 |
| Properties of Concrete |
What Are The
Properties of Concrete?
Most people
commonly use the words cement and concrete interchangeably. It's important to
note that cement is only one component of three concrete properties and the
term "concrete" is a mixture of the three.
Concrete
properties consist of three basic components: water, aggregate (rocks and
sand), and portland cement. Cement, usually in powder form, acts as a binding
agent when mixed with water and aggregates.
This
combination or mixture, when poured, hardens into this durable material called
concrete that we are all familiar with.
The Three
Basic Components of Concrete
1. Portland Cement - The cement and water
form a paste that coats the aggregates and sand in the mix. The paste hardens
and binds the aggregates and sand together.
2. Water - Water is needed to form a chemical
reaction with the cement (hydration) to form heat. This starts the drying and
hardening process. Water is also used to provide workability with the concrete.
The amount
of water in the mix in pounds compared with the amount of cement is called the
water/cement ratio. The lower the w/c ratio the stronger the concrete.
3. Aggregates - Sand is the fine aggregate
and crushed stone and gravel are the coarse aggregate. These two materials help
strengthen the concrete.
Some Desired
Properties of Good Concrete
1. A workable mix that is easy to place and
consolidate.
2. A high quality concrete using the lowest
water-cement ratio possible, using the proper size coarse aggregate practical
for the job you're doing, using the optimum ratio of fine to coarse aggregate.
3. For hardened concrete resistance to
freezing and thawing, deicing chemicals, wear resistance, strength, and low
permeability (water tightness).
These are
the basics of concrete properties to produce a concrete mix. There are other
admixtures that are added to improve workability, durability, and set times.
