Wood Blocking under Steel Columns in Freezer Structure
Wood Blocking under Steel Columns in Freezer Structure
(OP)
I am trying to find an alternative to the oak wood blocking or poly bocking that we use between the baseplates of steel columns and concrete footings as a thermal break in food freezer structures. These two methods have become long lead time items or too expensive.






RE: Wood Blocking under Steel Columns in Freezer Structure
RE: Wood Blocking under Steel Columns in Freezer Structure
RE: Wood Blocking under Steel Columns in Freezer Structure
RE: Wood Blocking under Steel Columns in Freezer Structure
RE: Wood Blocking under Steel Columns in Freezer Structure
If the heating system is not in place yet, see if additional heating can be provided over the footing. Talk with the heating system designer about this. You don't want to provide too much heat. Also, be sure to provide a good separation between the column and floor slab. 1/2" insulation min. This is to help prevent sweating and freezing of water on the floor slab.
My suggestion, remove 2" of the top surface of the footing under the base plate and place the blocking there. Second option would be the additional heating I talked about above.
Hope this helps.
RE: Wood Blocking under Steel Columns in Freezer Structure
By the way, how would you calculate the heave force? I assume the column area transmits the cold into the footing and then into the ground. What is the area influenced by that one column trnsmiyying that cold into the ground? It seems there would be some limit to the amount of cold that can be transmitted. It wouldn't seem likely for that column to freeze soil 15 feet away.
RE: Wood Blocking under Steel Columns in Freezer Structure
RE: Wood Blocking under Steel Columns in Freezer Structure
You are correct: there is a limit to the amount of freezing that can occur. Some of the critical variables include the BTU rating of the freezer, the "average" ground temperature, the soil types(s) and profile, the soil moisture contents, depth to "the" groundwater table, and foundation type(s) / depths / geometry. That question is far too complicated to answer on this forum; you need to retain the services of a geotechnical engineer with relevant experience to answer that question (after s/he performs a proper field exploration and lab testing program, of course.)
And freezing to depths/distances in excess of 21 feet doesn't sound excessive to me. I've seen far stranger things happen...
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