The components of standard concrete are simple: gravel, sand, water, cement and certain additives. But the science surrounding concrete is complex.
And yes, it’s still possible to install concrete that will last a lifetime. The process begins by ordering correctly. Always keep in mind that the cement powder in the mixture is the glue that holds the sand and gravel together. If you have small amounts of glue, the concrete will be weak, concrete used in standard residential foundation footings can be lower strength than concrete used for outdoor patios, sidewalks and driveways. The average person might think the opposite is true.
Concrete is supposed to crack, as concrete hardens, it begins to shrink ever so slightly– 1/16th of an inch for every 10 feet of length that’s poured, installation of contraction or crack control joints are necessary to encourage the concrete to crack at these locations. For the joints to work correctly, they need to be a minimum depth. Always make sure these joints are cut to a quarter or more of the thickness of the slab.
Concrete is incredibly strong when you try to squeeze or compress it. But it has only about 10 percent of this strength if you try to stretch or bend it.m, small hairline cracks from offsetting or widening are prevented by installing reinforcing steel. Wire mesh and -inch-diameter steel bars are readily available and very inexpensive. This steel needs to be in the middle of the concrete or slightly above the middle of the slab to provide the necessary reinforcement.