Aggregates, paramount to the development of the world economy, are construction materials consisting of crushed stone, sand and gravel. Construction aggregates are core to Summit Materials business strategy as they are key material components used in the production of asphalt, concrete, and cement, and are used for highway, commercial and residential construction.
Aggregates are generally extracted from the earth using surface or underground mining methods and are produced from natural deposits of various materials such as limestone, sand and gravel, granite and trap rock.
When mixed with a “binder” or “glue”, aggregates are used as a core structural component used to create other materials. With the addition of Portland cement and water, ready- mixed concrete can be produced for use in structures, pavements, bridges, etc... With the addition of liquid asphalt cement, (liquid AC), hot mix asphalt is produced for use in roadways, airport runways and parking lots.
While most of the population may not be familiar with the term “aggregates”, our lives are continuously impacted by them. Whether it is a material used in the construction of housing, hospitals, schools or work space, or as a product used in the construction of roads, bridges and parking lots, we constantly touch aggregates to allow us to perform the functions of our daily lives.
On average, 10 tons of aggregate are required annually for each U.S. citizen, or approximately 3.0 billion tons annually. It requires approximately 38,000 tons to construct a one mile stretch of a typical four-lane interstate highway.