Test And Analysis On Liquid Rheological Model Of Soft Soil

Soft soil is a complex natural porous media, which is widely distributed in the coastal areas, wetlands,rivers, lakes and other areas. In recent years, with the rapid development of economy and the improvement of urbanization, more and more projects of sofe soil are developed and used. A lot of tests research and practice of engineering show that the deformation of soft soil takes a long time to achieve stability. The liquid rheological properties that the strain of the soft soil growth with the time changing, is likely to cause the building which were built on the soft soil foundation construction produce the post-construction settlement that cannot be ignored. It can carry the influence of the strength, stability and safety and durability to the building. For this reason, this paper use the method that combins tests with theories to analyze numerial modeling about the physical shape, distribution and content of rheological phase material in the soft soil.In order to analyze the relationship between liquid rheological properties of soft soil and rheological phase material in different shape and distribution, this work uses the disguised soil that combines rheological phase material in different shape and distribution artificial soil with the non-rheological phase material to do one-dimensional compression creep test. In order to analyze the relationship between model parameters and rheological phase material, composite creep element model with the Duncan non-liner modulus of elasticity is used to obtain the fitting parameters of the stress-time curve figure.This paper carries out the researches and achievements are mainly including the following several aspects:(1) The influence of rheological phase material shape and distribution on rheological properties were analyzed. Based on the experimental analysis, whatever the shap of rheological phase material is, as the distribution uniformity of rheological phase material increases, the average coefficient of viscosity which describes the mainly characterization of liquid rheological properties reduces and then stabilize. It shows that the liquid rheological property of the soil have nothing to do with rheological phase material shape and distribution.(2)Use the composite soft soil rheological model which introduces Duncan non-linear modulus of elasticity to describe the relationship between the distribution of rheological phase material and soil liquid rheological properties. Based on the test data, the model parameters were obtained by fitting data. As the distribution uniformity of rheological phase material increases, the changes of the model parameters tend to be stabled that verifies the liquid rheological properties of the soil have nothing to do with the distribution of the rheological phase material.(3) By using the composite creep element model with the Duncan non-liner modulus of elasticity, the stress-time curve figure of the sample with different rheological phase material content can be obtained, and also the fitting parameter, then relationship between content of rheological phase material and fitting parameters is analyzed. Based on the result of the direct shear creep test and one dimensional compress creep test with different content of rheological phase material, the rheological properties under multilevel load can be properly described, and the hyperbolic equation of model parameters can also be obtained when the composite creep element model with the Duncan non-liner modulus of elasticity is controlled on one dimensional condition.