Determination of Slimes Consolidation Parameters from Instrumented Column Measurements

Prediction of the consolidation behaviour of fine-grained saturated materials is of significant interest in a wide range of industrial and environmental fields. It is classically achieved using the s’(e) and k(e) constitutive laws that relate effective stress s’, permeability k and void index ratio e. This work compares two approaches for estimation of the consolidation laws from instrumented column measurements: a direct method and a reverse method. The former requires that successive void index ratio e(h) and excess pore pressure u’(h) time profiles be converted into a set of (s’;e) and (k;e) data points, from which the s’(e) and k(e) parameters can be determined by direct regression. With the latter, the s’(e) and k(e) parameters are determined by matching the measured e(h) and u’(h) profiles with those predicted using a finite element consolidation simulation code. It is found that the reverse method, which is ideally suited for simulation work yields more accurate and less biased parameter estimates.