| For restrained by its' natural conditions and geographical characteristics, there are a lot of high loess- filled embankments welling up during the highway construction in west area. The issue on settlement -deformation of high loess-filled embankment aroused from above status has been paid more attention to by academic community and engineering technicians. In this dissertation, based on the present research situation and combining the field tests, experiment indoors, centrifuge model test and numerical simulation, the following research work focused on settlement and deformation laws, the influencing factors and its calculating method has been carried out.1. Research on creep characteristics of compacted loess. Firstly, based on a series of 1 -D consolidation test, the characteristics of secondary consolidation on compacted loess were studied and the influence of consolidation pressure, consolidation time, compression index and overload ratio on the coefficient of secondary consolidation were analyzed .The test results indicated that with the change of consolidation pressure, the coefficient of secondary consolidation shows a sound regularity with the variation of stress conditions. In normal consolidation state the coefficient remains approximately a constant value. But when surcharge preloaded, the coefficient will change with the overload ratio and its duration time. Also, under normal consolidation state, there is a significant correlativity between the coefficient of secondary consolidation and compression index and which has little influenced by overload ratio and its duration time. Secondly, the rheological characteristic of compacted loess under high stress has been studied after a series of 1 -D creep test with different degree compaction and water content. As a result, an empirical model of deformation varying with stress and time has been put forward.2. Relying on three typical high loess- filled embankment and through arranging testing component, the varying laws of settlement and earth pressure at transaction, the boundary between filling and digging and among the layers of filling have been measured and analyzed during the stage of construction and after that .At the same time, based on which, the composition of settlement for high loess- filled embankment has been studied.3. In virtue of centrifuge model test, through 10groups test simulating different section form and orographic condition, the laws of settlement -deformation and the wetting characteristic have been researched. Also, the composition of settlement during the stage of loading and holding is analyzed. Compared with the results of field tests and numerical simulation, the research achievement is enriched further more.4. Based on the large common finite element MARC programmer, the influence of settlement on high loess- filled embankment has been discussed in depth from the aspects of the filling height, the form of slope, deformation modulus of embankment and groundsill, modulus ratio and Poisson's ratio. In the meantime, the influence on the composition of settlement suffering from above factors is analyzed. Also, the numerical simulation of the steric effect and the wetting properties on embankment has been worked, the results shows that apart from the foundation settlement, the amount of compressive deformation of embankment itself is a main component of settlement, meantime, which is influenceed by the lateral deformation caused by the height of filling, the Poisson's ration and the form of slope .The steric effect has a great influence on distribution of settlement and stress of soil mass. Wetting will cause localized stress level enhance, consequently which can induce the slope collapse.5. Research on calculating method of creep settlement after construction and compression settlement for loess-high fill embankment itself. Firstly, a revised expression about the modulus of compressibility varying with stress is introduced to layer-wise summation method, which can consider the variation of modulus of compressibility with the increasing filling load on settlement calculation. Secondly, the expression about coefficient of correction K of lateral deformation is brought forward in view of the deformation characteristics of loess-high fill embankment, which can establish tiles between the settlement and the height, the form of slope and filling property. At last, combining the experiment indoors, an applied method of calculating creep settlement after construction for high-stacked embankment has been put forward. Through comparing the results using above method with model experiment and FEM calculation, the reliability of the method is verified.The research from the dissertation crystallized the composition of high loess-filled embankment, analysed and described the settlement -defoemation laws and its characteristics of variation and basicly solved the problem of settlement calculation of high loess-filled embankment, which can offer references to the design and construction for the future.
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