Innovative Work Zone Traffic Control and Technology Mike Fontaine Virginia Transportation Research Council Making Work Zones Work Better Workshop

Work Zone Problems Capacity reductionCapacity reduction –Increased queuing –Delays SafetySafety –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 zonesDescribe techniques that could improve safety and/or operations in work zones –DOT controlled –Portable –Cost effective

Devices Covered Worker garmentsWorker garments Rumble stripsRumble strips Radar dronesRadar drones Speed displaysSpeed displays Late mergeLate merge

Worker Garments Potential camouflage problemPotential camouflage problem Evaluated 5 garmentsEvaluated 5 garments Field testing inconclusiveField testing inconclusive

Worker Garment Evaluation Luminance (brightness)Luminance (brightness) Contrast ratioContrast ratio –Concrete –Asphalt –Vegetation –Equipment –Orange TCDs

Garment Assessment Solid fabric garments performed bestSolid 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 vestsProposed TxDOT vest was the best of the mesh vests –Does not meet new ANSI standard

TxDOT Vest Before & After

Temporary Rumble Strips Reduce speedsReduce speeds Increase driver awarenessIncrease driver awareness

Temporary Rumble Strips ¼ inch thick neoprene strips¼ inch thick neoprene strips 4 inches wide4 inches wide Adhesive backedAdhesive backed 2 sets of 6 strips installed on work zone approaches2 sets of 6 strips installed on work zone approaches 18-inch spacings18-inch spacings

Rumble Strips Results Evaluated at 2 sitesEvaluated at 2 sites –1-2 mph reduction in car speeds –3-4 mph reduction in truck speeds Not reusableNot reusable Lengthy installation time (40 minutes)Lengthy installation time (40 minutes) Noise concernsNoise concerns

Radar Drone Emits K band radar signalEmits K band radar signal Intended to simulate enforcementIntended to simulate enforcement 1 mile range1 mile range Approx. $400Approx. $400

Radar Drone Results Evaluated at 3 sitesEvaluated at 3 sites 2 mph speed reduction2 mph speed reduction Easy to useEasy to use Effectiveness may decline over timeEffectiveness may decline over time

Speed Display Provides motorist feedback on speedsProvides motorist feedback on speeds Radar drone effectRadar drone effect $10,000$10,000

Speed Display Features 24-inch LED display24-inch LED display Strobe alertStrobe alert Worker alert sirenWorker alert siren Battery poweredBattery powered

Speed Display Results Evaluated at 4 sitesEvaluated at 4 sites 5 mph reduction in average speeds5 mph reduction in average speeds 10-30% reduction in number of vehicles exceeding speed limit10-30% reduction in number of vehicles exceeding speed limit Easy to set-up and removeEasy to set-up and remove

Changeable Message Signs with Radar Message only displayed to speedersMessage only displayed to speeders 5 mph reduction maintained for 4 months5 mph reduction maintained for 4 months

Lane Closure Issues Problems stemming from lane closuresProblems stemming from lane closures –Reduced capacity –Increased travel times –Increased driver frustration –Aggressive driving and queue jumping

The Late Merge Concept Late mergeLate merge –Utilize all approach lanes to merge point –Shorter queues –Possible improved throughput –More equitable distribution of delay

Late Merge Applications PennsylvaniaPennsylvania –First deployments –Wide deployment on freeways TexasTexas –Tests in Dallas/Fort Worth –Freeways VirginiaVirginia –Tests on primary roads

Late Merge

Pennsylvania Late Merge

Virginia Late Merge

Late Merge BenefitsBenefits –Up to 15% increase in throughput –75% fewer forced merges –30% reduction in lane straddles –Reduced queue length Potential LimitsPotential 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 operationsA number of tools are available to improve work zone safety and operations –Improved worker visibility –Reduced speeds –Increased flow

Questions? Mike Fontaine (434)