Three Dimensioned Numerical Analysis Of Settlement Of Gravel Pile Composite Foundation

The gravel pile composite foundation has been widely used in construction projects at present, however, relevant theory has not been advanced, especially the settlement computation method for this kind of foundation treatment has fallen far behind the engineering practice. There are two types of settlement computation method for the gravel pile composite foundation, one is the numerical analysis method and the other is the analytic method. The numerical analysis method is of some advantages.Under the base of inheriting former conclusions critically, the application of gravel pile to the treatment of soft roadbed is studied deeply by means of theoretical analysis, centrifugal modeling test, three dimensioned numerical simulation and field test. Numerical simulation is the main work in the paper.The three dimensioned model of gravel pile composite foundation is established according to the SUI-YU-Railway DK61 working section. Model simulates the embankment building process so as to approach what is acrually happening.The numerical simulation analysis tool applies 3D finite difference software. Stress and strain data contrast is done between original subgrade and reinforced subgrade, centrifugal modeling test and filed test.The results indicates, compare with the original subgrade model, that the model of composite foundation increases rigidity of weak subgrade and decreases highly the horizontal settlement and vertical deformation.The strength and stability of the subgrade is improved. Meanwhile, the data of simulation analysis accorded with the filed test.The model of composite foundation can used to forecast the settlement after embankment construction, and the applicability in similar engineering is proved.Therefore what mentioned in this essay still needs verification with more tests and practices.