A VERIFICATION ANALYSIS FOR PILES IN LIQUEFIABLE SOIL

Abstract

The soil loses its strength and behaves like a liquid when the increasing the pore water pressure under dynamic loads in saturated sandy soils. The large soil displacements can occur on liquefied soils. Pile foundations are applied to bearing capacity problems soil which may be subjected to large lateral displacements due to liquefaction. Although there are many theoretical and practical studies on the behavior of laterally loaded piles in liquefiable soils, there is still no definitive method. The pile damages which are occurred by lateral spreading resulting from liquefaction under dynamic loads have been investigated by many scientists and studies on the causes of damages have increased. Pile response in liquefiable soils and the evaluation of its possible damage are generally assessed by using some available numerical method, for example: finite difference (FDM), finite element (FEM) and boundary element (BEM) methods. In this paper, the FDM method is used to study the pile behavior in liquefiable soils and its reliability is checked by comparison with centrifuge test results from literature. It, in which the effect of liquefaction-induced lateral spreading on pile was evaluated, are also studied. Finally, the analysis results with FLAC 2D are compared with those observed in a centrifuge experiment.

Keywords

• Liquefiable Soil
• Pile Foundation
• FLAC 2D
• Finite Difference Method

A VERIFICATION ANALYSIS FOR PILES IN LIQUEFIABLE SOIL

Abstract

Suya doygun kumlu zeminlerde dinamik yükler altında boşluk suyu basıncının artması sonucunda zemin mukavemetini kaybeder ve sıvı gibi davranır. Bunun sonucunda sıvılaşan zeminlerde büyük zemin yerdeğiştirmeleri meydana gelebilir. Taşıma gücü problemleri olan zeminler için kullanılan kazık temeller sıvılaşma olayından dolayı büyük yanal yerdeğiştirmelere maruz kalabilirler. Yatay yüklü kazıkların dinamik yükler altındaki davranışını üzerinde yapılmış birçok nümerik ve deneysel çalışmalar olmasına rağmen, sıvılaşan zeminlerdeki kazık davranışlarını kesin yargılarla belirlemek çok mümkün değildir. Dinamik yükler altında meydana gelen sıvılaşma ve sıvılaşma sonucunda oluşan yanal yayılmanın kazıklarda meydana getirdiği hasarlar birçok bilim adamı tarafından araştırılmış ve oluşan hasarların sebepleri üzerinde yapılan çalışmalar artmıştır. Sıvılaşan zeminlerde kazık davranışı belirlemek için kullanılan bazı sayısal yöntemler mevcuttur, örneğin; sonlu farklar metodu (FDM), sonlu elemanlar metodu (FEM), sınır eleman metodu (BEM). Bu çalışmada, sıvılaşan zemindeki yanal yüklü kazık davranışının analiz sonuçları ile literatürden alınan santrifüj deney sonuçları karşılaştırılmıştır. Sayısal analizler FLAC2D sonlu farklar programı kullanılarak yapılmış elde edilen sonuçlar santrifüj deney sonucu ile kontrol edilmiştir.

Keywords

• Sıvılaşan Zemin
• Kazık Temel
• FLAC 2D
• Sonlu Farklar Metodu

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