Introduction Of Heiwa, Planes should not collide with towers Options

[Heiwa]

Hi all. I am Heiwa. Naval architect. Designing ships since 40 years. Quite complex! Lots of forces acting on a ship structure in the interface water/air affecting strength, buoyancy and stability. Like planes. Structures fixed on land are easier to design. Take a tower/skyscraper:

A tower/skyscraper structure consists generally of load carrying elements of only two types, i.e. vertical steel columns and horizontal composite steel/concrete floor panels, all joined together one way or another, e.g. by bolts.

The vertical elements, the columns, joined on top of each other are primary structural elements that transmit their loads down to ground.

The horizontal elements, the floor panels, placed between and connected to the columns are secondary structural elements that transmit their loads to the columns.

And that’s it. Nothing magic at all! Not like a ship or a plane.

If a skyscraper has 110 floors, like WTC, there are thus 110 assemblies of horizontal floor panels all connected to the vertical columns. Evidently the columns between ground and the first floor are designed to carry 110 floors and the columns below the top floor (or roof) are designed to carry just one floor (or the roof).

It means that the lowermost columns of a tower structure are 110 times stronger than the topmost columns.

Airplane pilots are highly recommended not to fly their planes into towers/skyscrapers, as the vertical and horizontal elements of the towers/skyscrapers will slice/shred the plane into small pieces. Evidently the plane will cause some local damage to the structural elements of the tower or skyscraper … but that’'s it.

Anyone believing that flying planes into the weak tops of skyscrapers will destroy or crush the strong bottom parts of same towers should read my scientific paper at http://heiwaco.tripod.com/tower.htm . I am happy to inform that you can in fact fly as many planes you like into the tops of skyscrapers and nothing will happen to skyscraper below impact. The plane's pilot will evidently get smashed.

If you belong to a terrorist organization and plan a flying attack anywhere you should thus avoid flying planes sideways into the weak tops of skyscrapers as you will only produce local failures up in the weak top and kill yourself. Better is to hit the bottoms or Stuka style vertically through the roof. But you will still kill yourself.

I have informed the FBI and CIA about the above and they, Pearl Harbour style, informed that couldn’t care less, I was sorry to hear. They apparently have great difficulties in Afghanistan forgetting the home front. Well, do not blame me.

This post has been edited by Heiwa: Nov 5 2011, 01:38 PM

[SanderO]

Anders...

Let see...Go to any load table for the components of the composite. You know that the load tables which you may use in your own work were determined with empirical testing.

A section of steel which has an ASTM A36 designation has a minimum yield strength of 36,000 psi. A36 steel is made to spec with a specific set of additive metals to the alloy.

The same applies to the concrete used for the floor slabs. The strength is determined by the admixtures, the amount of water, the time of curing, the type and amount of aggregate and reinforcing for tensile stress with steel... wire mesh or rebars if required.

Concrete used in construction is sampled both at the time of pour and after curing for testing. One is a slump test at pour time and the other is a cylinder which is then subject to compression testing.

The WTC floor concrete floors outside the core was designed to support minimum 58 psf. This was a 42% strength reduction negotiated by PONY, with LERA, and the NYC DOB which as a code requirement of 100 psf. The strength reduction applied to the ENTIRE composite... not JUST the concrete.

As you may know a composite is only as strong as its weakest component. Under stress, the weakest element fails first... and this may or may not result in failure of the other components. If the trusses were to fail first.. it is unlikely that the floor slabs would not shatter and fracture. On the other hand it is possible for the concrete to be shattered... and the trusses to remain. After all the trusses were self supporting before the concrete was poured.

The floor system at the twin towers likely experience progressive... top to bottom failure - shattering, fracturing, crushing, grinding and pulverization from mechanical interactions.. millions of them in a very short span of time.. turning the 4" slabs to sand sized particles and dust.

I'll split the $1,000,000 prize with a worthy cause like OWS... Thank you.