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Old 1st May 2008, 09:49 AM   #316
Join Date: Apr 2008
Posts: 470
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OK people, I don't recall this coming up before on this website but I am one of those insane people that gets called a tinfoiler and is incapable of believing that an airliner could knock down a WTC tower in less than 2 hours on 9/11, much less two of them.

In an exchange on another site someone brought up a link to an EXPERT that is so dumb I just had to share it. So far my google searches have not turned up anyone else pointing out this stupidity and I find that somewhat shocking. So let's see if anyone here can point out something wrong with my reasoning.

This is an exchange about the grammar school physics of the collapse.

Apparently the experts can get away with really dumb mistakes.

============== First Post by Lurid Larry ================

Maybe with psikeyhacker and "many others" but not with engineers.

When you care enough to read the very best.


By F. R. Greening

www (dot)

Lurid Larry

=============== Firsst Response by Me =================

Greenings report is here:

www (dot)

[That link has changed but it had the same info as the previous one]

On page 3 it says this:

For the general case of n floors collapsing we define a collapsing mass Me:

Me = n m(f) ............................(1)

where m(f) is the mass of one WTC floor, assumed to be 1/110 the entire mass of an entire WTC tower, namely m(f) = (510,000,000 / 110)kg = 4,636,000 kg.
Now the World Trade Center was 116 stories tall. The foundation was sunk into bedrock which was necessary for a building that tall and massive and there were 6 basements. So when people quote figures for the mass of the building are those levels included or not? Every floor of that building had to be strong enough to hold the weight of all the floors above. Do you really believe the fourth floor weighed the same amount as the 99th floor? Didn't the fourth floor have to hold a little bit more weight than the 99th floor? If you check the NIST report you will find that 14 grades of steel were specified for the columns of the outer perimeter of the building though only 12 were used. The steel got thinner as you went up the building.

So the bottom of the building must have been much heavier than the top and assuming an even distribution is total nonsense. This is why I keep demanding a specification for the quantity of steel and concrete for every floor including the sub-basements.

Why don't you check out the NIST reports yourself Lurid Larry.

Some people need experts ... to tell them what to think.


== Next Response by me skipping a couple by LL that weren't informative ==

Originally Posted by Lurid Larry
If you have a problem with the data, I suggest you do some research.

Lurid Larry
I had already done it, but I think about the research I do not just believe it. Here are some thoughts about yours, maybe you can handle blocks.

Suppose we do some simplified collapse calculations with 3 sets of blocks to get some basic principles settled. The blocks are all 1 unit on the side. Two stacks of blocks are made with sequentially wieghted cubes that weigh 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 pounds each. One stack is built with the heaviest toward the bottom and the other with the heaviest toward the top. These stacks weigh 66 pounds so the average is 6 pounds therefore the third stack is built with 11, 6 pound blocks.

Fall distance     Btm Hvy     Top Hvy     Avg
    10               1           11        6
     9               2           10        6
     8               3            9        6
     7               4            8        6
     6               5            7        6
     5               6            6        6
     4               7            5        6
     3               8            4        6
     2               9            3        6
     1              10             2        6
     0              11             1        6
                    220          440    330
Multiplying the distance fallen times the weight of the block and adding that for all of the blocks in the stack yields 220 for the bottom heavy stack. The top heavy stack is double that amount and the average is right in the middle as expected. But what tall building is going to be built top heavy? And the average stack is 50% higher than the bottom heavy arrangement. Would you want to go into a building designed by supposed engineer that tolerated a 50% error?

Now since I am using 11 blocks and the WTC was 110 stories then 1 of my blocks is representative of 10 floors of the WTC. Your engineer talks about the mass of the top 30 stories so that must mean the south tower and equivalent to my top 3 blocks. The top 3 in the bottom heavy case have a total mass of 6, but the top 3 in the averaged case have a total mass of 18. So if the WTC was in fact bottom heavy then the data your engineer is working with could be way off even if his equations for collapse energy are correct because he is assuming too much mass toward the top.

So what about the bottom heavy case with basements.

Fall distance     Btm Hvy
        10             1   
          9            2   
          8            3   
          7            4   
          6            5   
          5            6   
          4            7   
          3            8   
          2            9   
          1           10   
          0           11   
          0           12    underground sub-basements
If you dig a hole and and put in a 12 pound block and stack the 66 pounds of blocks on top then the total mass is 78. 78 divided by 12 is 6.5 but 78 divided by 11 is 7.1. So if the sub-basements are included in the total mass of the building but you only divide by the floors above ground level then the mass of the top 30 floors are exaggerated even more. If that was the engineer's intent then what he did made sense. So the people that "want" to believe that conclusion get their confirmation from AUTHORITY with correct mathematics that looks impressive but based on fundamentally FLAWED ASSUMPTIONS.

At this government link on PDF page 84:

NIST can't be wrong!


The following paragraph specifies the company that made the perimeter columns and the various "ksi" specs for those columns. That "ksi" means 1,000 pounds per square inch. The columns ranged from 36 to 100 ksi and 12 different grades were used in the WTC. Don't you think a 100 ksi column weighed more than a 35 ksi column? Don't you think the heavier columns were used toward the bottom of the building?

So what is the story with this "very best" engineer using the average of all of the above ground floors on a 110 story building and ignoring the sub-basements and not saying the the building had to be bottom heavy and using that average to calculate collapse energy?

Now I am just using these blocks to demonstrate how a bottom heavy mass distribution changes the results. Why can't the EXPERTS tell us the tons of steel and tons of concrete one each floor of a building designed in the 1960's six years after its collapse? Now this is some very simple physics presented without all of the mathematical complexity that Mr. Greening seems to be prone to but that is usually the type of style one has to use to be taken seriously by fellow professionals. But how can he possibly make mistakes that dumb? Is he being payed to produce an obfuscating smoke screen? I don't care. This is simple physics and it shouldn't be difficult for most people to see the distribution of mass must be important to the solution. How can the country that put men on the moon be discombobulated by this trivial junk?

================ The End ====================

FR Greening is a Canadian chemist. What is a chemist doing getting media time if he is talking about the energy of collapsing masses?

Any comments?

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