I do like your idea of ratchet style straps. Everyone's suggestions have been great and will now consider some type of additional 2x4 support on the sides with some style of side to side cross strap support.Richard S. wrote:As far as the forces go on the top every coal bin that I have ever seen break has always broken on the bottom, probably due to rotting more than anything. Having said that I would add some 2x4's to the top or near the top of that bin. You need at least one some support or it's going to bow out, the plywood itself is not enough even if you fill half way. Get a couple of eyehooks and cheap ratchet straps to go from one side to the other inside the bin, two or three will be more than enough. You can use cable too but the ratchet straps are really easy to remove.
Consider this, by the looks of it you can probably fit about 6 tons plus in that bin. that's 12,000 pounds or approximately 4 mid size cars. Most of the weight is transferred directly to the ground but you till have a large amount of force pushing out.
More to come. OH, thanks for the 6 ton figure.