Study On The Differential Settlement Of The Half Filling And Half Digging Roadbed

In recent years, in the process of high-grade highway construction, we often encounter the construction of the cut and fill sub-grade.Because on one-side of the cut and fill sub-grade roadbed is original state but the another is new, so they are qutie different from the the physical mechanics properties of soil, And the time is different, so that the cut and fill sub-grade roadbed is a difficult problem of the project. The most economic and feasible approach to solve the question is to select a correct ambankment structure, to improve the whole and lateral stability between the cut and fill sub-grade roadbed.In the mountain area, geosynthetics (such as geotextile, geogrid and so on) can be used as a treamment in the process of widening the original state on ground. On the one hand, the tensile strength of geosynthetics can reinforce the structural association between the the cut and fill sub-grade roadbed, and make them have enough entirety. On the other hand, geosynthetics can greatly reduce non-uniform settlement of the the cut and fill sub-grade roadbed.In this paper, according to the Xvpu connecting line of Shao-Huai highway, three model experiments of the cut and fill sub-grade roadbed are maked. For simulation concretion settlement and different intension, calcareousness soil is used to simulate original state roadbed. The new roadbed is primed layered by soil. The load device is weight. The settlement and stress of the model experiment are measured by settlement sign and pressure box. The results of experiment show that the result of the geosynthetics is obvious. At last, the action mechanism of geosynthetics in the soil is analyzed systematically.What's more, the paper based on a project example, suggested a rational Bankment structure by using finite element software-ANSYS. For simulation the fact, the life and death element of the software-ANSYS is used to simulate the original stress,then the new roadbed is primed layered. according to diferent environment of the cut and fill sub-grade roadbed on ground (including different height of embankment, different width, and diferent subgrade modulus, diferent Geosynthetics different lays and so on), the paper also analyzed the efects of the geosynthetics which reducing the non-uniform settlement of the cut and fill sub-grade roadbed, the results show that the result of the geosynthetics is obvious to reduce different settlement and stress concentration. The deformation characteristics and setlement rule of the widening embankment structure is analyzed.Then a simple model in load of vehicles is built to simulate the transient state and analyze the difference between reinforced and unreinforced. The results show that the geosynthetics have obvious effect on transient settlement and finally settlement.