Reduction in Entry Capacity of Roundabout under the Influence of Pedestrians in Mixed Traffic Conditions

Abstract

Models developed in Highway Capacity Manual (HCM) are not suitable to cater to the effects of mixed traffic conditions and hence, its use is unjustifiable. This research investigates such a challenging problem as the effect of undesignated pedestrian crossings on the entry capacity of roundabouts. For the present study, field survey data were collected using video cameras from three roundabouts such that the base section (roundabout without pedestrian influence) and non-base sections (with pedestrian influence), both scenarios, were captured. A modified HCM equation was developed to estimate entry capacity and further, the reduction in capacity with respect to pedestrian volume is determined. Lastly, a relationship was developed to check the effect of pedestrian crossflow on the entry capacity. The relation shows that capacity reduced to 1841 Passenger Car Unit (PCU/h) when the pedestrian flow increased to 288 pedestrians/hour.

Keywords

• roundabout
• pedestrian
• entry capacity
• critical gap
• follow-up time