Simple Methodology to Obtain Critical State Parameters of Remolded Clays Under Normally Consolidated Conditions Using the Fall-Cone Test

Abstract

The falling cone is widely used as a laboratory test to determine the liquid limit for the characterization of clay soils. However, remolded undrained shear strength and deformability and strength parameters of critical state models can also be estimated. The objective of this paper is to show a simple methodology to determine these important parameters for engineering simulations. Controlled laboratory tests were carried out on kaolin clay samples using a cone with 30° of tip angle and 30 g of mass. Mini-vane tests were also performed to determine the remolded undrained shear strength of the samples. The experimental results were used to calibrate the Hansbo cone factor, K, from which it is possible to relate the undrained shear strength and the cone penetration for different water contents. The study shows that a calibrated cone and the proposed methodology may be used to estimate strength and deformability parameters for preliminary stages of design involving remolded clays under normal consolidation conditions in a quick way and at very low cost.