Silt Kum Karışımlarının Sıvılaşma Davranışı ve Sıvılaşma Sonrası Hacimsel Deformasyon Özellikleri

Abstract

Sunulan çalışmada, silt kum karışımlarının sıvılaşma davranışları ve sıvılaşma sonrası hacimsel deformasyon özellikleri araştırılmıştır. Çalışma, İzmir Bayraklı bölgesinden temel kazısı sırasında elde edilen silt kum karışımı ile gerçekleştirilmiştir. Yapılan çalışmada silt içeriğinin sıvılaşma dayanımına etkisinin araştırılması için 8 farklı ince tane içeriğinde (FC=%0, 5, 10, 20, 40, 60, 80,100) dinamik üç eksenli deney aleti ile JGS 0542-2000 standardına uygun olarak drenajsız deneyler gerçekleştirilmiş ve deneyler sonucunda hacimsel deformasyon özelliklerinin belirlenmesi için drenaj vanaları açılarak çıkan su miktarları büret yardımıyla ölçülmüştür. Sıvılaşma deneyleri rölatif sıkılık yerine, artan silt içerikleri ile birlikte kaba daneler ve ince daneler arası boşluk oranı kavramlarına göre sıvılaşma kriterleri belirlenmiştir. Ayrıca bu durumda sıvılaşma dayanımında eşik silt içeriği bulunmuştur. Sıvılaşma sonrası hacimsel deformasyon davranışları ise silt içeriğine bağlı olarak yorumlanmıştır.

Keywords

• Silt kum karışımı,sıvılaşma,hacimsel deformasyon,kaba - ince daneler arası boşluk oranı

Liquefaction Behavior of Silt Sand Mixtures and Post Liquefaction Volumetric Strain Properties

Abstract

In this study, the liquefaction behavior silty sand mixtures and volumetric deformation properties were investigated. The study was implemented on samples of silt sand mixtures obtained during an excavation at Bayraklı, Izmir, Turkey. In order to investigate the liquefaction behavior of silty sand, undrained cyclic triaxial compression tests were carried out according to JGS 0542-2000, for 8 different fines contents (0, 5, 10, 20, 40, 60, 80, 100%). To determine the volumetric deformation properties, the water content change was measured by allowing drainage into a burette upon completion of a cyclic test. The liquefaction criteria was determined by using intergranular-interfine void ratios. A threshold fines content to serve as liquefaction criterion has also been determined. The volumetric deformation properties behavior were reviewed depending on the silt content.

Keywords

• Silt Sand Mixtures,Liquefaction,Volumetric Strain,intergranular - interfine void ratios

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