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?

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?

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/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?
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An intersection has a four-phase signal with the movements allowed in each phase and corresponding analysis and saturation flow rates shown in the table below. Phase Allowed movements Analysis flow rate Saturation flow rate O 116.466 sec O 97.315 sec O 104.693 sec 1 EB L, WB L 245, 230 veh/h 1750, 1725 veh/h Calculate the optimum cycle length (Assume 4 seconds lost time per phase) O 101.399 sec 2 EB T/R, WB T/R 975, 1030 veh/h 3350, 3400 veh/h 3 SB L, SB T/R 255, 235 veh/h 1725, 1750 veh/h 4 NB L, NB T/R 225, 215 veh/h 1700, 1750 veh/h
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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
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 12.105 sec O 15.954 sec O 13.190 sec Phase O 14.127 sec Allowed movements Analysis flow rate Saturation flow rate 1 NB L, SB L 330, 365 veh/h 1700, 1750 veh/h Using v/c equalization ratio, calculate the effective green time for phase 1 2 NB T/R, SB T/R 1125, 1075 veh/h 3400, 3300 veh/h EBL, WBL 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 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 20.464 sec O 22.411 sec O 24.460 sec Phase O 21.035 sec Allowed movements Analysis flow rate Saturation flow rate Using v/c equalization ratio, calculate the effective green time for phase 2 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, WBL 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 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
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