on what kind of factory it was and what it built and where in the factory,,,poured and reinforced concrete will obviously hold up better under laid brick cobbles etc etc. Though brick cobbles laid side up are pretty tough. I shot in the new(ish) GM Tonawanda Engine plant (Buffalo NY) the day they poured the floor for the new factory and due to the weight of the machines going into the space the reinforced concrete was being poured to over 3' deep. watching the process was like a disney movie for guys who love the how-to stuff (me:)
I've shot in many WWII (US) and before era factories, I know for a fact that they did war work on different scales, and the floor(s) in each varied even with-in the same factory. I've seen reinforced concrete, most prevalent, stone cobbles, brick cobbles (several layers deep) and most interesting were floors mad of "bricks" made of oak I think. They are cut from like 6" x 6' studs, about 6"-8" long and laid end up side to side to side no filler/mastic that I could ever see. My assumption is that they were used where all chances of sparking could be alleviated. In addition they would maybe last longer than other materials and could be easily fixed when worn, easier than replacing an entire concrete pad.
I've also seen loading ramps that were made of laid long log lengths 12" x 12" sq stuff.
I have two recommendations 1. there are LOTS of German factory shots available from WWII, factory and yard shots-look at the backgrounds not the tanks:)
you'll see the floors just fine-I saw mostly reinforced concrete when i looked, at least in the tank factory pics
2. If you're having trouble coming up with a final answer go with your "gut" because who's gonna argue with you?
:)By the time you're done trying to figure it out you'll be the closest we have to a German WWII factory floor-composition guy:)
My2cbobC
