Prediction of swell pressure in Neogene clays from Warsaw, based on the swell index

The paper presents the results of swell measurements of Neogene clays (Posnanian clay) from the Mazovia region with different grain size distribution and mineral composition. The study was conducted with model soil with initial moisture contents of 15%, 20%, 25% and 30%. The basic physical properties of clays, their mineral composition and swelling parameters such as free swelling index and swelling pressure were determined. Free swell index was correlated to liquid limit, plasticity index, clay content and water content. A very high fit was found for a proposed relationship between the free swell index and swell pressure which offers an inexpensive method of predicting swell pressure in the preliminary stages of site investigation.