Curing is the maintaining of a satisfactory moisture content and temperature in concrete during its early stages so that desired strength and durability may develop. It is important to start curing slabs on grade immediately after finishing because the large area of slab surface can lose moisture or change temperature very rapidly.
Sealing is done after the concrete is cured out and dry and will allow the sealer to penetrate the concrete and seal it from within, (about 30 days of air drying after the concrete is placed and finished). Resealing your concrete before winter will help protect it from deicers that drip off your car.
Both are an accelerator that helps speed up the set time of concrete.
Calcium – the most common type of accelerator. However the chemical in it to help speed up the process is corrosive to re-bar and will slowly eat away at any reinforcement that you might have in your forms.
Non-calcium chloride – more expensive and does not set-up as quickly, but will not damage your re-bar in your forms.
It measures the consistency of the concrete or the workability of that specific load. The lower the slump, the more “stiff” the concrete is. The higher the slump, the more it will “flow”.
An admixture that will increase the slump of your concrete without altering the water-cement ratio. After the initial batch, anytime you add water, you are increasing the water-cement ratio and thus lowering the strength of the concrete. Using mid-range is a way to chemically induce the slump w/o jeopardizing the integrity of the concrete.
Fly Ash is a powder that is a by-product of coal and can be used to help make concrete. It does not have the same “glue-like” quantities that cement does, so you cannot use it by itself to make concrete, but you can substitute some of the cement to blend in with Fly Ash to make a durable product.
Fly Ash is a very common product, but it will slow down the set-time in comparison to a straight cement mix.
Cement is the fine powder that is used to help make concrete. Cement is the “glue” that you mix with rock, sand, and water to make ready-mix concrete.