Investigation of the effect of stone column design parameters on consolidation

Yıl 2023, , 200 - 206, 15.01.2023

Firdevs Uysal , Abdulazim Yıldız

https://doi.org/10.28948/ngumuh.1118184

Öz

The stone column is an effective ground improvement method that is used to increase the load-bearing capacity of soft soil and speed up the process of soft soil consolidation and decrease the settlement of soil. In this study, a series of numerical studies have been performed to evaluate the time-dependent behavior of stone column by using a validated numerical model and model parameters from a past laboratory study in literature. The soft soil reinforced with a stone column was modeled with Plaxis 2D using the unit cell concept. Parametric studies were conducted to understand the impact of stress concentration ratio, permeability ratio, and diameter ratio on the time-dependent settlement behavior of stone column. The numerical results indicate that these design parameters have a significant influence on the acceleration of the consolidation and increasing the average consolidation rate.

Anahtar Kelimeler

Stone column, Soft soil, Consolidation, Numerical modeling, Unit cell

Taş kolon tasarım parametrelerinin konsolidasyona etkisinin araştırılması

Öz

Taş kolon, yumuşak zeminin taşıma kapasitesini artırmak, yumuşak zemin konsolidasyonunu hızlandırmak ve zemin oturmasını azaltmak için kullanılan etkili bir zemin iyileştirme yöntemidir. Bu çalışmada, literatürde geçmiş bir laboratuvar çalışmasından alınan doğrulanmış bir sayısal model ve model parametreleri kullanılarak taş kolonun zamana bağlı davranışını değerlendirmek için bir dizi sayısal çalışma yapılmıştır. Taş kolon ile iyileştirilmiş yumuşak zemin birim hücre yaklaşımı kullanılarak Plaxis 2D ile modellenmiştir. Gerilme konsantrasyon oranı, permeabilite oranı ve çap oranının taş kolonun zamana bağlı oturma davranışı üzerindeki etkisini anlamak için parametrik çalışmalar yapılmıştır. Sayısal sonuçlar, bu tasarım parametrelerinin konsolidasyonun hızlanması ve ortalama konsolidasyon hızının artması üzerinde önemli bir etkiye sahip olduğunu göstermektedir.

Anahtar Kelimeler

Taş kolon, Yumuşak zemin, Sayısal modelleme, Birim hücre, konsolidasyon

Kaynakça

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