RC,

The weight the pipe structure will support is equivalent to the weight of water displaced. So in your case, the 6 inch pipe structure will displace about 3.9 cu ft. Water weighs about 62 pounds per cu ft. So The PVC structure you describe will support about 240 pounds minus the weight of the pipe (PVC has a specific gravity greater than 1 so it will sink by itself). If you are using schedule 40 PVC, the pipe structure will weigh around 75 pounds. So I would say with a 120 pound load + 75 the weight of the pipe, or total load about 195, you will be fine and the pipe will still stick up a little above the surface.

Note: I threw in a fudge factor here. To be on the conservative side, I used the inside diameter of the pipe for the calculation. Technically, I should have used the outside diameter so the pipe structure will actually carry a little more than stated.

Hope that helps.

Bill D.

Last edited by Bill D.; 03/07/16 06:22 PM. Reason: Clarification

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