Wyniki wyszukiwania - BazTech

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Identyfikacja składu mineralnego i pęcznienia gruntów spoistych na podstawie współczynnika swobodnego pęcznienia

Izdebska-Mucha D., Wójcik E.

Biuletyn Państwowego Instytutu Geologicznego

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2016

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nr 466

77--85

EN

The paper presents the results of free swell measurements of Neogene clays and model clay mixtures composed of Wyoming bentonite and Sedlec kaolinite. Modified free swell index (MFSI) as well as free swell ratio (FSR) were determined and analyzed with respect to pore fluid chemistry, mineral composition and clay content. The FSR, defined as the ratio of the equilibrium sediment volume of 10-g oven dried soil in 0.0025% NaCl solution to that in kerosene, has proved to provide only a rough prediction of clay mineralogy in natural soils.

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Zmiany mikrostrukturalne past gruntowych pod wpływem ciśnienia ssania

Wójcik E., Trzciński J., Łądkiewicz K.

Przegląd Geologiczny

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2013

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Vol. 61, nr 1

74–-82

EN

This paper presents an issue of microstructural changes in clay soils during the water loss due to increase of suction pressure. The change of microstructure affects the geological engineering properties of soils causes problems with the foundation of buildings. The volumetric changes of cohesive soils, containing significant amounts of clay minerals from the smectite group, are caused by a variable water content in soil. The phenomenon of the moisture change significantly alters the geological engineering properties of these soils as a result of shrinking and swelling. This paper aims at presenting the microstructural changes in remoulded specimens of Neogene clays caused by loss of moisture due to suction pressure. The scientific examination involved quantitative analyses of the microstructure using scanning electron microscopy (SEM) to study pore space details of remoulded specimens. Tested samples from selected levels of the Neogene clays (Poznan Series) were collected from the Warsaw-Stegny area. Samples were taken from a research polygon for these clay soils. The basic geological engineering properties of clay soils and remoulded specimens have been examined after being prepared according to strictly defined procedures. Through successive stages of the suction pressure (from 50 to 1600 kPa), the samples underwent the process of loss of moisture. Application of a novel method of sample preparation procedure for remoulded specimens allowed examining structurally homogeneous soils and obtaining results without an effect of material anisotropy. The qualitative and quantitative analysis of soil microstructures were performed using SEM and STIMAN software for quantitative images processing. The analysis allowed determination of the number of geometric and morphometric parameters of the microstructure with high accuracy. Based on this study, significant qualitative and quantitative changes in loss of moisture due to suction pressure in the process of remoulded specimens were noted along with changes in the microstructure and pore space of clay soils. The obtained results showed the effect of successive stages of "closing" of the structure of cohesive soils. Microstructural changes have a significant influence on the values of clay soil properties during the shrinkage and swelling process, which are caused by changes in the water content.

3

Porównanie właściwości ekspansywnych iłów neogeńskich z Mazowsza

Gawriuczenkow I., Wójcik E.

Przegląd Geologiczny

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2013

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Vol. 61, nr 4

243--247

EN

Development of building projects in the Mazovia region causes the risk of their location on the soils of specific expansive properties. These properties, expressed as swelling or shrinkage, are a serious engineering problem. Many methods are used for the evaluation ofexpansiveness; both direct and indirect test methods are used. Tests were performed on clays from the areas of Warsaw, Dobre near Mińsk Mazowiecki and Mszczonów. Comparative analysis of expansive properties of Neogene clays is based on the results of laboratory tests of mineral composition, grain size distribution, moisture content, free swelling and swelling pressure. The tests have shown that the expansive properties ofclays from the Mazowsze region can have extremely high values, which causes the needfor individual determination of potential expan-siveness for different types of clays, depending on moisture content, swelling pressure and chemistry of the environment.

4

Właściwości sorpcyjne iłów neogeńskich i możliwości ich wykorzystania do usuwania jonów metali ciężkich ze ścieków

Kyzioł-Komosińska J., Rosik-Dulewska C., Kocela A.

Przemysł Chemiczny

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2008

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T. 87, nr 5

501-505

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Uwarunkowania stosowalności iłów jako izolacyjnych barier geologicznych na przykładzie iłów ze złoża w Budach Mszczonowskich

Drągowski A., Łuczak-Wilamowska B.

Przegląd Geologiczny

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2005

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Vol. 53, nr 8

687-690

EN

Storage is one of the most widely applied methods of neutralisation of wastes, prevailing over thermal, chemical and biological treatment. Waste disposal site must be harm-less for the natural environment and for the human’s life and health. Its sealing must be reliable. However, the recently used synthetic liners are not sufficient. Experiments showed that the proper protection of the natural environment against the interaction with wastes may be achieved by using naturally occurring grounds, or by composing artificial mineral sealing barriers. The deposits to be used a as a barrier must have specific characteristics required by the binding regulations. On the example of the clays from the pit in Budy Mszczonowskie, the paper presents the range of investigations needed to evaluate applicability of the Neogene expansive soils as the sealing barriers.