Physical Properties of Clay and Soil Mechanics

On the other hand, a classification of a sorption process on the basis of kinetics data must be conditioned by other chemical properties of the phosphate-soil mixture. For example, if the soil solution is supersaturated initially with respect to some phosphate solid, precipitation is likely to influence the sorption reaction from the beginning. If the soil minerals have a low degree of crystallinity and/or a high degree of hydration, precipitation may be the dominant sorption mechanism even in the rapid stage.In general, low phosphate concentrations and well-crystallized, relatively unhydrated soil minerals tend to favor adsorption as the phosphate reaction mechanism. Other chemical properties, such as the pH value of the soil solution and the kinds of metals in soil clay minerals, exert a quantitative influence on the rapid stage of phosphate sorption, as do such physical properties as temperature. ... 

The book is divided into three parts. At the begirming of Part I, precise and unambiguous definitions of clays and their constituents are given along with clear and succinct explanations. The subsequent discussions of Part I cover the vast and diverse spheres of the science of clays that include their origin and evolution in nature their composition and internal structure their physical and chemical properties and soil mechanics. The analytical techniques for determination of clay constituents are also described in this part. 

ABSTRACT The paper provides the results of experimental study of structural transformation in clay on its deformation promoting changes in its physical and physico-mechanical properties. The processes on the contacts of structural elements are considered, as well as clay structure transformation upon ground consolidation, shear and swelling. It is pointed out that these structural changes should be taken into account when working out soil models for engineering calculations. 

The performed research showed that any residual deformation in clay soils is a result of displacement and redirection of structural elements on contacts. Deformational processes on contacts as a rule are accompanied by the changing number of contacts, their area, and the forces of interaction between structural elements. This results in alteration of strength, deformational, filtrational and other system parameters and in the appearing of anisotropy of physical and mechanical properties. 

Coagulation of clay suspensions forms a coagulation structure specified by the presence of far-and close-distance coagulation contacts between structural elements. They control the physical-mechanical properties of soils, i.e., their liquid or semi-liquid consistency, high porosity (up to 97%), very low strength, as well as thixotropic destruction and restoration. Factors controlling structure formation in clay sediments. 

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