Using reclaimed concrete in road construction

The project reclaimed 13,000 m3 of concrete and 5,000 m3 of asphalt for on-site reuse, saving R3.1 million in landfill airspace. While on-site crushing would have saved 36% compared to virgin materials, moving the crusher to Philippi increased costs by 20% over virgin sources due to haulage. Technical findings recommend SANS 3001 testing, a grading modulus of 2.2-2.3, and crushing to 37 mm for G5 material to improve workability and CBR values.

• The project successfully diverted 13,000 m3 of concrete and 5,000 m3 of asphalt from waste to reuse in the highway construction, resulting in a saved landfill airspace value of R3.1 million.
• The financial viability of using recycled materials is highly sensitive to haulage and crusher location; while on-site crushing would have yielded a 36% cost saving over virgin material, the use of an alternative site in Philippi made the recycled material 20% more expensive than virgin commercial sources.
• Technical recommendations for recovered aggregate include crushing to 37 mm for G5 material and achieving a grading modulus of 2.2-2.3 to improve CBR values from 28-30% up to 70-80% and reduce variability in testing.
• SANS 3001 is recommended as the preferred testing standard for reclaimed aggregate because it is more conservative than TMH1, which tends to provide better results.
• The project demonstrated that required material performance can be achieved even when asphalt is included in the mix, despite a general contractor preference against asphalt mixes due to a lack of cohesion between particles.

APA

Barnes, D. K. (2019). Using reclaimed concrete in road construction. GreenCape. https://greencape.co.za/wp-content/uploads/2022/10/N2-ReclaimedConcrete-CS-v4WEB-3.pdf

Chicago

Barnes, Dr. Kirsten. Using reclaimed concrete in road construction. GreenCape, 2019. https://greencape.co.za/wp-content/uploads/2022/10/N2-ReclaimedConcrete-CS-v4WEB-3.pdf.

Wikipedia

{{cite report |last1=Barnes |first1=Dr. Kirsten |title=Using reclaimed concrete in road construction |publisher=GreenCape |date=2019 |url=https://greencape.co.za/wp-content/uploads/2022/10/N2-ReclaimedConcrete-CS-v4WEB-3.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{barnes2019using, author = {Barnes, Dr. Kirsten}, title = {{Using reclaimed concrete in road construction}}, institution = {GreenCape}, year = {2019}, url = {https://greencape.co.za/wp-content/uploads/2022/10/N2-ReclaimedConcrete-CS-v4WEB-3.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }