Life and Times of a Cubic Yard of Concrete
you know me? Yes, you might THINK you know me, but do you REALLY know
me? Sure, you can walk on me, ride your bike on me, walk your dog on
me (what a mess), you even park your car on me (ouch!) But what am I?
Am I just a gray, hard flat surface to use and abuse? Perhaps I need
to introduce myself in more detail.
things are involved in my creation. A material called "cement" must be
manufactured first. Cement and concrete are not the same thing. Cement
is just one ingredient in concrete, that holds the other ingredients
together. Cement itself is made from several things, primarily
limestone. When the limestone is ground up into very fine powder and
combined with gypsum and some other materials, it becomes a material
that actually "glues" the concrete together. Without cement, concrete
would just be a muddy mess.
most abundant ingredients of concrete are aggregates,
which are basically sand and stone. Aggregates make up about 70% of
concrete's volume. The larger pieces of aggregate are called "coarse
aggregate". Some examples of coarse aggregate are gravel, limestone, and
slag. If it looks like a rock, it's coarse aggregate. The "fine
aggregate" is usually sand, just like the brown sand used in sand boxes.
blend the cement, sand and stone, we need to mix them in a concrete
mixer. Some concrete plants have large mixers in their batch plants, but
most concrete is mixed in concrete mixer trucks. In order to make the
mixture into concrete, you must add water. Clean water must be used - if
you can't drink it, don't use it for cement. When the water is added to
the blended materiel, it reacts with the cement. This reaction is called hydration. Hydration
is what causes the concrete to eventually harden, or "set up".
the aggregate makes up about 70% of a cubic yard of concrete, the Cement
only makes up about 10% of the volume. The water needed to properly mix
the concrete and hydrate the cement is about 15% of the volume. The
remainder of the composition is actually air. Very small, microscopic
air bubbles are created by adding a chemical to the mix. These bubbles
help the concrete to be more durable when exposed to freezing
that all the ingredients are mixed together, I have become Concrete.
They deliver me to the customer in a concrete mixer truck, and pour me
into forms, or molds. Then they smooth me out until I'm level, and
finish the surface to the desired finish. All of this work MUST be done
fairly quickly, as the concrete starts to set up (harden) within a
couple of hours, even faster in hot weather. Once the concrete sets up,
it's very important to keep moisture in the concrete. The moisture will
continue to react with the cement, which continues to make the concrete
harder and more durable.
areas where cold, freezing weather is present, the concrete will
probably have salt or other de-icing agents applied to it. Whether it is
purposely placed on the concrete, or just drips off of parked cars, salt
can do a great deal of damage to my surface. To help protect me from
these damaging chemicals, you need to regularly seal my surface with a
high quality concrete sealer. It works on concrete almost like waxing
your car protects its finish. Take care of me, seal my surface
regularly, keep those nasty de-icers off of me, and I'll be there for
you for many years to come.
2015 Riverside Builders Supply Inc.
Back to Top