It will fit in a five-gallon bucket. When combined with water, 45 cubic feet of concrete is produced. In other words, one 60-pound bag of ready-mixed concrete or an equal Portland Cement/rock and sand combination. The cement accounts for 3% of the material by weight, so 1½ pounds of cement produces about 4¼ cubic inches at 15 pounds per square inch overpressure.
Concrete is a mixture of coarse and fine grains of stone or brick mixed with water and cement to form a solid mass. The coarser the grain, the stronger the concrete. Concrete used for paving roads, sidewalks, and driveways should be at least 3 inches thick. Concrete used for building structures such as houses, bridges, and buildings must be at least 6 inches thick. Thinner concrete is less strong than thicker concrete.
The strength of concrete depends on how it is made. If you use plain old concrete from the store and no additional ingredients are added, then it is called "gray" or "weak" concrete. To make this type of concrete stronger, add steel fibers or gravel to increase the volume fraction of cement paste (the mix of water and cement). This makes the concrete more rigid and resistant to cracking. Additions also improve the color and texture of the final product.
Each 80-pound bag of ready-mix concrete requires approximately 6 pints of water, for a total weight of 86.25 pounds per bag. Five ready-mix bags yield 3 cubic feet of wet mix weighing roughly 431.25 pounds. This amounts to 8.625 pounds of dry mix per cubic foot.
The amount of concrete that can be mixed with a single batch of cement is called its "batch size." The standard batch size for ordinary concrete is 500 pounds (227 kg). For high-strength concrete, which is more resistant to compression and other forces, a batch size of 1 ton (907 lb) or more is common. A large concrete mixer can mix larger batches than a small one; however, there is no fixed ratio between batch sizes and mixing capacity.
As a rough rule of thumb, if your mixer has a maximum load of 100 pounds, then it can mix about 10 yards (9 m) of concrete before you need to add more cement. If your mixer has a maximum load of 200 pounds, then it can mix 20 yards (18 m). Mixers designed to mix smaller batches may not be able to mix as much concrete as larger ones, so please refer to the manufacturer's instructions for exact quantities.
Concrete mixes usually include air entrained foam (AEF), which improves workability and reduces drying time.
For most concrete combinations, a decent rule of thumb is 150 pounds per cubic foot. You've moved approximately 100 pounds of concrete if you fill a 5-gallon pail. In a regular contractor-size wheelbarrow, you may be moving more than 800 pounds. That's a lot of weight to move without help from another person!
Cement weighs about 95% ground limestone and 5% clay, with some other ingredients including sulfuric acid to make it work as a setting agent. It is very heavy for its size, but it does pour like water until it hardens. Cement can be cut with a knife and will not bleed green if you try to paint it.
When cement is mixed with water and sand or gravel, the resulting mixture becomes plastic enough to be maneuvered but not so fluid that it flows out of your hands. The consistency of fresh concrete should be slightly thicker than pancake batter.
The specific weight of cement varies depending on how it is manufactured but is generally in the range of 950 to 1000 kg/m3. This makes it significantly heavier than water which weighs around 1 kilogram per liter. Cement is used in large quantities throughout the world and accounts for a significant proportion of our planet's carbon dioxide emissions.