Ali Fırat ÇABALAR, Zuheir KARABASH, Süleyman DEMİR

Narlı Kumunun Üç Eksenli Kayma Davranışı

Bu çalışmada, Güneydoğu Anadolu Bölgesi’nin batısındaki altyapı inşaat faaliyetlerinde sıklıkla kullanılan Narlı Kumuna ait kayma davranışını araştırmak için yapılan üç eksenli basınç deneyi sonuçları sunulmaktadır. Üç farklı efektif gerilme (50 kPa, 100 kPa, ve 150 kPa) ve iki farklı konsolidasyon süresinin (3 saat, ve 18 saat) kayma davranışına etkisi konsolidasyonlu-drenajlı (CD) ve konsolidasyonludrenajsız (CU) deneylerle araştırılmıştır. Çalışmada, Narlı Kumuna ait üç farklı rölatif sıkılıktaki (gevşek, orta sıkı, sıkı) kayma davranışı da sunulmaktadır. Araştırmacılar ve arazide çalışan mühendislerin kullanımı için sunulan deney sonuçları, Narlı Kumuna ait kayma mukavemeti ve rijitlik değerlerinin efektif gerilme, konsolidasyon süresi, ve rölatif sıkılık değerlerindeki artışa bağlı olarak arttığını göstermiştir. Ayrıca, CD şartları altında test edilen örneklere ait deviatörik gerilme, rijitlik, ve içsel sürtünme açısı değerlerinin CU şartlarında test edilen aynı numunelere göre daha yüksek olduğu gözlemlenmiştir.

Anahtar Kelimeler:

Narlı kumu, Üç eksenli test, Rölatif sıkılık, Konsolidasyon süresi

Triaxial Shear Behavior of Narlı Sand

This study presents an intensive series of conventional triaxial compression tests conducted to investigate the shear behavior of Narli sand, which is a widely consumed geomaterial in earthwork projects in the southern central of Turkey. The effect of three different effective confining pressures (50 kPa, 100 kPa, and 150 kPa) and two consolidation periods (3 hrs, 18 hrs) were investigated during the both consolidated drained (CD) and consolidated undrained (CU) tests. The study also presents the effect of different relative densities (loose, medium, and dense state of the sand) to the shear response of Narli sand. Test results, which are presented for further use by researchers and engineers in practice, indicated that the shear strength and stiffness of Narli sand increase as the effective confining pressure, consolidation period, and the relative density values increase. Further, Narli sand tested in the CD condition exhibits deviatoric stress, stiffness, angle of internal friction values higher than their values observed in the CU condition.

Keywords:

Narli sand, Triaxial test, Relative density, Consolidation period,

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