Derin Kazı Analizlerinde Küçük Şekil Değiştirme Rijitliğinin Etkisi

Zemin-yapı etkileşiminde derin kazı destek sistemlerinin davranışı son yıllarda pek çok araştırmacı tarafından çalışılmaktadır. Ancak zeminin küçük şekil değiştirme rijitliğini dikkate alan çalışmalar çok fazla bulunmamaktadır. Bu durumun sebebi olarak bu etkiyi değerlendiren sonlu elemanlar programlarının yeterli sayıda bulunmayışı söylenebilir. Bu çalışma kapsamında geoteknik problemlerin çözümünde sıkça kullanılan bir sonlu elemanlar programı olan Plaxis yazılımı ile analizler gerçekleştirilmiştir. Programın kütüphanesinde birçok zemin modeli bulunmaktadır. Bunlar arasında sıkça kullanılan Pekleşen Zemin Modeli (Hardening Soil Model) ve bu modelin küçük şekil değiştirme rijitliği etkilerini dikkate alan Pekleşen Zemin Küçük Birim Deformasyon Modeli (Hardening Soil Small Strain Model) bu çalışmada kullanılmıştır. Bu modeller ile üç adet vakanın analizleri gerçekleştirilmiştir. Analiz sonuçları inklinometre ölçümleri ile karşılaştırılmıştır. Çalışma sonucunda model analiz sonuçları ile yerinde alınan ölçümler karşılaştırmalı olarak sunulmuştur. HS_ss modelin HS modele göre saha ölçümlerine daha yakın olduğu görülmüştür.

Anahtar Kelimeler:

Derin Kazılar, Pekleşen Zemin Modeli, Pekleşen Zemin Küçük Birim Deformasyon Model

The Effect of Small Strain Stiffness in Deep Excavation Analyzes

The behavior of deep excavation support systems at soil-structure interaction has been studied by many researchers in recent years. However, studies that considering the rigidity of the small strain of the soil are not very common. For this situation, it can be said that there is not enough number of finite element programs evaluating this effect. Within the scope of this study, analyzes were performed by Plaxis software, is a finite element program, is frequently used to solve geotechnical problems. There are many soil models in the library of the program. Among these, Hardening Soil Model (HS), which is frequently used, and Hardening Soil Small Strain Model (HS_ss), which takes into account the effects of small strain stiffness of this model, were used in this study. Three cases were analyzed with these models. The analysis results were compared with the inlinometer measurements. As a result of the study, model analysis results and in situ measurements are presented comparatively. The HS_ss model was found to be closer to the field measurements than the HS model.

Keywords:

Deep Excavation, Hardening Soil Model, Hardening Soil Small Strain Model,

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