Simulating pile set-up in a DEM centrifuge chamber

TY - GEN

T1 - Simulating pile set-up in a DEM centrifuge chamber

AU - Lei, Jiangtao

AU - Arroyo, Marcos

AU - Ciantia, Matteo

N1 - Conference code: 5

PY - 2025

Y1 - 2025

N2 - Pile set-up, defined as the pile shaft capacity increase with time, is a well-established behavioural feature of displacement piles installed in sand. To date, the mechanisms underlying set-up are poorly understood and, as a consequence, is difficult to reliably incorporate this phenomena into design. Micromechanical investigations have recently shown that pile set-up may be directly related to the time dependent breakage of sand around the pile. Following the idea that fracture propagation has an inherent timescale, a fracture based quartz sand discrete element method (DEM) model, previously validated on creep/stress relaxation experimental results, was implemented into a DEM centrifuge chamber to simulate pile set-up. The particle refinement method was implemented to ensure a manageable number of elements. The model pile was either jacked or driven to the target depth. One month creep period under load was applied to age the system. Pull-out pile tests were simulated for the fresh pile and aged pile conditions. The results show a mobilized shaft capacity increase of over 20% for jacked piles and over 50% for driven piles, within the range reported from field pile tests.

AB - Pile set-up, defined as the pile shaft capacity increase with time, is a well-established behavioural feature of displacement piles installed in sand. To date, the mechanisms underlying set-up are poorly understood and, as a consequence, is difficult to reliably incorporate this phenomena into design. Micromechanical investigations have recently shown that pile set-up may be directly related to the time dependent breakage of sand around the pile. Following the idea that fracture propagation has an inherent timescale, a fracture based quartz sand discrete element method (DEM) model, previously validated on creep/stress relaxation experimental results, was implemented into a DEM centrifuge chamber to simulate pile set-up. The particle refinement method was implemented to ensure a manageable number of elements. The model pile was either jacked or driven to the target depth. One month creep period under load was applied to age the system. Pull-out pile tests were simulated for the fresh pile and aged pile conditions. The results show a mobilized shaft capacity increase of over 20% for jacked piles and over 50% for driven piles, within the range reported from field pile tests.

KW - screw pile

KW - helical pile

KW - cyclic loading

KW - installation effect

KW - floating wind

U2 - 10.53243/ISFOG2025-87

DO - 10.53243/ISFOG2025-87

M3 - Conference contribution

BT - Proceedings of the 5TH INTERNATIONAL SYMPOSIUM ON FRONTIERS IN OFFSHORE GEOTECHNICS

A2 - Abadie, C. N.

A2 - Li, Z.

A2 - Blanc, M.

A2 - Thorel, L.

PB - International Society for Soil Mechanics and Geotechnical Engineering

T2 - 5TH INTERNATIONAL SYMPOSIUM ON FRONTIERS IN OFFSHORE GEOTECHNICS 2025

Y2 - 9 June 2025 through 13 June 2025

ER -