- For about 50 years the paving industry has been trying to take advantage of the elastomeric material and of the carbon black and silica included in recycled tires.
- Those elastomeric materials are know to improve elastic recovery on bitumen. The carbon black and silica improve aggregate interlock.
- A crumb rubber alone cannot be placed directly into the mixes (dry method) in significant qualities because it will swell and absorb the bitumen causing raveling in the roads.
- The wet method (about 20% crumb rubber blended with bitumen and reacted over 1 hour at about 175 C) works well but requires that every contractor buys expensive equipment… around 700 000 USD (only cost effective for large projects)
- If crumb rubber is used in terminal blends it is essentially a waste of product because over time it becomes all digested. Actual improvements on mix properties are only a fraction of what they could be.
- USE OF REACTED AND ACTIVATED RUBBER…that it can be used directly into the plugmillof a contractor’s plant.
- A proper reacted and activated treatment will insure that the rubber is already swelled with bitumen so it will not absorb any more bitumen.
- It will also be treated to blend well and disperse very well and effectively into bitumen
- Large quantities can then be used without any real limitation beyond the need of enough bitumen to wet all surfaces, does really making the binder much more “elastic”.
PDF : RARX_PRESENTATION