Numerical Simulation of Conductor Casing Driving in Fully Saturated Clay Soil
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This study aims to simulate the installation of a conductor casing by impact hammering in fully saturated clayey soil. A numerical model based on the Material Point Method (MPM) is used to capture the complex soil–structure interaction during the driving process. The model employs a two-phase explicit formulation in a 2D axisymmetric framework to represent the undrained behavior of the clay. The conductor casing is idealized as a rigid body that interacts with the surrounding soil through an adhesive contact algorithm, while a moving mesh strategy is employed to preserve computational accuracy near the casing boundary. The simulation incorporates both the initial self-weight penetration phase and the subsequent impact-driven phase. Results indicate that soil resistance increases with depth as expected, leading to a stabilization of the penetration rate as the casing is driven further into the soil. In addition, the numerical analysis reveals that the impact force plays a crucial role in overcoming local soil resistance and in generating excess pore pressures, which facilitate the casing’s advancement. The study demonstrates that the Material Point Method is highly effective for simulating large deformations and complex contact interactions in saturated clays. The adopted approach provides detailed insights into the dynamic behavior of both the soil and the casing during impact hammering. In conclusion, this work offers a reliable numerical tool for predicting the performance of conductor casing installations under challenging offshore conditions. The findings contribute to the optimization of installation parameters, enhancement of safety measures, and reduction of operational time, thereby advancing offshore geotechnical engineering practices. Sensitivity analyses reveal that variations in impact force and soil properties influence penetration behavior, emphasizing the necessity for precise calibration to achieve dependable simulation outcomes.