A pretimed four-phase signal has critical lane group flow rates for the first three phases of 200, 187, and 210 veh/h (saturation flow rates are 1800 veh/h/ln for all phases). The lost time is known to be 4 seconds for each phase. Assuming Xi = 0.9. If the cycle length is 60 seconds, what is the estimated effective green time of the fourth phase?

A pretimed four-phase signal has critical lane group flow rates for the first three phases of 200, 187, and 210 veh/h (saturation flow rates are 1800 veh/h/ln for all phases). The lost time is known to be 4 seconds for each phase. Assuming Xi = 0.9. If the cycle length is 60 seconds, what is the estimated effective green time of the fourth phase?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter8: Intersection Control

Section: Chapter Questions

Problem 26P

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A pretimed four-phase signal has critical lane group flow rates for the first three phases of 200, 187, and 210 veh/h (saturation flow rates are 1800 veh/h/In for all phases). The lost time is known to be 4 seconds for each phase. Assuming X₁ = 0.9. If the cycle length is 60 seconds, what is the estimated effective green time of the fourth phase? 6.93 sec O 21.89 sec Ⓒ 7.78 sec Q 7.41 sec
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An intersection has a three-phase signal with the movements allowed in each phase and corresponding analysis and saturation flow rates shown in the table below. Assume the lost time is 4 seconds per phase and a critical intersection v/c of 0.90 is desired. O 15.552 sec O 11.462 sec O 14.825 sec Phase O 16.065 sec Allowed movements Analysis flow rate Saturation flow rate Using v/c equalization ratio, calculate the effective green time for phase 3 1 NB L, SB L 330, 365 veh/h 1700, 1750 veh/h 2 NB T/R, SB T/R 1125, 1075 veh/h 3400, 3300 veh/h EB L, WB L 110, 80 veh/h 650, 600 veh/h 3 EB T/R, WB T/R 250, 285 veh/h 1750, 1800 veh/h
An intersection has a three-phase signal with the movement allowed in each phase and corresponding analysis and saturation flow rates shown in the table below. Assume the lost time is 4 seconds per phase and a critical intersection v/c of 0.90 is desired Phase 1 2 3 Allowed Movement NB L, SB L NB T/R, SB T/R EB L, WB L EB /T/R, WB T/R Analysis Flow Rate 330, 365 veh/h 1125, 1075 veh/h 110, 80 veh/h 250, 285 veh/h Saturation Flow Rate 1700, 1750 veh/h 3400, 300 veh/h 650, 600 veh/h 1750, 1800 veh/h Calculate the Following: 1.)Sum of flow ratios for critical lane groups 2.)minimum cycle length 3.)using v/c equation ratio, calculate the effective green time for phase 1 4.)using v/c equation ratio, calculate the effective green time for phase 2 5.)using v/c equation ratio, calculate the effective green time for phase 3
An intersection has a three-phase signal with the movements allowed in each phase and corresponding analysis and saturation flow rates shown in the table below. Assume the lost time is 4 seconds per phase and a critical intersection v/c of 0.90 is desired. Phase 3 Allowed movements NB L, SB L NB T/R, SB T/R EB L, WB L ЕВ TR, WB TR Analy sis flow rate 330, 365 veh/h 1125, 1075 veh/h 110, 80 veb/h 250, 285 veh/h Saturation flow rate 1700, 1750 veh/h 3400, 3300 veh/h 650, 600 veh/h 1750, 1800 veh/h Calculate the sum of the flow ratios for the critical lane groups. 0.787 O 0.857 O 0.709 O 0,829
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Exercise 6 A three phase signal design is given below. ● ● ● Hic Signal What is the sum of the flow ratios for the critical lane groups? What is the total lost time for a signal cycle assuming 2 seconds of clearance lost time and 2 seconds of startup lost time per phase? What is the cycle length using Webster Method? EB - Phase 1 2 3 -200 20 SB 30 100- Lane group SB NB EB WB 400 1000 NB 150 50 300 30 WB Saturation Flows 3400 veh/hr 3400 veh/hr 1400 veh/hr 1400 veh/hr