An Experimental and Numerical Investigation of Bell Type Anchor Plates Embedded in Sandy Soil

Öz

Foundations are often subjected by pressure loads. However, the foundations of structures such as high-rise building, wind turbines for generating electricity etc. which is exposed to lateral loads such as wind load etc. are generally subjected to uplift loads. It is necessary to examine the effect of this uplift force when designing the foundation of such subjected loads. In this study, the uplift capacity of bell type anchors embedded in a sandy soil was investigated experimentally and numerically. Bell type anchors with base diameters of 50, 100 and 150 mm were used. The effect of the parameters such as the angle of the sloping surface and embedding depth of the bell type anchor and relative density of the sand where the anchor was buried on the uplift capacity were investigated. Also, the uplift capacities of helical and circular anchors are found experimentally and compared with the uplift capacity of the bell type anchors. As a result of this study, the uplift capacity is not significantly affected by the change of the anchor angle and the uplift capacity decreases slightly as the anchor angle increases. In addition, the uplift capacity increases as the diameter and embedding depth of the bell type anchor, relative density of the sand where the anchor was buried increases.

Anahtar Kelimeler

• Bell type anchor,Uplift capacity,Circular anchor,Helical anchor

Kum Zemine Gömülü Çan Tipi Ankrajların Deneysel Çalışmalar ve Sayısal Analizler ile İncelenmesi

Öz

Temeller genellikle basınç yüklerine maruz kalmaktadır. Fakat rüzgar yükü vb. gibi yanal yüklere maruz kalan yüksek binalar, elektrik üretmek için kullanılan rüzgar tribünleri vb. gibi yapıların temelleri çekme yüklerine maruz kalmaktadır. Bu tip yüklere maruz yapıların temelleri tasarlanırken bu çekme kuvvetinin etkisini incelemek gerekmektedir. Bu çalışmada kum zemine gömülü çan tipi ankrajların çekme kapasitesi deneysel çalışmalar ve numerik analizlerle incelenmiştir. Deneysel çalışmalarda ve sayısal analizlerde taban çapı 50, 100 ve 150 mm olan çan tipi ankrajlar kullanılmıştır. Çan tipi ankrajın eğimli yüzeyinin açısı, gömülme derinliği ve gömüldüğü kum zeminin sıkılığı gibi parametrelerin çekme kapasitesine etkisi araştırılmıştır. Ayrıca helisel ve dairesel ankrajların çekme kapasiteleri deneysel olarak bulunarak çan tipi ankrajların çekme kapasiteleri ile kıyaslanmıştır. Bu çalışmanın sonucunda görülmüştür ki, çekme kapasitesi ankraj açısının değişiminden çok fazla etkilenmemektedir ve çekme kapasitesi ankraj açısı arttıkça az bir miktar azalmaktadır. Ayrıca, çan tipi ankrajın çapı, gömülme derinliği ve gömüldüğü kumun rölatif sıkılığı arttıkça çekme kapasitesi artmaktadır.

Anahtar Kelimeler

• Çan tipi ankraj,Çekme kapasitesi,Dairesel ankraj,Helisel ankraj

Kaynakça

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