Better check again. A skyscraper not only has to support the weight of the people and objects inside of it, but IT'S OWN WEIGHT AS WELL. (experts calculate the weight of the WTC towers at around 500,000 TONS)
A 100 story skyscraper is exponentially heavier than a 20 ft tall, 30ft long highway overpass.
Highway overpasses are constructed of steel REINFORCED concrete. They are not constructed of solid steel.
Around here they are mainly steel I beam construction as they are old. The concrete goes on top. And they are more like 100' long or more.
I don't know why I need to explain something so simple but evidently I do.
The question is not which is designed to hold more of its own weight, the question is what is designed to hold more ADDITIONAL force.
Also, a building distributes the weight straight down. The center of mass is directly over its base. A freeway overpass is designed to support weight along its span. This little fact of physics means that the overpass must be capable of loads a building would never see.
Think of an 8' 2X4. Will it hold more weight when placed on its end like a table leg or when laid flat spanning two objects with the weight on the center?
Compared to an overpass, a skyscraper is downright fragile. But regardless of which is stronger, the fact is fire did weaken the steel sufficiently to cause it to collapse under nothing but its own weight. This blows the "fire not hot enough" theory out of the water.
I checked back to page 38 and while this point was brought up it was never refuted. The one guy did say that everything had been debunked but never showed anything to support that claim.
Bottom like, the steel in the WTC would lose at least 60% or more of its strength at the estimated temperatures. Why is it difficult to see how a building hit by a jumbo jet and losing more than 60% of its strength would collapse? BTW, at 40% strength steel will sag under its own weight.