Griffin writes, "in fire-induced collapses---if we had any examples of such---the onset would be gradual. Horizontal beams and trusses would begin to sag; vertical columns, if subjected to strong forces, would begin to bend. But as videos of the towers show, there were no signs of bending or sagging, even on the floors just above the damage caused by the impact of the planes." But contrary to what Griffin claims, there were indeed signs of bending or sagging. Witnesses reported it and photos document it. Griffin is simply wrong.
Griffin erroneously writes "The buildings were perfectly motionless up to the moment they began their collapse." The fact is, before the collapse of either tower, evidence the structures of the WTC were failing, columns bending, floors sagging, was reported by Police, Firemen and civilians. We can see in the photos that the exterior columns were bowing in the minutes before the collapse, in the case of the South Tower, the bending was evident as early as 18 minutes after the plane's impact.
Griffin writes, "In controlled demolition, the onset of the collapse is sudden. One moment, the building is perfectly motionless; the next moment, it suddenly begins to collapse." But the buildings did not suddenly collapse without any indications. Instead, exterior columns buckled because the fires weakened the floor trusses and the floors sagged. The sagging floors pulled on intact column connections so as the floors sagged down, they pulled the exterior columns inward. This inward bowing of the exterior columns was evident to observers such as the police helicopters circling the towers.
"While the buildings were able to withstand the initial impact of the aircraft, the resulting fires that spread through the towers weakened support columns and floors that had fireproofing dislodged by the impacts. This eventually led to collapse as the perimeter columns were pulled inward by the sagging floors and buckled." "The reason the towers collapsed is because the fireproofing was dislodged," according to Sunder. If the fireproofing had remained in place, Sunder said, the fires would have burned out and moved on without weakening key elements to the point of structural collapse." - Bowing Debunks Explosives
WTC photos show buckling steel columns in the minutes before the collapse of the buildings.
See Controlled Demolition Debunked
see previous post for debunking of WTC 7 claims
UPDATE: Just added the following to the video info of my video "Facts "9/11 Skeptics" don't want you to see: REAL 911 Truth":
Griffin also makes the mistake of quoting Kevin Ryan who concocted the idea that one of the tests designed to estimate the fire rating of the floor assemblies as they were built was done in order to provide data to input into the fire response model. Griffin and Kevin Ryan are wrong. See page 50 of "On Debunking 9/11 Debunking, Examining Dr. David Ray Griffin's Latest Criticism of the NISTWorld Trade Center Investigation" by Ryan Mackey "Because this test was subscale and represented an undamaged floor assembly, we should not expect floor deflection in the WTC Towers, both larger and with damaged fireproofing, to be the same. Thus, the WTC Tower floors would not be expected to sag only 3 inches." "We have now demonstrated that the NIST models do not rely upon unsupported "tweaking" of models. Rather, Dr. Griffin and his colleagues are mistaken about the sources of information used to develop those models. As a result, Dr. Griffin's charge, that the NIST model conclusions result from circular reasoning, is incorrect." (pp. 50-51)