puddle welds and corrosion

huangyhg

puddle welds and corrosion
the deck is 22 gage corrugated galvanized steel deck supported on galvanized steel tubes. the deck is connected to the support members with 5/8" puddle welds with whashers. the deck is near the bay (corrosive environment).
how is the weld protected against corrosion? (i.e. the are on the galvanized support member where the weld is, how can that area be protected ?)
thank you
v2
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typically the weld areas are wire brushed and coated with cold galvanize
the weld area is not accessable. it is between the underside of the deck and the top of the galvanized support   
given the above information, should i be concerned about corrosion at the weld vecinity of the weld between the underside of the deck and the top of the galvanized hss support?
thank you
v2
i am assuming this is an enclosed building.  if so, i would not worry about internal corrosion of the welds, even in proximity to the bay.  external application would be an issue.  in that case, spray each weld area from the underside as boo1 indicated.
i like to make two comments here:
1. deck that is 22 gage, in my opinion, is too light to weld. i have designed many square miles of metal roofs. i do not use ant thing but type b deck and 20 gage (required or not). you should see a metal deck after sloppy welders are done with it. washers will help; but welders do not like to use them and you almost have to be there all the time to ensure that they are being used.
2. i am a fan of mechanically fastened deck as well. if your uplift and diaphragm loads can be accommodated by tek screws, use it. sdi manual and hand book, by dr. larry luttrel, phd, p.e. has very good shear tables for mechanically fastened steel deck.
i hope this helps.
lutfi