1. at Auburn University Strategies for Design and Construction of High-Reflectance Asphalt Pavements Nam Tran, Buzz Powell, Howard Marks, Randy West and Andrea Kvasnak

2. at Auburn University Outline Urban heat island (UHI) effects Cool pavements and LEED credits SRI and how to measure

3. at Auburn University Background Source: EPA – Cooling Summertime Temperatures

4. What Causes Heat Islands? Source: www.DigitalWorldTokyo.com Trap hot air and reduce wind flow Replace trees with buildings & infrastructures

5. at Auburn University How to Reduce UHI? More trees Reflective and green roofs Cool pavements Efficient cooling systems U of Washington ACROS Fukuoka, JP Ennis Paint

6. at Auburn University How to be “Cool” and Get Awards According to LEED, cool pavement strategies include: –Shading hard surfaces –Using high-reflectance materials –Using open grid or porous pavements LEED awards: –1 credit for “New” and “School” projects for 50% coverage using cool pavements –1 credit for 25%, 2 credits for 50%, and 3 credits for 75% coverage for “Retail” projects

7. at Auburn University Solar Reflectance Index (SRI) A function of reflectance and emittance – –SRI = 100 for standard white surface –SRI = 0 for standard black surface –Reflectance has profound effect on SRI –More information in ASTM E 1980 Higher SRI, lower surface temperature

8. at Auburn University How to Measure Reflectance Field –ASTM E 1918 –Equip.: ~ $2,000 –Mat: 10 ft x 10 ft Laboratory –ASTM C 1549 –Equip.: ~ $30,000 –Core: 6 in. dia

9. at Auburn University Asphalt vs. Concrete Have similar SRI as they get older

10. at Auburn University Thank You