Evaluation on the highway asphalt pavement runoff with the gray correlation model

Road runoff is a major source of environmental pollution, significantly threatening nearby aquatic habitats. The structure of highway pavement is an important factor affecting the pollution of road runoff. In order to investigate the characteristics of the runoff pollution of asphalt pavement, water samples of the road runoff from the Shanghai-Chengdu expressway were collected and analyzed. The results show that the road runoff is of strong pollution with high concentration of heavy metals such as Zn, Pb, Cd, Cr, Ni. Evaluated by the Gray correlation model, the pollution of most water samples had exceeded the level IV of the national standard of surface water quality of China. Only one sample reached the level V of the standard .The results would provide the basis for the control of runoff pollution.