Research On The Prediction Of Settlement Of Loess Embankment Foundation

Through a large number of laboratory tests, Yan’an remolded loess’ s compression, rheology and infiltration characteristics were analyzed, and of the Yenan loess embankment final settlement and the settlement process was studied by the soil mechanics principle, and obtained the following main achievements:(1) The experimental study showed that the Yan’an loess silt content accounts for about 76%, clay particle content of about 15%, fine sand content accounted for about 9%, liquid limit was 25.5%, and the plastic limit was 16.7%, and the optimum water content is about 14%, maximum dry density is 1.78g/cm3, and remolded loess has medium compression, when the water content is smaller and has a high dry density with low compression.(2) By high pressure consolidation test results are fitted, obtaining respectively remolded loess the quantitative relationship between stress and strain, between void ratio reciprocal, density and load, and based on remolded loess power function of the relationship between stress and strain and dry density, and load the hyperbolic relationship are established on the basis of the continuous uniformly distributed load and under the action of self weight loess embankment foundation of the final settlement prediction formulas. The method is used to predict the settlement amount and field monitoring results are basically the same.(3) To establish the stress-strain-time experience equation of remolded loess, the loess embankment foundation under the action of gravity change of settlement prediction formulas, and compared with monitoring data analysis shows that the formula can simulate during construction and after construction settlement changes with the time.(4) Based on the Kelvin rheological model of five elements, derived from loess embankment in uniform loads of settlement with time change the equation.(5) The permeability coefficient of Loess by initial soil water content, initial dry density and void ratio of larger, the permeability coefficient decreases with the increase of the initial water content increases linearly decreasing, with initial dry density increase and decrease index, and void ratio between a power function relationship.(6) Based on Terzaghi saturated consolidation theory, consider the rheological properties of loess embankment, saturated loess embankment foundation of rheological consolidation coupled differential equations are established, and Laplace transform and Fourier transform is derived out the analytical solution.(7) According to the nonlinear consolidation theory of saturated soft clay, combined with the infiltration of loess embankment and compression properties, pore ratio as the independent variable is saturated loess embankment of one-dimensional nonlinear consolidation equations.