EFFECT OF DISJOINING PRESSURE OF HYDRATED FILMS ON THE STRENGTH PROPERTIES OF CLAY

F. S. Karpenko^a,#, V. N. Kutergina and R. G. Kalbergenova

^aSergeev Institute of Environmental Geoscience, Russian Academy of Science, Ulanskii per., 13, bld. 2, Moscow, 101000 Russia
^#E-mail: kafs08@bk.ru

The article considers the effect of disjoining pressure of hydrate films enveloping mineral particles on the strength properties of clay. A method for determining the value of the disjoining pressure of hydrate films is proposed. The regularities of its variation were studied depending on the moisture content in clays on the ba-sis of experimental studies. The reaction to the external stress of adsorption (±) and diffusive (²) layers of hy-drate films is described for different types of structural contacts and the nature of friction at the contacts. The effect of disjoining pressure of hydrate films on the shear stress is shown. The methodology for determining the actual effective strength of clay soils has been developed. This methodology permits us to evaluate not on-ly the external impacts on clay soil, but also the stress at its structural contacts.

Key words: clay soils, microstructure, structural contacts, ±- and ²-layers of hydrate films, disjoining pressure of hydrate films, internal stress of soil, swelling pressure, actual effective stresses

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