Developing Highway Capacity Manual Capacity Adjustment Factors for Connected and Automated Traffic on Roundabouts

Connected and automated vehicles (CAVs) are expected to transform future transportation systems. Over time, these might enhance traffic efficiency safety, especially at urban intersections. Therefore, it is essential make adaptations the analysis models that currently designed for human-driven only. This paper aims assess impact of CAVs on entry capacity roundabouts develop an approach adjust values calculated by Highway Capacity Manual (HCM) planning level analysis. Both single- double-lane studied under various CAV market penetration rates conflict flow in this paper. A specific application, cooperative adaptive cruise control (CACC), evaluated study because enhances car-following behavior roundabout entrance has best potential improving capacity. The simulation results indicate introduction can substantially improve as rate increases both roundabouts. improvement more significant single-lane than roundabout. capacities different compared with estimated from base HCM acquire adjustment factors. Finally, a table factors provided implementation models.