Simulation of pile installation in chalk: discrete and continuum approaches

1. Home
2. Publications
3. Online Library
4. Simulation of pile installation in chalk: discrete and continuum approaches

Publication Title
Simulation of pile installation in chalk: discrete and continuum approaches

Abstract
Chalk is a type of porous rock formed from cemented calcite grains. It is widely found in areas across the UK, and is present beneath the North Sea where offshore wind turbines are being installed. Large piles are often driven into chalk to support these turbines. However, the installation process can cause the intact rock below the pile to crush, creating a putty-like material with different mechanical properties from the original rock. This unpredictability has made it difficult to design piles that are appropriate for use in chalk. This paper presents two approaches to modelling open-ended pile instal- lation in chalk. The first approach is based on the Discrete Element Method (DEM), which represents the rock as separate particles bonded together. A new contact model is proposed for highly porous rocks. The second approach uses the Geotech- nical Particle Finite Element Method (GPFEM), which has been adapted to account for the large displacements and nonlin- earities of the problem. With GPFEM the coupled hydromechanical effects developing during pile installation are investi- gated using a robust and mesh-independent implementation of an elasto-plastic constitutive model at large strains. With DEM the micromechanical features of pile plugging are explored and the mechanisms behind radial stress distributions inside and outside the plug are unveiled. Although both approaches have their challenges, they have been successful in modelling pile installation experiments at model scale. This offers the potential for a closer examination and improved understanding of the mechanisms underlying open-ended pile installation in chalk.
Authors
Matteo Oryem Ciantia; J. Zheng; M. Previtali; Jonathan A. Knappett

Published In

18th European Conference on Soil Mechanics and Geotechnical Engineering (ECSMGE2024)

Theme

E - Environment, water and energy

Download PDF