Properties of bitumen modified with latex under short-term ageing

Abstract

Short-term ageing is a common issue in bitumen mixing production, and it severely affects the physical, rheological and chemical properties of the bitumen. Polymer modified bitumen is regarded as a preferable paving material to improve the performance of asphalt pavement against binder ageing. One of the additive types used to innovate modified bitumen is natural rubber (latex). This study evaluated the physical properties of bitumen modified with latex under ageing condition. Different percentages of latex (i.e. 2.5%, 5.0%, 7.5% and 10.0%) were added to the control 60/70 penetration grade (PEN) bitumen, which was then tested for penetration, softening point, viscosity, loss on heating and storage stability. The bitumen samples were conditioned under short-term ageing (i.e. rolling thin-film oven) prior to performance tests. Results indicated that modifying bitumen with latex hardens the conventional bitumen 60/70 PEN and potentially improves the bitumen's resistance against temperature susceptibility with a high value of softening point. The addition of latex up to 10% produces a homogenous blend even after short-term ageing condition.