Innovative Work Zone Traffic Innovative Work Zone Traffic Control and TechnologyControl and Technology

Mike FontaineMike FontaineVirginia Transportation Research Virginia Transportation Research

CouncilCouncil

Making Work Zones Work Better Making Work Zones Work Better WorkshopWorkshop

Work Zone ProblemsWork Zone Problems

• Capacity reductionCapacity reduction– Increased queuingIncreased queuing– DelaysDelays

• SafetySafety– Crash rate increases 7 to 119 percentCrash rate increases 7 to 119 percent– Rear end crashes most commonRear end crashes most common– Speeding is often a factorSpeeding is often a factor

ObjectiveObjective

• Describe techniques that could improve Describe techniques that could improve safety and/or operations in work zonessafety and/or operations in work zones– DOT controlledDOT controlled– PortablePortable– Cost effectiveCost effective

Devices CoveredDevices Covered

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

Worker GarmentsWorker Garments

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

Worker Garment EvaluationWorker Garment Evaluation

• Luminance (brightness)Luminance (brightness)• Contrast ratioContrast ratio

– ConcreteConcrete– AsphaltAsphalt– VegetationVegetation– EquipmentEquipment– Orange TCDsOrange TCDs

Garment AssessmentGarment Assessment

• Solid fabric garments performed bestSolid fabric garments performed best– Highest luminanceHighest luminance– Best contrast against variety of Best contrast against variety of

backgroundsbackgrounds– Concerns about comfort in TexasConcerns about comfort in Texas

• Proposed TxDOT vest was the best of Proposed TxDOT vest was the best of the mesh veststhe mesh vests– Does not meet new ANSI standardDoes not meet new ANSI standard

TxDOT Vest Before & AfterTxDOT Vest Before & After

Temporary Rumble StripsTemporary Rumble Strips

• Reduce speedsReduce speeds• Increase driver Increase driver

awarenessawareness

Temporary Rumble StripsTemporary 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 2 sets of 6 strips installed on work zone

approachesapproaches• 18-inch spacings18-inch spacings

Rumble Strips ResultsRumble Strips Results

• Evaluated at 2 sitesEvaluated at 2 sites– 1-2 mph reduction in car speeds1-2 mph reduction in car speeds– 3-4 mph reduction in truck speeds3-4 mph reduction in truck speeds

• Not reusableNot reusable• Lengthy installation time (40 minutes)Lengthy installation time (40 minutes)• Noise concernsNoise concerns

Radar DroneRadar Drone

• Emits K band radar Emits K band radar signalsignal

• Intended to simulate Intended to simulate enforcementenforcement

• 1 mile range1 mile range• Approx. $400Approx. $400

Radar Drone ResultsRadar 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 DisplaySpeed Display

• Provides motorist Provides motorist feedback on speedsfeedback on speeds

• Radar drone effectRadar drone effect• $10,000$10,000

Speed Display FeaturesSpeed Display Features

• 24-inch LED display24-inch LED display• Strobe alertStrobe alert• Worker alert sirenWorker alert siren• Battery poweredBattery powered

Speed Display ResultsSpeed 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 10-30% reduction in number of vehicles

exceeding speed limitexceeding speed limit• Easy to set-up and removeEasy to set-up and remove

Changeable Message Signs Changeable Message Signs with Radarwith Radar

• Message only Message only displayed to displayed to speedersspeeders

• 5 mph reduction 5 mph reduction maintained for 4 maintained for 4 monthsmonths

Lane Closure IssuesLane Closure Issues

• Problems stemming from lane closuresProblems stemming from lane closures– Reduced capacityReduced capacity– Increased travel timesIncreased travel times– Increased driver frustrationIncreased driver frustration– Aggressive driving and queue Aggressive driving and queue

jumpingjumping

The Late Merge ConceptThe Late Merge Concept

• Late mergeLate merge– Utilize all approach lanes to merge Utilize all approach lanes to merge

pointpoint– Shorter queuesShorter queues– Possible improved throughputPossible improved throughput– More equitable distribution of delayMore equitable distribution of delay

Late Merge ApplicationsLate Merge Applications

• PennsylvaniaPennsylvania– First deploymentsFirst deployments– Wide deployment on freewaysWide deployment on freeways

• TexasTexas– Tests in Dallas/Fort WorthTests in Dallas/Fort Worth– FreewaysFreeways

• VirginiaVirginia– Tests on primary roadsTests on primary roads

Late MergeLate Merge

Pennsylvania Late MergePennsylvania Late Merge

Pennsylvania Late MergePennsylvania Late Merge

Virginia Late MergeVirginia Late Merge

Virginia Late MergeVirginia Late Merge

Late MergeLate Merge

• BenefitsBenefits– Up to 15% increase in throughputUp to 15% increase in throughput– 75% fewer forced merges75% fewer forced merges– 30% reduction in lane straddles30% reduction in lane straddles– Reduced queue lengthReduced queue length

• Potential LimitsPotential Limits– Approach taper at high speeds under low Approach taper at high speeds under low

volumesvolumes– Driver understandingDriver understanding– Use on roads with > 2 lanesUse on roads with > 2 lanes

SummarySummary

• A number of tools are available to A number of tools are available to improve work zone safety and improve work zone safety and operationsoperations– Improved worker visibilityImproved worker visibility– Reduced speedsReduced speeds– Increased flowIncreased flow

Questions?Questions?

Mike FontaineMike Fontaine

Michael.Fontaine@VirginiaDOT.orgMichael.Fontaine@VirginiaDOT.org

(434) 293-1909(434) 293-1909