Relationship between Shearband Thickness and Relative Density for Cohesionless Soil

Abstract

In this study, shear band thickness was examined by performing shear box tests on coarse-grained soil. The dimensions of the standard shear box experiment device were modified to be 15 cm x 15 cm x 9 cm. Additionally, the shear band thickness was observed throughout the entire shear phase by using a transparent plate on one surface of the shear box test device. The experiments were carried out at 30%-50%-80% relative densities and under a constant 54 kPa normal stress. The experiments were recorded with a high-resolution camera and the shear band thickness was determined by image processing method. By using geotextile in the experiments, reinforced and unreinforced conditions were compared. In the experiments carried out without using geotextile, the shear band thicknesses were found to be 27.1 mm, 26.7 mm and 25.2 mm for 30%, 50% and 80% tightness conditions, respectively. With the inclusion of geotextile in the interface, the shear band thicknesses were determined as 25.9 mm, 23.2 mm and 20.2 mm for 30%, 50% and 80% thicknesses, respectively. It was determined that shear band thicknesses decreased with the use of geotextile and shear band formation was not observed under the geotextile.

Keywords

• Shearband
• Coarse Grain
• Shear
• İmage Processing

Kohezyonsuz Zeminlerde Kesme Bant Kalınlığı ve Rölatif Sıkılık Arasındaki İlişki

Abstract

Bu çalışmada iri daneli zemin üzerinde, kesme kutusu deneyleri yapılarak kesme bant kalınlığı incelenmiştir. Standart kesme kutusu deneyi cihazının boyutları 15 cm x 15 cm x 9 cm olacak şekilde modifiye edilmiştir. Ayrıca, kesme kutusu deney cihazının bir yüzeyinde şeffaf plaka kullanılarak kesmebant kalınlığı bütün kesme aşaması süresince gözlemlenmiştir. Deneyler %30-%50-%80 sıkılık oranlarında ve sabit 54 kPa normal gerilme altında yapılmıştır. Deneyler yüksek çözünürlüklü kamerayla kayıt altına alınarak görüntü işleme yöntemiyle kesme bant kalınlığı belirlenmiştir. Deneylerde geotekstil kullanılarak, zemin-zemin ve zemin-geotekstil ara yüzey kesme durumlarında ortaya çıkan kesme bantları karşılaştırılmıştır. Geotekstil kullanılmadan gerçekleştirilen deneylerde %30, %50 ve %80 sıkılık durumları için sırasıyla kesme bant kalınlıkları 27.1 mm, 26.7 mm ve 25.2 mm bulunmuştur. Geotekstil in ara-yüzeye dahil edilmesiyle birlikte ise sırasıyla %30, %50 ve %80 kalınlıklar için kesme bant kalınlıkları 25.9 mm, 23.2 mm ve 20.2 mm olarak belirlenmiştir. Geotekstil kullanımı ile kesme bant kalınlıklarının azaldığı ve kesme bant oluşumunun geotekstil altında görülmediği belirlenmiştir

Keywords

• Kesme bant
• Rölatif Sıkılık
• Görüntü İşleme
• Kesme

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