Constitutive Parameters Estimated by Plasticity Index

Abstract

A large testing program, consisting of triaxial compression, triaxial extension, and oedometer tests on 12 artificially prepared soils was performed. The soils exhibited a wide range in plasticity index, from 10–55. These tests were performed to study whether it is possible to determine parameters specifying a constitutive soil model simply by using the plasticity index. Linear correlations between the soil parameters for constitutive equations and the plasticity index were obtained with high values noted in the coefficients of correlation. Numerical illustrations to check the overall accuracy of the correlations were also developed. Direct application of these correlations to undisturbed natural clays will require further research.