Abstract
This study investigated the effects of the addition of a carboxylated styrene–butadiene emulsion (CSBE) and Portland cement on the long-term performance of road base. The specimens stabilised with Portland cement (0–6%) and CSBE (5–10%) were subjected to different stress sequences in order to study the unconfined compressive strength, flexural strength (FS), soaked and unsoaked California bearing ratio, dynamic creep and wheel-tracking characteristics of seven-day-cured specimens. The FS tests showed that the addition of a 4% Portland cement–7% CSBE mixture resulted in improvements of 48.9% of modulus of rupture as compared to the sample with 4% cement. The permanent strain behaviour of the samples was assessed by the Zhou three-stage creep model. The results of dynamic creep and wheel-tracking tests showed that the permanent deformation characteristics were considerably improved by the addition of a 4% Portland cement–7% CSBE mixture, which resulted in reduction of permanent strain of the mixture. Therefore, this research presents a new polymer additive with outstanding engineering properties for use in road bases.
Acknowledgements
The authors would like to thank the Sustainable Urban Transport Research Centre (SUTRA) at the Faculty of Engineering and Built Environment of Universiti Kebangsaan Malaysia (UKM) and Mallard Creek Polymers, Inc. (MCP) for providing research facilities.
Funding
This work was supported by the Universiti Kebangsaan Malaysia [grant number DLP-2014-010].