Traffic Signals

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Design of Traffic Signal at Bahalgarh Chowk

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Satellite view of Bahalgarh:3

OVERVIEW:

• Traffic signals are controlled devices which could alternatively direct the traffic to stop and proceed at intersection using red and green traffic light signals automatically.

• The main requirements of traffic signals are to draw attention, provide meaning and time to respond and to have minimum waste of time.

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Reduce delayImprove safetyHelp low volume roadsOrderly flow of trafficReduce the frequency of accidents

Traffic Signals – Why?

• Conflicting traffic movements, make roadway intersections unsafe for vehicles and pedestrians

• Intersections are a major source of crashes and vehicle delay (as vehicles yield to avoid conflicts with other vehicles).

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• Most roadway intersections are not signalized due to low traffic volumes and adequate sight distances.

• At some point, traffic volumes and crash frequency/severity (and other factors) reach a level that warrant the installation of traffic signals.

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Traffic Signals : Advantages

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• Ensures orderly movement of traffic in all directions

• Provisions for the progressive flow of traffic in a signal-system corridor

• Provisions for side-street vehicles to enter the traffic stream

• Provisions for pedestrians to cross the street safely

• Potential reduction of accidents, conflicts ensuring safety

• Possible improvements in capacity, and• Possible reductions in delay

Traffic Signals : Disadvantages

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• Large stop time delay• Complex signal design problems

The possible effects of a poorly-timed traffic signal :– increase in vehicle delay,– increase vehicle crashes (particularly rear-end

crashes)– disruption to traffic progression

TYPES OF TRAFFIC SIGNAL:

• Traff ic control signals 1) Fixed-time signal 2) Manually operated signal 3) Automatic signal• Pedestrian signal• Special traffic signal

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Requirement of traffic signal Warrants for traffic control signal installation recommended by IRC Analysis of traffic volume Design of traffic signal by following methods: Approximate method IRC method Check by webster’s method

METHODOLOGY

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130144 53

187112 60

367660104

67860130

Analysis of Traffic Volume:

4:00-4:30

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166174 76

247148 80

292786108

50775145

4:30-5:00

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188196 71

202146 76

334834101

72883165

5:00-5:30

15

179182 67

191157 59

35184294

77852148

5:30-6:00

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6:00-6:30

152165 69

173146 64

352841107

56827180

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153201 70

177148 60

35784780

49811147

6:30-7:00

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160201 68

211166 88

304767119

77753171

2:00-2:30

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146149 61

186119 66

30373197

53790108

2:30-3:00

Thank You

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