During the peak hour, an urban freeway segment has a traffic flow of 6,000 veh/h, with 4,000 vehicles with one occupant and 2,000 vehicles with two occupants. The freeway has five lanes, four of which are unrestricted opening to all vehicles regardless of vehicle occupancy and one lane that is restricted for use by vehicles with two occupants. Link performance functions for the length of this freeway segment are tu = 30+ 0.5vu for the unrestricted lanes and tr = 20+2vr for the restricted lane, where t’s are in minutes and v’s are in 1,000 vehicles. Solve for the distribution of traffic among the lanes using the SO principle and compare the savings in person hours relative to a UE solution, assuming that the compliance is perfect and that no single-occupant vehicles use the restricted lanes.

During the peak hour, an urban freeway segment has a traffic flow of 6,000 veh/h, with 4,000 vehicles with one occupant and 2,000 vehicles with two occupants. The freeway has five lanes, four of which are unrestricted opening to all vehicles regardless of vehicle occupancy and one lane that is restricted for use by vehicles with two occupants. Link performance functions for the length of this freeway segment are tu = 30+ 0.5vu for the unrestricted lanes and tr = 20+2vr for the restricted lane, where t’s are in minutes and v’s are in 1,000 vehicles. Solve for the distribution of traffic among the lanes using the SO principle and compare the savings in person hours relative to a UE solution, assuming that the compliance is perfect and that no single-occupant vehicles use the restricted lanes.

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter9: Capacity And Level Of Service For Highway Segments

Section: Chapter Questions

Problem 21P

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