A 2-DIMENSIONAL FUZZY RANDOM MODEL OF SOIL PORE STRUCTURE

A new conceptual model for soil pore-solid structure is formalized. So il pore-solid structure is proposed to comprise spatially abutting ele ments each with a value which is its membership to the fuzzy set ''por e,'' termed porosity. These values have a range between zero (all soli d) and unity (all pore). Images are used to represent structures in wh ich the elements are pixels and the value of each is a porosity. Two-d imensional random fields are generated by allocating each pixel a poro sity by independently sampling a statistical distribution. These rando m fields are reorganized into other pore-solid structural types by sel ecting parent points which have a specified local region of influence. Pixels of larger or smaller porosity are aggregated about the parent points and within the region of interest by controlled swapping of pix els in the image. This creates local regions of homogeneity within the random field. This is similar to the process known as simulated annea ling. The resulting structures are characterized using one-and two-dim ensional variograms and functions describing their connectivity. A var iety of examples of structures created by the model is presented and c ompared. Extension to three dimensions presents no theoretical difficu lties and is currently under development.