Cement vs. Concrete: What Are the Differences?

Are concrete and cement the same thing? That’s a question concrete contractors are asked nearly every day because the words are often used interchangeably. While the two materials are related, in reality they are quite different and used for very different purposes.

Find concrete contractors near me

So what are the basic differences between cement and concrete? And what are the applications for each material? To give you a better understanding of which material is right for your next project, here are answers to these and other common questions about concrete versus cement.

What is cement?

Cement is a fine gray powder that’s mixed with water and other substances to make concrete and mortar. Cement is important because it’s the glue that binds the concrete mix together, giving it strength.

The most common cement type for general concrete construction work is ordinary portland cement (also called Type 1 cement). Made from finely ground limestone, shale, iron ore, clay, and other minerals, portland cement is hydraulic, which means it will chemically react with water to create a material with excellent binding properties. Although cement is a great adhesive, it is not suitable for use as a construction material on its own.

Learn more: What Is Cement?

What is concrete?

Concrete is made up of three basic components: water, aggregates (such as sand, gravel, and crushed stone), and Portland cement. In addition to these three main ingredients, concrete may also contain admixtures to modify setting times and enhance strength and workability. This combination of materials is much stronger and more durable than cement alone. Once the concrete mixture sets, hardens, and cures, it will continue to gain strength over time.

Learn more about the basic components of a concrete mix.

How are the materials related?

Cement is a key component in every concrete mix. When activated by water, it becomes the binding agent that grabs onto the aggregate particles and holds them together until the concrete sets.

How are the materials different?

Like flour in a cake, cement is just one ingredient used in the recipe for concrete, whereas concrete is the finished product, created by mixing cement, water, sand, and coarse aggregate. As a result of the chemical reaction that occurs when these components are combined, concrete attains enough compressive strength to withstand structural loads over a long lifespan.

What is cement used for?

Cement is rarely used on its own as a building material. However, its adhesive and binding properties make it an indispensable addition to concrete, mortar, cement-based overlays, and concrete patching materials.

What is concrete used for?

Concrete is one of the most widely used construction materials in the world, for both residential and commercial applications. Because concrete is strong and can be poured into forms or molds to assume almost any shape, you can use it to build everything from roads and buildings to stamped concrete driveways, patios, and sidewalks. Concrete has many indoor applications as well, including decorative flooring, countertops, sinks, and bathtubs.

Why do people say cement instead of concrete?

A common misconception is that concrete is merely wet cement, so many people will mistakenly say “cement” when they are really talking about concrete, such as a “cement sidewalk” or “cement driveway.” It is more accurate to say that a sidewalk or driveway contains cement but is made of concrete.

How much cement is in concrete?

The amount of cement used in concrete depends on the desired water to cement ratio, which compares how much water versus cement is used in a concrete mix. A typical concrete mix contains 10% to 15% cement by volume. Generally, the higher the percentage of cement, the higher the concrete strength.

Does more cement make concrete stronger?

While it’s true that more cement helps improve concrete strength, you don’t want to overdo it. Too much cement in a mix can make the concrete harder to work with and lead to poor bonding between the cement and aggregates. Finding the optimal balance between the components in a concrete mix is crucial for achieving the desired strength, durability, and performance.

Is it possible to make concrete without cement?

You can’t eliminate all the cement in concrete, but it is possible to replace up to 40% of the cement in a mix with fly ash, a byproduct of coal combustion that’s sometimes used as a mineral admixture in concrete. Like cement, fly ash acts as a binding agent when mixed with water. It also offers the advantages of increasing concrete strength, reducing permeability, and making the concrete easier to place and finish.

RELATED:
21 FAQs About Concrete
History of Concrete