Effect of dilatancy on tension response of completely rough piles embedded in granular soils

Tolun M., Emirler B., Ertugrul O. L., Yildiz A.

Ocean Engineering, cilt.292, 2024 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 292
  • Basım Tarihi: 2024
  • Doi Numarası: 10.1016/j.oceaneng.2023.116507
  • Dergi Adı: Ocean Engineering
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Applied Science & Technology Source, Aquatic Science & Fisheries Abstracts (ASFA), Communication Abstracts, Compendex, Computer & Applied Sciences, Environment Index, ICONDA Bibliographic, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Dilatancy angle, Finite element model, Pile surface roughness, Sandy soil, Uplift capacity
  • Çukurova Üniversitesi Adresli: Evet

Özet

Pile surface roughness is an important characteristic determining the displacement response of piles under various loading conditions since it leads to surface friction resistance. Considering that no capacity contribution is acquired from the pile tip, the effect of surface friction becomes more pronounced for tension piles. Pile surfaces can be classified as smooth, rough, or completely rough according to the normalized surface roughness value (Rn) of piles, and this paper focuses only on the uplift capacity of piles with normalized surface roughness values greater than 0.1 (i.e., completely rough) by employing the PLAXIS3D code verified against results of twelve physical modelling tests reported in the literature. The reason of selecting piles with completely rough surfaces in this study is that dilatancy behaviour can be only observed in the uplift load-displacement relationships of such piles, unlike the piles with smooth or rough surfaces. While numerical simulations are repeated for different normalized surface roughness values (Rn = 0.2, 0.5, 1.0, and 2.0) and different relative densities of sandy backfill (Dr = 25%, 50%, and 75%), the effect of the pile surface friction resistance on the uplift capacity, which occurs as a result of the interaction between the pile surface and sandy soil grains, is studied with special emphasis on soil dilatancy. It is observed that the numerical results are quite compatible with the physical test results. In addition, increasing the pile surface roughness and relative density of sandy soil causes an increase in the uplift capacity, and those capacity increments can only be modelled properly by increasing the dilatancy angle of sandy soil in finite element analyses.