Measuring Axial Friction Factors in Fine-Grained Soil
Measuring Axial Friction Factors in Fine-Grained Soil
Axial seabed resistance plays a key role in the stability of surface-laid pipelines and cables, particularly in soft clays where consolidation and loading history influence resistance mobilisation. This paper presents centrifuge model tests using shallow penetrometers to investigate axial friction under low effective stresses in the range 1-3 kPa representative of pipe/cable-seabed conditions at shallow embedment. The test programme employed model pipes, toroids, and flat ring penetrometers in reconstituted Gulf of Mexico clay, with instrumentation to monitor vertical load, displacement, and pore pressure response. The results show that large changes in axial resistance and friction-factor by a ratio of up to three can emerge due to penetrometer geometry, shearing rate, and lay history, with distinct trends observed under episodic and continuous shearing. The study also highlights practical considerations associated with load control and interpretation at very low stresses when performing these novel tests. When performed with accurate control and interpreted appropriately, centrifuge shallow penetrometer testing provides a robust basis for characterising axial resistance relevant to pipelines, cables, and similar seabed infrastructure.
Colm O'Beirne; Phil Watson; M. Fraser Bransby; David White; Han Eng Low
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Session 3: Resilient geotechnical infrastructure
https://doi.org/10.53243/ICPMG2026-118