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Round columns, piers and deck posts. Enter the tube size, height and how many, and get yards or bags.
ConCal takes the slab, footings, steel and labor from one drawing and turns them into a bid your customer can sign.
A tube is a cylinder. Find the area of the circle, multiply by the height, and you have cubic feet.
Cubic feet = 3.1416 × (diameter in inches ÷ 24)² × height (ft)
Dividing the diameter by 24 turns it into the radius in feet in one step. Divide the cubic feet by 27 for yards, or by 0.6 for 80 lb bags.
Worked example. Eight 12 inch tubes, 4 feet deep. One tube is 3.1416 × 0.5 × 0.5 × 4 = 3.14 cubic feet, about 6 bags. Eight of them are 25.1 cubic feet, or 0.93 yards before waste.
| Tube | Cubic feet per foot | 80 lb bags per foot |
|---|---|---|
| 8 in | 0.35 | 0.6 |
| 10 in | 0.55 | 0.9 |
| 12 in | 0.79 | 1.3 |
| 16 in | 1.40 | 2.3 |
| 18 in | 1.77 | 2.9 |
| 24 in | 3.14 | 5.2 |
If the tube sits on a bell or a spread footing at the bottom, figure that part on its own with the footing calculator and add it in.