Determining the Suction Capacity of Compacted Clays with Fuzzy-Set Theory

Abstract

Abstract Water suction capacity is an important parameter affecting soil's swelling properties and volumetric change. The water suction capacity is determined through timeconsuming laboratory experiments. However, this has random errors due to the heterogeneous and anisotropic structure of the soil sample together with the error caused by the operator made the experiment. Solving such an estimation problem including error can be easily achieved using fuzzy-set theory. In this study, we use fuzzy-set theory to predict the suction capacity of compacted clayey soils. For this reason, the engineering properties of clayey soil (plasticity index, dry density, initial water content, and suction capacity) are partitioned into fuzzy subsets, and fuzzy rules are formed. Later, a computer program in the Fortran language is written to estimate the suction capacity of compacted clayey soil from these properties. It is shown that there is a good similarity between the results of the tests and the proposed fuzzy logic model.