At what weight would a pvc tube fail?

Here's a little mechanics of materials refresher for ya! I have a PVC tube about 20' long. The OD is about 6.6" and the ID is 6.1". We'll say the tensile strength of PVC is about 7000 psi. Assuming you completely filled up the inside of the tube with a material similar to concrete and have it hanging vertically, (how it hangs is of no importance) how much load would it take to cause this tube to fail?