Mustafa VEKLİ, Mustafa AYTEKİN, Sabriye Banu İKİZLER, Ümit ÇALIK

Taş kolonla iyileştirilmiş şeylerin stabilite analiz

Bu çalışmada, taş kolonla iyileştirilmiş evlerin stabilitesi deneysel olarak ve sonlu elemanlar yöntemi kullanılarak incelenmiştir. Deneyler, dikdörtgen kesitli küçük ölçekli bir kutu içerisine yerleştirilen evli yumuşak kil ile yapılmıştır. evli yumuşak kilin üstüne konulan bir temelin sınır taşıma gücü ve evin kaymaya karşı güvenlik sayıları bulunmuştur. Sayısal çalışmada kil ve çakıl iki boyutlu düzlem deformasyon koşullarında Mohr-Coulomb malzeme modeliyle temsil edilmiştir. Yapılan deneysel ve sayısal çalışmalardan elde edilen sonuçların uyum içinde olduğu görülmüştür. Bu uyumdan yola çıkarak, taş kolonların ev stabilitesine etkisinin araştırılması amacı ile bir ve iki tabakalı zemin kesitlerinin dikkate alındığı parametrik bir çalışma gerçekleştirilmiştir. Parametrik çalışmada analizler, farklı ev açıları, farklı c/( γ H) oranları ve farklı s/D (Taş kolonların merkezleri arası mesafe/ Taş kolon çapı) oranları için yapılmıştır. Analizler sonucunda taş kolonların evlerin stabilitesini 1.25~1.51 kat artırdığı gözlenmiştir.

Anahtar Kelimeler:

Taş kolon, stabilizasyon, şev stabilitesi, taşıma gücü, sonlu elemanlar modeli

Stability analysis of slopes treated by stone columns

In this study, stability of slopes that treated by stone columns has been investigated by experimentally using small scale laboratory model a s well as numerically using the finite element method. In the laboratory experiments, soft clay is placed in a small testing box that has a rectangular cross section. The soft clay has been g iven a sloped shape in the box. Ultimate bearing capacity of a footing that has been rested on upper side of the slope, and safety factor of the sloped soft clay against shear failure has been obs erved. Mohr-Coulomb material model has been employed for plane strain condition in the numerica l modeling of the soft clay. The results of experimental study and numerical model are compatib le. Since the results are compatible, one- layer and two-layer clay stratums are considered to investigate the effect of stone columns on the stability of slopes in hypothetical cases. In the h ypothetical cases, analyses have been performed for different angles of slopes, various ratios of c /( γ H) and s/D (distance between center of stone columns/diameter of stone columns). As a result of the study, it is concluded that the factor of safety is increased 1.25~1.51 times by stone columns.

Keywords:

Stone Column, soil improvement, slope stability, bearing capacity, finite element methods,

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