Using rice husks powder to upgrade the rheological properties of bitumen binder

Oxidative aging is one of the main concern issues in the asphalt binder technology nowadays. Oxidation drives the bitumen to be harder and eventually cracked under high loads. Many researches have been tried to improve the resistance of asphalt pavement to rutting and cracking. The objective of this study is to investigate the influence of adding rice husks powder to the asphalt binder, on its physical and rheological properties. Three percentages (5%, 10% and 12%) of rice husks were used as modifiers. The influence of rice husks on the conventional properties, complex modulus (G*), cracking parameters and rutting parameters were investigated. Therefore penetration and rheological tests using a dynamic shear rheometer (DSR) were carried out to characterize the rice husksmodified bitumen. Based on the results obtained from the conventional properties tests and rheological tests, rice husks reduces the temperature susceptibility and increases the viscosity, stiffness and elastic behavior of the rice husks-modified bitumen. Rice husks enhanced rutting resistance and fatigue resistance of the bitumen at high temperatures and low temperatures. The best results were recorded for rice husks-modified bitumen containing 10% of rice husks.

Jarosław Górecki