It needs to allow for ground conditions, the weight of the bin full with the heaviest material that it could conceivably hold, plus the loaded weight of the heaviest vehicle adjacent to it and standing on the same slab. Oh, plus a little reinforcing bar.
Civil Engineers are good at these sort of calculations.
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The elephant is a funny bird. It flits from bough to bough. It lays its eggs in a rhubarb tree and whistles, like a cow - Spike Milligan.
Northern wisconsin grain bin
