Harris, Dwayne

Noureldin, Samy

English

Purdue E-Pubs

1NETWORK PAVEMENT EVALUATION USING FWD AND GPR? Dwayne Harris, M.Sc.Samy Noureldin, Ph.D., PE? Research Division – INDOT Objectives:1. Prepare for Full Implementation of AASHTO 2002 (Mechanistic Information)2. Support Pavement Layers Thickness Inventory & Minimize the Need for Coring3. Possible Integration with Pavement Management Thickness Information? - How deep the pavement surface can be  ? milled before resurfacingHMA                                          CompositeRehabilitation StrategiesCoring to Verify Pavement ThicknessNeeds to be MinimizedD2        D1     D3  D4 D5    D6        D7   D8          D9-12            0 8   12 18    24        36   48         60Surface LayerSupport LayerP= 9000 PoundsSubgradeFWDDeflection Bowl is Dependent Upon Thickness & Material Properties• Pavement Stiffness- Center Deflection in mils , 9000 Pounds (40 KN), 68 F (20 C)Interstates     Heavy Traffic     Medium Traffic     Light TrafficExcellent             < 4                  < 5 < 6 < 8Very Good         4 – 6 5 – 7 6 – 8 8 – 10Good 6 – 8  7 – 9                  8 – 10 10 – 12Fair 8 – 10              9 – 11              10 – 12 12 – 14Poor >10 >11                    >12 >14ESALs, Millions  > 30 10 – 30 3 – 10                          < 32GPR  • Ground Penetrating Radar (GPR) pavement relatedtechnology was developed during the SHRP program    • Short wave pulses of electromagnetic energy aretransmitted into the pavement   • These pulses are reflected at each interface back to theradar antenna with the voltage amplitude and arrivaltime that is related to the thickness and materialproperties pavement layers  AntennaSurface LayerSupport LayerSubgradeOGPR Principles? Reflections captured from surface and subsurface layer interfaces? Thickness of surface layer calculated from t1? Amplitudes of reflection strongly influenced by layer moisture content and density? Changes in surface reflection A1used to detect segregation? Changes in base reflection A2  used to detect changes in base moisture contentDielectric ConstantMaterial Mean RangePCC  9 6 – 12Rock 7                         6 – 12 HMA 5 3 – 7Dry Aggregate               7 5 – 9Wet Aggregate             15          10 – 20 Subgrade                      15           5 – 20 Water                             80Air                                   1FWD: AASHTO  T – 256ASTM D 4694GPR: ASTM D 4748Standard Tests11,000    Miles3? FWD Data Collection ? - Truck Lane, Both Bound Directions? - 5 Points/Mile ? - 9000 Pounds Load, 68 F Temperature? GPR Data Collection ? - Truck Lane, Both Bound Directions? - Thickness Picks, at least 5 Points/Mile? Thickness Data? - GPR – FWD – CoresFWD Response Variables  • Normalized Deflection • Subgrade MR & CBR  • Surface Modulus and Layer Coefficient • Support Modulus and Layer Coefficient  • Surface Thickness & Structural Number • Support Thickness & Structural Number • Total Thickness and total Structural Number  • Remaining Life, Years • Overlay Thickness Required I - 69 North Bound Driving Lane0123456789100 20 40 60 80 100 120 140 160Reference Post, MilesNormalized Center Deflection, MilsI - 69 North Bound Driving Lane05101520253035400 20 40 60 80 100 120 140 160Reference Post, MilesFWD Thickness, InchesTotalSurface012345678910I - 64EastI - 64WestI - 65NorthI - 65SouthI - 69North I - 69SouthI - 70EastI - 70WestI - 74EastI - 74WestRoadway Normalized Center Deflection, MilsMaxMinMeanInterstate Comparisons0510152025303540I - 64EastI - 64WestI - 65NorthI - 65SouthI - 69North I - 69SouthI - 70EastI - 70WestI - 74EastI - 74WestRoadwayFWD Thickness, InchesMean TotalMean SurfaceMaxMin4110100100010000SR 1SR 3SR 5SR 19SR 32SR 37SR 49SR 67SR 250US 6US 20US 24US 30US 41RoadwayModulus, KsiSurface Support SubgradeConcrete PavementUS & SR Comparisons330 m m  (13 inches)of HM A overlay overrubblized JRC P305 m m  (12 inches)of concrete overlayover JRCP190 m m  (7.5 inches)of fiber m odified HM Aoverlay over Crackedand Seated JRCPM M  229.1M M  223.4M M  217.2SB NB North toChicagoM M  237.8I – 65 Concrete Section I - 65 North Bound Driving Lane0510152025217 218 219 220 221 222 223 224Reference Post, MilesGPR, Pavement Thickness, Inches 12" Concrete Overlay10" Old JRCPRubblized + HMA SectionI - 65 North Bound Driving Lane0510152025223 224 225 226 227 228 229 230Reference Post, MilesGPR, Pavement Thickness, Inches13" HMA Overlay10" Rubblized JRCP5C&S + HMA SectionI - 65 North Bound Driving Lane 0510152025230 231 232 233 234 235 236 237 238Referenc Post, MilesGPR, Pavement Thickness, Inches 7.5" Fiber Modifed HMA Overlay 10" Cracked and Seated JRCPI - 69 North Bound Driving Lane05101520253035400 20 40 60 80 100 120 140 160Reference Post, MilesPavement Thickness, InchesGPR, Surface Pic 1 GPR, Surface ThicknessFWD, Surface Thickness FWD, Total ThicknessFWD – GPR Thickness Comparisons I - 69 South Bound Driving Lane05101520253035400 20 40 60 80 100 120 140 160Reference Post, MilesPavement Thickness, Inches GPR Surface Pic 1 GPR, Thickness SurfaceFWD, Surface Thickness FWD, Total ThicknessUS - 41 North Bound Driving lane05101520253035400 20 40 60 80 100 120Reference Post, MilesPavement Thickness, Inches GPR, Surface Pic1 GPR, Surface ThicknessFWD, Surface Thickness FWD, Total ThicknessUS - 41 North Bound Driving Lane051015202530354025 30 35 40 45 50Reference Post, MilesPavement Thickness, InchesGPR, Asphalt Thickness GPR, Total ThicknessCore, Asphalt Thickness Core, Total ThicknessConcrete SegmentGPR – Coring Thickness Comparisons6Surface LayerSupport LayerSubgradeO    O     O     OOAntennaFINDINGS & CONCLUSIONS? A pavement thickness and structural capacity inventory of INDOT InterstateHighways was developed. ? INDOT Interstate Highway pavements are currently in a very good structural condition.GPR estimates concrete thickness of concrete pavements, HMA thickness of flexible pavement and HMA thickness of compositepavements almost perfectly. GPR thickness estimation of pavement layers underneath these layers is not as accurateand needs adjustment through very limited coring.GPR did not provide any estimate of unbound pavement layers or total pavement thicknessFINDINGS & CONCLUSIONS? FWD can be used to estimate combined surfacethickness and total pavement thickness. ? Estimate of combined surface thickness matched the GPR estimate in some situation or was slightly lower.? GPR is not expected to completely eliminate the need for coring. GPR can be used to establish the coring requirements to help interpret the GPR data fill the gapsin thickness estimation and verify thickness results.FINDINGS & CONCLUSIONS? Network level testing employing FWD and GPR is a worthwhile, technically sound program that can be integrated in pavement management strategies.? FWD data on 2200 lane miles of the INDOT network is recommended annually for network level pavement evaluation.? Only three FWD tests per mile in the driving lane of one direction are recommended. The information collected will allow the equivalent of 100% coverage of the whole network in 5 years. ? U.S. Roads and State Routes may need more emphasis in network level testing than Interstate Highways.FINDINGS & CONCLUSIONS

Network Pavement Evaluation Using GPR and FWD

https://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1621&amp;context=roadschool

Network Pavement Evaluation Using GPR and FWD

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