Study And Analysis On Settlement Of High Fill Subgrade In Jilin Province

In recent years, with the process of highway extending in China, there will be more and more high fill subgrade. Because of the greatly different geological question met in the course of construction of highway in our country, the experience accumulated can't be simply used in the country. One of the common faults is the deformation and damage of the high fill subgrade. The causes are very complex. It relates not only to the density of the filled soil for the roadbed,but also to the nature of roadbed filling materials, side-slope gradient, foundation nature, hydrology condition, roadbed pressing machine, design standard and construction method. In the projects, the deformation and damage of the high fill subgrade is mainly presented as cracks on the filled-soli for the embankment, sliding of the roadbed, collapse of the side slope and the related roadbed structure damage,whole or partial settlement of the roadbed etc. Once the high fill subgrade is deformed and damaged, it is very difficult to repair. Therefore, high attention must be paid to it. In order to avoid oversized settlement and deformation, further research on the settlement and deformation of high fill subgrade is much more meaningful.Therefore, to hig fill subgrade that Jilin province appeared, it is necessary to launch the observation on settlement and the research for settlement law of the high fill subgrade. By means of arranging and analyzing the measured data of the settlement of the high fill subgrade, the late settlement can be forecasted as well as the law of settlement and deform of the can be generalized, and for reasons given above, it can instruct further optimization design, improve relevant construction crafts, and offer directly scientific basis for decision of construction of the highway.Access to consult a large number of relevant information, this paper summary the history and present situation of the high fill subgrade settlement problems, review of the theoretical analysis of foundation settlement and common practical methods of calculating methods, discussed the problems and deficiencies of the high fill subgrade settlement mechanism and the traditional method. For these deficiencies, this paper analysis of high fill subgrade settlement mechanism based on the laboratory test results, and combined with finite element analysis software ANSYS, used for D-P geomaterials constitutive model. This paper analysis of high fill subgrade settlement problems, make plane strain elastic-plastic numerical simulation. Utilizing the flexibility of numerical simulation, in this paper, the effect of the factors including filling height, filling slope, filling material, the depth of foundation treatment, compaction of subgrade on the settlement are studied. Monitoring the variety of the height of filling of three typical test roads selected in Jilin province. Their settlements are recorded. The variety rule is studied. The results of the numerical simulation are verified by the monitor results. Comparing the results of ANSYS numerical simulation and monitoring of test road, it find that the both results are basically same. The errors are less than 10% between forecast settlements and real settlements. We can say that the forecast of the numerical simulation consistent with the real engineering. The measures that can be adopted to decrease settlements are proposed by simulation of various effect factors.