RFID Applications for Asphalt Pavements. Charles W. Schwartz University of Maryland AASHTO Subcommittee on Materials Anchorage, AK August 2009

Transcription

1 RFID Applications for Asphalt Pavements Charles W. Schwartz University of Maryland AASHTO Subcommittee on Materials Anchorage, AK August 2009

2 Radio Frequency Identification (RFID) Computer Antenna Tag ID Power to Transmitter Antenna RF Power Tag Activated by Transmitter RF RFID Reader Tag ID from Receiver Antenna Tag ID Passive RFID Tag

3 Application Areas Inventory Control Tools/Equipment Vehicles Material Tracking Test Specimens Stockpiles In-place Sensing Temperature Strain Others Detection Cracking

4 Application Areas Inventory Control Tools/Equipment Vehicles Material Tracking Test Specimens Stockpiles In-place Sensing Temperature Strain Others Detection Cracking

5 Tracking: The Problem AC AC Link?? Distress Milepoint Lot Lot Pavement Construction Pavement Management

6 The Solution? HMA from Plant Haul Truck Paver Encapsulated RFID Tag Tags scanned when convenient after construction Compaction Vehicle with RFID Reader and GPS Finished Pavement

7 Selected RFID Technology Passive UHF (~900 MHz) Tags 2x2 inch Alien 1x1 inch Alien 1x2 inch UPM Raflatac

8 Tag Encapsulation CPVC pipes (11/16 internal diameter) Tags placed along inside of pipe wall Pipe filled with hightemperature epoxy Cost ~$1 each Epoxy Epoxy-filled CPVC pipe Tag along inner surface of pipe wall Hollow CPVC pipe

9 Laboratory Evaluation Gyratory Plug Containing Encapsulated Tags Antenna 67% survival rate Some degradation over time Read range: ~1 meter Encapsulation process later improved

10 Field Trials: UMD Lot EE 1x1 tag (10 total) 2x2 tag (20 total) 2x2 tag (10 total) Pre-Positioned Tags 1x1 tag (20 total) Through-Paver Tags 12.5 mm HMA surface, 50 mm thick 19 mm HMA base, 100 mm thick

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12 UMD Field Trial Results 100% 2x2 Base 2x2 Surface 2x2 All Read Success Rate 80% 60% 40% 20% 1x1 Base 1x1 Surface 1x1 All All 10 antenna height 0% Detection on basis of Layer/Course Lot EE

13 Tag Surfacing 2x2 Tag 2x2 Tag 1x1 Tag Tag surfacing in Lot EE: 1x1 tags: 20% 2x2 tags: 40% (Surface lift tags only)

14 Hampstead Bypass Field Trial MD 30 NW of Baltimore New alignment: 4.4 miles, 2 lanes 2 surface lift over two 4 base lifts (19 mm) Staged construction

15 Hampstead Bypass Field Trial November 2007 Lower 4 base lift (19 mm) 40 UPM Raflatac 1x2 tags, 60 Alien 2x2 tags (10/truck) No MTV

16 C.J. Miller Paving

17 Vehicle speed: < 5 mph Antenna height: 3 and 12 Other variables: - Vehicle speed - Antenna height - Antenna configuration

18 Read Success Rate Hampstead Bypass 100% Percentage of Tags Read 80% 60% 40% 20% 17.5% 56.7% 17.5% 66.7% 2x2 0% 3in 1x2 Tag Dimension 12in Antenna Height

19 Tag Surfacing Rates: 1x2: 0% 2x2: 15%

20 Hampstead Bypass Field Trial April 2008 Upper 4 base lift (19 mm) 32 Alien 2x2 tags (8/truck) MTV

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22 Tag Spatial Sequence Variable (unknown) spatial lag Mixing in MTV surge hopper

23 Read Success vs. Speed 100% Read Success (Relative to 0 mph) 80% 60% 40% 20% 0% Vehicle Speed (mph)

24 Tag Longevity 2x2 Tags - Lower Base Lift (November 2007) 100% Read Success Rate 80% 60% 40% 20% 0% Nov 07-3" Nov 07-12" Apr 08-3" Read Date and Antenna Height

25 Surfaced Tags 106 density measurements for 7 tag (July 29, 2009) (Permeability still TBD)

26 Technology Advances Titan Tag (Summer 2008) Small size 1.5 x 0.44 x 0.11 inches Durable FR4 flame retardant PCB laminate Up to 200 o C, 200+ psi, high humidity, mechanical shock No need for encapsulation Survives paving simulation in lab Read range/performance?

27 Related Applications Field trials with NYDOT planned for this fall.

28 Sensing: Temperature Intelligent Compaction

29 Surface Acoustic Wave (SAW) RFID (Animation at

30 Patch Monopole 2 Deg. Celcius Tag 0443 Monopole Time (mins) Deg. Celcius Tag Fluke Patch Tag 09FE Time (mins) Tag Fluke Laboratory Evaluation

31 Field Trials US15 / US340 SW of Frederick MD July 21-22, 2009

32 Field Trials

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34 100 Group B - E - G - I Temp. Profile, Bottom of Mat (Very) Temperature (Deg. Celcius) Pass 1 Pass 2 Pass 3 Pass 4 Group B - E - G - I Temp. Profile, Middle of Mat Preliminary Results Temperature (Deg. Celcius) Distance Along Test Alignment (Feet) Pass 1 Pass 2 Pass 3 Pass 4 Group B - E - G - I Temp. Profile, Top of Mat Temperature readings from ~60% of tags Distance Along 90 Test Alignment (Feet) Temperature (Deg. Celcius) Distance Along Test Alignment (Feet) Pass 1 Pass 2 Pass 3 Pass 4

35 Detection: Reflection Cracking Frangible Conductive Links Work is in very preliminary stage

36 Conclusions HMA production tracked successfully in field using RFID technology Minimal interference with paving operations No projection of tags above mat surface Surfacing of tags being investigated further Adequate to good read success rate Range sufficient for bumper-mounted antenna array 2x2 tags: 60-80% read success rate or higher Need improvement for smaller tags

37 Ongoing Work Evaluation of surfaced tags Local density Local permeability Evaluation of smaller format Titan tags Tracking of PCC placement Sensor applications Temperature Mechanical strains Detector applications Reflection cracking Guidance on data integration

38 0.20 Benefit: Added Value to Data Rut Depth (in) AC (%) Pavement Management Construction Milepoint Milepoint

39 Contact Info: Dr. Charles W. Schwartz University of Maryland