Undrained shear strength prediction of clays using liquidity index

Liquidity index is used to measure the relative consistency of natural soils, making it possible to evaluate the stiffness degree and strength of clays. However, a systematic understanding of the relationship between the undrained shear strength and the liquidity index remains unclear. While some studies are being conducted on this putative relationship, the theoretical foundation is still lacking. This study proposes a new undrained shear strength prediction model based on the Mohr–Coulomb failure criterion and the critical state theory. A database of 103 soil samples from 18 research is utilised to validate the model’s applicability. The results reflect a consistent level of accuracy. The proposed model has an obvious advantage and has potential for predicting the undrained shear strength of clays.