Sustainable Asphalt from Demolition Waste and Natural Fibers

The Challenge

Road infrastructure faces dual pressures: increasing construction waste volumes requiring sustainable disposal, and rising temperatures demanding more heat-resistant pavement materials. Traditional asphalt production is energy-intensive and relies on virgin aggregates, while climate change accelerates pavement degradation in warming regions.

The Solution

The research developed and evaluated several asphalt formulations through multiphysics property measurements. The GrindoSonic MK7 enabled ultrasonic pulse velocity measurements to assess mixture density and integrity, correlating these properties with rutting resistance performance and thermal behavior. This non-destructive approach supported optimization of both fiber content and mixing temperature parameters to achieve target performance levels.

Results

The optimized formulation combining 1% Alfa natural fibers with 20% construction demolition waste at reduced mixing temperature (150°C) delivers superior rutting resistance and thermal performance. Alfa fibers enhance thermal resistance and spectral reflectance, resulting in materials more resistant to thermal stress during service. This approach transforms waste streams into climate-resilient road materials while reducing production energy and environmental impact.

Key takeaway: Combining 1% Alfa fiber with 20% demolition waste at 150 degC mixing temperature produced asphalt with superior rutting resistance and thermal performance compared to conventional hot mix.