New Technologies Land on Airport Pavements Rocky Mountain Asphalt Conference February 18-20, 2009

AAPTP Background Cooperative Agreement FAA & AU Created in 2004 $2million/year $1.6 million for 3 year obtained Organized similar to TRB NCHRP 19 Projects funded Future dependent upon New FAA Legislation in Congress

Obstacles for Technology Lack of experience with technology Aversion to risk Differences between airport and highways FAA lack of encouragement

Technologies Introduced PG Binder Grading (04-02) Superpave (04-03) SMA (04-04) Guidelines for Rubblization (04-01) Longitudinal Joints (04-05)

Projects of Interest HMA Airport Construction Best Practice Manual (05-01) Techniques for Mitigation of Reflective Cracking (05-04) Use of RAP in Airport Pavements (05-06)

Projects Underway Life Cycle Cost Analysis For Airfield Pavements (06-06) Non Coal Tar Based Fuel Resistant Sealers and Binders (05-02) Techniques for Prevention and Remediation of Non-load Related Distresses (05-07 & 06-01) Effect of De-icing Chemical on HMA Airfield Pavements (05-02)

Projects Underway (Cont.) Non-destructive Testing to Identify Presence and Extent of Delamination of HMA Airfield Pavements (06-04) Use of Recycled ASR PCC Materials in HMA (06-02) Guidelines for Use of State DOT Specs (06-05) Performance Base Specs for Airfields (06-3) Assessment of Existing Overlay Design Procedures for Airfield Pavements (06-07)

Change from highways to airfield Considerations for airfield use – Gross vehicle weights – Number of loads – Speed of Loadings – Wander Use of pavement facility Availability of required asphalt grade Project PG Binder Selection

PG Binder Selection Background PG System Design based upon highway traffic and expected temperatures at the pavement site Grades based upon same performance measurement at different temperatures PG represents a binder that provides satisfactory performance at a high temperature of 64 C and at a low temperature of -22C

Binder Performance Grade: PG 52  10  16  22  28  34  40  46 Design high pavement temperature,  C: <52 Design low pavement temperature,  C: >  10>  16>  22>  28>  34>  40>  46 Test on Original Binder Flash Point Temperature (T 48), Min.,  C 230 Viscosity (ASTM D 4402) Maximum value of 3 Pa-s attest temperature,  C 135 Dynamic Shear (TP 5) G*/sin , minimum value 1.00 kPa, at 10 rad/s and Test Temperature,  C 52 Tests on Residue from Rolling Thin Film Oven (T 240) Mass Loss, Maximum, % 1.00 Dynamic Shear (TP 5) G*/sin , minimum value 2.20 kPa, at 10 rad/s and Test Temperature,  C 52 Tests on Residue from Pressure Aging Vessel (PP 1) PAV Aging Temperature,  C 90 Dynamic Shear (TP 5) G* sin , maximum value 5,000 kPa, at 10 rad/s and Test Temperature,  C Physical Hardening Report Creep Stiffness (TP 1) Stiffness, maximum value 300 MPa m-value, minimum value 0.30, at 60 sec ant Test Temperature,  C 0 66  12  18  24  30  36 Direct Tension (TP 5) Failure strain, minimum value 1.0%, at 1.0 mm/min and Test Temperature,  C 0 66  12  18  24  30  36

LTPPBind Software

Procedure – Convert aircraft weights into Equivalent Highway loads (EHE) – Select base temperature from LTPPBind 3.1 – Adjust for traffic and pavement location on facility – Check for availability within US PG Binder Selection

Convert Aircraft to EHE

PG Adjustments Aircraft Stacking Typical Speed MphDesign Traffic EHEs Grade Adjustment  C Runway Centers Taxiways/ Runway Ends Non-Modified Binders Polymer Modified Binders* None  to < 45< 300,0000 Little or none  to < ,000 to < 3 million +7 Not Required +4 3 million to < 10 million +7 Suggested +4  10 million --- Required +4 Occasional---5 to < 15 < 10 million+14 Suggested +11  10 million --- Required +11 Frequent---< 5Any--- Required +17 *Polymer modified binders must have a minimum elastic recovery value of 60 % at 25  C, following procedures described in AASHTO 301.

Check for Availability

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