Research On The Rheological Model Of Fine Sand With High Salt By Uniaxial Compression Tests

Firstly, this paper introduced the research status of properties of saline soil and sand rheological at home and abroad. At present, the study of saline soil engineering properties was concentrated in the salt expansion effect and salt transport mechanism of soil with sulphates and carbonates. There are fewer studies on the influence of engineering properties of the rock and soil with chloride, and few studies on rheological properties of sand with high salt. More and more infrastructures would locate on the sand areas with high salt as the construction of infrastructure scale up. It does definitely make the long-term safety of infrastructure greatly reduced without considering the rheological properties of sand with high salt.Secondly, in order to research the rheological properties of fine sand with high salt, sand samples with different water content and different salt content were compressed by different pressure. Based on the experimental data, analyzed the creep process of fine sand with different water content, different salt content and different pressure from a qualitative view, and also analyzed the mechanism of effect of moisture content and salt content. Two rheological models which have three units were chose to describe the rheological properties of fine sand with high salt after analyzed characteristics of each creep curve. After analyzed the suitability of the two models with OriginPro8.0 software, only H-K model was chose to describe the rheological properties of fine sand with high salt in the end. Based on the experimental data, three rheological parameters of H-K model were fitted out with the nonlinear fitting function of OriginPro8.0 software. According to the fitting results, three rheological parameters of H-K model were found have a significant change when water content, salt content and pressure changed. According to the change regulation of each parameter as different influence factors changed, each parameter was expressed as binary linear function that variables are water content and pressure, and also fitted out each parameter of all functions.At last, based on the theory of layering summation method, checking computation calculations of simplified model of roadbed which located in the area where fine sand with high salt has been done, and also compiled its computer program with Visual Basic.NET programming language. After compared calculation data to the real data, it’s found that both the final deformation amount and the stabilization time of calculation data were less than the final deformation amount and the stabilization time of the real date. Aimed at making could predicted the long-term deformation amount of saline sand area more precise. A central-difference format was derived for three-dimensional H-K rheological model according to the finite difference method of FLAC3 D software, and also offered its algorithm-flow chart.