TY - JOUR
T1 - DEM study of particle scale effect on plain and rotary jacked pile behaviour in granular materials
AU - Cerfontaine, Benjamin
AU - Ciantia, Matteo O.
AU - Brown, Michael
AU - White, D. J.
AU - Sharif, Yaseen U.
N1 - Copyright:
© 2023 Published by Elsevier Ltd.
PY - 2023/9
Y1 - 2023/9
N2 - The capacity of open-ended piles strongly depends on the potential plugging occurring during installation. The Discrete Element Method (DEM) is particularly suitable to the study of pile plugging, as it can model large soil deformation. However, DEM simulation of the 3D boundary value problems is computationally expensive, and particle upscaling is usually used to reduce the number of particles modelled. In this paper, two granular beds were created with the same average porosity, initial stress field and contact parameters, but different particle scales. Two pile geometries were installed by plain and rotary jacking. Normalised results show that the pile penetration mechanism is strongly affected by the particle scale. Larger particles lead to earlier pile plugging, higher shaft resistance and require a greater force to penetrate the ground. This effect can be linked to a modified penetration mechanism, with larger shear zones and less well defined “nose cone” under the pile tip for larger particles. Changing particle scaling has a neutral effect on the total penetration resistance of a rotary jacked pile, but reduces the base penetration and increases the plug resistance. Maximising the ratio of particle scale to wall thickness is key to adequately capturing the pile coring mechanism.
AB - The capacity of open-ended piles strongly depends on the potential plugging occurring during installation. The Discrete Element Method (DEM) is particularly suitable to the study of pile plugging, as it can model large soil deformation. However, DEM simulation of the 3D boundary value problems is computationally expensive, and particle upscaling is usually used to reduce the number of particles modelled. In this paper, two granular beds were created with the same average porosity, initial stress field and contact parameters, but different particle scales. Two pile geometries were installed by plain and rotary jacking. Normalised results show that the pile penetration mechanism is strongly affected by the particle scale. Larger particles lead to earlier pile plugging, higher shaft resistance and require a greater force to penetrate the ground. This effect can be linked to a modified penetration mechanism, with larger shear zones and less well defined “nose cone” under the pile tip for larger particles. Changing particle scaling has a neutral effect on the total penetration resistance of a rotary jacked pile, but reduces the base penetration and increases the plug resistance. Maximising the ratio of particle scale to wall thickness is key to adequately capturing the pile coring mechanism.
KW - Piles
KW - Plugging
KW - Discrete Element Method
KW - Granular material
KW - Pile jacking
KW - Rotary jacking
UR - http://www.scopus.com/inward/record.url?scp=85161334482&partnerID=8YFLogxK
U2 - 10.1016/j.compgeo.2023.105559
DO - 10.1016/j.compgeo.2023.105559
M3 - Article
SN - 0266-352X
VL - 161
JO - Computers and Geotechnics
JF - Computers and Geotechnics
M1 - 105559
ER -