VSP‐based emission factor calibration and signal timing optimisation for arterial streets

Abstract

Vehicle delay and traffic emissions have serious influences on traffic flow operations on an arterial street. The emission factors during green and red are calibrated based on vehicle-specific power (VSP), then three optimisation models are formulated by minimising vehicle delay or traffic emissions and by considering left-turn bays and coordinated signals. The field data from Dalian city of China are used to validate these models. Vehicle compositions include car, medium-size vehicle (MSV) and bus. Carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NO x ) emissions are estimated. Three coordinated signal control scenarios are proposed and four simulation experiments are carried out. The results indicate that the emission factor during green is greater than that during red for CO, HC or NO x produced by car, MSV or bus in each lane group on an arterial street; the emissions estimated by the motor vehicle emission simulator model are greater than those calculated by the VSP-based model; and the signal control scenario obtained by minimising total emissions performs better than that obtained by minimising total delay or both of them.