1374496 - An activity-based approach to evaluate CAV impacts on the transportation system in Southern California

Connected and automated vehicle (CAV) technologies attracted extensive attention in the past decade. As CAV brings convenience to travel, people's travel behaviors and patterns might change significantly. Existing models, however, cannot comprehensively evaluate the impacts on transportation systems. This study adopted an activity-based approach to evaluate the comprehensive CAV impacts on the transportation system in Southern California. A stated-preference survey was conducted and captured people's behavior changes associated with CAV deployment. On the supply side, the improvement of road capacity brought by CAVs was also incorporated. The model prediction demonstrated that the total trip number increased by 9% with 54% of the population would like to use CAVs. Among all trip purposes, work trips contributed to 49% of total trip number growth and 75% of the increased car-like mode travel distance. The model also indicated that Vehicle-Miles-Traveled (VMT) and emissions would increase by around 10%, and CAVs could worsen travel equity across income groups. To reduce the negative impacts caused by CAVs, we proposed and evaluated a series of travel demand management policies, namely telework promotion, transit subsidize, various parking prices, and auto trade-in. The results indicated that all policies help to reduce the VMT and emission growth, while their performances in enhancing travel equity vary across metrics including accessibility, travel frequency, and travel distance.