Uçucu Kül Bazlı Malzemelerle Güçlendirilen Killi Şevlerin Sayısal Analizi

Abstract

Bu çalışma, kilden oluşan şev dolgularının stabilitesini artırmak amacıyla, C sınıfı uçucu kül, F sınıfı uçucu kül ve alkali aktivatör ile aktive edilmiş F sınıfı uçucu kül kullanım potansiyelini, PLAXIS yazılımı ile gerçekleştirilen 3 boyutlu sayısal modelleme aracılığıyla incelemektedir. Sayısal analizlerde kullanılan geoteknik parametreler, yazar tarafından daha önce yürütülen laboratuvar deneylerinden elde edilmiştir. Elde edilen sonuçlar, alkali aktivatörle stabilize edilmiş F sınıfı uçucu külün, güvenlik katsayısında belirgin artışlar ve plastik şekil değiştirme bölgelerinde azalmalar sağlayarak en etkili iyileştirmeyi sağladığını ortaya koymaktadır. C sınıfı uçucu kül, zemin rijitliğini belirli ölçüde artırsa da deformasyonu azaltma konusunda tam anlamıyla etkili olamamıştır. F sınıfı uçucu kül ise düşük reaktivitesi nedeniyle kontrol numunesine benzer bir davranış sergilemiş; ancak alkali aktivasyon sonrası performansında önemli iyileşmeler gözlenmiştir. Bu bulgular, özellikle granüler dolgu malzemesinin kısıtlı olduğu bölgelerde, yerel kil zeminlerin alkali aktivatör ile işlenmiş uçucu kül kullanılarak etkin şekilde iyileştirilebileceğini göstermektedir. Bu yaklaşım, yalnızca şev performansını artırmakla kalmayıp, aynı zamanda doğal kaynak tüketimini azaltarak ve inşaat maliyetlerini düşürerek daha sürdürülebilir geoteknik uygulamalara katkı sağlamaktadır.

Keywords

• Şev Stabilitesi
• Plaxis 3D
• Uçucu Kül ile Zemin Iyileştirmesi
• Alkali Aktivasyon
• Kil

Numerical Investigation of Clayey Slopes Stabilised with Fly Ash-Based Materials

Abstract

This study investigates the potential use of Class C fly ash, Class F fly ash, and alkali-activated Class F fly ash to improve the slope stability of clay embankments through 3D numerical modelling with PLAXIS. Laboratory-based input parameters, derived from previous experimental work by the author, were used to define the geotechnical behaviour of the soils in the simulations. Results demonstrate that clay slopes stabilised with alkali-activated Class F fly ash provides the most effective improvement, with significant increases in factor of safety and reductions in plastic strain zones. Although Class C fly ash moderately improved soil stiffness, it was not fully effective in mitigating deformation. Class F fly ash exhibited similar behaviour to the control sample due to its limited reactivity; however, its performance improved significantly following alkali activation. These findings suggest that, especially in regions where granular fill material is scarce, the slope stability of locally found clay soils can be effectively improved using alkali-activated fly ash. This approach not only enhances slope performance but also contributes to more sustainable geotechnical practices by reducing the consumption of natural resources and lowering overall construction costs.

Keywords

• Slope Stability
• Plaxis 3D
• Fly Ash Stabilisation
• Alkali Activation
• Clay

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