Evaluation of rheological behavior of asphalt binder modified by recycled polyethylene wax and crumb rubber

Abstract

As in recent years the disposal of waste tire rubbers in landfills are increased because of increase in population, the environmental population are increased. The recycle and reuse of these material to modify bitumen can be environmentally and economically beneficial. In current research the polyethylene wax and Crumb Rubber are used to modify original binder. Several bitumen tests were used to evaluate the rheological properties of binder such as; Multiple Stress and Creep Recovery (MSCR) and Linear Amplitude Sweep (LAS), dynamic shear rheometer (DSR), bending beam rheometer (BBR), rotational viscosity. Results revealed that samples modified by 18% crumb rubber and 5% polyethylene wax have better performance to save energy and reduce air pollution. Results indicated that addition of polyethylene wax led to decrease in the performance of binder in low temperature, while CR enhance it. Fatigue test results indicated that addition of CR increased the fatigue life of binder, while as the polyethylene wax content increased, the fatigue lives decreased. MSCR test results indicated that CR improves the recovery potential of binder which lead to enhance the rutting properties of binder. Based on results in 15% CR modified binders, addition of 3% polyethylene wax improves the resistance against permanent deformation while addition of 5% and 7% polyethylene wax reduces the rutting resistance of binder. While in binder modified by 18% and 21% CR, addition of 3% and 5% polyethylene wax enhance the permanent deformation resistance of binder and addition of 7% polyethylene wax decreases the rutting performance.