in construction is banned in the UK. And anyone who has to live in a tower block or travels over a motorway bridge should be grateful for this ban since it protects them from injury.
http://elj.warwick.ac.uk/jilt/compcrim/97_3kelm/kelman.htm

HAC differs from Portland cement, being composed of calcium aluminates rather than calcium silicates. Its rapid strength development made HAC popular for precast concrete in the UK during the 1960s. Mineralogical ‘conversion' however, sometimes caused catastrophic reductions in concrete strength and increased vulnerability to chemical degradation.
Three UK roof collapses in the mid-1970s led to widespread inspection and monitoring of HAC concrete units, exhaustive research and curtailment of HAC use for structural purposes. Sandberg has been closely involved at research, investigative and consultancy levels for more than twenty five years.
A large stock of UK buildings containing HAC concrete remains, in which the HAC is now usually highly converted. Whilst the probability of sudden collapse is now perhaps remote, there is continuing concern over long-term durability, particularly where carbonation has occurred to the depth of steel reinforcement or prestressing wires.
http://www.sandberg.co.uk/labs/f020r05.htm

The staff of CXI has extensive experience in diagnosing all types of deterioration mechanisms occurring in concrete e.g. alkali silica reaction, delayed ettringite formation, external sulfate attack, acid attack and carbonation.
http://www.concrete-experts.com/pages/fama.htm

December 1998
Past experiments have shown that high temperatures significantly weaken HSC. It has higher potential for sudden failure than normal strength concrete when exposed to temperatures of 350 degrees Celsius or higher.
These temperatures are well below the range of a typical building fire, and researchers believe the sudden failure of HSC in fires potentially could trigger catastrophic building collapses. HSC has been gaining in use in recent decades in buildings ranging from the Trump Tower in New York to the Chicago Mercantile Exchange. Designers and building owners favor HSC because it allows the use of smaller beams and columns, resulting in more usable space, lighter structures and lower foundation costs. The results of the NIST study may be incorporated into future building codes to guide designers in the safe use of HSC.
http://www.nist.gov/public_affairs/techbeat/tb9812.htm

[OudeVanDagen]

58. I've been waiting

a long time for somebody ... besides me .... to say this:

The concrete was simply exposed to a slightly different set of destructive forces.

[OudeVanDagen]

59. yes ... we do

we do not know what type of cement was used in it's construction. is categorically untrue. No offense, not attacking ... just being honest; but saying statements over and over again do not make them true, and repeating rumors or something untrue over and over again does not make it true. There are NO secrets about WTC. None, NONE, N-O-N-E!! It is well known, nothing secret at all, about what went into WTC; from the grade and manufacture name of the sheetrock screws to the light ballast to the door knobs to rubber gaskets in the glass frames to the office work modules to the trusses to the parking lot bumpers. It is well known what columns were manufactured when and what days they were erected. It is well known which trucks from what plant delivered the concrete at what hour and on what date and what the slump and cylinder test results were. That's the way Tishman runs work. That's the way things get done at PANYNJ. That's the way things get done in NYC. Come on ....

[DulceDecorum]

60. Then tell us all

exactly WHAT type of cement was used in the construction of the World Trade Center buildings.

Mind sharing the blueprints, while you are at it?
Links please.

[OudeVanDagen]

61. OVD

doesn't do other people's homework ... OVD doesn't do links. If old washed up 80+ year old OVD can find it ... you can too.

[DulceDecorum]

62. Got NUTHIN?

The intrepid hunter of wild geese and snipe returns home from Fresh Kills.
It is Stone Soup tonight, folks.

Most relevant phrase for the post above:
"OVD doesn't do links."

[OudeVanDagen]

63. huh?

from reading ALL your posts it is abundantly clear you ... and YOU especially .... are extremely talented and can very easily find anything you want to find on the info highway. The real question is ... and has been ... do you want to find it?

According to the rules of civilized society it is you who must back your statement "we do not know what kind of concrete was used at WTC" and bear the burden of proof ... not me. You made the statement, now how about the proof.

FYI: I do know what was used. I have ALL the 411; the specs, bids, inspection reports, logs, etc etc from the construction phase. I'll say it again ... if an old washed up 80+ year old like me can find it ... you certainly can too.

I happen to like your posts and the links you offer .... I know you can find anything ... stop bluffing ...

[DulceDecorum]

64. Just listen to yourself:

OudeVanDagen says:
According to the rules of civilized society it is you who must back your statement "we do not know what kind of concrete was used at WTC" and bear the burden of proof ... not me. You made the statement, now how about the proof.

Well now,
isn't that the exact same argument the Bush Administration used to DERAIL Hans Blix?

OudeVanDagen HIMSELF states:
"I know you can find anything"

DulceDecorum has stated plainly:
"we do not know what kind of concrete was used at WTC."

OudeVanDagen is the ONLY ONE who claims to know what type of concrete was used at the WTC.
"FYI: I do know what was used. I have ALL the 411; the specs, bids, inspection reports, logs, etc etc from the construction phase. I'll say it again ... if an old washed up 80+ year old like me can find it ... you certainly can too."

OudeVanDagen,
your bluff has been called.
You have failed to produce.
AS USUAL.

Your credibility is as far gone as that of your naked Emperor
(who has been thrashed by a pretzel)
and his now-abandoned hunt for WMDs.

If you actually HAVE such info,
then how EVIL are you,
to allow the investigation to be derailed
for lack of this particular information?

I am totally disgusted with you.
Who do you work for?
The Port Authority?
SATAN?

[LARED]

65. "we do not know what kind of concrete was used at WTC."

Who is we?

[OudeVanDagen]

67. history is useless

It appears to me very few of the "we" were awake in their history classes. All they gotta do is 'follow the money' ... like in Watergate. They do Watergate in history class don't they?

If "we" wants WTC collapse reports? Just follow the money ... who got grants ... what colleges ... what test labs? If "we" wants to know what went into building WTC? Just follow the money ... look in newspaper archives for the request for bids ... follow the money ... who got what contracts ... what the specs were ... what was delivered. What good is history when it's not being used? I guess history is useless.

Is the government covering up ... hiding that info? "We" thinks so, but "we" isn't using and clicking that mouse right. If that fails "we" can resort to PIA or RTK to find out. PIA ... Public Information Act or RTK ... Right To Know ... BOTH can get "we" anything they want. They're not using it ... very few requests being received. It's easier to point fingers and cry foul than have those fingers do some work. Laws works either as a shield or as a sword. PIA and RTK are swords. What good are laws protecting the publics right to know and giving the public a sword when they're not being used?

I can find things I want and need to know. If I can do it anyone can. Maybe too lazy to look for themseleves ... want instant info without the sweat and legwork. BUT ... OVD believes the real question is; do they really want it ... after all, it will only prove them wrong.

[LARED]

68. You have higher expectations than

I do. I'm still waiting for anyone from the "we" posse to explain why they believe the concrete floors are pertinent to the collapse.

I'll settle for that, before expecting any one to engage in research.

[OudeVanDagen]

69. clues

I believe I have given out enough clues and leads for the serious researcher. What gives? Is it the messenger ... or the message?

Not one person has demonstrated they have familiarized themselves with any pre/post 911 WTC collapse report or litigation which would spell out investigative protocols used. No one has researched the modulus of elasticity of WTC steel and commented on the yield and shear strengths of the columns, trusses, or rebar. Instead they whine on about heat from kerosene fires, destruction of evidence and telescoping wet noodle columns; and then without any research of any kind into collapse sequences, whine on and on about squibs and explosives and black technologies. I am amazed at the number of links offered, yet baffled that no one can find anything they're looking for. I'm even more baffled by repeated catch phrases such as the symmetrical/asymmetrical chant, ignorance of simple collapse terms such as drift, and the boring oft repeated references to 'official story' especially when there are mountains of WTC collapse reports available.

Message or messenger? Probably both; message means research which means work ... yikes! work, forget about that, messenger is an English impaired 80+ old fool marching to a different drummer who has been there and done that and refuses to nod and join the club.

[DulceDecorum]

70. Probably clueless

OudeVanDagen asks:
I believe I have given out enough clues and leads for the serious researcher. What gives? Is it the messenger ... or the message?

OudeVanDagen answers:
Message or messenger? Probably both; message means research which means work ... yikes! work, forget about that, MESSENGER IS AN ENGLISH IMPAIRED 80+ OLD FOOL marching to a different drummer who has been there and done that and refuses to nod and join the club.
http://thinks.com/words/nonsense/william.htm

[LARED]

71. It's the message

Being a conspiracy theorist is a growing form of entertainment for the navel gazing google cowboys of the world.

I know it sounds harsh, but what else can explain it. Being a CT theorist used to take hard work and dedication to the cause. And people knew who you were because in the per-internet days, it was not so easy to act anonymously.

Now anyone can join the club with a click of the mouse and a search engine so the ranks of the so called "investigator" swells. No one know who you are, so you can go to work in the morning and no one know you spend every waking moment scouring the internet for dots to connect in a fantasy world.

That doesn't mean every CT is baseless, as the government is never to be trusted completely, but the 9/11 CT (particularly the demolition fantasy) is just that, a fantasy people can participate in without anyone knowing about it.

[OudeVanDagen]

72. a full time investigation tool

I can't help but notice how 911 investigators active in the airplane threads post and compare photos/images/videos of the 911 planes with photos of non 911 planes. Their investigation tool is comparison ... comparative analysis; that's taking something, in this case standard everyday airplane photos, and comparing them with photos of the 911 planes.

Seems a reasonable process.

If that process ... that investigation tool ... comparative analysis ... is valid and being accepted for aircraft investigation, why do the very same investigators reject it's use for collapse?

Comparative analysis for the collapse (and the following investigation) seems to be avoided like the plague, but it should be employed for the collapse and investigation. Is a recent structural collapse, pick any one; use the Ebenezer Church in Pittsburgh for example, similar to WTC? Yes. True, not exactly, but each experienced extreme events, thermal loads, tension and compressive forces exceeding their modulus of elasticity, venting, and a collapse sounding just like explosions. Each had unique structural elements and connections. One collapse can be compared to the other and better understood. For sure ... the investigation following both these events will be strikingly similar; strict protocols will be followed. Laws of a civilized society demand investigation.

I have stated time and time again that reading other collapse reports would be extremely beneficial to understanding WTC. Comparative analysis is not a part-time investigation tool ... except here.

[OudeVanDagen]

66. LOL

you are hilarious, and thanks for offering that humorous pick me up.

If, IF you're right ... and you're always right .... right? ... the Port Authority built two buildings ... the tallest in the world at the time ... and no one knows what kind of concrete was used. It's been a mystery.

TIP: Hey ... ever read ANY WTC reports? Ever see that "Contact Us" button? If you click and are polite people will give you answers.

[OudeVanDagen]

48. one benefit to world travel

is being able to visit ancient sites where man's use of simple building products have allowed structures to withstand the forces of nature, time and man. To see, touch, smell and feel ... to climb these amazing structures brings great pleasure, but also makes one think what our present civilization will leave behind as it's legacy.

Think about this; the Romans left us Pont duGard, we're leaving the Pulaski Skyway ....

[LARED]

49. Think about this;

The Pont duGard, may outlive the Pulaski Skyway ....

I sometimes get to travel in Europe on business and alway take a day to two to get some site seeing in. I am always awed when walking down the same paths Roman soldiers trod upon, or visiting a building that was built before Columbus even sailed.

Regards

[DulceDecorum]

50. Pyramids, pollution and one person fighting back

Take a look at this site.
It talks about the Great Pyramid of Egypt.
http://www.sacredsites.com/africa/egypt/great_pyramid.html

The Great Pyramid is composed of limestone.
Limestone is a major component of Portland cement.

Today's Portland cement still relies on Aspdin's raw materials for its basic components of calcium, silica, alumina, and iron. The most common combination is limestone, clay, and sand. In today's cement production, minerals from a quarry near the plant are ground to fine powder, then blended to the exact proportions needed for the final cement product.
http://www.geo.msu.edu/geo333/portland_cement.html

Concrete is made by combining cement (containing lime), sand, gravel and water. As these components cure, the water is expelled during dehydration leaving pores in the concrete. It is a comparatively porous mass held together by the embedded steel. The pores set the stage for water and other pollutants to penetrate into the matrix destroying the concrete and corroding the steel. If the liquid pollutant freezes, the expansion will split the mass or spall the surface, weakening and/or destroying the structure. The pores set up a strong capillary action that wicks water and minerals from the ground (up to 20 feet).
The pores and rivulets will act exactly as a sponge reacts near moisture of any type. It will absorb from all directions. Substrate moisture from below, rain from above, standing or running water on any side will be absorbed. As this migration is taking place many other destructive pollutants are being absorbed into the concrete. This wicking process carries all kinds of contaminates with it such as hazardous gases (Radon), odors, sulfate minerals, salts, lime and many other pollutants.
http://www.concreteseal.com/moisture.html

Cover is the distance from the outside face of the concrete to the nearest surface of reinforcing steel.
If this distance is insufficient, the steel will rust. As the steel changes to rust, the diameter of the actual steel decreases and the strength provided by the steel decreases. This can seriously shorten the life of a building and has been a major problem for the Hong Kong Housing Authority.
Furthermore, when steel rusts, it expands to 2.2 times its original volume. This expansion bursts the concrete open thus exposing the steel to attack by the weather which increases the corrosion.
http://www.cityu.edu.hk/CIVCAL/production/traditional/steel_fixing.html

Sulphuric acid is very damaging to concrete since it combines an acid attack and a sulphate attack.
http://www.concrete-experts.com/index.html
http://www.concrete-experts.com/index.html

A eutectic compound is a mixture of two or more substances that melts at the lowest temperature of any mixture of its components. Blacksmiths took advantage of this property by welding over fires of sulfur-rich charcoal, which lowers the melting point of iron. In the World Trade Center fire, the presence of oxygen, sulfur and heat caused iron oxide and iron sulfide to form at the surface of structural steel members. This liquid slag corroded through intergranular channels into the body of the metal, causing severe erosion and a loss of structural integrity.
"The important questions," says Biederman, "are how much sulfur do you need, and where did it come from? The answer could be as simple--and this is scary- as acid rain."
Have environmental pollutants increased the potential for eutectic reactions? "We may have just the inherent conditions in the atmosphere so that a lot of water on a burning building will form sulfuric acid, hydrogen sulfide or hydroxides, and start the eutectic process as the steel heats up," Biederman says. He notes that the sulfur could also have come from contents of the burning buildings, such as rubber or plastics. Another possible culprit is ocean salts, such as sodium sulfate, which is known to catalyze sulfidation reactions on turbine blades of jet engines. "All of these things have to be explored," he says.
http://www.wpi.edu/News/Transformations/2002Spring/steel.html

A pyramidion is another name for an obelisk.
http://members.aol.com/Sokamoto31/obelisk.htm#27list

Cleopatra's Needle, also known as The Obelisk, is located directly west of the Metropolitan Museum of Art on the eastern side of the park near 81st Street. The oldest man-made object in Central Park, by a long shot, is the Obelisk, located directly behind the Metropolitan Museum of Art.
http://www.nynewsday.com/entertainment/nyc-obelisk1,0,127778.photo

Acid rain can be especially damaging to buildings made of limestone and marble. When acid rain falls on the buildings it slowly dissolves away the stonework. For limestone, the acidic water reacts with the calcium to form calcium sulphate:
CaCO3 + H2SO4 = (CaSO4) + 2H+ + CO32-
The calcium sulphate is soluble so it is easily washed away during the next rain storm.
<snip>
Cleopatra's Needle, the stone obelisk that was brought from Egypt to New York has all the hieroglyphic inscriptions on the west side eroded away (the side facing the prevailing winds). There has been more damage done to the obelisk in 90 years in Central Park than in 3500 years when it was on the Nile.
http://www.atmosphere.mpg.de/enid/d7a789442359bf18e5c63439e1b9b042,55a304092d09/100.html

Acid rain is a MAJOR problem in New York.
The pollutants come from the Midwest.
http://www.oag.state.ny.us/press/2000/dec/dec21c_00.html
The struggle to reduce the amount of acid rain in New York has been led by Eliot Spitzer.
http://www.house.gov/boehlert/acid4.htm
http://www.spitzer2006.com/about.html
The new attorney general began looking for cases that mattered. Using an obscure section of the federal Clean Air Act, he took on polluters in the Midwest in 1999, arguing that winds bring their acid rain to New York. Two power companies agreed to pay a total of $2.6 billion to clean up 18 power plants, though the Bush Administration's efforts to gut the act have stalled the cases.
http://www.time.com/time/personoftheyear/2002/poyspitzer4.html

Naturally, the Midwest power companies were unhappy.

The outage occurred quickly and rippled across a large area. Cities affected included New York, Cleveland, Ohio, Detroit, Michigan, and Toronto and Ottawa, Canada.
In just three minutes, starting at 4:10 p.m., 21 power plants shut down, according to Genscape, a company that monitors the output of power plants.
It was unclear what caused the outage, although state and federal officials agreed that it was not terrorism.
http://www.cnn.com/2003/US/08/14/power.outage/

Spitzer has become so popular that even Republicans, including New York Gov. George Pataki, have avoided criticizing him—if only because they don't want to give him any more publicity.
http://www.msnbc.msn.com/id/3770497/

It's painfully clear that Washington will not try to reign in this corruption. Let's hope Spitzer and the new breed of aggressive state attorney generals that are emulating him have the vision and chutzpah to use the full powers of the law to step in where the American federal government has failed so miserably.
http://www.aei.org/news/newsID.19983,filter.economic/news_detail.asp

In conclusion:
New York desperately NEEDS Democrats like Eliot Spitzer,
and so does the rest of the nation,
and the world.

Eliot Spitzer might just be
THE ONE MAN
who can prevent other NYC skyscrapers from collapsing like a pack of cards.

[OudeVanDagen]

51. got two words for ya

Good links ... good narratives ... honest, Scout's honor, good job; but there are two words more worrisome to NYC structures than 'acid rain' and those two words are PIGEON POOP!! No kidding. Those darn pigeon droppings have wreaked multi-million dollar havoc to steel framed structures; Williamsburg Bridge, 59th (Queensboro) Bridge, geez ... you name it and pigeon poop's destroying it. Apologies for getting off thread topic ... good links, enjoyable reading.

[plaguepuppy]

52. Pigeon poop - sounds a little like 'rosebud'

Ya know, at the end of Citizen Caine? One of those deceptively deep sounding phrases the language comes up with. Or maybe 'plastic' in The Graduate...

But seriously, pigeon droppings played an important role in the history of astrophysics. A doctor I used to know was at Bell Labs when the original work on the cosmic background radiation was being done, and knew Arno Penzias. The microwave horns they used were big, and folded as I recall, and at one point some doves made it their home. This kept the experiment from working, and from allowing it to tell if there was a uniform background radiation from the big bang as predicted.

The genius who discovered and evicted the birds (I can't recall if it was Penzias himself) was honored at a banquet and presented with a gold pigeon statue.

[DulceDecorum]

39. Are you saying

that the Romans used magnesium cement?

Are you saying
that the US is NOT experiencing MASSIVE collapse of its concrete infrastructure?

Are you saying
that the CIA had NOTHING whatsoever to do with the entry of those "hijackers?"

Are you doing....an impression....of....William Shatner?

[TrogL]

20. Pulled?

Trying to coin a word here?

There is no reason to tear down a building containing concrete. The office block across the street is solid concrete and it's been there since the 40's.

[OudeVanDagen]

21. forget about it ...

I went to another thread where double D is very active, and asked him to come back here and answer up to his claims. Says he's too busy ... doing "research" .... I say "Where's the beef?"

Hmmm. See posse. See posse run.

[OudeVanDagen]

26. write run hide

The following is from another thread, and is dulcedecorum's response to my request that he follow-up on his concrete theory ... or whatever it is:

Quote: Allow me to explain how this thing works.

Democratic Underground has several forums.
The forums are arranged according to subject.
You choose the subject that interests you and you visit that Forum.
On the forum you will find several different threads.
Each thread is a conversation where people are talking about one particular topic.
NOW PAY ATTENTION TO THIS PART, OudeVanDagen.

You are welcome to join in the conversation
BUT
please do not try to side-track it.
If you do then you are a disruptor.
If you disrupt,
and most especially if you disrupt poorly,
then you will, OudeVanDagen,
receive a special award from the Democratic Underground.

Mr. OudeVanDagen,
we are NOT discussing cement on this thread.
If you want to discuss cement,
then by all means either open up a new thread
OR
return to the thread where cement was mentioned and post there.
And now Mr. OudeVanDagen
PLEASE HUSH UP
and let people talk about LIHOP and inviting terrorists over into the US." end quote.

Q: Why did doubleD spend so much time writing that lengthy response when all he had to do was click on this thread and simply .... very simply .... answer the questions?
A: He has no answers.

See the posse. See the posse write. See the posse run. See the posse hide.

[LARED]

22. The history of concrete

1891 George Bartholomew placed the first concrete street in the USA in Bellefontaine, OH. It still exists today!

http://matse1.mse.uiuc.edu/~tw/concrete/hist.html

[el_gato]

9. I think there is some video of it online I will try to find a link

[el_gato]

11. here is one view

http://www.wtc7.net/docs/wtc7_collapse2.mpg

The building looks rather unscathed prior to falling down.

[Az]

12. Yep

And I see smoke billowing out of the building. I see one side of the building. I do not see the inside of the building. The smoke is indicitive of fire burning. An explosion would not have such billowing smoke.

Seems to confirm to me collapse due to damage and fire.

[el_gato]

13. Wrong

there is smoke behind the building as there was all around the WTC complex but you cannot see smoke billowing out of the building

as well I do not see any broken windows or debri all over the building

Perhaps you could argue it was due to foundation damage but even burning buildings don't just magically implode like that

[Az]

15. Just reporting what I saw

A building whose infrastructure gave out. Smoke from fires burning inside billowed out. It was not a forced fireball as I would expect from a blast. It was not a sequence of explosions proceding down the structure. It appears to be smoke from an existing fire.

Your evidence is unconvincing. We can argue back and forth about what it means but I have explained what I see in the picture. If you have other evidence I am certainly open to it but so far you have not proven your case.

Do not mitake me for someone defending George. I would love to see him drawn and quartered. I believe he and the right wing have set us on the road to ruin. I just do not see what you claim to see. I suspect it is a belief issue and do not suspect I can convince you otherwise.

[TrogL]

14. This has been well covered in other threads

Firemen on the scene noted that the building was so badly damaged that they refused to go into it because it was in danger of imminent collapse.

[DoYouEverWonder]

16. Do you have a link for that?

I don't think anyone expected WTC7 to collapse.

The reasons I've heard, were that they didn't have the resources to try to put out the fire in WTC7 and the building had been evacuated hours earlier. Most of the effort was focused on rescuing people from you were thought to still be alive under 1 & 2.

[LARED]

17. Link

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=125x8288

[DulceDecorum]

29. Sympathy strike

It was a card-carrying member of that union.
Or maybe, its collapse was due in part to brisance.

[plaguepuppy]

41. wTc and sympathy

Or maybe it had survivor guilt...