Doymamış Koşullardaki Bir Şevin Yağış Etkisindeki Duraylılığını Etkileyen Parametrelerin İncelenmesi

Yıl 2019, Cilt: 30 Sayı: 5, 9483 - 9506, 01.09.2019

Taha Taşkıran Ayşenur Aslan Fidan

https://doi.org/10.18400/tekderg.399877

Öz

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

Öz

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.

Anahtar Kelimeler

Rain Infiltration, Slope Stability, Unsaturated Soil

Kaynakça

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