STABILITY ANALYSIS OF STONE COLUMN SLOPES UNDER DIFFERENT EARTHQUAKE LOADS

Öz

How a slope behaves under the action of a dynamic load such as an earthquake is of great importance in stability analyses of slopes. Improving the region where slope failure occurs or preventing potential slope failure can lead to reducing the factors that excite movement in a slope and/or increasing the sliding resistance of the soils. In this study, the stone column method was used as an improvement technique. In the analysis performed with Plaxis 2D, safety factors were defined for slopes with different slope angles, soil cohesion, and three different earthquake magnitudes. Later, the slopes with the same characteristics were improved using the stone column method. The slopes were improved with different s/D ratios and different internal friction angles of the stone column. The same earthquake forces were also applied to the improved slopes and the factors of safety were determined.

In the study, slope models with stone columns designed without the effect of earthquake force showed an increase in safety values in the range of 1.01to 1.34 times compared to slope models without stone columns. It was found that the safety values of the slope models with stone columns increased by 1.02-1.80 times compared to the slope models without stone columns under the effect of earthquake force

Anahtar Kelimeler

• Acceleration
• Earthquake forces
• Slope stability
• Stone columns
• Finite Element Analysis

Farklı Deprem Kuvvetleri Altında Taş Kolonlu Şevlerin Stabilite Analizi

Öz

Bir şevin deprem gibi dinamik bir yükün etkisi altında nasıl tepki verdiği, şevlerin duraylılık analizlerinde çok önemlidir. Bir şev göçmenin meydana geldiği bölgeyi iyileştirmek veya olası bir şev göçmesini önlemek, bir şevde hareketi teşvik eden faktörlerin azalmasına ve/veya zeminlerin kayma direncinin artmasına sağlar. Bu çalışmada iyileştirme tekniği olarak Taş Kolon yöntemi kullanılmıştır. Plaxis 2D ile yapılan analizde, farklı şev açıları, zemin kohezyonu ve üç farklı deprem kuvveti ile modellenen şevlerin güvenlik faktörleri belirlenmiştir. Daha sonra aynı özelliklere sahip şevler taş kolon yöntemi ile iyileştirilmiştir. Eğimler, farklı s/D oranları ve farklı taş kolon iç sürtünme açıları kullanılarak iyileştirilmiştir. Aynı deprem kuvvetleri iyileştirilmiş şevlere de uygulanmış ve güvenlik faktörleri bulunmuştur.
Çalışmada, deprem kuvvetinin etkisi olmadan tasarlanan taş kolonlu şev modelleri, taş kolonsuz şev modellerine göre güvenlik değerlerinde 1.01-1.34 kat arasında bir artış göstermiştir. Taş kolonlu şev modellerinin güvenlik değerlerinin, deprem kuvvetinin etkisi altında taş kolonsuz şev modellerine göre 1,02-1,80 arttığı görülmüştür.

Anahtar Kelimeler

• İvme
• Deprem kuvvetleri
• Şev stabilitesi
• Taş kolonlar
• Sonlu Elemanlar Analizi

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