Construction aggregates, more commonly referred to as “aggregate,” is the class of particulate material used in a broad spectrum of construction sectors. Traditionally made from sand, gravel, slag, and crushed stone, aggregate has received some criticism for its lack of sustainable production practices. Fortunately, recycled and geosynthetic materials are on the rise and quickly becoming the materials of choice for construction aggregate needs.
In this article, we’ll discuss how environmental sustainability and construction aggregates are beginning to cross over, and why this is a great thing for professionals and the planet alike.
An Introduction to Aggregates & Sustainability
Aggregate has been around since the time of the ancient Romans, serving as a vital mineral resource for major construction projects. These include structures for which the ancients are now renowned, like aqueducts, arches, and interconnected road systems.
The precedent quite literally paved the way for modern production and demand of quarries. So long as the quarries contain one or more varieties of a mineral that may be used for aggregate — such as gravel, steel slag, concrete, or even softer stones like pumice — these resource sites can be found around the world.
Although certain materials like sand are pretty universally easy to find, there are many areas of the world where quality granites, limestones, bedrock, and marble are quite difficult to access. For this reason, it is often necessary to import and/or transport aggregate to construction sites. This process is extremely energy intensive and pollutive, so construction materials manufacturers are looking into better methods of production that can minimize costs and conserve resources.
Recycled Aggregates
The primary source of recycled materials for construction aggregates is slag produced with the aid of blast furnaces and steel furnaces. Through a complex industrial process referred to as Pozzolanic Activity, the slag metals are incorporated with lime to develop strong hydraulic properties which allows them to be repurposed as a concrete or cement alternative.
Glass may also be used for recycled aggregates. Commonly, glass aggregates are used to replace pea gravel or varieties of crushed rock, but the material — which is not sharp to the touch! — is also a great alternative for pipe bedding in sewer and plumbing systems.
Geosynthetic Aggregates
When you recycle a plastic bottle, if it’s polymer-based, there’s a chance it might end up being used to make a construction aggregate. Polystyrene (commonly formed into styrofoam or thin, solid plastic) normally ends up in landfills because it is considered impractical to repurpose for its original use. Fortunately, polystyrene can be transformed instead of a geosynthetic aggregate. Although it might not be used to make another soda bottle or TupperWare dish, the new construction aggregate derived from plastic will produce a new, porous, hydraulically conductive material that can prevent clogs and can facilitate drainage applications.
Conclusion In an industry like construction, waste is one of the biggest contributors to pollution and landfill saturation. Fortunately, recycled and geosynthetic aggregates are becoming more and more common, creating sustainable alternatives that still get the job done, and do it well. For more information on sustainability, reusing materials, and recycling and repurposing heavy equipment, please get in touch with Wagner Used Equipment today!