THE INFLUENCE OF HIGH-PRESSURES ON STRUCTURAL-CHANGES OF SOME MINERALS

An X-ray analysis of some of the most frequently found minerals in nat ural silicate soils that have previously been subjected to pressures o f up to 19 GPa has been performed. The test results have shown that th e increase of pressure on the surface of polycrystal particles of some minerals leads to formation of an amorphous layer. This means that on the mineral particles' surface contacts, where high pressures act, th icker or thinner amorphous layers are formed. These layers, with their various properties, influence changes of engineering properties of na tural soils. The newly formed amorphous particles, under certain condi tions, behave as dispersed colloid systems with directed charged micel les (particles), the system passes from a flocculate to a dispersely d irected state due to which the natural soil starts to move, (settle or slide).