Preliminary performance assessment of asphalt concrete with paint sludge from automotive industries

Application of paints by spraying, extensively used in the automotive industry, represents a significant source of solid waste. The generation of paint sludge, from 2.5 to 5 kg for each painted car, is becoming an important problem from a management and environmental point of view owing to its huge volumes and hazardous characteristics. In this research a laboratory investigation was carried out in order to evaluate the performance of asphalt concrete mixtures obtained by using binders modified with paint sludge (10% on the base bitumen) in comparison with traditional asphalt concrete mixtures. The comparison between the two materials was carried out by taking into account volumetric and mechanical characteristics. Outcomes of the tests demonstrated that the addition of paint sludge does not alter mixture performance significantly. In particular, paint sludge has no effect on volumetric properties, it increases stiffness modulus but does not change resistance to permanent deformation.