The effects of Macro and Nanoclay on bitumen rheology

The exponential growth of the pavement industry over the decades, together with increasing traffic loads and volumes, are the main contributors to the need for binder modification. For this reason, polymers such as styrene butadiene rubber (SBR) and styrene butadiene styrene (SBS) have long been utilized as binder performance modifiers.

Even so, researchers have continued seeking more affordable alternative modifying materials due to the high cost of these polymers. Nanotechnology is a field that could make it possible to achieve impactful modifications to the asphalt binder. Accordingly, nanoclay has been put forward as a suitable alternative by researchers because of its natural abundance and economic benefits. The addition of small amounts of nanoclay has been reported to enhance properties such as stiffness, rutting resistance, low-temperature cracking resistance and storage stability. Oxidation, ageing susceptibility reduction and further advantages are expected in the long-term performance of the asphalt.

This study assesses the effects of nanoclay modification on the short- and long-term performance of the binder and the effects of macro vs. nanoclay modification on the rheology of the binder.

About the Author

Mookgo Sephooko completed her B Tech: Engineering Civil in 2011 and her N Dip: Civil Engineering in 2012, both at the Central University of Technology. She is currently completing her MSc degree on the topic of Nanomaterials modification of asphalt binders and Mastic Asphalt at the University of KwaZulu-Natal. Mookgo has been a Junior Lecturer at the University of South Africa for the past two years. Prior to that she obtained experience in the field at eThekwini Municipality, Sam’s Mega Connections, and Bigen Africa Services, as well as standards writing at the SABS, and working as a Technical Assistant at the Central University of Technology.