Numerical Evaluation of Scour-Hole Formation Procedures in Centrifuge Modelling for Laterally Loaded Monopiles
Numerical Evaluation of Scour-Hole Formation Procedures in Centrifuge Modelling for Laterally Loaded Monopiles
In centrifuge model tests involving the investigation of scour on lateral bearing capacity of monopiles, the scour hole is often pre-excavated at 1g, followed by acceleration to the target gravity Ng before lateral loading is applied. However, this preparation sequence may alter the initial stress state and stress path during scour hole formation, potentially compromising the extension of test results to prototype conditions. This study establishes two comparative simulation schemes using FEM modelling at the centrifuge model scale: (A) 1g scouring → acceleration to Ng → lateral loading, and (B) acceleration to Ng → Ng scouring → lateral loading. The acceleration process is simulated via incremental self-weight multipliers ΣMweight. The results demonstrate quantifiable discrepancies between the two schemes in terms of pile-top load-displacement response, ultimate soil resistance, and initial stiffness. Scheme A tends to underestimate the lateral bearing capacity of the monopile compared to Scheme B. These differences are primarily attributed to the unloading stress history during the scouring stage and the subsequent soil stress redistribution around the monopile. This research provides a valuable benchmark for assessing the applicability of simplified centrifuge scour test procedures and facilitates the integration of numerical and physical modelling.
Ben Wu; Siau Chen Chian
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Special Session 5: Combination of numerical and physical modelling
https://doi.org/10.53243/ICPMG2026-262