Parametry geotechniczne czestochowskich ilów rudonośnych z rejonu Konopisk (SW obrzezenie Czestochowy)

In the vicinity oj the Konopiska municipality (SW margin of Czestochowa) ore-bearing clays have been deposited These formations, only locally covered by younger sediments, constitute direct foundation subsoil, so their geotechnical parameters may conditionate founding possibility of various structures. The paper presents results of a series of experiments (conducted accordingly to PN-B-04481: 1988) dedicated to estimation of the geological-engineering properties of these clays in terms of the possibility of their use as a founding ground or a material to build earth structures. It has been learned that the tested soils conta in high amounts of clayey fraction, occur in semi-solid state and show relatively high shear-strength parameters. Their natural water content is close to the optimum one (18-20%), at which a clear peak of the dry density (about 1.7 Mg/m3) is noted. Low colloidal activity proves that they are prone to expansion. A ll these properties indicate that they can constitute a competent subsoil for typical structures of the first or second geotechnical category, unless obviously the ultimate and serviceability limit states are checked and satisfied for the particular geotechnical case.