80lb bags of what. you need to know the density of material working with.
3 inches = 1/4 footVolume = (308 x 1/4) = 77 cubic feet.That's (77/2) = 38.5 bags
100 cubic foot bags.
How many square yards in a 20x18 feet 3 inches thick
An area 10 foot x 10 foot is 100 square feet. 100 cubic feet of sand would cover it with a one foot deep layer of sand. If the sand needs to be 6 inches deep, then 50 cubic feet are be needed, or 25 cubic feet if the sand is to be 3 inches thick.
Figure about 1/2 cubic foot per 60 lb bag. The basic formula is to use equal amounts of cement, sand, and gravel. There are 27 cubic yards per cubic foot. It depends upon how thick you are planning to pour the concrete. For one foot thick, you would need 9 cubic feet of concrete. For 6" thick, you would need 4 1/2 cubic feet. I'll give you the answers for 1 ft thick and for 6" thick. For 1 foot thick, you need 9 cubic feet at 1/2 cubic foot per 60 lb bag equals 18-60 lb bags. That's six 60 lb bags of concrete, plus six 60 lb bags of sand, plus 360 lbs of gravel. For 6 inches thick, divide each of these by 2 to give 3-60 lb bags of concrete, 3-60 lb bags of sand, plus 180 lbs of gravel.
226.875
A 9x9 foot slab 4 inches thick requires a minimum of 1 cubic yard. If you go to 6 inches thick you will need 1.5 cubic yards.
3 inches = 1/4 footVolume = (308 x 1/4) = 77 cubic feet.That's (77/2) = 38.5 bags
A 10-foot round slab at 4 inches requires 1 cubic yard.
100 cubic foot bags.
How many square yards in a 20x18 feet 3 inches thick
An area 10 foot x 10 foot is 100 square feet. 100 cubic feet of sand would cover it with a one foot deep layer of sand. If the sand needs to be 6 inches deep, then 50 cubic feet are be needed, or 25 cubic feet if the sand is to be 3 inches thick.
Figure about 1/2 cubic foot per 60 lb bag. The basic formula is to use equal amounts of cement, sand, and gravel. There are 27 cubic yards per cubic foot. It depends upon how thick you are planning to pour the concrete. For one foot thick, you would need 9 cubic feet of concrete. For 6" thick, you would need 4 1/2 cubic feet. I'll give you the answers for 1 ft thick and for 6" thick. For 1 foot thick, you need 9 cubic feet at 1/2 cubic foot per 60 lb bag equals 18-60 lb bags. That's six 60 lb bags of concrete, plus six 60 lb bags of sand, plus 360 lbs of gravel. For 6 inches thick, divide each of these by 2 to give 3-60 lb bags of concrete, 3-60 lb bags of sand, plus 180 lbs of gravel.
A board foot is 12 inches by 12 inches by 1 inch thick. A board 6 inches wide, 24 inches long and 1 inch thick is still 1 board foot. Any combination of the three measurements that add up to the first, 12x12x1 is considered 1 board foot.
110
Depends on how thick the slab is, but 4" thick (.33 or 1/3 of a foot thick) would be typical. So multiply 10 x 10 = 100 square feet of area times .33(thickness in feet) equals 33 cubic feet. A 90 lb. bag contains about .66(two thirds) of a cubic foot of concrete, so you would need about 1 1/2 bags per cubic foot or 50 bags for 10'x10'x4"
well 18 tons will do a pad 20X20 4 inches thick... which is almost 1/2 a ton per square foot at 4 inches thick. so 1 ton per 8 inches thick per square foot. so I would say around 42 tons of crusher for your pad.