Study On The High Temperature Performance Of Bio Modified Rubber Asphalt (Bmr)

Amadou M. Bocoum, North Carolina Agricultural and Technical State University

Abstract

The objective of this study is to produce an environmentally friendly paving material with enhanced high temperature performance. To do so, feasibility of synthesis an alternative asphalt binder from scrap tire rubber and bio-binder is investigated in this paper. The newly developed bio modified rubber is a hybrid viscoelastic thermoplastic adhesive composed of ambient crumb rubber and bio-binder. Bio-binder is produced from thermochemical conversion of swine manure, and crumb rubber is obtained from grinding of scrap tire. It should be emphasized that the aforementioned ingredients are derived from waste materials. Using crumb rubber as paving material can alleviate problems facing the solid waste management industry related to disposal of scrap tire. On the other side, production of bio-binder reduces the need of lagoons to store swine manure, and decreases noxious odor originating from swine manure stored in lagoons. This study concentrates on the high temperature properties and temperature susceptibility of the bio modified rubber. To develop bio-modified rubber bio-binder were mixed with various percentages of ambient crumb rubber 80 mesh (0.177mm) ranging from 5 up to 50% by the weight of asphalt binder. Dynamic shear rheometer (DSR) was employed to measure the complex modulus (G*) and phase angle (δ) of un-aged and aged bio-modified rubber. Aging was conducted using rolling thin film oven (RTFO). The rotational viscometer (RV) was used to quantify the bio-modified rubber binder's high temperature properties and pump-ability. It was found that bio-modified rubber binder's viscosity decreases by increasing the bio-binder percentages at specified temperature. In addition, the increase of bio-binder percentages showed to improve temperature susceptibility and resistance to rutting. As such it was concluded that alternative asphalt with enhanced high temperature properties could be produced using scrap tire and bio-binder rubber.