Pallet Jack and Racks on Wood Floor System? 1

[XR250]

I have a customer who recently purchased a one story building with a wood floor system. It has a crawlspace below. They want to use it as storage for canned food and dry goods. They asked me if I could determine if this was possible. They plan on having pallet racking and use a pallet jack to move goods from the delivery trucks. I have not been to the job site yet but my first thought was to tell him to remove the wood flooring in the storage area, build an interior masonry foundation, fill it with washed stone and pour a slab.
Other than trying (and ultimately failing) to enforce limits on how much load can be in certain areas do you feel like there are other options? They were amenable to adding dropped girders and additional layers of subfloor.

Thanks

 

[Ron]

Since storage racks tend to place high shear loads on the flooring, you might consider some simple sleepers to spread this out. Pay close attention to the orientation of the sleepers relative to the joists.

 

[XR250]

Ron? Blast from the past
I was thinking of welding a tube steel beam to the legs of the racking as a distribution member. I imagine i can get the racking to work out - not sure about the pallet jack though.

 

[EngineeringEric]

not sure the state of it all but maybe adding a second layer of 1-1/8" sheathing would help, or possibly a 3/4"-1.5" layer of gypcrete/LW cementitious float??

The moving jacks feel like the biggest hurdle. excluding racks parallel to the floor-joist system before you reinforce that

 

[jayrod12]

We've seen wood framed floors for loading up to 500 PSF on some Northern grocery stores. And by Northern I mean Nunavut and Northwest Territories. In those instances it's 3" T&G decking on tightly spaced joists.

 

[XR250]

Just checked it out. Tall crawlspace so slab is likely out. 2x10 @ 16" o.c. spanning about 10 ft w/ 3/4" diag sheathing and 3/4" hardwood.
Maybe reinforce the framing and add some steel plate to keep the wheels from punching thru?

 

[jayrod12]

Add joists in each space to bring the spacing down to 8" o/c? I'd be surprised if 3/4" sheathing had an issue with any magnitude of load when only spanning 8"

 

[XR250]

That's a good idea

 

[jayrod12]

Something about a blind squirrel and finding nuts. It's bound to happen sooner or later.

 

[milkshakelake]

Add another layer of very thick plywood. Add a sheet of asphalt paper or something compressible on top of the plywood deck. Then add 1/4" steel plates 4'x8' screwed into the plywood deck. The steel plates should be screwed so they don't move around, maybe something like 12 screws per plate (with pre-drilled holes). The compressible layer is so that the edges of the steel plates don't punch into the plywood.

The pic below shows this approach (with diagonal planks instead of plywood). The only issue is that the steel plates weren't screwed in, so they moved around. The asphalt paper was put between the planks, which doesn't make sense to me.

As for the framing, you know what to do; just standard reinforcement, sistering joists, possibly shortening the spans with supports/beams/columns/foundations, bridging, etc.