Mechanical Analysis Of Soil Under Traffic Loads

In this paper, the introduction of the research contents, research tasks and research significance about vehicle-terrain mechanics is given. Something of the study in this field at home and abroad, with some problems and prospects in the future development of this subject are summarized. Also some basic theories and methods which are needed to work over on terra-mechanics are generalized, including the elastic and plastic theory of soil, the simulation of traffic loads and some basic definition, theories about Finite Element Method.Different from traditional method, in the process of calculation two different methods to load in the element simulation are used, including uniform and non-uniform loading. We calculate the stress, strain and displacement value of soil structure under mobile constant loads and harmonic loads, and analysis comparatively. The vehicles-ground experiment was designed and done. And after the experiment the data tested in the laboratory and the element results are compared, fitted well. The mail contents are as follows:1 .Considering the characteristics of transportation loads, static load is decided to simulate traffic loads. The project to be studied is simplified as a problem of plane-strain, and the software of ANSYS is used to model and calculate the problem. We discuss the law of stress and load, and give the distribution in MATLAB, which can provide a certain reference and application value for the engineering.2.Next movable invariable load and moving and time-harmonic loads are decided to simulate traffic loads. ANSYS is used to model and calculate the problem. We discuss the changes which are impacted by load and speed in the law of structure stress, strain and displacement under movable invariable load and harmonic loads without considering horizontal force. For different combinations conditions by five kinds of vehicles and seven different speeds, we calculate numerical results of the stress, strain and displacement of the soil structure, and also give the distribution in MATLAB.3.Considering level force factor, we analysis the interaction of vehicles and road in the cases of car braking and normal traffic. For different coefficients of level force, we calculate the stress, strain and displacement respectively, and the experience equation is given about its results.4. Compared to the element results, the data which is testing in the laboratory is used to verify the accuracy of the calculation model and results. In this paper, there are two points of innovation: one is two different methods are used to load in the process of finite element calculation, and the data is dealt and handled. The other is the vehicles-ground experiment is designed and done.