Gilsonite Usage In Asphalt
Gilsonite (Natural Asphalt) are natural occurring hydrocarbon substances characterized by a high softening point (above 110° C) in the class known as asphaltite. They are mined much like other minerals and sold essentially in their native state. They are fully compatible with asphalt and have long been known as asphalt hardeners and reinforcing agents. Gilsonite is currently sold all over the world as a road bitumen modifier in the form of a dry bulk solid granular powder.
Gilsonite modified road asphalt (GMA) have been particularly successful in highly stressed traffic areas. Natural bitumen, as the majority constituent, has been combined with virgin polymers such as Styrene Butadiene Styrene (SBS) and Ethylene Vinyl Acetate (EVA). GMA binders generally do not increase asphalt binder content requirement in pavement mixtures. It’s modified binders significantly extend the useful life of asphalt pavement.
Gilsonite increases the viscosity of asphalt so roadways resist deformation and fatigue, even under temperature extremes – unlike other modifications or high modulus asphalt based on RAP.
It is generally regarded that Gilsonite reduces pavements’ low temperature properties making them susceptible to thermal cracking. Gilsonite melted into hot asphalt will reduce penetration and increase viscosity of the asphalt binder. Gilsonite may also be mixed with aggregate prior to combining with the asphalt binder.
- Improved resistance to deformation
- Further durability
- prosper economic performance of the road
- retriever for poor aggregates
- Improved resistance to stripping and fatigue
- Compensation for poor mixes design
- Tensile strength – The addition of Gilsonite significantly increased both the unconditioned and moisture-conditioned tensile strength.
Compressive strength – Gilsonite-modified binders showed significant improvement in compressive strength.
Rutting strength – Gilsonite-modified binders significantly increased projected pavement life. In all but one case, adding Gilsonite yielded a ten-fold increase.
Fatigue resistance – The projected pavement life is 1.5 to 5 times longer with the Gilsonite-modified binders.