| As a special material for civil engineering, geogrids has been widely used in the world increasingly with it’s characteristics of high strength, well flexibility, corrosion resistance, pre-fabricate and convenient transportation. The geogrids will show different elastic-plastic cha-racteristics under the short and long term loads, which will directly influence the geogrids ser-vice life. Meanwhile, it has great significance to study reinforced soil drawing interface since it affected the stability of reinforced soil structure. In this paper, the author widely collected re-lated research about geogrids test and mechanical characteristics both at home and abroad, and mainly analyzed the existing geogrids elastic viscoplastic theoretical model, then put forward the variational theoretical model. Also in this paper, the author presents the distribution formula about geogrids drawing force after systematically studying of reinforced soil interface me-chanics characteristics, analyzing the geogrids and soil interaction mechanism and the main influence factors of geogrids drawing mechanical characteristics. Finally, the author analyzed the numerical simulation of reinforced soil drawing test and then use the result to analyze the influence from overburden pressure and drawing speed to the reinforced soil interface. The re-search results and conclusions in this paper are as follows:1. It is systematically introduced the types of geogrids and its application in this paper, summe-rized the currect research both at home and abroad, stated the mechanics and engineering cha-racteristic of geogrid and described the research achievement of reinforced soil interface.2. In this paper, it is present in detail of the geogrids mechanical properties, including the dif-ferent elastic-plastic viscous reflect process of geogrids when under different conditions such as rate drawing, cyclic loading, creep and stress relaxation. It is also put forward variant four element model according to the existing geogrids constitutive model, regarding the linear plas-tic element as nonlinear element, which can be better used to simulate the elastic-plastic during short term stress and flowing deformation during long term stress.3. In this paper, the author studied the reinforced soil interface shear mechanical characteristics after analyzing the results of reinforced soil direct shear test and drawing test. Considering the integrated factors of reinforced soil interface, built the reinforced soil stress model and put forward the tension distribution formula of geogrids. Compared the test results so that to verify the rationality of the formula, and analyzed the drawing force influence parameters.4.In this paper, the author found a suitable calculation method for numerical calculation of reinforced soil finite difference using finite difference program FLAC3D. According to the re-sults of direct shear drawing test to get model parameters, and also simulate the existing test to confirm the feasibility of numerical modeling. Also, the author built ideal model for getting tension distribution as well as analyzed the influence from overburden pressure and drawing speed to the reinforced soil interface. |
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