Many products used every day can be recycled or are made from recycled materials, and concrete surfaces are no different! As the demand for eco-friendly practices while reducing project costs increases, Bauman Landscape & Construction discusses recycled concrete production and the many ways it impacts every life.
What Is Concrete Recycling?
At the core, it’s simply breaking, removing, and crushing an existing concrete surface into a specified quality and size. The process can be performed on site with a concrete recycling machine or portions of the surface taken to a plant off-site. Once crushed, embedded elements, such as reinforcing steel, are removed and separated, along with potential contaminants, such as asphalt, glass, roofing materials, and sealants. The final size of aggregate usually falls under one of two categories — coarse and base coarse.
These aggregates range in size from 3/8-inch to 1 1/2 inches and are frequently used as backfill, concrete aggregate, road base, and stone road and driveways.
Generally less than 1 ½ inches in diameter, this aggregate is used to create a dense layer with minimal voids. It’s commonly used in backfill and as a foundation for asphalt pavement, concrete pavement, and unpaved driveways and roadways.
What Are Recycled Aggregates Used For?
This type of paving is commonly used for hard outdoor surfaces, such as driveways and walkways, to reduce the amount of water runoff entering sewer systems. Because the water can filter through the pavement, it’s also helping to refill area groundwater supplies.
Larger pieces of crushed concrete may be destined for inclines, slopes, and other erosion-prone areas.
Because utility trenches frequently rely on gravel to help with water drainage, recycled concrete is a great substitute.
New Paving Base
Perhaps the most common use, many sub-base layers are created from recycled concrete due to the material’s durability and stability.
How Does Recycled Concrete Help Me?
Reduced Project Fees
Reusing aggregates lowers the number of new aggregates needed for concrete production. Then, transportation and waste removal fees are significantly reduced, thus lowering the overall project cost.
Carbon Dioxide Removal
Another benefit is the removal of carbon dioxide from the surrounding area. This is due to the aggregates, such as rocks, acting as carbon sinks — absorbing carbon dioxide from the atmosphere.
Using recycled concrete allows a concrete producer to earn LEED credits in two main ways. First, it’s considered post-consumer use when recycled aggregates are used rather than extracted aggregates, as outlined in Credit 4. Then, if at least 50 percent by mass of the waste redirects from a landfill, it generally qualifies for a Construction Waste Management credit.