Experimental Study On Properties Of Lime-Stabilized Loess Embankment

It is that the loessland has a wide range,different genesis styles,a large thickness variation and a complicated compressivility changement in china.Many railway routes must travelling loessland,but It was short of reaserch on the characteristic of loessial settlement in the construction of railway especially high-quality railway ago. To ensure roadbed's rigidity, intensity and post-completion can satisfy high- quality railway's requiremen,it is necessary to develop analytical technique based on reasonable theory to offer useful parameters and experiences in design for the similarity.The high speed running of train needs smooth and stable foundation of track undersurface.It means that a high quality of stability for the settlement is needed for new built high- quality railway.Especially in the loessland, to ensure the train safety,stability and passenger comfort in tune with the design speed once open to traffic,Xi-Yan railway through loessland adopts a new technique to improve loess's property.That is to say,we incorporate a certain proportional lime in the loess to improve the loess roadbed's rigidity, intensity and control the post- completion.The paper based on the loess roadbed of Xi-Yan railway,has a research of the machanics characteristic of improved loess and the application of FEM in the construction of engineering,there are several main works in the paper.Firstly, we choose representativeness loess samples, incorporate a certain proportional (3%,6%,9%)lime in the loess samples.Then,do the unconfined compression strength test, triaxial compression test, direct shear test, compaction test, K₃₀ for coefficient of subgrade reaction test, permeability test, limit water content test and other testes.Through these tests,we can get the mechanics characteristic of improved loess,Take as filler. Secondly,the thesis introduces the finite element method(FEM) to compute different changement of the roadbed's internal force and settlement in different construction sequences and the stadge when trains are running.At last,the paper make a contrast and analysis on the behavior of the roadbed structural mechanics between the improved loesses (3%,6%,9%).Thus it can be seen that the improved loess roadbed(3%) has a less settlement and internal force,Which satisfy high-quality railway's requirement.So, The method may supply a datum and technique for the design and construction of high- quality railway and reference to the similarity.it is definite value in practice.