WARM ASPHALT MIXTURES Necessity for a thermal approach The case of LEA

1. WARM ASPHALT MIXTURESNecessity for a thermal approach The case of LEA Y.Martineau USIRF LEA-CO 31th MAY 2007

2. Change in coating practiceWarm Mix • Warm or Half-Warm Mixtures ? Warm above 100°C Half-Warm under 100°C • What is the right choice ?

3. Energy conditions the characterisrics and performances of asphalt mixtures An happy influence on environment • The reduction of heating energy produce the same level of reduction on Green House Gas emission Influence of a full or partial, water elimination • A possible non happy influence on the mixture characteristics • Properties for production and placing mixtures • Mechanical performances

4. Warm mixtures : a global approach including, thermal, mechanical and chemical concepts.Use the different physical state of asphalt binder .Chemical additives to minimize the influence of water During mixing, inter-action between physical characteristic, temperature, existing water and mechanical effectAnalysis of thermal content and thermal transfer between components.

5. The basis: Understand thermal ways for heating and drying components Influence of mineral skeleton temperature on heating energy consumption Energy Mineral skeleton temperature

6. Thermal properties of mixture constituents • Cp of aggregate = 0.837 kj/kg/°C • Cp of asphalt binder = 2.093 kj/kg/°C • Cpof water = 4.185 kj/kg/°C • Lv Latent heat of water vaporisation = 2,256 kj/kg • Cvap Sensible heat of water vapor = 1.830 kj/kg

7. Thermal properties of mixture constituentsEnergy content in one ton of each component, at 100°C, from 0°C Yves LE GOFF

8. Functionality of components

9. 130°C HOT COATING COARSE AGGREGATE 90°- 130°C EXPANDED COATING FINE AGGREGATE 100°C 60°- 90°C WORKABILITY WATER/BITUMEN IMMEDIATE STABILITY LEA® a dynamic process < 50°C

10. Heat transfer thermograms during the mixing Core coarse aggr Surface coarse agg Bitumen Water Fine aggregate Temperature in °C Time in secondes

11. LEA-CO 2007

12. LEA-CO 2007

13. The model can be applied to: Laboratory mix design, Industrial production, Industrial quality control, for any type of warm or half-warm mix and hot mix

14. Influence of type of fuel on consumed energy and GGEs

15. The quantity of dust, through the dry filter is reduced of more than 85% • The dry filter can be downsized

16. LEA® Performances • Aspect and characteristics of HMA, but… at 80°C • The same HMA formulas (mineral skeleton and binder content). • Any limitation of binder content. • Definitive mechanical performances, as soon as cooling is achieved. • Mechanical performances of HMA

17. LEA® is a friendly environmental-product • Heating energy savings more than 50% • Reduction of Greenhouse emission, VOC et NOx more than 50% • Improvement of safety and comfort of labours, laying temperature < 90°C • LEA can include recycling • Improvement of safety traffic during works

18. Half-Warm Mix in industrial practices • Use existing Hot Mix Asphalt plants, with complementary equipment • Apply existing standards from Hot Mix Asphalt specs • WMA Quality = HMA Quality Quantity of energy Mix temperature Water content of the mix

19. Right behaviour under trafic

20. Cortland, DOT NY STATE,09/09/2006

21. Cortland,DOT NY State, 09/09/2006

22. Cortland, DOT NY, 09/09/2006

23. Thank you for your attention LEA-co France leaco@fairco.fr 17 rue GUTENBERG 91 620 NOZAY Tel. +33 (0)1 69 63 28 44 Fax. +33 (0)1 69 63 90 52