Estimate the Amount of Concrete
The amount of concrete required to secure the pole for your PV array will vary depending on the size of the PV array, the soil type, the pole’s height, local wind loads, and the dimensions of the finished hole. Deep, narrow holes will require less concrete than wider, shallower ones. You can determine the amount of concrete required by calculating the volume of the hole. The volume will equal the surface area of the hole times the depth. For square holes, the equation is L x W x D (length x width x depth). For round holes, the equation is Ï€ x R2 x D (Pi x the radius squared x depth). Pi is a mathematical constant that always equals approximately 3.14. Finally, a cubic yard of concrete equals 27 cubic feet.
Let’s run through the math required to calculate the amount of concrete required for two different hole sizes. The two holes my friend with the backhoe dug at my place are 3 feet by 3 feet across, and 3 feet deep. Each hole required one cubic yard of concrete (3 x 3 x 3 = 27 cubic feet or 1 cubic yard). If the holes had been round, and were 2 feet in diameter (1 foot; 0.3 m radius) and 5 feet deep, they would have only required 15.7 cubic feet of concrete (Ï€ x 12 x 5 = 15.7). To convert this to cubic yards, simply divide by 27 (15.7 ÷ 27 = 0.59 cubic yards).
If your interested in this or other aspects of home solar energy or residential wind power or would like to read up on some of the latest information on sustainable living or Green construction, then follow the link at http://www.shiftingsolutionsllc.com . Also here, you’ll find the DIY kits to build your own solar panels to use on the pole your about to install.
Tomorrow – getting the concrete ( sorry the boring part is nearly over)