Determination of the overconsolidation ratio and undrained shear strength of cohesive soils by CPTu measurement

Abstract

Estimations of the undrained shear strength (Su) and overconsolition ratio (OCR) of cohesive soil are essential for the evaluation of geology investigation. In comparison to time-consuming laboratory tests, the field piezocone penetration test (CPTu) can rapidly evaluate these parameters. However, existing studies have mainly relied on empirical correlations to estimate the undrained shear strength Su and OCR from CPTu measurements. These correlations are mainly empirical, involving fixed coefficients multiplied by CPTu measurement. Based on the coupled Eulerian-Lagrangian method, this study employed large deformation finite element modeling to summarize and extend the relationships between CPTu measurement and the estimation of undrained shear strength Su and OCR in cohesive soils. These relationships allow for predictions based on CPTu measurements without the requirement for laboratory calibration or referencing to field benchmarks. The accuracy and applicability of the proposed prediction formulas are validated through field case studies for comparative analysis.