Truss cost estimates

[bridgeDisciple]

I currently have a very light weight (less than pedestrian) modular steel bridge design. I'm trying to estimate its constructed cost, and could use your help/experience.

The bridge module comes in at just under 100 plf (pounds/linear foot). Steel is currently going for about $666/ton = $0.33/lb. Structural shapes are going for about $2.60/lb, except for angle which is about half that. But i don't know what constructed trusses are going for. The module should be produced in large volume, so i expect heavily robotic manufacture. I think open web steel joists are probably a good model (about same ratio of weld joint length to member length; also large volume).

Anyone able to share the going rate for open web joists ($/lb)?

 

[BridgeSmith]

We're seeing bid prices in the range of $4.00 lb for the structural steel for welded plate girder highway bridges; slightly less, maybe $3.50 for the steel for wide flange girder bridges. Of course, we're dealing in large quantities (100,000 lbs and up), but that includes erecting the steel, also.