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The buckling of steel pipe piles during installation is numerically studied. Generally, numerical simulation of installation processes is challenging due to large soil deformations. However, by using advanced numerical approaches like Multi-Material Arbitrary Lagrangian-Eulerian (MMALE), such difficulties are mitigated. The Mohr-Coulomb and an elastic-perfectly plastic material model is used for the soil and pile respectively. The pile buckling behavior is verified using analytical solutions. Furthermore, the model is validated by an experiment where a pipe pile is driven into sand using vibratory loading. Several case scenarios, including the effects of heterogeneity in the soil and three imperfection modes (ovality, out-of-straightness, flatness) on the pile buckling are investigated. The numerical model agrees well with the experimental measurements. As a conclusion, when buckling starts, the penetration rate of the pile decreases compared to the non-buckled pile since less energy is dedicated to pile penetration given that it is spent mainly on buckling.

Pipe-piles are installed using impact or vibratory driving which influences the soil in different ways including the void ratio and stress distribution. Such complex problems are hard to investigate on the field as well as using numerical methods. Here, a sophisticated numerical approach is employed to evaluate the soil behavior during pile installation. Also, a sensitivity analysis on the frequency and the impact duration is done for vibratory and impact driving, respectively. The investigation includes the required force of the pile installation, pile penetration behavior, plugging formation inside the pile, and the change of the soil state including the change in the horizontal stress and density around the pile during the installation. Results of the numerical model show several advantages of vibratory driving over impact driving in the dense sand including, reaching the designated depth using less momentum and work as well as more soil compaction.

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Two of the mesh-based numerical approaches suitable for geotechnical large deformation problems, the multimaterial ALE (MMALE) and the Coupled Eulerian-Lagrangian (CEL) methods are investigated. The remeshing step in MMALE is claimed to hold advantages over CEL, but its effects on application problems are not studied in detail. Hence, the possible capabilities and improvements of this step are studied in three large deformation geotechnical problems with soil-structure interaction. The problems are validated and verified using experimental and analytical solutions, respectively. By using the remeshing step in MMALE, a smoother material interface, lower remap-related errors, and better computation cost are achieved.