Recognising Geotechnical Uncertainty as an Asset to Site Investigation and Characterization

Publication Title
Recognising Geotechnical Uncertainty as an Asset to Site Investigation and Characterization

Abstract

ABSTRACT: Geotechnical field and laboratory data are typically presented in a factual report, as nominal values, without systematic documentation of uncertainty. These data are used in calculations, correlations and design, where error in the input data and subsequent correlations combine to a compound error that may be significant and increase risk. Uncertainty is ever present in geotechnical data, from inherent soil uncertainties (aleatory) to systematic uncertainties in methods and analysis (epistemic). We describe sources of geotechnical uncertainty in offshore geotechnical data collection, laboratory analysis and interpretation, and evaluate those uncertainties within two commonly used geotechnical parameter calculations and correlations. Through worked examples using representative tolerances from relevant standards, guidance and conventional working practice, the propagation of uncertainty is illustrated for the calculation of Undrained Shear Strength and Relative Density. The presentation of error propagation and uncertainties to end-users of data are demonstrated and discussed, highlighting the importance of recognising uncertainties.

Authors
KIERAN BLACKER; N. Dyer; E. Tataki; Sean Kilburn

Published In

5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG2025)

Theme

17 - Design Standards, Certification and Risk Mitigation

DOI
https://doi.org/10.53243/ISFOG2025-447

International Society for Soil Mechanics and Geotechnical Engineering

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