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A Review to Develop new Correlations for Geotechnical Properties of Organic Soils

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Abstract

Organic soils are considered one of the most problematic soils due to their high compressibility and low shear strength at small strains. Characterizing organic soils based on their simple index properties is useful for the preliminary design stages of construction projects. There are three main index properties used for assessing organic soils properties, namely: the water content, the organic content, and the fiber content. Organic soils are distinguished by their relatively high water content. The organic content includes the carbonaceous and combustible components. Whereas the fiber content accounts for the presence of fibers in organic soils based on their botanical composition and the degree of decomposition. The data available in literature regarding organic soils parameters (index, compressibility and shear strength) were collected and analyzed in this study to obtain new correlations between the different organic soil parameters, and the simple index parameters (water content and organic content). The available correlations found in the literature depend on relating a certain parameter with either the organic content or water content. However, the organic content and the water content are related. Hence, the proposed correlations presented in this study aim to connect the particular soil parameter with both the water content and the organic content, using the same equation. Unfortunately, there is not much data in the literature about the soil texture or fiber content, and their relation with other parameters. Hence, all the proposed correlations in this study are not considering the fibre content or the soil fabric.

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Acknowledgements

This work was supported by an NSERC CRD (Grant # 11R77115) to Drs. Dharma Wijewickreme and Sumi Siddiqua. The authors would like to thank TransCanada and ConeTec for providing funding, samples and/or in-kind support for this research.

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  1. The University of British Columbia, Kelowna, British Columbia, Canada

    Ahmed ElMouchi & Sumi Siddiqua

  2. The University of British Columbia, Vancouver, British Columbia, Canada

    Dharma Wijewickreme

  3. Delft University of Technology, Delft, Netherlands

    Herbert Polinder

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  1. Ahmed ElMouchi
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Correspondence to Sumi Siddiqua.

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ElMouchi, A., Siddiqua, S., Wijewickreme, D. et al. A Review to Develop new Correlations for Geotechnical Properties of Organic Soils. Geotech Geol Eng 39, 3315–3336 (2021). https://doi.org/10.1007/s10706-021-01723-0

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