After a roadway has reaches a level of disrepair, the only option is to replace the surface. Asphalt surfaces consist of simple input materials. Because of this, an older surface can be reusable as recycled asphalt. This material is usable in new paving projects and construction materials.
Asphalt Bitumen
Asphalt bitumen is a tar like substance that is viscous when heated and hard when cooled. Bitumen is usable in asphalt paving for its ability to bind together and its reusability. When asphalt heats to around 300 degrees, the bitumen will melt allowing it to pave a surface. Bitumen makes for a great sustainable option for paving surfaces. This due to the qualities bitumen has.
How is Asphalt Recycled?
Asphalt is first removed from a paved surface by either tearing it up or grinding the surface down. Any remaining debris is crushed up to ensure that the mix will be even when heated. Heating the asphalt debris up will melt the bitumen allowing the mixture to be reusable. When the recycled asphalt heats to a certain level, it can apply to new paving materials. This will ensure the quality is as high as its regular counterpart.
Asphalt Inspection
The asphalt recycling process begins with an assessment of the surface. Factors like the asphalt’s density and mix define how the material is recyclable. Since not all asphalt surfaces have the same composition, it is crucial to take note of the asphalt’s mix. Doing so allows it to be integrable and reusable to match all paving regulations.
Asphalt Milling
After inspection, the asphalt is usually milled or torn away. This is because the lower layers of an asphalt surface are usually still usable and strong. An asphalt surface tops loose material and various layers. These are layers that help with drainage and leveling. Only the top layers of the asphalt paving can usable for recycled asphalt designs. This is due to the top layers containing the asphalt bitumen.
Recycled Asphalt Storage
Recycled asphalt goes to a processing plant for long term storage and processing. The material is usually expensive to send to a landfill. But because it still has value it’s sellable to asphalt plants. The recycled asphalt will sit at a processing plant until a project or mix design may need it. Asphalt plants will begin processing the material by grinding it into smaller pieces. This will allow it to be ready to heat and use.
Asphalt Heating
Sometimes there will be a project that needs recycled asphalt. During these times, the plant will send the material through an asphalt recycler. The recycler will heat up the asphalt and mix it to ensure that the bitumen is viscous and uniform. The material’s mix, at its heating and mixing stage, can consist of extra material and bitumen.
Recycled Asphalt Regulation
Depending on the local zoning and paving regulations recycled asphalt may have limited uses. For the balanced RAP/RAS Mix design in Austin, Texas the maximum amount of recycled asphalt used for city paving projects must be 20% at the surface, 30% at the intermediate level, and 40% at the base.
Local laws and regulation may require you to add the recycled asphalt to a mixture of new materials. Paving projects for private land and business has fewer requirements. As a result, you can use mix designs that have higher amounts of the material in them.
Recycled Asphalt Shingles
For asphalt that does not make it into new paving projects, there are still many other uses for it. One of the many industries using old asphalt materials is roofing manufacturers. Roof shingles are made out of the asphalt bitumen, tar, and aggregate that is collected from old paving projects.
Sustainable Paving
Recycling asphalt paving projects allow paving plants to use less new input materials. The paving industry is highly reliant on recycled asphalt because they are able to keep costs low and conserve the environment. When an asphalt roadway is replaced the old roadway also does not need to be sent to a landfill.
Recycled Asphalt Paving Company
Lone Star Paving has it’s own plant located in Austin, Texas that processes recycled asphalt. We are able to take in materials from projects around the Austin area and reuse them for you. For more information about recycled asphalt paving contact Lone Star Paving today.
