It looks like it could be a bulkhead with filter elements of some sorts. Maybe osmotic desalination of water? Uranium enrichment through diffusion?
Or maybe a top cover of nuclear reactor?
Looks almost like a jig roller system? These typically have rollers that come up out of the table to enable jjig movement and than drop down to allow the jig to drop to the table, the centre looks like an open frame motor of some kind.
Max.
Looks like a Cargo bay deck of an aircraft for rolling in and out cargo. Actually can almost guarantee this is what it is or possibly the cargo bay of a ship. Most likely aircraft though