Column baseplate painting/corrosion inhibition

[TheFeds]

I'm preparing a design for a column baseplate (1/2" thick ASTM A572 Grade 50), and need to determine whether there is any great risk of corrosion due to water seeping between the base plate and the grout bed upon which it will rest. Other columns which were installed in crude fashion exhibit significant rust, which we'd like to avoid, this time around.

Should the bottom of the plate be painted, and if so, with primer only, or primer + finish coat? (Primer is alkyd, topcoat is alkyd enamel.)

The facility is, for all intents and purposes outdoors (and it may be exposed to road salt, snow and water).

 

[jike]

If the base plate is exposed, then you might want to locate the top of pier high enough to keep away from the majority of water and road salt. You might consider sloping the concrete away from the base plate to promote drainage.

I would primer and finish coat the base plate. You might consider galvanizing the plate.

I am a little surprised that you are using Grade 50 instead of Grade 36. Thinner material will have less longevity when it comes to corrosion.

 

[dik]

Can you use a bitumen type of coating/mastic on the assembly below grade? or a zinc rich primer? It is also possible to hot dip galvanize just the base, although pricey.

Dik