LAUSR

The undrained shear strength (su) of cohesive soils is a crucial parameter for many geotechnical engineering applications. Due to the complexities and uncertainties associated with laboratory and in situ tests, it is a challenging task to obtain the undrained shear strength in a reliable and economical manner. In this study, a probabilistic model for the su of moderately overconsolidated clays is developed using the Bayesian model class selection approach. The model is based on a comprehensive geotechnical database compiled for this study with field measurements of field vane strength (su), plastic limit (PL), natural water content (Wn), liquid limit (LL), vertical effective overburden stress ($$\sigma_{\nu }^{\prime }$$σν′), preconsolidation pressure ($$\sigma_{\text{p}}^{\prime }$$σp′) and overconsolidated ratio (OCR). Comparison study shows that the proposed model is superior to some well-known empirical relationships for OC clays. The proposed probabilistic model not only provides reliable and economical estimation of su but also facilitates reliability-based analysis and design for performance-based engineering applications.