PROBLEMS 2. The 15 minute-traffic counts on cross roads 1 and 2 during peak hour are observed as 178 and 142 vehicles per lane respectively approaching the intersection in the direction of heavier traffic flow. If the amber times required are 3 and 2 seconds respectively for two lanes based on approach speeds, design the signal timings by trial cycle method. Assume an average time headway of 2.5 seconds during green phase.

PROBLEMS 2. The 15 minute-traffic counts on cross roads 1 and 2 during peak hour are observed as 178 and 142 vehicles per lane respectively approaching the intersection in the direction of heavier traffic flow. If the amber times required are 3 and 2 seconds respectively for two lanes based on approach speeds, design the signal timings by trial cycle method. Assume an average time headway of 2.5 seconds during green phase.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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An approach at a signalized intersection with a 60-second cycle gets 30 seconds of displayed green time. Yellow time is 4 seconds and all-red is 2 seconds (lost time is to be determined from standard assumptions). At the beginning of an effective red there are 4 vehicles in the queue and the saturation flow is 876 veh/h. The arrival rate is given by v(t) = 0.20 - 0.002t [with v(t) in veh/s and t in seconds after the beginning of the effective red]. What is the average vehicle delay for this approach in seconds at the end of the cycle (until the next effective red) that started with the 4 vehicles queued at the beginning of the effective red? (Assume D/D/1 queueing. Please provide you answer in decimal form without units)
Q4b. What are the relevance of the following considerations in traffic signal timing design? i. Incorporating all-red interval in the inter-green period ii. Conversion of all vehicle categories to passenger car units (PCU)
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An approach to a pre-timed signal has 40 sec of effective green in a 75-second cycle.The approach volume is 700 veh/h and the saturation flow rate is 1600 veh/h.Calculate the time to queue clearance after the start of the effective green, themaximum number of vehicles in the queue, the total vehicle delay per cycle andthe average delay per vehicle assuming D/D/1 queuing.
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