Susceptibility of low-density polyethylene and polyphosphoric acid-modified asphalt binders to rutting and fatigue cracking

Fatigue and rutting properties of asphalt binders modified with low-density polyethylene and polyphosphoric acid (PPA) were investigated. The modifier contents were chosen such that the high-temperature performance grade is the same for all formulations in the Superpave® specification (PG 76-xx). The linear amplitude sweep (LAS) for fatigue and the multiple stress creep and recovery (MSCR) for rutting were performed. The modified binders have better rheological properties than the base material and show different rutting and fatigue behaviors, even though their high PG grades are the same. The results indicated that PPA is a great alternative to be used as binder modifier.