Geosynthetics Reinforced Earth Technology Field Test And Optimize The Inversion Analysis

Geosynthetics is a new type of material used in geotechnical engineering. Along with the successful application of lots of projects in highway, railway and irrigation works, it gets more and more interests. Now, it has been used in every field of civil engineering and takes an important part in the building of infrastructure in our country. With the development of the industry of chemical fiber, and lots of production of geosynthetics which is cheaper and meets the need of projects, the technique of reinforced earth with geosynthetics, instead of the traditional metal material, is widely applied and studied. The paper systematically introduces the history of geosynthetics used in projects, its functions and application, and lays emphasis on the introduction of the application of geosynthetics used in the reinforced earth and the studies at home and abroad in this field.The paper summarizes the applications in different works, introduces two mechanism of the reinforced earth and the methods of design of different reinforced projects, and puts forward my own understandings of these methods.Relying on the trial lot of retaining wall reinforced with geosynthetics in a project at PuXi, Quanzhou, according to the analysis on the measured data of settlement, layered settlement, pore water pressure, lateral displacement and soil pressure, the paper studies the role and mechanism of geosynthetics in the reinforced wall, and the designing method is also discussed. The data show the wall has good status and fair safety factor.Inverse analysis in geotechnical engineering, especially the inverse analysis of optimization, has been widely used. But the existing optimizing methods such as simplex method and Powell method etc, is easy to get into local optimization and can't get the global optimization. Genetic algorithm (GA for short) has global astringency. But standard GA is tend to emerge premature convergence and has poor ability of local tuning. So the paper puts forward improved dual population GA. The parameters of soils are back analyzed with the algorithm according the measured data of the trial lot of the 8-kilomerters-long soft foundation of the Zhang-Zhao expressway. TheIIcalculated result shows the algorithm can avoid emerging premature convergence and improves the ability of local tuning.