Derin Kazıların Olasılıksal Analizi Üzerinde Düşey Konumsal Değişkenliğin Etkisi: Bir Vaka Çalışması

Yıl 2023, Cilt: 26 Sayı: 3, 1233 - 1242, 01.10.2023

Dursun Enes Korkut Sami Oğuzhan Akbaş

https://doi.org/10.2339/politeknik.1324358

Öz

Bu çalışmada, derin kazıların olasılıksal analizinde kilin efektif içsel sürtünme açısının düşey konumsal değişkenliğinin dahil edilmesinin etkisi araştırılmaktadır. Önerilen metodoloji, Türkiye'nin Ankara ilinde bulunan enstrümantasyonlu bir derin kazı projesinin rastgele sonlu eleman modellemesi (RFEM) kullanılarak örneklendirilmiş ve doğrulanmıştır. Kazı, 20 metre derinliğe sahiptir ve altı seviyede öngermeli zemin ankrajları ile desteklenmektedir. Kilin efektif içsel sürtünme açısının düşey konumsal değişkenliğini benzeştirmek için rastgele alan teorisi ve Monte Carlo simülasyonu kullanılmıştır. Benzeştirme ile üretilen parametreler daha sonra Python yazılım dili aracılığıyla sonlu eleman modeline yerleştirilerek, fore kazık iksa yapısında yanal deformasyonlar ve eğilme momentlerinin olasılıksal dağılımı incelenmiştir. Monte Carlo simülasyonlarından elde edilen sonuçlar, konumsal değişkenliğin göz önünde bulundurulmasının ve değerinin ortaya çıkan yanal deformasyonlar, eğilme momentleri ve sistem yenilme olasılığı üzerinde etkisinin olduğunu göstermektedir.

Anahtar Kelimeler

Monte Carlo Simulasyonu, Rasgele Alan Teorisi, Sonlu Elemanlar Yöntemi

The Effect of Incorporating Vertical Spatial Variability on the Probabilistic Analysis of a Deep Excavation: A Case Study

Öz

This study explores the impact of including the vertical spatial variability in effective stress friction angle of clay on the probabilistic analysis of deep excavations. The proposed methodology is demonstrated and verified by conducting random finite element modeling (RFEM) of an instrumented deep excavation project situated in Ankara, Turkey. The excavation has a depth of 20 meters and is supported by six levels of pre-stressed ground anchors. To simulate the vertical spatial variability of effective stress friction angle in the clay, Monte Carlo simulation method and the random field theory are employed. The simulated parameters are then inserted into the finite element model via Python programming language to analyze the probabilistic distribution of lateral deflections and bending moments in the drilled shaft wall. The results obtained from the Monte Carlo simulations reveal that the incorporation and selected value of spatial variability significantly impacts the resulting lateral movements, bending moments, and the probability of failure of the system.

Anahtar Kelimeler

Monte Carlo Simulation, Random Field Theory, Finite Element Method

Kaynakça

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