A comparison between performances of the behavioral models in evaluating load-bearing capacity of piles in fine-grained unsaturated soil

Omid Bandehzadeh, Masoud Mirmohammad Sadeghi, Mohammad Ali Rowshanzamir, Alborz Hajian Nia


Virtually all structural piles are installed on the top of groundwater level, and these piles are located on unsaturated soils. In this case, the negative orifice water pressure caused by capillarity significantly influences the mechanical behavior of unsaturated soils. Consequently, structural suction is highly important to load-bearing capacity of loads. In this paper, an evaluation was drawn between the Mohr-Coulomb, modified Cam-Clay, and Barcelona behavioral models using the finite-difference method, and results of studies conducted to estimate load-bearing capacity in the static state were provided. The behavioral model guidelines matched the laboratory models. To estimate soil vividness on the suction level of concern, the water-soil curve (showing suction patterns in relation to moisture) utilized. The general tendencies of settlement gotten by the numerical examination are reliable with pile insert test results. Results suggest that the Barcelona personality model (BBM) yields more realistic estimates of load capacity as it looks at the effect of unsaturated soil suction.


single pile; Unsaturated soil; Ultimate bearing capacity; Mohr–Coulomb; modified Cam-Clay; BBM; matric suction

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DOI: http://dx.doi.org/10.15421/2018_207

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