STUDY OF RHEOLOGICAL PROPERTIES OF THE LACUSTRINE SOFT SOIL UNDER DIFFERENT STRESS LEVEL

In order to understand the rheological properties of lacustrine soft soil at different stress levels，a onedimensional indoor consolidation creep test was carried out on soft soil in the Dongting Lake area． A rheological constitutive model under lateral confinement conditions was then constructed，and the analytical solution was obtained under one-dimensional consolidation conditions according to the fitted rheological constitutive model． The results indicate that soft soil in the Dongting Lake area has obvious nonlinear creep characteristics． When the stress level is lower than a certain stress threshold，the rheological properties of soft soil follow the rules of the Schiffman model， and the consolidation rate of the soil is low． When the stress level is higher than a certain stress threshold，the rheological properties of soft soil follow the rules of the Nishihara model，and the consolidation rate of the soil is high． In addition，the consolidation rate increases with the increase of the stress threshold． Therefore，in the engineering construction phase of a lacustrine soft soil area，different settlement formulas and engineering treatment measures should be adopted according to the engineering properties of the soft soil and the applied load．