Why We Use Cement in Concrete
The terms concrete and cement are often interchanged to mean the same thing—like concrete driveways. However, concrete and cement are not the same things. They are completely different materials and serve different purposes.
What Is Cement?
Cement is an ingredient used in making concrete. Cement is a mixture of clay and limestone. Both are heated to very high temperatures and then ground into a fine powder. The heating process is essential to activate the chemical binding action and hydration processes found in cement.
If you were simply to grind up hardened clay and limestone, you would not get the same results. While you would have a fine powder, it would not have the same results as you get by heating these materials to very high temperatures.
- Fun Fact: To activate the chemical properties of cement, clay and limestone must be heated to at least 2,642 degrees Fahrenheit.
What Is Concrete?
Concrete is a mixture of different materials that consists of mixing aggregates together with water. Aggregates can consist of using sand, gravel, ground brick powder, stones, pebbles, and cement. The aggregates used will determine how strong the concrete is and what it can be used for.
For instance, if you were to mix sand, gravel, and ground brick powder together, you would get a cement mixture that could be used to make paving tiles, but they would not be as strong as a concrete mixture that included cement. This is because cement has the special chemical binding and hydration processes ground brick powder does not.
What Else Is Cement Used for Besides Concrete?
You might be surprised to learn that cement is not just for mixing together with aggregates to make concrete. Cement can be mixed with other aggregates to make other materials too.
For instance, plaster powder, which is also called cement plaster, is made from a mixture of cement and sand. Water is then added to make plaster paste, which can be used for a variety of purposes.
Another example is mortar, commonly used in between bricks to secure them in place and hold them together. Mortar powder is made by combining lime, cement, and sand. When it is mixed with water, you get wet mortar you can spread to secure bricks together.
How Was Cement Invented?
Cement was an invention discovered by Joseph Aspdin, a bricklayer from the U.K. He had been experimenting with different materials to try to develop an “artificial” stone that was as strong as the Portland stone. Then, sometime in the 1820s, he heated clay and limestone together and then crushed it into a powder.
He used this powder and mixed it with various aggregates, essentially also discovering the modern mortar and plaster that we still use today. He also discovered that, with the right mixture of water, sand, gravel, and cement, he had a concrete material that would continue to strengthen as it hardened and aged.
The cement he invented came to be known as Portland cement. Some people assume this is a brand name or business name. However, it is just one type of cement that just so happens to be one of the most widely used, even today.
How Many Types of Cement Are There?
There are multiple types of cement and various cement categories used, depending on the manufacturer. Some of the different types of cement include:
- Portland Cement
- Pozzolana Portland Cement
- Quick Drying Cement
- Quick Hardening Cement
- White Cement
- Expansive Cement
- Colored Cement
What makes each cement mixture different is the type of materials used in its composition. Additionally, over the years, gypsum powder has become commonly used in cement. Gypsum helps regulate the hardening and curing time for cement by slowing it down.
This is ideal when large amounts of concrete are made for large construction projects. The gypsum helps to keep the concrete wet and workable for much longer. Without the gypsum, the chemical binding and hydration processes start immediately. With the gypsum, the chemical processes are slowed down.
Why Is Water Mixed into Cement?
Mixing water into cement is necessary to start the chemical binding and hydration processes. The cement powder dissolves, and the chemical reactions start, which releases silicon and calcium ions. These ions spread throughout the wet cement and form a film around other materials. As the cement dries, the chemical reactions continue.
Essentially, the film creates an added binding layer, which strengthens as it hardens. The process doesn’t stop right away, either. While at the surface level it might look like the cement has hardened in a matter of days, at the chemical level it is continuing to harden for months to years, depending on what materials the cement is mixed with, the ratio of cement, and other such factors.
Why Is Cement Important in Construction?
Cement is a vital component that is used to make concrete. Without it, concrete would not be as strong. Concrete driveways would not last as long as they do without cement.
Buildings would not be able to use concrete supports and columns with metal rebar if it wasn’t for cement. Instead, the entire support and column structures would need to be made from steel.
Mixing cement into concrete also helps make the material easier to work with and use. It can be spread, smoothed, and even shaped like concrete blocks. Thanks to the continued chemical binding and hydration processes in cement, the concrete continues to also strengthen with time.
What Are Some of the Advantages of Using Concrete?
When you are considering different types of construction materials to use for driveways, parking lots, and buildings, concrete offers many advantages, which can make it the perfect solution.
- Concrete can be poured and shaped. You can use it to make patio pavers, flowerpots, support columns, and so on, just by pouring it into a mold with the desired shape.
- Concrete can be stamped and imprinted with designs. You can stamp or imprint different images and text into wet concrete that will set and become permanent once the concrete cures.
- Concrete is an affordable material. The costs of concrete are much lower than other types of materials like steel or asphalt.
- Concrete is eco-friendly. Concrete is made from natural materials readily found all around us.
- Concrete is recyclable. Concrete can be recycled and reused an endless number of times.
- Concrete is water-resistant. Once the concrete sets and cures, it resists water. This makes it perfect for underwater applications like swimming pools, dams, waterways, bridges, etc.
- Concrete requires little to no maintenance. Once the concrete is set and cured, there is not much else to do. You will want to get the concrete sealed when it is used for outdoor applications like a residential concrete driveway. Other than hosing it off to keep it clean and resealing it periodically, not much else needs to be done.
- Concrete is resistant to high temperatures. One reason concrete is used in building construction is its ability to withstand high temperatures much better than steel or wood, which is an important fire safety consideration.
Hopefully, now you can see why cement is used in concrete and why it makes such a great choice for commercial and residential concrete driveways, parking lots, and building construction.
For all your concrete residential and commercial needs in the Great Houston Area, including concrete driveways, swimming pools, sidewalks, foundations, building construction, and more, please feel free to contact Cross Construction Services at 713-254-1703 today!
We are a full-service operation and offer custom design and build services, construction management services, patio room design, pergola construction, and more! No project is too big or too small.