11 сентября 2001   ::   Мейссан Тьерри

The total per floor volume of steel, isnow the sum of that in the perimeter wall, the central core section and the floor system. This is 563 + 1210 + 477 = 2250 cubic feet.

So why have we gone to all this trouble to calculate the per floor volume of steel? Well, we know that 96,000 tons of steel was used in the construction of each of the WTC towers. The WTC towers had 117 floors (110 above and 7 below the Plaza level) so an average floor contained 96,000/117 = 820 tons of steel. Since the density of steel is 490 pounds per cubic foot, we see that each floor contained about 820 x 2000/490 = 3347 cubic feet of steel.

Now, according to the above calculations, the per floor volume of steel in each of the towers, is (a very generous) 2250 cubic feet. But this is only 67 percent of the volume of steel that we know was used in the construction of the tower. So, the big question is: Where is the other 33 percent? Where are the missing 32,000 tons of steel? What features of the building are being left out of the «official» explanations?

Could it be that each concrete floor was actually supported by weighty steel beams and not by the very flimsy trusses of the «official» story?

Well, the following picture, taken during the construction of the WTC, may hold the answer.

Here, one can see what appear to be large steel girders laid out according to the plan for the positioning of the supposed double trusses (this plan is pictured here). To make things clearer, the position of the girders have been marked in white in the photo below. Remember, that the perimeter columns which appear like a row of toothpicks in the visible sections of the wall, are actually 14 inches wide. Thus the floor joists do indeed appear to be quite large steel girders. One thing is certain though, they are not the claimed double trusses.

In this photo the vertical red lines correspond to visible core columns. The white lines (apart from the outer perimeter lines) correspond to visible floor joists.

Above, is a photo of early construction work on the South Tower. Behind, is the North Tower and further back, the Verizon building. The photo was taken from the old extention of Greenwich Street (which was ripped up to make way for WTCs 4 and 5) looking north west. Some interesting aspects of the construction are presented in the following enlargements of the red-boxed regions.

In this enlargement one can see eight perimeter box columns at ten foot intervals (further up the structure these columns split into three smaller box columns at 40 inch intervals).