Doymamış Koşullardaki Bir Şevin Yağış Etkisindeki Duraylılığını Etkileyen Parametrelerin İncelenmesi

Çalışma kapsamında, yağışlı mevsimlerde şev duraysızlıklarının sıklıkla görüldüğü bir bölgede, doygun olmayan koşullardaki şevin duraylılığını etkileyen parametreler incelenmiştir. İncelenen parametreler; yağış yoğunluğu, yağış süresi, hidrolik iletkenlik ve şev eğimi olup; çalışmada bölgeye ait gerçek yağış verilerini de içeren bir veri aralığı kullanılarak, yarı-parametrik çalışma yapılmıştır. Bu şekilde şevin mevcut durumu ve parametre değişiminin etkisi aynı anda incelenebilmiştir. Yağışın etkisiyle oluşan emme basınçlarındaki değişim nümerik yöntemle elde edilmiştir. Şev analizlerinde negatif boşluk suyu basıncındaki değişim dikkate alınarak, Bishop limit denge yöntemi kullanılmıştır. Analizler sonucunda belirli bir yüksekliğin üzerindeki şevlerde yağışlı dönemde görülen göçmelerin nedeni ve incelenen parametrelerin duraylılığa etkisi gösterilmiştir.

Anahtar Kelimeler:

Doygun Olmayan Zeminler, Şev Duraylılığı, Sızma

Investigation of the Parameters Affecting the Stability of Unsaturated Soil Slope Subjected to Rainfall

In this study, impacts of some parameters on stability of unsaturated soil slope were invesitgated in a region, where slope instabilities were frequently observed during rainy seasons. The investigated parameters are rainfall (density and duration), hydraulic conductivity and incline of slope. A semi-parametric study was performed using a data range including the actual rainfall data and soil properties of the region. In this way, the current slope stability and effects of parameters could be examined at the same time. The change in suction pressures due to rainfall was obtained by numerical method. Limit equilibrium method was used to analyze slope stability and considering decrease in shear strength of soil due to change in pore water pressure. As a result of the analyses, the effects of parameters on slope stability and reasons of slope instabilities during rainy period were shown.

Keywords:

Rain Infiltration, Slope Stability, Unsaturated Soil,

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