Probably The worst Towers Ever Constructed, page 1

Rotator,

There's an enormous elephant lurking in the premise of your post. You forgot to mention the core of the towers. I'm sure it was an oversight.

The external columns were not the primary load-bearing structure of the towers; the 47 columns of the central core was.

The external columns provide stability and flexion, but do little to hold up the actual structure. This is why the pancake theory is laughable; you'd still have the massive core left standing like a spindle and a stack of old LPs.

BTW, here's what the core looked like:

files.abovetopsecret.com...

Construction plans have purposely been withheld from the public so that the the misconception has arisen that the exterior columns actually bore the weight of the structures. Not so:

The core columns were steel box-columns that were continuous for their entire height, going from their bedrock anchors in the sub-basements to near the towers' tops, where they transitioned to H-beams. Apparently the box columns, more than 1000 feet long, were built as the towers rose by welding together sections several stories tall. The sections were fabricated by mills in Japan that were uniquely equipped to produce the large pieces. 2

Some of the core columns apparently had outside dimensions of 36 inches by 16 inches. Others had larger dimensions, measuring 52 inches by 22 inches. 3 The core columns were oriented so that their longer dimensions were perpendicular to the core structures' longer, 133-foot-wide sides. Construction photographs found at the Skyscraper Museum in New York City indicate that the outermost rows of core columns on the cores' longer sides were of the larger dimensions. Both the FEMA's World Trade Center Building Performance Study and the NIST's Draft Report on the Twin Towers fail to disclose the dimensions of the core columns, and the NIST Report implies that only the four core columns on each core's corners had larger dimensions.

Like the perimeter columns -- and like steel columns in all tall buildings -- the thickness of the steel in the core columns tapered from bottom to top. Near the bottoms of the towers the steel was four inches thick, whereas near the tops it may have been as little as 1/4th inch thick. The top figure in the illustration to the right is a cross-section of one of the smaller core columns from about half-way up a tower, where the steel was about two inches thick. The bottom figure shows the base of one of the larger core columns, where the steel was five inches thick. The bases of the columns also had slabs of steel running through their centers, making them almost solid.

More about the core they want you to forget here.

Mod Edit: Image Size – Please Review This Link.

[edit on 25/3/2007 by Mirthful Me]

[edit on 25-3-2007 by gottago]

[edit on 25-3-2007 by gottago]