Question

A pressure treated post will be placed in a sonotube. The post is 5.5" square and the tube is 10" in diameter, 48" long. The tube will then be filled with quickrete.

30 - 40lb bags equals 1 cubic yard
Formulas: V = pi^2h, V = L x W x H

How many bags will it take to fill the tube?​

Answer 1

So, it will take between 4 and 5 bags of quickrete to fill the tube.

Explanation:

To find the volume of the sonotube, you can use the formula for the volume of a cylinder: V = πr^2h, where r is the radius of the tube and h is the height.

First, you need to find the radius of the tube. The diameter of the tube is 10 inches, so you can divide that by 2 to get the radius: r = 10 inches / 2 = 5 inches.

Then, you can plug the radius and height into the formula to find the volume of the tube: V = πr^2h = π(5 inches)^2(48 inches) = about 235.61 inches^3.

To find the number of bags of quickrete you will need to fill the tube, you need to convert the volume of the tube to cubic feet and then divide by the number of cubic feet in a bag of quickrete.

First, you can convert the volume of the tube to cubic feet by dividing by 1728 (the number of cubic inches in a cubic foot): V = 235.61 inches^3 / 1728 inches^3/ft = about 0.14 cubic feet.

Then, you can divide this volume by the number of cubic feet in a bag of quickrete to find the number of bags you need: 0.14 cubic feet / (1 cubic foot / 30-40 bags) = about 4-5 bags.

So, it will take between 4 and 5 bags of quickrete to fill the tube.