Impacts of Cycle Length and Volume on Traffic Emissions and Delay at Signalized Intersections

Abstract:

Considering different arrival types which can represent the quality of the progression, this study developed an emission estimation algorithm at signalized intersections by reconstructing the vehicle trajectory based on shock wave theory and applying Vehicle Specific Power Model. Then, the delay model proposed in HCM 2010 was combined to analyze the impacts of signal cycle length and traffic demand on emissions and delay, what’s more, the game relationship between emissions and delay was discussed. Results indicate that both emissions and delay per vehicle become smaller when signalized intersections experiencing a more favorable progression under equal condition. As cycle length increases, the pervehicle emissions decrease while the delay decreases and then increases, specifically, the higher quality of the progression, the larger the optimal cycle corresponding to the minimum delay. The impact of traffic flow on pervehicle emissions was found to be insignificant，however, control delay is much more sensitive to traffic demand than emissions.

Key words:signalized intersections; arrival type; traffic emission; delay