Uncertainty analysis on remoulded undrained shear strength of marine clay Academic Article uri icon

abstract

  • Remoulded undrained shear strength su-r is a soil property associated with disturbed clay. This parameter is used to indicate the evolution of the post-failure behaviour of seafloor soil, estimate the rheological properties of debris flows and the drag forces on seafloor structures exerted by a submarine slide, and calculate the penetration resistance of skirt walls. This work discusses the influence of uncertainty on the estimate of empirical relationships between su-r and liquidity index IL as a potential predictor of the remoulded soil strength. Special emphasis is made on assessing the uncertainty inherent to su-r, when the definition of the empirical models is updated from a global to a local (regional) data set. For this purpose two approaches are compared: a parameterisation in the 'log space' (Log-Linear Model, LLM) by transforming least square exponential fitting to log-linear expression, and a parameterisation in the 'physical space' using Bayesian Non-Linear Regression (BNLR). The updating of the trend models conditioned on the two available data sets is performed using simple Bayesian principles. Results show similar trend models obtained by the two approaches, and the standard deviation of the trend indicates different values. A thorough discussion is included based on the different hypothesis considered for the estimate of each model. 2010 Taylor & Francis.

published proceedings

  • GEORISK-ASSESSMENT AND MANAGEMENT OF RISK FOR ENGINEERED SYSTEMS AND GEOHAZARDS

author list (cited authors)

  • Yang, S., Medina-Cetina, Z., & Nadim, F.

citation count

  • 3

complete list of authors

  • Yang, S-L||Medina-Cetina, Z||Nadim, F

publication date

  • March 2010