Stress wave analysis of monopile driving in sand informed by embedded fibre Bragg grating sensors
Stress wave analysis of monopile driving in sand informed by embedded fibre Bragg grating sensors
ABSTRACT: Stress wave propagation in monopiles during driving is conventionally analysed using Pile Driving
Analyzer (PDA) sensors mounted at the pile head. PDA acceleration measurements can be interpreted through one-
dimensional stress wave theory and signal matching techniques. However, the limited spatial resolution of the PDA
measurements leads to non-unique solutions, resulting in interpretations of the distributed shaft and base resistances that
are inevitably subjective. The PICASO (PIle Cyclic AnalySis: Oxford and Ørsted) joint industry and research project
enabled the acquisition of high-resolution strain data along the embedded length of medium-scale field test piles by
incorporating below-ground optical fibre Bragg grating (FBG) sensors as part of the instrumentation. Using a hybrid PDA
and FBG signal matching approach, proven and validated in previous studies, this paper reports on applications of stress
wave propagation analysis for pile driving in homogeneous silica sand. The enhanced PICASO field data from both PDA
and FBG sensors significantly constrain the stress wave solution space, yielding insights into the development of soil
resistance to driving, a critical factor for accurate driveability predictions. The obtained hybrid signal matching results
are compared with the shaft and base resistances predicted using a well-known empirical method.
Magne Rasmussen; Vincenzo Nardelli; Rachel Keane; M. Roisin Buckley; H. J. Burd; W. Byron Byrne
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Special Session 3: Physical Modelling of Installation of Fixed OWT Foundations
https://doi.org/10.53243/ICPMG2026-298