Effect of Interaction Parameters on the Hardness and Elastic Modulus of Crumb Rubber Modified Asphalt


Instrumented indentation presents an approach to measure the mechanical properties such as hardness and elastic modulus of materials on micro and nano scale. This gives an idea about the behavior of materials during their application when they are laid as layers of thickness of the nano or micro scale level. Two advantages can be achieved from the utilization of instrumented micro-indentation on crumb rubber modified asphalt; the first would be to measure the properties of asphalt layers of thicknesses on the micro scale to simulate the behavior of thin asphalt layer on aggregate. The second advantage would be to investigate the effect of interaction (blend processing) synthesis parameters (mixing speed, temperature and time) on the final product hardness and elastic modulus. Through the current work, it was found that the interaction parameters play a major role on the determination of the hardness and elastic modulus of crumb rubber modified asphalt (CRMA). The utilization of moderate (30Hz) to high (50Hz) interaction speeds at low interaction temperature (160°C) resulted in minimal enhancements in both the hardness and elastic modulus. On the other hand, the utilization of moderate (190°C) interaction temperature with high interaction speed (50Hz) resulted in major property enhancements for both the hardness and elastic modulus. At 220°C interaction temperature, deterioration in both the hardness and elastic modulus was observed after 4 hrs ofinteraction time regardless of the interaction speed utilized.


Civil, Architectural and Environmental Engineering

Keywords and Phrases

Crumb Rubber Modified Asphalt; Interaction Parameters; Microindentation

Document Type

Article - Journal

Document Version


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© 2015 Chinese Society of Pavement Engineering, All rights reserved.

Publication Date

01 Jan 2015