RPA – P1National Airport Pavement Test Facility(NAPTF)

Presented To:  REDAC

By:  Ryan Rutter

Date:  March 2017

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RPA P1 Overview – NAPTF

FY 2016-2017 Accomplishments

Research Goals

Funding Requirements 
        - Research Goals
        - Better prediction of pavement service life
        - Accurate assessment of aircraft-pavement compatibility
        - Validation of performance prediction model for HMA Overlays
        - Milestones
        - Complete Reconstruction of CC8 by the end of summer 2017
        - Complete Phase 5 of the Reflective Cracking Testing by May 2017
        - Complete CC7 Forensic Testing by late summer 2017
        - Complete construction of outside Reflective Cracking slabs by Fall 2017
        - Deliverables
        - Reports, Technical Papers, and databases as required.
        - Standard Operating Procedures developed to help streamline procedures at the NAPTF
        - Construction and completion of testing for Phase 1 of CC8
        - Completion of CC7 traffic testing 
        - Completion of Phase 5 Reflective Cracking reconstruction and the start of testing
        - Reconstruction of the Overlay Section of CC8 Phase 2
        - Subgrade preparation and acceptance for Joint Comparison and Strength/Fatigue sections of CC8 Phase 2

Need

	The National Airport Pavement Test Facility (NAPTF) provides full-scale test data needed to support new FAA design procedures for rigid & flexible pavements.

	RPA P1 funds construction, operations, and maintenance at the NAPTF.  It also funds the Reflective Cracking Project.  
| FY 2017                       | FY 2018 | FY 2019 |
|-------------------------------|---------|---------|
| P1.1 -- Pavement Construction | $928K   | $820K   | $860K |
| P1.2 -- Facility Operation    | $2.21M  | $3.03M  | $3.07M |
| P1.3 -- Facility Maintenance  | $366K   | $213K   | $320K |
| TOTAL                         | $3.5M   | $4.06M  | $4.25M |

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RPA – P1 NAPTF Breakdown

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RPA – P1  NAPTF

P1.1  Pavement Construction

P1.2  Facility Operation

P1.3  Facility Maintenance  

RPA – P1.1  Pavement Construction

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        - Construction money funds both the NAPTF & Reflective Cracking projects
        - CC7 traffic tests complete and forensic trenching by late summer 2017.
        - CC8 Phase 2 reconstruction currently underway
        - CC9 Reconstruction planning underway.  Demolition/reconstruction anticipated by late 2017.
        - Reflective Cracking Phase 5 reconstruction was completed in January 2017.  Phase 6 due to begin in late 2018.
        - Outside reflective cracking slabs to be proposed and built at NAPMRC Facility.
| 2017               | 2018  | 2019  |
|--------------------|-------|-------|
| Construction Money | $928K | $820K | $860K |

RPA – P1.1  Pavement Construction

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CC7 – NORTH PRIMARY OBJECTIVE   
        - Develop Perpetual Pavements Design criterion for airport pavements. 

CC7 – SOUTH PRIMARY OBJECTIVE   
        - Determine allowable overload criteria for flexible pavements.

CC7 North Test Results

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OBSERVATIONS
        - LFP-1N and LFP-2N did not show any evidence of fatigue cracks, LFP-3N and LFP-4N showed severe fatigue cracking. 
        - All top-down cracks. CFP test section LFC-5N showed severe rutting and fatigue cracking. 
        - FOSP strain measurements were useful in understanding the HMA layer behavior. 
        - Laboratory fatigue tests are under progress ; and comparison will be made between predicted and observed fatigue life. 
        - Post traffic trenching will confirm actual HMA layer behavior

PAVEMENT PERFORMANCE

FIBER OPTIC 

STRAIN PLATE (FOSP): 

CC7 South Overload Test Results
        - Traffic testing completed 12/8/16.
        - All failures plotted above the FAARFIELD design failure curve.
        - Clear separation between the three ACN/PCN test items and the three CDF test items.
        - No particular ACN/PCN ratio (up to 50%) caused a qualitative change in pavement behavior after removal of overload.
        - No effect from number of overload wheels.
        - However, limited applications of high strain loads (<1000 coverages to failure) did cause a clear downward shift in the failure curve.
        - Currently preparing overload recommendations for ICAO APEG.

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CC7 Failure Plot

Mixed traffic plotted as equivalent coverages of a reference load:
        - Red = 3 ACN/PCN test items (LFC1-3S)
        - Blue = 3 CDF test items (LFC4-6S)

RPA – P1.1  Pavement Construction

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CC8 OBJECTIVES
        - Overlay Test Area – to evaluate PCC overlay on existing PCC with SCI in 50-80 range.  Determine allowable overload criteria for rigid pavements.
        - Joint Comparison Test Area – Comparison of the performance of Type E and nonstandard sinusoidal keyed longitudinal joints.
        - Strength/Fatigue Test Area – Obtain slab strengths for full scale slabs under load, evaluation of fatigue performance, and evaluation of the effect of fatigue performance of higher strength/thinner slabs versus lower strength/thicker slabs.

CC8 Overlay Test Section

Asphalt Interlayer

P-501 Concrete Placed with Conveyor

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CC8 Overlay Test Section

Concrete Sampling 

PCC Placed in Lanes

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Demolition of Remaining CC6

P- 306 and P-403 Stabilized Base Milled Out

P-154 Subbase Milled Out

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Demolition of Remaining CC6

Subbase – Subgrade Interface Removed

Processing Existing Subgrade to Homogonize

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Issues Encountered 
        - Existing subgrade was not uniform in moisture / CBR.  
        - Water intrusion discovered from separated instrumentation conduit
        - Moisture from subbase
        - Processing subgrade to uniform moisture content – Difficult in Winter to evaporate moisture.	
        - Compensated by mixing dryer sections with wetter sections
        - Equipment Issues
        - Sheared a drive shaft on older smaller tiller – Difficult to get parts
        - Larger tiller sinks in subgrade if tilled more than once

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RPA – P1.2  Facility Operation

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This task includes:

Traffic Testing & Pavement Monitoring

Data Collection, Data Analysis, Databases, and Website content

Reflective Cracking – Phase 5 Testing currently underway

Maintenance -- Test Machine, NAPTF project computers & networks, and all other supporting equipment

NAPTF Upgrades – Design and implementation of new data collection systems
| 2017               | 2018   | 2019   |
|--------------------|--------|--------|
| Facility Operation | $2.21M | $3.03M | $3.07M |

RPA – P1.3  Facility Maintenance

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This task includes:
        - Maintaining the overall building structure and drainage
        - Providing building upgrades to support the testing program
        - Addressing safety issues
        - Building and Power Study completed to identify deficiencies in our 19 year old NAPTF.
        - Deficiencies to be addressed with 2017-2019 funding
| 2017                 | 2018  | 2019  |
|----------------------|-------|-------|
| Facility Maintenance | $366K | $213K | $320K |

RPA P1 - NAPTF

Questions?

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