What is Recycled Concrete and How Can It Be Used?

Recycled crushed concrete is an environmentally and economically friendly aggregate alternative that removes the need for quarried materials. Recycled concrete is used in a few major applications in the construction industry – especially in Houston, where natural stone cannot be sourced and must be brought in by ship, rail or truck.

In general, recycled concrete is crushed into smaller pieces of aggregate before it is used in various projects. As such, it is not appropriate as the surface course for pavement, but it can support that new pavement with improved load-bearing capacity and stabilization.

What are the Applications of Recycled Concrete in Houston?

In Houston, recycled concrete serves as a replacement aggregate. In this way, crushed recycled concrete is used like limestone (another aggregate) in construction projects.

Recycled concrete is useful in the following applications:

  • Road base – Crushed recycled concrete is an effective subbase or base material for roads, sidewalks and other pavement projects. Concrete’s high compressive strength makes it a perfect load bearing material in these applications. Crushed concrete also facilitates efficient drainage, which is a very important consideration in Houston’s wet climate.

  • Stabilization for parking areas – Crushed concrete’s load bearing capacity and composition also makes it an effective tool for stabilizing parking areas. When soil shifts and subsides beneath parking lots, it causes the large fractures and depressions that Houston drivers are familiar with. Crushed concrete can be used to effectively infill any areas where the base has failed, restoring the parking lot’s structural integrity.

  • Erosion control – Crushed recycled concrete can also slow the rate of soil erosion due to wind or rain. When used in this application, crushed concrete is referred to as bull rock. You will find it in landscaped areas, in retaining walls, in parks and on sloped areas where erosion is a concern – like retention or detention pond banks.

  • Construction site access – Recycled concrete is a frontline choice for construction site access, as it provides a good transition from urban roads to rugged project site conditions. It is also quick to lay down, inexpensive, and can be easily removed once the project is complete.

Recycled crushed concrete is viable in an array of road, pavement and infrastructure projects – but what makes it a frontline choice for these applications? It comes down to economic and environmental factors.

What are the Benefits of Recycled Concrete in Houston?

Recycled crushed concrete is particularly valuable to Houston construction companies, where it serves as a replacement aggregate in various construction projects. Here are some of the reasons Houston crews rely on the recycled material:

  • Recycled concrete is far easier to source – If there is a concrete recycling plant in the area, contractors have a nearby aggregate supplier to work with. Contractors can meet plant personnel and ensure their aggregate needs are addressed. There is far less distance to cover as well, which provides obvious cost benefits, but also reduces the likelihood that something will go wrong during transport. For process-oriented contractors who must stay on schedule, sourcing local aggregate makes sense.

  • Recycled concrete is less expensive than virgin materials and aggregates – Recycled concrete is comparable in cost to virgin materials, but there are additional factors that bring its cost down further. For one, transport costs are lower in Houston due to the reduced shipping distance. Two, recycled concrete is about 10-15 percent lighter than virgin concrete, so contractors get more recycled concrete by volume. Contractors get more for their money in other words, reducing the project’s cost. There are also no landfill fees to worry about with recycled concrete.

  • Recycled concrete has a lower environmental footprint – For most contractors, cost realities are what drive project decisions, but with an increasing focus on sustainability, it is likely that recycled concrete will take a greater role in construction going forward.

    Recycled concrete saves millions of tons of waste from local landfills, reduces pollution, reduces the consumption of new materials and makes for a sustainable approach to infrastructure, road and pavement projects. In some cases, recycled concrete can be produced from demolition materials harvested from the project site.

When recycled crushed concrete is available, it offers considerable cost and logistical advantages. These advantages are pronounced in Houston, as the closest sources of natural stone are hundreds of miles away. For example, it is common for Houston contractors to source their stone aggregates from San Antonio or even Mexico. Recycled concrete eliminates the need to move materials that far.

Where is Recycled Concrete Sourced From?

Recycled concrete is taken from the remains of other construction and demolition projects. When old buildings and pavement are torn down demolished, the remaining concrete is typically transported to a landfill. According to the EPA, about 150 million tons of this waste pavement – concrete and asphalt – was dumped in U.S. landfills in 2018.

When concrete is recycled, it is redirected from this waste stream and taken to recycling facilities. Here, the construction and demolition remains are broken down into smaller pieces of concrete using heavy machinery. Once the material is reduced to a manageable size, the small chunks are fed into a series of impact hammers that reduce their size further. A series of conveyor belts transport this material through sorting equipment that removes unwanted materials like scrap metal. The sorted concrete aggregate is then readied for shipment so it can supply local construction or infrastructure projects.

Recycled Concrete is an Environmentally and Budget-Friendly Aggregate Alternative

Recycled concrete offers the same, or better, performance than other types of aggregate, only it is less expensive, easier to get in some areas, and offers better sustainability. If your construction project also includes demolition, you may have the resources onsite already.

If so, contact an expert pavement contractor to see how recycled concrete can be used with your project to reduce its cost and environmental impact.