Abstract
Compared to manufactured materials, soil properties often exhibit significant variability even within a seemingly homogeneous soil layer. The uncertainty related to this variability can be dealt in a robust manner by means of reliability-based methods. Hence, effort has been made to collect soil statistics in order to provide approximate guidelines for selecting the value of coefficient of variation (COV) of inherent variability. It has been observed that the COV value for the same physical property tends to vary within a relatively narrow range, meaning that the literature COV ranges could be utilized with some confidence on sites which lack sufficient soil data. However, it is not certain whether these prior COV values can be used in Finland since many Finnish clay soils are soft and sensitive due to their unique geological history shaped by the last post-glacial processes. Hence, this paper evaluates the inherent variability of various geotechnical properties (index, strength and consolidation properties) in four clay soil sites located in Southern Finland. Besides prior ranges of COV, this paper provides prior ranges of the mean soil property, applicable for soft post-glacial clays and clayey gyttjas. Furthermore, the shape of the probability distribution is evaluated for various soil properties at one clay site by means of normality tests and visual assessment. It is concluded that the derived COV values are in accordance with literature ranges, but for more reliable estimates, soil statistics derived for Finnish clay soils should be preferred when possible. Nonetheless, no literature range can replace extensive site-specific soil statistics. Finally, it is confirmed that nearly all the soil properties at the studied Finnish clay site can be modelled as normal or lognormal distribution.
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References
Phoon, K.-K., & Kulhawy, F. H. (1999). Characterization of geotechnical variability. Canadian Geotechnical Journal, 36, 612–624.
Phoon, K.-K. (2017). Role of reliability calculations in geotechnical design. Georisk, 11, 4–21.
Lacasse, S., Nadim, F., Rahim, A., & Guttormsen, T. R. (2007). Statistical description of characteristic soil properties. In Offshore Technology Conference.
Uzielli, M., Lacasse, S., Nadim, F., & Phoon K.-K. (2006). Soil variability analysis for geotechnical practice. In Proceedings of the 2nd International Workshop on Characterisation and Engineering Properties of Natural Soils, Singapore.
Orchant, C. J., Kulhawy, F. H., & Trautmann, C. H. (1988). Critical evaluation of in-situ test methods and their variability. Report EL-5507(2), Palo Alto.
Yildiz, A., Karstunen, M., & Krenn, H. (2009). Effect of Anisotropy and Destructuration on Behavior of Haarajoki Test Embankment. International Journal of Geomechanics, 9, 153–168.
Ojala, A. E. K., Ikävalko, O., Palmu, J.-P., Vanhala, H., et al. (2007). Espoon Suurpellon alueen maaperän ominaispiirteet. Report, Geological Survey of Finland, Espoo.
Pätsi, K. (2009). Suurpellon syvästabiloidun koepenkereen analysointi. Master thesis, Helsinki University of Technology, Espoo.
Koskinen, M. (2014). Plastic anisotropy and destructuration of soft Finnish clays. Doctoral dissertation, Aalto University, Espoo.
Löfman, M. S., & Korkiala-Tanttu, L. K. (2019). Variability and typical value distributions of compressibility properties of fine-grained sediments in Finland. In Proceedings of the 7th International Symposium on Geotechnical Safety and Risk (ISGSR 2019).
Sällfors, G. (1975). Preconsolidation pressure of soft, high-plastic clays. Doctoral dissertation, Chalmers University of Technology.
Larsson, R., Bengtsson, P.-E., & Eriksson, L. (1997). Prediction of settlements of embankments on soft, fine-grained soils. In Calculation of settlements and their course with time. Information 13E, Swedish Geotechnical Institute.
Shapiro, S. S., & Wilk, M. B. (1965). An analysis of variance test for normality (complete samples). Biometrika, 52, 591–611.
Thode, H. C. (2002). Testing for normality. New York: Marcel Dekker.
Lacasse, S., & Nadim, F. (1996). Uncertainties in characterising soil properties. In Uncertainty in the geologic environment: from theory to practice. New York: ASCE.
Knuuti, M., & Länsivaara, T. (In press). Measurement uncertainty of the fall cone (FC) test. In Proceedings of the 18th Nordic Geotechnical Meeting, 2021, Helsinki.
Kelley, K. (2007). Sample size planning for the coefficient of variation from the accuracy in parameter estimation approach. Behavior Research Methods, 39, 755–766.
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This study was funded by the Finnish Transport Infrastructure Agency.
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Löfman, M.S., Korkiala-Tanttu, L.K. (2021). Inherent Variability of Geotechnical Properties for Finnish Clay Soils. In: Matos, J.C., et al. 18th International Probabilistic Workshop. IPW 2021. Lecture Notes in Civil Engineering, vol 153. Springer, Cham. https://doi.org/10.1007/978-3-030-73616-3_32
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