Abstract
Rainfall-induced landslides are among the most common natural hazards in many countries. Especially in unsaturated soils, rainfall is one of the basic causes of slope failure. This stems from the suction zone, where the negative pore-water pressure occurs in unsaturated soils. This zone causes an increase in the shear strength of the soil. After rainfall events, infiltration of the rain causes reduction of the suction and increase groundwater level. Then, the pore water pressure becomes positive and slope failures occur in unsaturated soils. This study examines the slope failure occured due to rainfall intensity and duration threshold on the unsaturated soil slopes in the Ankara province of Turkey. Stability analyses of unsaturated soil under the effect of rainfall infiltration were performed using Seep/W and Slope/W modules of the Geostudio software suite. The study shows that the matric suction pressure is an important parameter that must be considered for stability analyses. The study reveals that there is a non-linear relationship between rainfall infiltration and the factor of safety. Besides, it was determined that the changes in pore water pressure and infiltration significantly affect the safety factor of safety.
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Finally, I would like to thank Hendese Co. Ltd. for their contributions to the field works.
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Erdağ, A., Sinan Işık, N. Effect of rainfall ıntensity on the stability of unsaturated slopes of silty clay soils of Kazan, Ankara, Turkey. Arab J Geosci 15, 894 (2022). https://doi.org/10.1007/s12517-022-10174-7
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DOI: https://doi.org/10.1007/s12517-022-10174-7