Arrival Turning Flows
Average Daily Traffic
The pedestrian crosswalk factor Xwalk Fact (XF) is applied to both HCM and geometric capacities.
Pedestrian crossings can reduce roundabout entry capacity.
When circulating flows are large the yield line capacity is usually less than the traffic capacity of the crosswalk so it has no effect on the entry capacity. However, when circulating flows are low the yield line capacity is usually higher than the traffic capacity of the crosswalk so the yield line capacity is reduced.
In NCHRP report 672 "Roundabouts: An informational Guide" page 4-14 Exhibits 4-7 and 4-8 give the capacity factors for single lane and two lane entries respectively. The crosswalk factors (XF) depend on the circulating flows passing the entries and the pedestrian flows on the crosswalk.
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