Pavement & Materials TechnologyKeeping America MovingPavement Smoothnessand IRI Ride SpecificationsNorth Central Asphalt UserProducer Group (NCGUPG)Annual MeetingFebruary 19 -20, 20141

Pavement & Materials TechnologyPavement Surface Characteristics3

Pavement & Materials TechnologyKey Areas for SC program Friction / TextureRolling ResistanceNoiseSplash and Spray Smoothness / Ride Quality4

Pavement & Materials TechnologyOutcome – focus on ride qualitySmoothness (IRI), Possible National PerformanceMeasureHighlight team efforts in establishing national/AASHTOstandards in pavement smoothness – need these forpavement condition performance measures.5

Pavement & Materials TechnologyBenefits of Smooth Pavements Satisfied road users Decrease in fuel consumption andvehicle maintenance costs Pavements that are built smootherremain smoother over time and providea longer service life Dynamic loadings are lower on smoothpavements

Pavement & Materials TechnologyInformation on Ride

Pavement & Materials TechnologyProfilograph

Pavement & Materials TechnologyProfilograph ResponseGain2. (ft)1000

Pavement & Materials TechnologyRepresentative Vehicle How many people drive a vehicle with a25 foot wheelbase?

Pavement & Materials TechnologyWho said this? No claim is made that the roughness orriding quality of a pavement is directlyor completely reflected by the profileindex. It should again be emphasized thatstrictly speaking, the devices reportedherein do not furnish a direct index to“riding qualities”.–California Highways and Public Works, Vol. 39 March-April Nos. 3-4, “Profilograph-2” pg 54 Francis N. Hveem, 1960 (inventor of theCalifornia Profilograph)

Pavement & Materials TechnologyPercent Within Limits: PWL Ride Data Efficiently captures mean and standard deviationin one quality measureX - means - standard deviation-3s-2s-1sX1s2s3s

Pavement & Materials TechnologySingle Specification PWL: Use of blanking bandsLSLXPWLLUse of blanking bands of 0.1” and 0.2” cutsoff the lower end of our normal distribution.X

Pavement & Materials TechnologyAdvantages of IRI Reproducible, portable and stable with time General pavement condition indicator Describes roughness that causes vehiclevibrations

Pavement & Materials TechnologyIRI is highly correlated to: Vertical passenger acceleration (Ride Quality) Tire Contact (vehicle control and safety) Output from Response Type RoughnessMeasuring Systems

Pavement & Materials TechnologyProperties of IRI Analysis IRI computed using quarter car model

Pavement & Materials TechnologyComputation of IRI Need longitudinal profile containinginformation relevant to ride Computation of IRI performed by acomputer program as specified in ASTMStandard E1926 Parameters of quarter car (e.g., springstiffness, etc.) referred to as “GoldenCar” parameters

Pavement & Materials TechnologyResponse of IRI to Wavelengths

Pavement & Materials TechnologyInertial Profiler Changes

Pavement & Materials TechnologyPotential Reference Devices

Pavement & Materials TechnologyOverview TPF 5(063) FHWA is lead agency with 22participating State Highway Agencies(SHA’s) FHWA Office of Pavement Technology(HIPT) 1.8 Million 12 Year Study FHWA Long Term Pavement Performance(LTPP) FHWA Federal Lands

Pavement & Materials TechnologyParticipating State Agencies (22)– Ohio– Louisiana– Kentucky– California– Colorado– Florida– Georgia– Kansas– Mississippi– New Jersey– Nevada– New York– North Dakota– South Dakota– Illinois– North Carolina– Maryland– Oklahoma– Connecticut– Texas– Wisconsin– Pennsylvania21 February, 2014

Pavement & Materials TechnologyTPF 5(063) Priorities1. Reference Profile DeviceCritical Requirements - completeBumpfinder Software - completeCertification/Validation SitesEvaluating Upper Limits of SingleAccelerometer – Phase I complete6. Emerging Technology that EnhancesProfile Measurement7. Support RPUG

Pavement & Materials TechnologyProgress on TPF 5(063) Priorities1.Build a Reference Profile Device (ongoing):Two parts –i. Benchmark Testing – UMTRIii. Reference Devices – New round of evaluationsMay 20132.Critical Requirements (completed): UMTRI;final report on pooled fund study website –“Critical Profile Accuracy Requirements”

Pavement & Materials TechnologyTPF 5(063) Priorities - continued3. ProVAL Software: The Transtec Group, Inc. – ProVAL 3.3 released in December 2011– Includes Automated Faulting Module(AFM) ProVAL 3.4 released Dec. 2012 Multiple workshops – 10 annually– Scheduling has started for FY13

Pavement & Materials TechnologyTPF 5(063) Priorities continued4. Certification/Validation Sitei. Study under discussion with FHWA5. Evaluating Upper Limits of SingleAccelerometeri. Phase I: Starodub, Inc. – completeii. Phase II: On hold for publication6. Emerging Technology that EnhancesProfile Measurementi. Urban IRI measurement – FHWAFederal Lands Studyii. Urban and low speed profile indices –NCHRP 10-93

Pavement & Materials TechnologyFHWA Toolkit Smoothness– ProVAL software ( &workshops (10 per year)– ASTM E2560-07: Standard Specification forData Format for Pavement Profile– NHI 131100 “Pavement Smoothness”– AASHTO Ride Quality StandardsImplementation Contract – Assist SHAs M328 Equipment Specification R54 Accepting Ride Quality using an inertialprofiler R56 Certification of Inertial Profilers R57 Operation of Inertial Profilers

Pavement & Materials TechnologyInertial Profilers – Getting Better

Pavement & Materials TechnologyProVAL 3.4 software & workshops

Pavement & Materials TechnologyFrequently Asked Questions Who does the testing, and if not the owner then how doyou certify machine and operator?–Best Practice: SHA for QA & contractor for QC –– SHA certify profilograph and inertial profiler equipment &operators: set up a course & conduct annual equipmentcertification. FHWA assistance available.SHA conduct QA tests on contractor dataWhen is the testing done (daily, once paving complete,or after open to traffic)?–– NH uses average of three runs. TN uses average of five runsQC as soon as possible to monitorQA once paving completeIf not tested generally the day after paving do you knowhow much difference there is by the time the pavementis opened to traffic?–Unsure of studies related to this32

Pavement & Materials TechnologyFrequently Asked Questions What equipment/laser setup are you using for concrete?– AASHTO standards recognize limits of single point lasers.Recommend using line laser that averages across its rangeWhat are the IRI numbers associated withacceptance/incentives? And are they the same for asphalt?–Set by individual SHAs. MS uses same for both ACC & PCC. MNuses combined spec with different thresholds. What bump threshold number do you use for concrete andis it the same as asphalt?– s/2399 2-6-13.pdfSet by each SHA, typically 0.3 inch for either pavement typeWhat do you base your Incentive payments on (set amountper tenth mile or % of a bid price)?–Set by each SHA, many use set amount per tenth mile33

Pavement & Materials TechnologyMnDOT 2013 Combined Spec HMATable 2399-4Smoothness Pay Adjustments and Corrective Work for BituminousPavementsPay Adjustment /0.1 mi [0.16 km]Smoothness in/mi [m/km]Equation 30.0 [0.47]30.0 – 75.0 [0.47 – 1.18]400.00850.00 15.000 Smoothness[850.00 957.450 Smoothness]HMA-A 75.0 [1.18]Corrective Work to 56.7 in/mi [0.89 m/km] 33.0 [0.52]270.0033.0 – 85.0 [0.52 – 1.34]600.00 10.000 Smoothness[600.00 638.950 Smoothness]HMA-B 85.0 [1.34]Corrective Work to 60.0 in/mi [0.94 m/km] 36.0 [0.57]180.0036.0 – 95.0 [0.57 – 1.50]414.00 6.500 x Smoothness[414.00 410.500 x Smoothness]34HMA-C 95.0 [1.50]Corrective Work to 63.7 in/mi [1.01 m/km]

Pavement & Materials TechnologyFrequently Asked Questions Do you use localized roughness in the IRIspecification, if so what are the parameters forPCCP?– Set by SHA and varies: MnDOT uses a continuouslyreported IRI at 125 in/mi for both pavement types What smoothness checks do you use for mid-speedurban areas (40 to 50 mph) and how do youaccomplish it?– Most agencies use ride indices (IRI or PI) for roadwayswith speeds 45 mph If you have an IRI spec, do you still use a PI spec(California Profilograph) in any locations?– Generally not, but some use straightedge for localizedroughness35

Pavement & Materials TechnologyFrequently Asked Questions Use ProVAL or the value the equipment softwareprovides?– Most agencies are specifying ProVAL Are there any additional deducts, besides grinding,to meet a minimum IRI?– Some agencies will remove and replace at high values If ground, can the section be re-profiled to attain asmoothness bonus?– Again varies by agency, some allow others do not Does your state use a combined specification forboth concrete and asphalt, if so do you use thesame equations/IRI specs for both pavementtypes?–Set by each SHA & varies, MnDOT uses 30 in/mi for newACC and 50 in/mi for PCC36

Pavement & Materials TechnologyFrequently Asked Questions Does your state require equipment and/or operatorcertification? Yearly, every x years?–If using contractor data, equipment every year and operatorcertification can vary from 3 to 5 years. MnDOT uses onlinetraining for operators. Do you require ProVAL?– Most agencies do when using IRI and can be used for PrI whencollected with inertial profiler but ProVAL cannot be used for datacollected by profilograph.Do you see an influence on type of pavement texture?– mentsmoothness/Coarse textures i.e. chip seals, tining, OPFC, challenge singlepoint lasers. Line lasers provide viable alternative.Some states set their specs so tight they end up having theentire pavement ground – how do they handle that? Howdo you minimize grinding on the finished project?––Specs can be changed, but most tighten specs after contractorslearn how to build smooth roads.Good construction practices that include daily evaluations of37finished product.

Pavement & Materials TechnologyContact InfoRobert Orthmeyer, FHWA Resource [email protected](708) 283-3533

What equipment/laser setup are you using for concrete? - AASHTO standards recognize limits of single point lasers. Recommend using line laser that averages across its range What are the IRI numbers associated with acceptance/incentives? And are they the same for asphalt? - Set by individual SHAs. MS uses same for both ACC & PCC. MN