滑坡滑带土微结构的定量研究

土质滑坡在滑动带形成之前，其矿物颗粒的分布是原生状的，带有很大的随机性。在应力的作用下，矿物颗粒的排列方向不断地调整并逐渐定向排列，直到滑坡失稳定前夕，这种定向排列已经达到相当的程度。也就是说，滑带土矿物颗粒的定向排列与滑坡的发展阶段是相互对应的。在过去的研究中，人们一直无法得到滑带土的微结构定量的特征值。本文从分形几何学的角度出发，认为滑带土的微结构具有分形(Fractal)的特点，因此，可以用分维(Fractal demention)作为一种特征值来描述土的矿物颗粒的分布状态。而后，又从统计物理学和信息论角度论述了滑带土矿物颗粒的排列熵，将其作为另一种微结构的特征值。它表示了滑带土的微结构从混沌到有序的变化程度。本文在野外工作和室内实验的基础上，对滑带土样品和实验样品的薄片利用计算机微结构图象处理系统进行分析计算。得出了土的分形、熵分别与压力、剪力、时间和水的作用的关系；研究了新滑坡和处于发育期滑坡的滑带土的分形、排列熵的分布情况；最后，还在利用分形和熵在确定滑坡规模、发育阶段、以及应力场反演等方面做了尝试。
工业羊毛毡
The distribution about mineral particles of soil landslide is protogenous and randombefore the creation of sliding area. Under the action, of stress field, the arrangement ofmineral particles is increasingly regulated, suggesting a new directed arrangementwhich comes up to a rather high lrvel before the stability lost of landslide. The direc-tional arrangement of mineral particles at sliding surface soil is correspondent with thedevelopment process of landslide. Viewed from this aspect, we get the hang of under-standing better of formation mechanism and developing regularity on landslide,providing some significant means and valuable information for landslide harness andits forecasting.Soil texture has no other characteristics so that a large barrier of the quantitativestudy, is encountered. As recognized by differential geometry, soil microstructure ischaracterized by fractal. Therefore, the distributional situation of soil particles can bedescribed by fractal demension. The arrangement entropy, a measured criteria fordirectional arrangement degree of mineral particles, stands for the development of soilmicrostructure from chaos into order.By the use of computer image system to analyse and to computerize almost 300microphotographs, it comes to the conclusions that the relaton among fractal dimen-sion, arrangement entropy and force is obtained and that the influence of waterprocess on fractal dimension and arrangement entropy is also ascertained at the sametime. The distributional situation of fractal dimension and of arrangement entropy atthe sliding surface soil has been carried out during new landslide and growinglandslide occurrence. It has been found that they distributed regularly along slidingorientation. Finally, an attempt has been done in the domain of using fractal andentropy to determine the landslide demension, developing stages and counterevolutionof stress field.