Simulation-Based Environmental Risk Analysis of Mixed Traffic Flow at Intersections

Abstract

Environmental pollution risk caused by urban transport emissions is becoming increasingly serious and is an urgent issue in the process of establishing sustainable transport systems. In particular, the development of accurate microscopic models about motor vehicle emissions and the quantitative evaluation of the impact of various traffic management measures on traffic emissions are crucial. This study established and calibrated a simulation for exhaust emission analysis based on high-precision onboard emission test data. Using the simulation models, this study analyzed the emissions ratios of CO, HC, and NOx of mixed traffic (including light and heavy vehicles) at typical urban intersections. The results reveal the emission patterns of mixed traffic and show that heavy vehicles contribute to over 70% of CO, 65% of HC, and 90% of NOx at urban intersections even though the number of heavy vehicles is merely 20% of overall traffic. The results indicate that the storage length of lanes at an intersection does not have significant effects on traffic emissions. The results provide the scientific basis for formulating effective energy-saving, emission-reducing traffic management measures and establishing a green transport system.