# Presentation: 511043

## Innovative Work Zone Traffic Control and Technology

- Mike Fontaine
- Virginia Transportation Research Council
- Making Work Zones Work Better Workshop

## Work Zone Problems

- Capacity reduction
- Increased queuing
- Delays
- Safety
- Crash rate increases 7 to 119 percent
- Rear end crashes most common
- Speeding is often a factor

## Objective

- Describe techniques that could improve safety and/or operations in work zones
- DOT controlled
- Portable
- Cost effective

## Devices Covered

- Worker garments
- Rumble strips
- Radar drones
- Speed displays
- Late merge

## Worker Garments

- Potential camouflage problem
- Evaluated 5 garments
- Field testing inconclusive

## Worker Garment Evaluation

- Luminance (brightness)
- Contrast ratio
- Concrete
- Asphalt
- Vegetation
- Equipment
- Orange TCDs

## Garment Assessment

- Solid fabric garments performed best
- Highest luminance
- Best contrast against variety of backgrounds
- Concerns about comfort in Texas
- Proposed TxDOT vest was the best of the mesh vests
- Does not meet new ANSI standard

## TxDOT Vest Before & After

## Temporary Rumble Strips

- Reduce speeds
- Increase driver awareness

## Temporary Rumble Strips

- 1⁄4 inch thick neoprene strips
- 4 inches wide
- Adhesive backed
- 2 sets of 6 strips installed on work zone approaches
- 18-inch spacings

## Rumble Strips Results

- Evaluated at 2 sites
- 1-2 mph reduction in car speeds
- 3-4 mph reduction in truck speeds
- Not reusable
- Lengthy installation time (40 minutes)
- Noise concerns

## Radar Drone

- Emits K band radar signal
- Intended to simulate enforcement
- 1 mile range
- Approx. $400

## Radar Drone Results

- Evaluated at 3 sites
- 2 mph speed reduction
- Easy to use
- Effectiveness may decline over time

## Speed Display

- Provides motorist feedback on speeds
- Radar drone effect
- $10,000

## Speed Display Features

- 24-inch LED display
- Strobe alert
- Worker alert siren
- Battery powered

## Speed Display Results

- Evaluated at 4 sites
- 5 mph reduction in average speeds
- 10-30% reduction in number of vehicles exceeding speed limit
- Easy to set-up and remove

## Changeable Message Signs with Radar

- Message only displayed to speeders
- 5 mph reduction maintained for 4 months

## Lane Closure Issues

- Problems stemming from lane closures
- Reduced capacity
- Increased travel times
- Increased driver frustration
- Aggressive driving and queue jumping

## The Late Merge Concept

- Late merge
- Utilize all approach lanes to merge point
- Shorter queues
- Possible improved throughput
- More equitable distribution of delay

## Late Merge Applications

- Pennsylvania
- First deployments
- Wide deployment on freeways
- Texas
- Tests in Dallas/Fort Worth
- Freeways
- Virginia
- Tests on primary roads

## Late Merge

## Pennsylvania Late Merge

## Pennsylvania Late Merge

## Virginia Late Merge

## Virginia Late Merge

## Late Merge

- Benefits
- Up to 15% increase in throughput
- 75% fewer forced merges
- 30% reduction in lane straddles
- Reduced queue length
- Potential Limits
- Approach taper at high speeds under low volumes
- Driver understanding
- Use on roads with > 2 lanes

## Summary

- A number of tools are available to improve work zone safety and operations
- Improved worker visibility
- Reduced speeds
- Increased flow

## Questions?

- Mike Fontaine
- _[Michael.Fontaine@VirginiaDOT.org](mailto:Michael.Fontaine@VirginiaDOT.org)_
- (434) 293-1909