The use of a polyethylene-based modifier to produce modified asphalt binders on site

Modified asphalt binders are commonly employed to reduce severity of flexible pavement distresses and increases service life. In some countries, modified binders need to be imported from abroad. Further problems may arise due to the geographical location of the plants (e.g. desert areas or areas with low industrial development), as well as to the economic inconvenience in the supply of raw materials necessary for small processes. This study focuses on the investigation of a technology that allows the production of modified binder directly on site by adding a polyethylene-based-modifier during the mixing stage. Eight different mixtures were prepared combining two different asphalt binders, neat and SBS modified, together with the modifier and RAP material. The mechanical and energy properties of the mixes were investigated performing the SuperPave IDT test. The results showed significant mechanical improvements for neat asphalt mixtures combined with the modifier, showing a decrease of the rate of damage accumulation and an increase in energy thresholds. A more critical interpretation was obtained when the modifier was added to SBS modified mixtures.