Kaolin Kili Içeren Kumların Boşluk Suyu Basinci Oluşumunun Değerlendirilmesi

Öz

Çalışmanın temel amacı, dinamik yükler altında killi kumun aşırı boşluk suyu basıncı gelişimini, literatürdeki üç farklı model kullanarak incelemektir. Bu amaçla, farklı çevrimsel gerilme genlik oranlarında aşırı boşluk suyu basıncı gelişimini elde edebilmek için üç farklı kaolin kil içeriğiyle (FC=5-15%) hazırlanan numuneler üzerinde gerilme kontrollü dinamik üç eksenli deneyler yapılmıştır. Deneyler, 100 kPa efektif çevre basıncı altında gerçekleştirilmiştir. Sonuçlar, drenajsız dinamik koşullar altında killi kumların aşırı boşluk suyu basıncı gelişimini elde etmek için kullanılmıştır. Ardından, elde edilen veriler, kaolin içeren kumlar için model katsayılarını güncellemek amacıyla üç farklı boşluk suyu basıncı üretim modeli ile karşılaştırılmıştır.

Anahtar Kelimeler

• Kaolin kili
• boşluk suyu basıncı oranı
• dinamik üç eksenli deney
• kötü derecelenmiş kum

Evaluation of Pore Water Pressure Generation in Sands Containing Kaolin Clay

Abstract

The main aim of this study is to investigate the excess pore water pressure development of clayey sand under dynamic loads using three different models from the literature. For this purpose, stress-controlled dynamic triaxial test were performed on specimens prepared with three different kaolin clay contents (FC=5-15) to measure excess pore water pressure generation at various cyclic stress amplitude ratios. The tests were conducted under an effective confining pressure of 100 kPa. The results were used to obtain excess pore water pressure development of clayey sands under undrained dynamic conditions. Then, the results were compared with three different pore water pressure generation models to update the model coefficients for sands containing kaolin.

Keywords

• kaolin clay
• pore pressure ratio
• cyclic triaxial test
• poorly graded sand

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