Recycled crushed concrete trial at Auckland Airport

BPC and Auckland Airport conducted an innovative trial, reusing demolished runway concrete as a basecourse material for structural pavements. This initiative was the first use in New Zealand of recycled concrete for highly loaded structural airport pavements, setting a benchmark for sustainable infrastructure. It significantly reduced both carbon emissions and costs and showed a better way to build pavements sustainably.

In March 2025 a test section of taxiway was constructed using recycled crushed concrete (RCC) repurposed as cement treated basecourse (CTB). Rigorous field tests showed the recycled material met the Airport’s strict engineering specifications for load-bearing capacity and durability. The pilot section performed equivalently to standard materials, confirming RCC CTB as a viable alternative for heavy-duty airfield pavements.

The RCC-based solution reduced embodied carbon by around 75% compared to the traditional approach and delivered a cost saving of around 31% in pavement construction for the trial area.

Key to the trial’s success was the collaborative effort across multiple organisations. BPC, as head contractor, led the project, working with Urban Quarry (Winstone Aggregates), AECOM, Firth Industries, and Ross Reid Contractors as well as Auckland Airport. The trial marks a shift in how we can approach sustainable construction in our Auckland Airport projects, reducing reliance on new aggregate supply and turning a waste stream into a high-performance product on site.

The trial challenged and changed the stringent specification that traditionally prohibited recycled materials in the airfield pavement. The trial’s success has opened the door for formal specification updates – showing that recycled concrete can meet or even exceed performance of virgin quarried materials in high-load applications.