Assume that traffic on a single-lane approach to a signalized intersection observes the Greenshield’s speed-density relationship. The jam density on the approach is 180 veh/mile and free flow speed is 60mph. Suppose the current signal is green and the traffic is moving at 40mph and passing through the intersection. After the green time ends, the signal turns red and vehicle queue starts to build up. The signal keeps red for 60 seconds and turns green again. Answer the following questions: 1. How fast does the vehicle queue build up after the signal turns red? 2. How far the vehicles are queued in upstream, i.e. the maximum queue length?

Assume that traffic on a single-lane approach to a signalized intersection observes the Greenshield’s speed-density relationship. The jam density on the approach is 180 veh/mile and free flow speed is 60mph. Suppose the current signal is green and the traffic is moving at 40mph and passing through the intersection. After the green time ends, the signal turns red and vehicle queue starts to build up. The signal keeps red for 60 seconds and turns green again. Answer the following questions: 1. How fast does the vehicle queue build up after the signal turns red? 2. How far the vehicles are queued in upstream, i.e. the maximum queue length?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter6: Fundamental Principles Of Traffic Flow

Section: Chapter Questions

Problem 15P

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