Vidalı kazıkların çekme ve basınç kuvveti altında davranışının incelenmesi

Öz

Vidalı kazıklar kullanımı gittikçe yaygınlaşan zemin iyileştirme yöntemlerinden biridir. Bu çalışmada, doğrusal, üçgen ve kare örüntülü grup halindeki vidalı kazıkların çekme ve basınç kuvveti etkisi altındaki davranışları araştırılmıştır. Bu amaçla, literatürde kazıklar üzerinde gerçekleştirilen model deneyler sonlu elemanlar yöntemi ile modellenmiş ve deneysel sonuçlar ile son derece iyi bir uyum elde edilmiştir. Daha sonra deneysel çalışmada kullanılan kazıkların helezon sayısı ve helezon çapları değiştirilerek, helezon sayısı ve çap değişiminin taşıma gücüne etkisi incelenmiştir. Ayrıca vidalı kazıkların yük altındaki davranış ve yenilme yüzeyleri araştırılmıştır. Sonuç olarak, helezon sayısını arttırmak taşıma gücü kapasitesini önemli ölçüde arttırmıştır. Öyle ki, taşıma gücünde elde edilen %100’e varan artış sayesinde, helezon sayısındaki artışın kazık sayısını azaltacak mertebeye geldiği görülmüştür. Ek olarak helezonun çapının 1.8 kat artması ile taşıma gücü değerleri %80 ile %100 arasında artışa neden olmuştur. Bununla birlikte taşıma gücü artışlarının her örüntüde farklı oranda olduğu belirlenmiştir.

Anahtar Kelimeler

• Taşıma Gücü
• Vidalı Kazık
• Plaxis
• Sayısal Analiz
• Çekme ve Basınç Kuvveti

Investigation of the behaviour of screw piles under uplift and compressive forces

Öz

The usage of screw piles is one of the increasingly widespread ground improvement methods. In this study, the behaviour of linear, triangular, and square pattern screw piles in groups under tensile and compressive forces is investigated. The model experiments in the literature on screw piles were modelled by finite element method and a reasonably accurate agreement with the experimental results was obtained. Then, the number of helixes and helix diameters of the screw piles used in the experimental study were changed and the effect of the change in the number of helixes and diameter on the bearing capacity was investigated. Also, the behaviour and failure surfaces of screw piles under load were investigated. In conclusion, increasing the number of helixes significantly increased the bearing capacity. In fact, it was observed that the increase in the number of helixes was sufficient to reduce the number of piles as a result of the increase in the bearing capacity up to 100%. In addition, the increasing the diameter of the helixes by 1.8 times resulted an increase in the bearing capacity values between 80% and 100%. However, it was determined that the bearing capacity increases were different in each pattern.

Anahtar Kelimeler

• Bearing Capacity
• Screw Pile
• Plaxis
• Numerical Analysis
• Tensile and Compression Force

Kaynakça

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