Investigation of encased granular columns with finite element method

Öz

Nowadays, reinforcement techniques applied with granular column applications are widely used in increasing soil bearing capacity, preventing liquefaction and providing stability. In this study, polyester encased granular columns and tire encased granular columns were tested under vertical loading without backfill. Deformation behavior and load bearing capacity of granular columns were investigated experimentally and numerically. In this research, the critical behavior of the encasement materials used to prevent the deterioration of column stability under vertical loading has been demonstrated and lower deformations were observed in tire encased columns than polyester encased columns. In other words, the waste tires provide the integrative structure of the backfill material and have played an important role in increasing bearing capacity. This application opens new usage areas for end of life tires in terms of recycling. As a result of the laboratory tests and numerical analyses that showed similar results with these experiments, the tire encased granular columns reached 6 to 12 times more bearing capacity than the polyester encased granular columns

Anahtar Kelimeler

• Granular column
• Encasement
• Finite element method
• Numerical analysis
• Waste tires

Sarmal malzemeli granüler kolonların sonlu elemanlar yöntemi ile incelenmesi

Öz

Granüler kolon uygulamaları, zemin taşıma kapasitesinin artırılmasında, sıvılaşmanın önlenmesinde ve stabilitenin sağlanmasında günümüzde yaygın kullanılan güçlendirme teknikleri arasında yer almaktadır. Bu çalışmada, polyester ve ömrünü tamamlamış atık araç lastikleri ile sargılanmış taş ve kum kolonların geridolgusuz ortamda düşey yükleme altındaki deformasyon davranışları ve yük taşıma kapasiteleri deneysel ve nümerik olarak incelenmiştir. Kolon stabiletisinin düşey yükleme altında bozulmasını engellemek amacıyla kullanılan sargılama materyallerinin göçme anındaki kritik davranışlarını ortaya koyan bu araştırmalar sonucunda, atıl halde bulunan araç lastikleri polyester sarmallı kolonlara göre daha düşük seviyelerde deformasyonlar göstermiştir. Diğer bir deyişle geridolgu malzemesinin bütüncül yapısını muhafaza etmek için kullanılan atık lastikler, taşıma kapasitesi artışında önemli bir rol oynamıştır. Bu uygulama, aynı zamanda geri kazanım açısından ömrünü tamamlamış lastiklere yeni bir kullanım alanı açmaktadır. Yapılan laboratuvar deneyleri ve bu deneyler ile benzer sonuçlar ortaya koyan analizler sonucunda, lastik sarmallı kolonlar, polyester sarmallı kolonlara göre 6 ile 12 kat arasında daha yüksek taşıma kapasitesine ulaşmışlardır.

Anahtar Kelimeler

• Atık lastikler
• Granüler kolon
• Nümerik analiz
• Sarmal takviyesi
• Sonlu elemanlar yöntemi

Kaynakça

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