Investigation of the coefficient of consolidation of fine-grained soils using combined apparatus

Abstract

The scope of this investigation is to compare the coefficient of consolidation (cv) values defined by the Taylor's Square Root of Time Fitting Method, which is obtained from the conventional oedometer tests, with the cv values calculated by Terzaghi's One-Dimensional Consolidation Theory, which is obtained from the permeability-consolidation tests performed with a combined apparatus specifically designed for this study. In addition, an empirical relation is developed to determine cv using the coefficient of permeability (k) and index properties of the soils. The cv values obtained from the permeability-consolidation tests using the combined apparatus were found to be larger than the cv values defined by the Taylor's Method, which is one of the oedometer tests. The findings showed that the difference was more prominent in the soil samples with a high plasticity. It was also found that the cv calculated by the Taylor's Method exhibited a distribution in a wide range with the increased load depending on the degree of plasticity of the soil. The cv obtained from the combined apparatus it decreased with low load values and increased with higher loads levels. The cv obtained by the proposed empirical relationship showed good agreement with the cv defined by permeability-consolidation relationships.