Plastik olmayan bir silt zemin üzerinde yapılan çevrimsel üç eksenli deneyler sırasında oluşan aşırı boşluk suyu basıncının değerlendirilmesi
Çevrimsel yükleme, boşluk suyu basınçlarında artışlar meydana getirerek, daha sonra sıvılaşma ve oturmalara yol açabilmektedir. Yakın zamanda yapılan çalışmalarda, boşluk suyu basıncının ilksel çevre basıncına eşit olması durumunda, çevrimsel gerilme oranı ve zeminin izafi sıkılığının aşırı boşluk suyu basıncının gelişiminde büyük rolü olduğu vurgulanmaktadır. Bununla birlikte, boşluk suyu basıncı aynı zamanda eksenel deformasyonun bir fonksiyonudur. Bu bağlamda, plastik olmayan bir silt zeminin boşluk suyu basıncı gelişim davranışının değerlendirilebilmesi için bir dizi çevrimsel üç eksenli basınç deneyi yapılmıştır. Deneyler ile, boşluk suyu basıncı, çift genlikli eksenel deformayon ve çevrim sayısının çevrimsel gerilme oranına bağımlılığı araştırılmıştır. Bu amaçla, suya doygun örnekler üzerinde gerilme kontrollü çevrimsel üç eksenli basınç deneyleri 0.1 Hz frekansta ve 100 kPa çevre basıncında tatbik edilmiştir. Sıvılaşmaya neden olan çevrim sayısının, artan çevrimsel gerilme oranı ve izafi sıkılık ile azaldığı elde olunmuştur. Çalışmada elde edilen veriler, plastik olmayan silt zeminin boşluk suyu basıncı gelişim davranışıbı detaylarlandırmaktadır ve pratik amaçlarla kullanılabilir.
Anahtar Kelimeler:
Dinamik üç eksenli deneyler, plastik olmayan silt, aşırı boşluk suyu basıncı
Evaluation of Excess Pore Water Pressure Build-up During Cyclic Triaxial Tests on a Non-plastic Silt
Cyclic loading is responsible for pore water pressure buildup, which may later cause liquefaction and surface settlements. Recent studies emphasize that as the pore water pressure equalizes to initial confining stress, cyclic stress ratio and relative density of soil play a great role in buildup of excess pore water pressure. Nonetheless, pore water pressure is also a function of axial strain. In this regard, cyclic triaxial tests were carried out to evaluate the pore water pressure buildup behavior of a nonplastic silt. It was aimed to determine the dependence of pore water pressure, double amplitude of axial strain and number of cycles on cyclic stress ratio. In this scope, stress-controlled cyclic triaxial tests at a loading frequency and confining pressure of 0.1 Hz and 100 kPa were carried out on saturated samples. It was understood that number of loading cycles leading to liquefaction were decreased by increases in cyclic stress ratio and relative density. The data obtained in this study, bringing an insight into pore water pressure build-up behavior of nonplastic silts, can be used for practical purposes.
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- Yayın Aralığı: Yılda 4 Sayı
- Başlangıç: 2013
- Yayıncı: Düzce Üniversitesi Fen Bilimleri Enstitüsü