Assessment of Mechanical Properties of HMA modified by EVA


Asphalt become plastic material with the high temperature effect, so it describes as thermoplastic material, the polymers was used to enhance asphalt properties in mean of increasing the temperature range over which it resists both rutting and thermal cracking; the polymers like EVA has been widely used to increase both the workability of the asphalt during compaction and its resistance to deformations in service. Hot Melt Glue is type of thermoplastic adhesive containing the EVA copolymer with Terpene-Phenol Resin (TPR) tackifier. The used asphalt was from the crude oil refinery of Al-Nasiriya (southern of Iraq) its classified grade (60-70), is used with deferent percentages of the Hot Melt Glue. Two stages of work plan were adopted: the first was to study the effect of the Glue on asphalt then at the second stage Glue effect on the asphalt mixture. Tests like penetration, softening point and ductility of asphalt, and resistance to flow (stability & flow) by Marshall Method (for mix) were adopted in this research. The results show that the Hot Melt Glue reduces the penetration and specific gravity of the asphalt, on the other hand the softening point increased with increasing of the Glue. There is a little increasing of the susceptibility to high temperature with increasing of the glue (to 2%) then begin to degrease with increase the glue. There is significant decreasing in ductility with the increasing of the glue and after the percent 2.5 the ductility reduced less than requirements of specification (100 cm). The flash point not influenced with increasing of glue till 6%. The Marshall Stability increases while the flow decreases with the increasing the Glue. There is a little reduction in density and air voids with increasing of the glue.