The Study On The Stability And Settlement Deformation Of High Fill Subgrade For Changan Comprehensive Test Track

With the fast development of automotive industry in world, the construction of test track has been entered a new era. So the construction standards of test track become more and more higher, the requirements of subgrade of testing ground also become more and more stricktly. The comprehensive test track of Changan in Chongqing will be the first one in western, due to the special requirements of subgrade and packing on the test track, and without enough mature experiences and technology because of the test track is built at the first time, therefore, it's necessary to study the subgrade packing of the test track and analysis the settlement and stability of embankment.According to the research date of embankment settlement of test track at home and abroad, based on the engineering of Changan comprehensive test track which is going to be built, to study the stability and the settlement of subgrade with experimental. According to the research date of embankment settlement of test track at home and abroad, based on the engineering of Changan comprehensive test track which is going to be built, to study the stability and the settlement of subgrade with experimental study and theoretical analysis, the main contents are as follows:(1)The basic physical properties parameters of subgrade packing which is got in field are confirmed with the geotechnical experiment such as moisture content tests,compressive tests,direct shear tests,triaxial tests,permeability tests and compaction tests; the deformation scheme of subgrade packing is designed, the deformation indexes are determined by the cure of springback deformation and the second deformation for to research the compaction characteristic of subgrade filling.(2) Based on the consolidation theory, the deformation of embankment settlement is calculated, and according to the requirements of construction,the time that settlement after constuction for three weeks achieve to control aim is to be predicted.(3) Four typical subgrade cross-section is studied with centrifugal model test,the settlement deformation of model is obtained, while the settlement deformation of field subgrade is analyzed, the relationship between the height of subgrade and the deformation of subgrade is researched, the results show that the strength and stability of subgrade is improved effectively and the settlement deformation is declined when the subgrade is replaced with lime soil.(4) The influence of the filling height of embankment on settlement is analyzed with numerical simulation for settlement deformation of different subgrade cross-section by finite element software, then the distribution laws of internal settlement of subgrade and the stability is obtained. The maximum horizontal displacement and settlement deformation of three filling ways are obtained with finite element for different replacement method of the bend in high-speed circular road.The stability and settlement of subgrade is analyzed for the physical properties parameters of subgrade filling of Changan comprehensive test track which can offer technical support and guarantee for the design and construction of the test track, meanwhile, which can also accumulate valuable experience and technologic information for future test track, and lay foundation for promoting the technological progress of test track in China.