Relationships Between Undrained Shear Strength and Moisture Content of Soil Measured by the Fall Cone Method

Empirical correlations commonly used in geotechnical practice can serve as a valuable tool for estimating the required parameters during the design phase and execution of geotechnical analyses. One of the increasingly important parameters in geotechnical analysis is the undrained shear strength of soil, whose use is also recommended by Eurocode 7 standards, especially when examining the properties of fine-grained soils. Variations in water content significantly influence the consistency state of the soil and have a substantial impact on its behaviour, particularly on shear strength. This study presents correlations between undrained shear strength (cu), determined using the fall cone method, and water content. The results showed a high level of correlation between undrained shear strength and water content, confirming a logarithmic relationship. Empirical equations were applied to enable more accurate estimation of undrained shear strength, with a high coefficient of determination (R²).