Depolanmış Tarama Çamurlarının Sıkışabilirlik ve Mukavemet Davranışının Laboratuvar ve Arazi Deneyleri ile İncelenmesi

Öz

Bu çalışmada, Haliç tarama çamurunun karada depolanması durumunda, kendi ağırlığı altında ve sürşarj yükleri etkisindeki sıkışabilirlik ve mukavemet davranışı incelenmiştir. Bu amaçla, taranan çamurun karada depolanması durumunda kendi ağırlığı altında konsolidasyon davranışını incelemek için laboratuvarda dört adet büyük boyutlu model deney ve bir adet küçük boyutlu sedimantasyon deneyi gerçekleştirilmiştir. Bu deneylerde kendi ağırlığı altında konsolidasyondan sonra alınan örselenmemiş numuneler üzerinde yapılan ödometre deneyleri ile sürşarj yükleri etkisindeki sıkışabilirlik ve model deneylerde yapılan veyn deneyi ile derinlik boyunca drenajsız kayma mukavemeti ölçülmüştür. Zeminin kendi ağırlığı altındaki konsolidasyon davranışını incelemek için gerçekleştirilen model deneyler ve sedimentasyon deneyinden ölçülen oturma değerlerinden konsolidasyon katsayısı cv’nin 0.91-10.72 m2/yıl aralığında ve drenajsız kayma mukavemetinin de 4-20 kPa arasında değiştiği belirlenmiştir. Tarama çamurunun karada depolanmasından 13 yıl sonra yapılan arazi deneylerinden belirlenen drenajsız kayma mukavemeti (SPT N darbe sayısına bağlı olarak ve UU deneylerinden) benzer şekilde cu=4-20 kPa arasında değişim göstermiştir. Haliç’ten taranan ve eski taş ocağında depolanan yaklaşık 25 m kalınlıktaki tarama çamurunun düşük taşıma gücüne ve yüksek sıkışabilirliğe sahip olduğu tespit edilmiştir.

Anahtar Kelimeler

• Kendi ağırlığı altında konsolidasyon
• sürşarj yükleri
• tarama çamuru
• kayma mukavemeti
• sıkışabilirlik

Investigation of Compresibility and Strength Behaviour of Deposited Dredged Slurries by Laboratory and Field Tests

Öz

In this study, the consolidation and the strength behavior of Haliç dredged slurry stored at a disposal site were investigated through laboratory and field tests. For this purpose, four large scale model tests and a sedimentation test were carried out in the laboratory in order to simulate the consolidation process of the dredged material under self weight conditions. In these tests in order to investigate the compressibility behaviour, consolidation tests were carried out on the undisturbed samples recovered from the sedimentation tests. Additionally, vane test were performed in the large scale model tests to determine the undrained shear strength variation with depth. The coefficient of consolidation (cv) values obtained from the settlements measured in model tests and undrained shear strength values measured from vane tests were determined to be 0.91 – 10.72 m2/year and 4-20 kPa, respectively. The undrained shear strength values determined from the field tests carried out at the site 13 years after the storage of dredged slurry were determined to be 4-20 kPa based on SPT-N tests and UU tests. As a result of the field tests performed at the disposal site, it is determined that 25m thick dredged material deposited at the site has low bearing capacity and high compressibility characterisctics

Anahtar Kelimeler

• Self weight consolidation
• surcharge loads
• dredged sludge
• shear strength
• compressibility

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