Optimization of Enzyme-Based Soil Stabilization
Publication: Journal of Materials in Civil Engineering
Volume 32, Issue 5
Abstract
Enzyme-based soil stabilizers have been successfully used in ground applications for the last 30 years. However, the successful application of a given enzyme-based additive is case specific and depends on soil type, soil condition, and operational loads. As a result, contractors incur a substantial cost in terms of time and money for preliminary lab tests, which may determine the suitable mix proportions to utilize in the field application. A sound understanding of the stabilization mechanism of these additives can minimize these costs and yield optimum benefits from the stabilization process. This paper investigates the stabilization effects of a novel enzyme-based additive, commercially known as Eko Soil, that is being applied to construct unpaved roads in Australia and worldwide. The aim of this research is to identify the optimized mix proportions of the additive by unveiling its mechanism of stabilization for a fine-grained field soil, which is dominant in Victoria, Australia. A series of experiments were conducted under a 4-stage test program that included macroscale mechanical tests and microscale imaging tests to unveil stabilization effects and the mechanism of stabilization. The identified mechanism has facilitated enhancement in the efficiency of enzyme-based soil stabilization significantly compared to the strength of nonstabilized soil. The research will substantially benefit the road construction industry by not only replacing traditional construction methods with economical/reliable approaches, but also providing insight on the optimum additive amount required to stabilize road pavements based on this stabilization mechanism.
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Acknowledgments
Financial support from CPEAP Ltd, Australian Research Council, Australia (IH150100006), and Australian Academy of Science under Australia-India Strategic Research Fund fellowship is gratefully acknowledged. The X-ray facility, Microscopy & Microanalysis facility, and scientific and technical assistance provided by RMIT University is further acknowledged. The support provided by EPH to obtain soil for the lab tests is also greatly appreciated.
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Published In
Journal of Materials in Civil Engineering
Volume 32 • Issue 5 • May 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Mar 26, 2019
Accepted: Sep 16, 2019
Published online: Feb 28, 2020
Published in print: May 1, 2020
Discussion open until: Jul 28, 2020
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