PRESENTATION OUTLINE

1. PERMANENT DEFORMATION BEHAVIOR OF THE GRANULAR LAYERS TESTED AT THE FAA’s NATIONAL AIRPORT PAVEMENT TEST FACILITY

2. PRESENTATION OUTLINE • National Airport Pavement Test Facility • Unbound Granular Materials • Measurements • Traffic Tests • Results • Summary

6. 5-inch P-401 Surface 5-inch P-401 Surface 5-inch P-401 Surface 5-inch P-401 Base 5-inch P-401 Base 5-inch P-401 Base 8.5-inch P-209 Subbase 30-inch P-209 Subbase High-Strength Subgrade Medium- Strength Subgrade Low-Strength Subgrade LFS HFS MFS 5-inch P-401 Surface 5-inch P-401 Surface 5-inch P-401 Surface 11-inch P-209 Base 8-inch P-209 Base 8-inch P-209 Base 12-inch P-154 Subbase 36-inch P-154 Subbase High-Strength Subgrade Medium-Strength Subgrade Low-Strength Subgrade HFC LFC MFC 10-inch P-501 Surface 11-inch P-501 Surface 9-inch P-501 Surface 6-inch P-306 Base 6-inch P-306 Base 6-inch P-306 Base 8-inch P-154 Subbase 6-inch P-154 Subbase 8-inch P-154 Subbase Medium-Strength Subgrade High-Strength Subgrade Low-Strength Subgrade MRS HRS LRS NAPTF PAVEMENT CROSS-SECTIONS

7. PRESENTATION OUTLINE • National Airport Pavement Test Facility • Unbound Granular Materials • Measurements • Traffic Tests • Results • Summary

8. P-209 CRUSHED STONE BASE Maximum Dry Density: 141.1 pcf Optimum Moisture Content: 7.10 %

9. P-154 SUBBASE Maximum Dry Density: 128.5 pcf Optimum Moisture Content: 6.5 %

10. SHRP P-46 RESILIENT MODULUS TEST RESULTS

11. PRESENTATION OUTLINE • National Airport Pavement Test Facility • Unbound Granular Materials • Measurements • Traffic Tests • Results • Summary

12. NE-MDD NW-MDD 6-Wheel Traffic Path Low-Strength Subgrade End High-Strength Subgrade End CL-MDD Pavement Center Line 4-Wheel Traffic Path SE-MDD SW-MDD

15. MDD RESPONSE-TIME HISTORY LEFT OFFSET UNRECOVERED DEFORMATION RIGHT OFFSET RECOVERED DEFORMATION TOTAL DEFORMATION PEAK-1 PEAK-2 PEAK-3

19. RUT DEPTH MEASUREMENTS

21. PRESENTATION OUTLINE • National Airport Pavement Test Facility • Unbound Granular Materials • Measurements • Traffic Tests • Results • Summary

22. TRAFFIC TESTS • Vehicle Speed: 5-mph (8-kmph) • Failure Criteria: 1-inch (25-mm) upheaval outside the traffic path • Wheel Load: - 45,000-lbs (20.4 metric tonnes) per wheel - After 20,000 passes @ 45,000-lbs, LFS & LFC further tested @ 65,000-lbs (29.5 metric tonnes)

24. PRESENTATION OUTLINE • National Airport Pavement Test Facility • Unbound Granular Materials • Measurements • Traffic Tests • Results • Summary

26. LFS – LAYER PROFILES

28. LFC – LAYER PROFILES

32. MFC-W – LAYER PROFILES

34. RUT DEPTH MEASUREMENTS

37. MFS-W – LAYER PROFILES

40. MFS-E – LAYER PROFILES

42. PRESENTATION OUTLINE • National Airport Pavement Test Facility • Unbound Granular Materials • Measurements • Traffic Tests • Results • Summary

43. SUMMARY • Of the 6 flexible pavement sections tested- LFS & LFC – Rutting/shoving in P-401 layer, rutting in P-209 & P-154 layer. MFS & MFC – Rutting in subgrade, P-209 & P-154 layer. HFS & HFC – No signs of failure, traffic tests suspended.

44. SUMMARY • The total accumulated permanent deformation in the pavement structure over a complete wander pattern (66 passes) is a small fraction of the total range of the unrecovered deformation occurring during the wander cycle. • Recovered and unrecovered displacements due to traffic loading increased significantly as the pavement was trafficked to failure. http://www.airporttech.tc.faa.gov