TITLE:
Using Piezocone Dissipation Test to Estimate the Undrained Shear Strength (su), Nkt and NΔu Factors in Cohesive Soils
AUTHORS:
Dante René Bosch, Rubén Rafael Sotelo, Fernando María Mántaras
KEYWORDS:
CPTu Piezocone, Overconsolidation Ratio, Undrained Shear Strength, Dissipation Test
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.7 No.8,
August
16,
2019
ABSTRACT:
The current practice of geotechnical engineering
commonly uses a combination of theoretical and empirical correlations to
estimate the soil undrained shear strength in clays from the piezocone test. In
order to complement the use of such correlations, the application of a method
to estimate the soil undrained shear strength, using measures of the excess
pore pressure in dissipation tests of piezocone is presented. In cohesive
soils, excess pore pressure and undrained shear strength are dependent on the
same variables (stress state, stress history, soil stiffness), which allows them
to be related by the theoretical cavity expansion-critical state framework.
This paper mentions the mathematical formulation that supports the theoretical
framework used, its relationship with the Nkt and NΔu factors and their estimation in a case studied. The results
obtained are consistent within the dispersion found in the international
literature and encourage the use of the method in engineering practice.