Based On Fractal Theory Of Soil Physical And Mechanical Performance Tests

At present,the highway construction of our country has in rapid development stage. But the highway in the amount of rapid increases, the corresponding quality is endless flexibly. Although many scholars respectively from the pavement materials and structure design and the soil subgrade materials and the design of embankment structure have done a lot of research, and also made a lot of research achievements , but the actual service life of highway or shorter than design used greatly service life.As subgrade, soil is the raw material of the foundation soil, but highway as long-term geologic change greatly the product of dispersion and irregularities. This nature of application to soil of traditional Euclidean geometry dies hard to study clear. Fractal theory, as a kind of emerging discipline just can be used to describe the soil this nature. This paper tests are all the soil sample was taken from the surrounding area of Nanning guangxi. From the respectively on soil samples obtained from the physical performance index (the soil liquid plastic limit test, the soil granule analysis test) test and of the soil mechanics performance index (the soil compaction test, the soil CBR strength test) was measured.The paper firstly soil granule analysis according to the results of the tests of various soil samples for the fractal dimension of deriving, then analyzed the content of soil particle in various for the influence of the fractal dimension of soil, got 0.075 mm is less than the particle concentration and the fractal dimension of soil mass between good positive linear correlation with the coarse and fine soil particle ratio has good negative linear correlation; Secondly based on fractal dimension is deduced respectively the highway soil test of the evaluation rules of soil particle gradation index non-uniform coefficient and coefficient of variation of the equation of infrastructure, the particles by double index evaluation index unified arrived but index fractal dimension, simplified the above the complexity and improve the evaluation of the accuracy of the evaluation. This paper introduced the all the compaction test compaction curve theory and standard compaction test curve of the scope of moisture content than it more extensive. By introducing the pressure is the four parameters, S_max(maximum curve of saturation parameters), W_max(the biggest water content parameters) and a (compaction curve can compaction regional index parameters), b (the compaction test curve shape parameter) can compare the comprehensive and profound understanding of the curve of the compaction test. And through this four parameters were studied with the soil liquid plastic limit index and the soil granule analysis test between physical indexes established a connection. Finally, analyzed the soil and the viscosity of soil particle push for the soil strength index proportion and resilience modulus value CBR the influence.