[Darksheare]

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/04/29/BAGVOPHQU46.DTL

http://www.landlinemag.com/todays_news/Daily/2004/Oct04/101804/102204-02.html

[editor-surveyor]

In both of those incidents, the fuel was gasoline which burns at rougghly twice the temp of jet fuel. Also in each the was a free flow of air allowing complete combustion .

In the Oakland incident the bridge was not steel, it was steel reinforced concrete, where the heat spalled the concrete (this can happen at much lower temps than were occurring) and annealed the steel reinforcing rods. The fire also involved burning asphalt concrete.

I don’t know the structural details of the Birmingham bridge, nor the height of the bridge above the fire, but I suspect that it would have been similar.