Project-level instantaneous emission modeling from mobile sources for freeway lane closure using SHRP2 Naturalistic Driving Study data and microscopic traffic simulation

Abstract

This dissertation is one of the first studies which used the Second Strategic Highway Research Program (SHRP2) Naturalistic Driving Study (NDS) data to perform modal emission modeling at the project-level. SHRP2 NDS was the largest naturalistic driving study to date conducted in the U.S. which included instrumented vehicles with over 3,000 drivers that were recruited from six states. There is great potential to apply this data in modeling emissions as it will capture differences in driver behavior, roadway geometry, traffic conditions and their impact on emissions. The dissertation had two primary objectives: (1) apply the SHRP2 NDS data to model instantaneous exhaust emissions from passenger vehicles at four-lane divided freeway segments with work zones, and (2) examine the accuracy of microscopic traffic simulation models to replicate real-world vehicle trajectories in order to estimate emissions at work zones. Research studies related to assessing the impact of lane closure on vehicular emissions are limited considering that collecting data from field observations is resource intensive and expensive. In addition, the application of microsimulation models instigates certain constraints because various driver behavior and lane changing parameters must calibrated to ensure that the output from traffic simulation models can represent accurate real-world driving activity. Therefore, the first study focused on utilizing the vehicle kinematics data collected as part of the SHRP2 NDS to model emissions from passenger cars for work zones employed on four-lane divided principal arterials. The emissions models in this study considered different work zone configurations and varying congestion levels. Furthermore, the second analysis examined the ability of Vissim microsimulation model to replicate field conditions. A generic guidance to calibrate the driver behavior parameters in Vissim for freeway lane closure was applied and findings were compared to field observations from the SHRP2 study. Three different construction scenarios were implemented, i.e. AM-peak hour, PM-peak hour and nighttime off-peak lane closure