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Studying Effect of Saturation Degree on the Bearing Capacity and Failure Mechanism of Sandy Soils

Sanaa Khalil

Department of Geotechnical Engineering, College of Civil Engineering, Damascus University, Damascus, Syria.

Nazih Abboud

Department of Geotechnical Engineering, College of Civil Engineering, Damascus University, Damascus, Syria.

Firas Almoukdad

Department of Geotechnical Engineering, College of Civil Engineering, Damascus University, Damascus, Syria.

DOI: https://doi.org/10.61706/sccee120116

Keywords: Footing, Failure mechanism, Saturation degree, Sandy soil, Bearing capacity

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Abstract

In this research, an experimental method was adopted on samples of sandy soils from Tartous city and from Tadmur city, the aim is studying the effect of saturation degree on the bearing capacity of partially saturated sandy soil and the failure mechanism. To achieve the aim of the research, experiments were conducted to determine the basic physical properties of the soils, and a series of laboratory loading tests were conducted for a model footing atop sandy soil under various saturation degrees, matric suction was measured and soil water characteristic curves were determined using filter paper technique. The results were analysed and discussed, and the experimental work demonstrated that saturation degree had a clear effect on the bearing capacity, with the values of the increase ranging between [2.3 - 9.7] times the bearing capacity in the full saturation state, an empirical relationship was proposed to simulate the bearing capacity of partially saturated sandy soil based on the experimental results. The results also demonstrated that saturation degree had a clear effect on failure mechanism, and failure mode attributed to dense soils was observed in medium-dense soils at certain degrees of saturation for tested soils.

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