Siltli Kumlarda Gerilme Kontrollü ve Deformasyon Kontrollü Sıvılaşma Testlerinin Karşılaştırılması

Öz

Deprem esnasında farklı tane çaplarında ve ince tane içeriğindeki siltli kumların sıvılaşma davranışı aynı olmayıp bu tür zeminlerin sıvılaşma mekanizmasını anlamak geoteknik deprem mühendisliğinin önemli konularından biri olmaya devam etmektedir. Bu amaçla, bu çalışmada iki farklı gradasyondaki 20/30 ve 30/50 kumlarına, %5 ve %30 oranında silt karıştırılarak hazırlanan siltli-kum numuneleri üzerinde, dinamik basit kesme test cihazı kullanılarak deformasyon kontrollü ve gerilme kontrollü testler gerçekleştirilmiştir. Sonuçlar deformasyon kontrollü ve gerilme kontrollü testlerin sonuçları arasında anlamlı bir fark olmadığını göstermiştir. Ancak silt içeriğinin artışı ile hem 20/30 kumu ve hem de 30/50 kumuna ait siltli-kum numunelerinin sıvılaşmaya karşı dirençleri azalmıştır. Ayrıca rölatif sıkılığın artışı ile tüm numunelerin sıvılaşmaya karşı direnci artmıştır.

Anahtar Kelimeler

• Sıvılaşma,Kum,Silt

Comparison of Stress Control and Deformation Controlled Liquefaction Tests in Silty Sands

Öz

The liquefaction behavior of silty sands with different grain diameters and fine grain content during the earthquake is not the same and understanding the liquefaction mechanism of such soils continues to be one of the important subjects of geotechnical earthquake engineering. For this purpose, deformation controlled and stress-controlled tests were performed on silty-sand samples prepared by mixing 5% and 30% silt to 20/30 and 30/50 sands of two different grades using cyclic simple shear tester. The results showed that there was no significant difference between the results of deformation controlled and stress-controlled tests. However, with the increase of silt content, the resistance to liquefaction of silty-sand samples of both 20/30 sand and 30/50 sand decreased. In addition, the resistance to liquefaction of all samples increased with increasing relative density.

Anahtar Kelimeler

• Liquefaction,Sand,Silt,Cyclic Simple Shear Test

Kaynakça

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