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Dynamic Late Merge Control Concept

For

Work Zones

On

Rural Freeways

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SPEEDLIMIT

75FINES

DOUBLED

RIGHT LANE

CLOSED 1 MILE

RIGHT LANE

CLOSED 1/2 MILE

REDUCED

SPEEDAHEAD

ROADWORK

2 MILES

FINES FORSPEEDING

DOUBLED INWORK ZONES

ENDROAD WORK

Thank YouDrive Safely

FLASHINGARROW PANEL

SPEEDLIMIT

75FINES

DOUBLED

SPEEDLIMIT

75

SPEEDLIMIT

55FINES

DOUBLED

Conventional Merge TCP

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Basic Approaches

• Early Merge

• Late Merge

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Early Merge

• Static

• Dynamic

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Indiana Lane Merge

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Conventional Merge

Indiana Lane Merge

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Forced Merges

• Indiana: 0.4/hour

• Conventional: 20/hour

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Capacity

• Indiana: 1540 pcph

• Conventional: 1460 pcph

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Late Merge

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USE BOTH LANES

TO MERGE POINT

ROADWORK

1 MILES

LEFT LANECLOSED 1/2 MILE

50MPH

CMS

45MPH

LEFT LANECLOSED 1500 FT

40MPH

LEFT LANECLOSED 1000 FT

40MPH

FlashingArrow Board

MERGE HERE

TAKE YOUR TURN

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Conventional Merge

Late Merge

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Conventional Merge

Late Merge

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Conclusions• Early & Late Merge Performed Better

Than Conventional Merge

• Lower Volumes:

Early Merge May Be Safer

• Higher Volumes:

Late Merge May Be Safer

& More Efficient

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LEDLIGHTS

(SOLAR POWERED)

VEHICLESENSOR ON BACK

EACH SENSOR CONTROLS THENEXT UPSTREAM SIGN'S FLASHERS

DETECTED ZONE FOR

STATION 2

DETECTED ZONE FOR

STATION 3

USE BOTH LANES TO

MERGE POINT

WHENFLASHING

DETECTED ZONE FOR

STATION 1

LEFT LANE RESTRICTION(WORK ZONE)

USE BOTH LANES TO

MERGE POINT

WHENFLASHING

USE BOTH LANES TO

MERGE POINT

WHENFLASHING

USE BOTH LANES TO

MERGE POINT

WHENFLASHING

USE BOTH LANES TO

MERGE POINT

WHENFLASHING

USE BOTH LANES TO

MERGE POINT

WHENFLASHING

Dynamic Late Merge

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Operational Issue

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Research Needed

• Volume Thresholds for Transition Between Early & Late Merge

• Driver Information Needs

• Warrants for Implementation

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