The Tensile Property And Forming Optimization Research Of Plastic Geogrid

Plastic geogrid is a kind of special geosynthetic material. It is widely used as reinforcing material in the composite material to strengthen and protect the project in the areas such as water conservancy, highway railway, coal mine and building. Geogrids can raise the subgrade strength by reducing the uneven subsidence. It possesseses the proprieties of light weight, high strength, anti-aging, anti-deformation, good toughness, alkali-resisting, acid-resisting, so it is widely used in the poor environment. China has begun to research on plastic geogrid in recent years, but the research direction is in favor of the engineering application, as for the production, such as the formula and technology, is paid on less attention. The research of this aspect is just on the initial stage. Based on the research status of geogrid in China, this paper performs experiments to research the technology of geogrid production and then simulate the forming process of the experiment sample with ABAQUS software, so as to acquire the best production process.This paper first discusses about the definition, basic types, properties, requirement on drawing process equipment and process conditions of geogrid. It summarizes the efforts and research result on properties of high polymer and its constitutive model from scholars at home and abroad and explains the tensile reinforcement mechanism of polymer materials. It also describes the forming process of geogrid detailedly.Especially, the necking character is analyzed and the forming and propagation condition is summarized.The experiment focuses on the tensile properties of plastic geogrid. A single variable experiment and orthogonal experiment are taken to analyze the affection of temperature, tensile velocity and draw ratio to the tensile strength and elongation at break of geogrid. Finally the best production process parameters will be gotten.The related issues about the ABAQUS simulation, such as the choice of model, determination of material property and boundary conditions, settings of analysis steps, meshing and job submission, are also elaborated detailed. The uniaxial tensile process of the sample used in the experiment and the geogrid in production are simulated. The feasibility and accuracy of hyperelastic constitutive model is confirmed. At the same time, the performance of geogrids with different hole patterns are simulated and a optimized hole pattern is proposed. At last, the biaxial tension process of geogrid is simulated and it’s performance is analyzed.