Session 20 Daniel Furda, Bahareh Saffarian

Daniel Furda, Bahareh Saffarian

Linköpings universitet

Methods for work zone dynamic merge using traffic lights

2

Definition

A segment influenced by works on, near or above it

3

Work zone classifications

• Duration of the work

• Type of the interaction between road and the work zone

• Work intensity

4

Work zone Layouts

• Advanced warning area

• Transition area

• Working(activity) area

• Termination area

Termination Area

Transition Area

Activity Area

Advanced Warning

Area

5

Work zone impacts

Work zone impacts

safety

mobility

Environ-mental

cost

6

Work zone traffic performance analysis

• Mobility analysis( V/C, LOS, travel time delay)

• Safety analysis

• Delay and cost analysis

7

significant influential factors

• Heavy vehicle percentage

• Number of open and close lanes

• Work intensity

• Position of closed lanes

• Weather conditions

• Lane width

• Ramp distance

• Temporary speed limit

• Work zone length

8

Dynamic Merge Systems

Early Merge

Late Merge

9

Experiment

• Microsimulation – Aimsun

• Late merge metering

• Control through traffic lights

10

Calibration of the model

• Driver reaction time = 0,5s

• Driver reaction time at stop = 0,7s 

• Driver reaction time at lights = 0,7s

11

Layout of the work zone

Traffic ligthsOccupancy detectors

20m 100m

12

Assigned flow

0

500

1000

1500

2000

2500

3000

3500

Flow

(veh/h)

Simulation time (min)

15 30 45 60 75

13

Scenarios

• ALINEA metering system

• Fixed cycle times

• Continuous merge metering

14

ALINEA

Traffic ligthsOccupancy detectors

Controler

15

Alinea

Lane 1

Lane 2

4s 3s Variable

Time

16

Fixed cycle times

Cycle time (s)

Time

30 30

60 60

Lane 1

Lane 2

Lane 1

Lane 2

60

120

Lane 1

Lane 2

15 15

30

17

Continuous metering

Lane 1

Lane 2

1

Time

1

18

Fixed cycle times

5 15 25 35 45 55 65 75 850

50

100

150

200

250

300

AlineaFixed 120Fixed 60Fixed 30ContinNo control

5 15 25 35 45 55 65 75 85 950

50

100

150

200

250

300

350

Simulation time (min)

Mean Queue Length (veh)

Simulation time (min)

Delay Time per Vehicle (s)

19

Conclusion

• Extensive sensitivity analisys

• Evaluate the effect of lane-changing restrictions

• Calibration and validation of the model

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