两种土壤粒径分形模型的对比研究

本文从两种土壤粒径分布分形模型的推导入手,分析得出的土颗粒质量-粒径分布分形模型(模型二)仅是在土颗粒密度相同的假定条件下对土颗粒数量-粒径分布分形模型(模型一)的近似替代,并以某滑坡滑带土为例,分别运用这两种模型对该滑带土样进行粒度分形特征的试验研究,结果表明:由模型二计算的粒径分布分维数和相关系数均比模型一的小,其误差产生的原因是土颗粒密度由于矿物成分的不同而存在差异;但是模型二的计算结果可以较好地反映试样的分形特征,其原因是各粒组的各种矿物的相对含量相差不大,土颗粒的平均密度近似相等,假定条件适应性较好。

Contrastive Research on Two Kinds of Soil Particle Size Fractal Models

Starting from the derivation of two kinds of the soil particle size fractal models,this paper shows that the model of grain quality-particle size fractal model(Model 2) is just a close substitute of grain quantity-particle size fractal model(Model 1) under the assumption of the same soil particle density.The slide soil of a landslide is taken as an example and the two models are used to research the fractal characteristics of soil sample granularity.The results show that,for Model 2,the fractal dimension of grains distribution and the related coefficient are smaller than those for Model 1.The cause of the error lies in the difference of soil particle density because of the difference of the mineral composition.But the result of Model 2 can better reflect the fractal characteristics of soil sample,because the different granularity groups have the similar percent of mineral composition,the average density of grain is similar and the flexibility of assumption is good.