Impact of the installation on the long-term cyclic behaviour of piles in sand: A numerical study. Issue 138 (November 2020)

• Record Type: Journal Article
• Authors: Staubach, P.; Machaček, J.; Moscoso, M.C.; Wichtmann, T.
• Is Part Of: Soil dynamics and earthquake engineering. Issue 138(2020)
• Publication Date: 2020-11
• Subjects: Pile driving -- High-cyclic loading -- High-cycle accumulation model -- Coupled Eulerian-Lagrangian -- Partially drained; Soil dynamics -- Periodicals; Earthquake engineering -- Periodicals; Sols -- Dynamique -- Périodiques; Génie parasismique -- Périodiques; 624.176205
• DOI: 10.1016/j.soildyn.2020.106223
• Languages: English
• ISSNs: 0267-7261

Abstract

Abstract: The installation process changes the state of the soil in the vicinity of a pile and therefore influences its load-displacement behaviour during the operational phase following the installation. The installation process itself and its effect on the pile behaviour under a subsequent high-cyclic loading are numerically investigated in this work. Two different installation techniques, namely impact driving and jacking, are investigated using a coupled Eulerian-Lagrangian approach in combination with a hypoplastic material model. Either ideally drained or partially drained conditions are assumed. Afterwards the pile response to a high-cyclic loading with up to five million load cycles is studied using a high-cycle accumulation (HCA) model. Compared to a wished-in-place (WIP) pile, the simulations accounting for the installation process showed considerable less permanent pile displacements in case of initially medium dense sand. However, the opposite was observed in case of initially dense sand. Current practice assuming a WIP state as the starting point in numerical simulations seems thus to be conservative for initially medium dense sand but leads to an underestimation of permanent deformations for initially dense sand. Highlights: Coupled Eulerian-Lagrangian (CEL) method considering partially drained conditions for problems with high accelerations. Simulation of pile installation considering partially drained conditions using the CEL method. Influence of the installation on the long-term cyclic behaviour using the high-cycle accumulation (HCA) model.