Investigating the preparation and characterization of nano-clay modified asphalts

Abstract

In order to extend the lifespan of flexible pavements materials, a binder quality requests to be modified. The aim of the present research is to assess the physical features of original and modified asphalts with nanoclay materials. These features including; softening point values, penetration grades, viscosity values, penetration index values, and ductility. Three percentages of nanoclay contents (3, 5, and 7) % by of the asphalt weight were blended by a shear blender set at (4000) rpm., and mixing time set about 45 min. at 140 °C. Physical tests results showed that adding nanoclay material as a modifier was beneficial in enhancing the asphalts features. For example, viscosity values and softening point values increase when increase in the nanoclay content. Consequently, the mixing temperatures and compaction temperatures of the modified asphalts increase with increase the nanoclay content to reach (170 °C). While the penetration and ductility values decrease when increase the modifier content. Regarding the penetration index of the modified asphalts, it is enhanced by increase in the nanoclay proportions. Hence, the modified asphalt with 7% of nanoclay produces the greater value of penetration index accordingly, it has a positive influence on the rutting resistance.