Effects of hazardous spills by road accidents on pavement texture and its deterioration mechanism

Hazardous spills from road accidents affect road safety, reduce the skid resistance of pavement and have a long-term impact on pavement texture. This paper conducted experimental investigation and molecular dynamics simulations on common road accident hazardous spills (petrol, diesel, engine oil, and brake fluid). A low-cost close-range photogrammetry technique was used to measure changes in pavement texture. The texture wear process of the contaminated pavement was simulated by using the Hamburg Wheel Tracking Device. Material Studio was used to simulate the interaction between hazardous spills and the bituminous conglomerate. Results showed an average reduction of 47 % in terms of skid resistance after contamination, with an absolute maximum decrease of 71 % observed with engine oil spillage. While cleaning can partially restore skid resistance, effects of contamination vary by spill type. Petrol and diesel dissolve bitumen, weakening the pavement structure, whereas engine oil remains on the surface, posing prolonged safety risks. Brake fluid infiltrates aggregates, potentially affecting their mechanical properties. The correlation between texture parameters and skid resistance is weak on newly paved roads but become more pronounced as wear progresses. Simulations reveal that hazardous spills adhere readily to bitumen and aggregates, exacerbating contamination effects. These findings provide scientific insights for optimizing spill response strategies and improving road safety management.