question re. Weathering Steel for bridge-design

[KnarfMan]

Was wondering if "weathering steel" (Gr.50W) is available in standard rolled wide-flange shapes? If so, can someone supply any information as to section availability? Any websites, links or company contact #'s would be appreciated.
Thanks in Advance (TIA)

 

[HgTX]

Yes, it is available from most mills that produce structural steel. Look for ASTM A 588 or ASTM A 709 Gr. 50W.

Hg

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[Qshake]

If you are in the US you can check with the National Steel Bridge Alliance for more information. They will have links to sites that will give you availability.

Look them up using any web browser.

They are a subset of AISC.

Regards,
Qshake

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[HgTX]

Correction to what I said before (I didn't read your post thoroughly enough)--for bridges, it would only be A 709 Gr. 50W (or higher "W" grades), not A 588.

Also check out this guide for detailing to avoid staining your abutments & piers:

http://www.steel.org/AM/Template.cfm?Section=Bridges1&CONTENTID=8977&TEMPLATE=/CM/ContentDisplay.cfm

One postscript to that report, though--they found that wrapping the piers was not cost-effective. On the project they tried it on, they ended up giving up and just cleaning off the concrete instead once the deck was poured.

Even with proper detailing to avoid staining, many states still need to paint the ends of the WS girders to protect them from water and salt coming through the bridge joints. What some states have done to avoid problems with color matching (it's really hard to find the right color; depending on where you are, the WS will weather to anywhere from orange to chocolate brown) is to paint the fascia girders. Here in Texas we don't use much road salt, and our WS bridges are happy with no paint anywhere.

Hg

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[MichSt]

I strongly recommend talking to some fabricators in your area on steel availability and lead time if schedule is an issue on your project. I’ve been recently told by fabricators (in the mid-west) lead times are 4-months +.

By the way, in Michigan we no longer use bare weathering steel for bridges due to the issues noted above by HgTX. It can still be used if the contractor opts to but it has to be completely painted like non-weather steel.

 

[Qshake]

Also many DOT's have criteria for when you can use WS and when not too.

For example, some states will not let you use WS steel for overpasses that are less than 17' over the road due to the salty spray generated vehicles.



Regards,
Qshake

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