Microstructural investigation of the effect of minerals on the dispersivity behavior of clays

Document Type : Original Article

Author

Assistant Professor, Faculty of Engineering, University of Qom

Abstract

It goes without saying that, dispersive soil might cause some geotechnical problems, although, in geo-environmental project, they could be used as an excellent contaminant absorbent due to their higher surface area and well exposed clay particles to soil pore fluid. Because of this environmental application, using disperse clay is common in many landfill projects. On the other hand, the dispersivity behavior of soils is known to be a function of clay mineral and concentration of salt in pore fluid. On this base, this paper gives some applicable graphs to estimate the concentration of salt needed to disperse clayey soils with the view of using in geo-environmental project based on the mineral types. The results indicate that, this system provides deep knowledge of salt concentration needed for disperse clayey minerals and mixture of minerals. It is shown that the effect of the clay microstructure is the important factor on the dispersivity behavior of clay minerals.

Keywords


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