What Are Aggregates and How Are They Used in Concrete?

In today’s fast-paced world, it’s easy to accept things at face value and move on. We often don’t consider the components or processes that make up the features in our everyday lives. When we think about the buildings, bridges, or roads we frequent, we know that concrete plays a significant role in them, but we don’t necessarily ponder the complex mixture of ingredients that creates one of the world’s oldest and most used building materials.

Ready Mix Concrete is composed of water, cement, aggregates, and admixtures. While each ingredient is key to the overall quality of the product, aggregates account for 60% to 75% of the total volume of concrete. In this blog, we’ll explain what aggregates are, the types available, and how they are used in concrete to create the durable structures we rely on daily.

 

What Are Aggregates?

The Portland Cement Association defines aggregates as “inert granular materials such as sand, gravel, or crushed stone.” Sand and gravel are harvested from pits, rivers, or seabeds, and rocks are taken from quarries and processed to the desired sizes and shapes. Rock and stones are crushed or blasted at cement plants before being transported to the Ready Mix Concrete batch plant. Suitable aggregates must be clean, hard particles free of any chemicals or coatings that could cause deterioration.

According to the Texas Aggregates & Concrete Association (TACA), “Texas is one of the most productive aggregate states in the nation.” The state is responsible for using 299.8 million tons of aggregates. 

 

Types of Aggregates

Aggregates can be broken down into two categories: Fine aggregates and coarse aggregates. 

Fine Aggregates 

These are smaller particles, that can pass through a ⅜” sieve. Natural sand and crushed stone are the most common types of fine aggregates. These help fill the spaces between coarse aggregates, enhancing the mix’s workability and compactness.

Coarse Aggregates

You guessed it, coarse aggregates are the larger of the two and typically range from ⅜” to 1 ½” in diameter. Gravel and crushed stone typically make up your coarse aggregates. They provide the bulk of the concrete’s structural strength and play a critical role in its durability.

Functions of Aggregates in Concrete

Aggregates influence multiple components of Ready Mix Concrete making it an indispensable ingredient and customizable depending upon the type of project you are working on. The basic four functions of aggregates are as follows:

Volume

Aggregates serve as fillers, thus reducing the amount of cement paste required. This not only lowers costs but influences the amount of shrinkage and thermal expansion. 

Strength

Including aggregates enhances concrete’s compressive strength. Coarse aggregates, in particular, contribute to the material’s load-bearing capacity.

Workability 

Using properly graded aggregates can improve the workability of the concrete mix, making it easier to handle, place, and finish.

Durability

The appropriate aggregate mix can impact concrete’s durability, influencing its resistance to wear and tear, weathering, heat retention, and decreased permeability.

 

Ready For Ready Mix? Contact Us Today!

While aggregates may not be the next topic of conversation at dinner, you now know that they are the unsung heroes of the concrete world. Leave the details to us. We pride ourselves on sourcing the best aggregates and mixing them appropriately to provide a long-lasting product. 

Ready Mix Concrete is measured in volume, and as the leading Ready Mix Concrete supplier in Northern Texas, we have taken the guesswork out of it. Using our concrete calculator, you can determine how much concrete you need for your project

AMCorp is your trusted Ready Mix Concrete supplier east of Dallas, TX. Contact AMCorp today to discuss your project or request a quote.