Making Concrete Flooring
Concrete floors begin with three basic ingredients: cement, water, and aggregates. Although many materials have been used as
cement in concrete's long history, today the most common cement material is Portland cement. This type of cement is made by
heating limestone together with clay, and grinding the resulting mixture with a sulfate like gypsum.
The next step in creating concrete is adding water and aggregates. The water binds the ingredients of concrete together,
as well as allowing the mixture to be poured into place. Aggregates make up most of the concrete. They can be either fine,
like sand and crushed stone, or coarse, like pebbles, quartzite, or crushed glass. Fine aggregates result in a smoother
concrete surface, while coarse aggregates are meant to be seen on the surface, adding texture and decoration.
Concrete Characteristics
Blended cements and chemical or mineral admixtures are sometimes added to the concrete mixture to give it additional
characteristics. Common admixtures include accelerators to speed up hardening or retarders to slow it down, plasticizers to
make fresh concrete easier to work with, pigments to add color, or bonding agents when new concrete is poured over old.
Mineral admixtures like fly ash or ground granulated blast furnace slag
may be added to replace part of the cement needed.
The cement, water, and admixtures are combined into a paste, and then thoroughly mixed in a high–speed,
shear–type mixer. The aggregates are blended with the paste and the rest of the water, and then finally mixed in a
conventional concrete mixer. Concrete is kept in motion in a mixer, where it will be transported to your home for pouring
from the mixer to your floor.
