[randog]

...once the first gusset plate fractured, the rest would have failed as the weight of the bridge shifted and generated momentum.

Impossible. The 9-11 Truthers and Experts assure me that steel must become molten before it loses its tensile strength and collapses.

</sarcasm>

[17th Miss Regt]

steel must become molten before it loses its tensile strength and collapses.

...and as we all know, fire has never melted steel. (R. O'donnell, PhD, Structural Engineering and Donut Consumption)