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Understanding Aggregates

Here at Flesherton Concrete Products, we want to help you get the right supplies for your construction project, and one type of supply used in countless applications is aggregates. In this article, we’ll provide a brief overview of what aggregates are, what their purpose is, and the different varieties in order to help you decide which is best for your project.

Types of Aggregates

In general, there are two main types of aggregates: coarse and fine. Coarse aggregate is made of crushed rock, gravel, or screenings, while fine aggregate is typically made of smaller particles like sand. Coarse aggregates are generally used when making structural concrete that will be used in buildings, railway track ballast, and similar heavy-duty structures. Fine aggregates, on the other hand, are more commonly used to make mortar, in plastering, to fill in the layers of road pavement, and the like.

What Makes a Good Aggregate?

The choice of aggregate material matters a great deal for the overall strength and integrity of the finished concrete. A good aggregate is strong and hard–meaning that crumbly stone such as sandstone is a poor choice–as well as durable, to stand up to wear and tear. The material also needs to be chemically inactive, so that the aggregate doesn’t react to the cement. In addition, the aggregate pieces should come in a range of sizes, so that the pieces fit together well and form a strong and dense structure. Finally, the aggregate needs to be clean, as dirt particles can prevent the cement from bonding to the stone.