Geotechnical Investigation of the Slope Instability in the Gündoğan Village Settlement Area (Ardeşen-Rize)

Abstract

In the scope of this study, the slope stability problem in the Gündoğan (Ardeşen-Rize) village settlement area covering approximately 2.24 hectares was investigated by means of geotechnical way. The studies were performed in three stages as field, laboratory works and slope stability analyses. For this purpose, along the three survey lines; six boreholes with a total of 150 meters in length were drilled, geophysical studies were performed along the three lines and inclinometer measurements were taken in two boreholes. At the end of the field work, it was determined that the talus whose thickness varies between 5.0 and 16.5 meters overlies the parent material that was formed by the Late Cretaceous-aged Çağlayan Formation consisting of volcano-sedimentary rocks. To determine the physico-mechanical properties of the talus, undisturbed samples were taken from boreholes. Limit equilibrium and the Finite Element based Shear Strength Reduction (FEM-SSR) methods were used to perform stability analyses using the obtained data from field and laboratory studies and the results were compared. When examining the distribution of the failure surfaces obtained from the stability analyses, it was detected that the failure may continue as retrogressive type if there is not any precaution taken on the slope. Performed inclinometer measurements and stability analyses showed that the talus in the Gündoğan village settlement area is unstable and has a landslide potential.

Keywords

• Stability Analysis,FEM-SSR Method,Limit Equilibrium Method,Factor of Safety,Inclinometer Measurements

Gündoğan (Ardeşen-Rize) Köyü Yerleşim Alanındaki Yamaç Duraysızlığının Jeoteknik Açıdan İncelenmesi

Abstract

Bu çalışma kapsamında Gündoğan (Ardeşen-Rize) Köyü yerleşim alanının üstünde bulunduğu yamaçta meydana gelen ve yaklaşık olarak 2.24 hektarlık bir alanı kapsayan duraysızlık problemi jeoteknik açıdan incelenmiştir. Yapılan çalışmalar sırasıyla arazi, laboratuvar ve şev duraylılık analizi çalışmaları olmak üzere üç aşamada yürütülmüştür. Bu amaçla eğim yönünde 3 hat boyunca toplam 150 m derinliğinde 6 adet sondaj kuyusu açılmış, 3 profilde jeofizik çalışmalar gerçekleştirilmiş ve 2 sondaj kuyusunda inklinometre ölçümleri yapılmıştır. Arazi çalışmaları sonucunda ana kayayı Geç Kretase yaşlı Çağlayan Formasyonu’na ait volkano-tortul kayaçların oluşturduğu ve bu birimlerin üzerine kalınlığı 5.0-16.5 m arasında değişen yamaç molozunun geldiği belirlenmiştir. Yamaç molozunun fiziko-mekanik özelliklerini tespit etmek için araştırma sondajlarından örselenmemiş örnekler alınmıştır. Arazi ve laboratuvar çalışmalarından elde edilen veriler yardımıyla Limit Denge ve sonlu elemanlar tabanlı Kayma Dayanımı Azaltma Yaklaşımı (FEM-SSR) yöntemleri kullanılarak duraylılık analizleri yapılmış ve sonuçlar karşılaştırılmıştır. Duraylılık analizleriyle belirlenen kayma yüzeylerinin dağılımları incelendiğinde yamaçta önlem alınmaması durumunda yenilmenin gerileyen şekilde devam edebileceği saptanmıştır. Yapılan inklinometre ölçümleri ve duraylılık analizleri, Gündoğan Köyü yerleşim alanındaki yamaç molozunun duraysız olduğunu ve heyelan potansiyeli taşıdığını göstermektedir.

Keywords

• Duraylılık Analizi,FEM-SSR Yöntemi,Limit Denge Yöntemi,Güvenlik Sayısı,İnklinometre Ölçümleri

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