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1
Content available Prediction of swell pressure in Neogene clays from Warsaw, based on the swell index
Gawriuczenkow I., Wójcik E.
Geology, Geophysics and Environment
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2018
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Vol. 44, no. 2
219--229
EN
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.
2
Content available Determination of swell index and swelling pressure from suction tests : a case study of Neogene clays from Warsaw (Poland)
Wójcik E., Gawriuczenkow I.
Geological Quarterly
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2017
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Vol. 61, No. 4
738--750
EN
The paper presents the results of swell index, swelling pressure and soil suction tests carried out on Neogene clays from Warsaw, depending on the water content, clay fraction, liquid limit, plasticity index, cation exchange capacity, and content of clay minerals and beidellite. These clays are considered expansive soils in Poland, as they are vulnerable to water content variations in the active zone, which result in their volume change and, in consequence, cause damage of foundations and other construction elements. A number of physical, chemical and mineral properties were determined for these clays. The swelling tests were carried out on samples precompacted in Proctor apparatus, at various initial values of water content. The analyses have shown exponential relation of swell index, swelling pressure and suction versus water content. In addition, the investigated relationship between the suction and swell characteristics of tested clays shows good correlation as a power function between these parameters. In addition, validity of correlations between fitting parameters of obtained relationships and soil index properties, such as clay fraction, liquid limit, plasticity index, cation exchange capacity, and content of clay minerals and beidellite, have been demonstrated. The empirical relations are characterized by high values of the correlation coefficient. A very high fit has also been found for a proposed relationship between the swell index and swelling pressure for tested clays.
3
Content available 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.
4
Content available Evaluation of expansivity of Neogene clays and glacial tills from central Poland on the basis of suction tests
Izdebska-Mucha D., Wójcik E.
Geological Quarterly
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2015
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Vol. 59, No. 3
593--602
EN
This paper presents the characteristics of the expansivity and quantitative prediction of heave of clay soils from Poland based on suction testing. 11 Neogene clays and 6 glacial tills, differing in genesis and plasticity, were analyzed to identify the expansive potential using eight empirical methods. The laboratory studies included measurements of soil-water characteristic curves and soil index properties. Data from water content, volume and suction measurements served to determine the suction compression index Ch and the suction-water content index Dh/Dw of the soils examined. The values of these indices are clearly dependent of the clay fraction content in tested soils. Compared with glacial tills, Neogene clays are expected to exhibit larger changes in volume due to changes in soil suction. Comparative results of the evaluation of expansivity suggest that the chosen classification methodologies provided consistent expansion ratings for glacial tills, while values for Neogene clays vary from low to very high. The lowest expansivity classes have been obtained from evaluation based on soil suction. The McKeen (1992) method has been adopted for calculations of the potential field heave of Neogene clays and glacial tills. In order to provide a rational estimation of expansive soil behavior, specialists should take into consideration the specific site and design features.
5
Content available Expansivity of Neogene clays and glacial tills from Central Poland
Izdebska-Mucha D., Wójcik E.
Geological Quarterly
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2014
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Vol. 58, No. 2
281--290
EN
The revision of classification methodologies for determination of soil expansivity revealed that parameters most frequently used for this purpose are: the liquid limit, plasticity index and swelling parameters which also predominate in older systems of expansive soil assessment, regarded as classical. Seventy-nine soil samples, including Neogene clays and glaciall tills from Central Poland, with a wide range of plasticity were examined for a comparative analysis of soil expansivity with a use of eight empirical methods. The study revealed that Neogene clays are mostly highly and very highly expansive, while glacial tills exhibit low to medium expansivity. Compared to classifications considering soil mineralogy indicators, those correlated solely to Atterberg limits and related parameters were found to overestimate soil expansivity. It is evident that the classifications are in better agreement for glacial tills than for clays. The comparison of mineral composition measured and predicted from swelling tests yielded consistent results.
6
Content available remote 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
7
Content available Overconsolidation and microstructures in Neogene clays from the Warsaw area
Kaczyński R.
Geological Quarterly
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2003
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Vol. 47, No 1
43-54
EN
The main objective of the study was determine the loading history and establish the current state of consolidation of Neogene clays, to study their lithological and microstructural properties, and to define their geological-engineering properties. To accomplish this task, series of laboratory and field tests were performed. The tests were made on clays taken from pits excavated for underground stations and tunnels (A-14-A-15) in Warsaw and from 2 borehole cores taken from the Stegny experimental field. The tests showed that: the clays are historically overconsolidated with an OCR ratio of 25-50 and their current state of preconsolidation is OCR = 2-14; their range of clay microstructures, observed for the first time, are matrix-turbulent and turbulent-laminar and there was a clear anisotropy of quantitative parameters of the pore paces, these parameters varying with depth. The engineering-geological characteristics (physical and mechanical properties) of the clays were assessed. The results of the study can be used directly to evaluate the Neogene clays of the Warsaw area for their suitability as a subsoil for engineering projects and indirectly to accomplish the same with other overconsolidated soils, particularly in regard to the study methodologies applied and described.
8
Content available remote Iły serii poznańskiej jako podłoże składowisk odpadów na przykładzie odsłonięcia w Budach Mszczonowskich
Łuczak-Wilamowska B.
Przegląd Geologiczny
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2002
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Vol. 50, nr 10/2
966-970
EN
Poznań Series formation occurs on the vast territory of Poland. It comprises clays which form a natural barrier sealing underlying geological beds and ground waters from infiltration of contaminants from the sub-surface soils. These sediments are valuable basement soils of landfills. The mineral composition, permeability and cation exchange capacity of quantitatively prevailing coherent soils of this series show that this soil could be a good sealing material and sorbent. However, clays of the Poznań Series show the breccia-type of weathering, are fractured, contain carbonates and sulfates and often are interbedded by loose soils, as it was observed in the outcrop in Budy Mszczonowskie. Therefore, the choice of localisation of a landfill should be preceeded each time by examinations of bottom soils. Often, these soils require applying of simple technical treatment which would improve their parameters to ensure that the landfill be not harmful for the natural environment.
9
Content available Late Carboniferous-Neogene geodynamic evolution and paleogeography of the circum-Carpathian region and adjacent areas
Golonka J., Oszczypko N., Ślączka A.
Annales Societatis Geologorum Poloniae
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2000
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Vol. 70, No. 2
107-136
EN
Twelve time interval maps were constructed which depict the plate tectonic configuration, paleogeography and general lithofacies. The aim of this paper is to provide the geodynamic evolution and position of the major tectonic elements of the area within the global framework. The Hercynian orogeny was concluded with the collision of Gondwana and Laurussia, whereas the Tethys Ocean formed the embayment between the Eurasian and Gondwanian branches of Pangea. The Mesozoic rifting events resulted in the origin of the oceanic type basins like Meliata and Pieniny along the northern margin of the Tethys. Separation of Eurasia from Gondwana resulted in the formation of the Alboran-Ligurian-Pieniny Ocean as a part of the Pangean breakup tectonic system. During the Late Jurassic-Early Cretaceous time, the Outer Carpathian rift had developed. Latest Cretaceous-earliest Paleocene was the time of the closure of the Pieniny Ocean. Adria-Alcapa terranes continued their northward movement during Eocene-Early Miocene time. Their oblique collision with the North European plate led to the development of the accretionary wedge of Outer Carpathians and foreland basin. The formation of the West Carpathian thrusts was completed by the Miocene time. The thrust front was still progressing eastwards in the Eastern Carpathians.
PL
Dla obszaru wokółkarpackiego skonstruowano 12 map przedstawiających konfigurację płyt litosferycznych, paleogeografię i uproszczony rozkład litofacji w okresie od późnego karbonu po neogen. Przedstawiono ewolucję geodynamiczną tego rejonu na tle ruchu płyt i pozycji głównych elementów tektonicznych w globalnym układzie odniesienia. Orogeneza hercyńska zakończyła się kolizją Gondwany i Laurusji, a Ocean Tetydy utworzył zatokę pomiędzy dwom a ramionami Tetydy - Gondwaną i Laurazją. W wyniku mezozoicznych ryftów wzdłuż północnej krawędzi Oceanu Tetydy powstało szereg basenów typu oceanicznego takich jak Meliata i basen pieniński. Ocean alborańsko-liguryjsko-pieniński powstał w wyniku oddzielenia się Gondwany i Laurazji jako fragment tektonicznego sytemu rozpadu Pangei. W okresie od późnej jury do wczesnej kredy rozwinął się ryft Karpat Zewnętrznych. Na przełomie kredy i paleocenu nastąpiło zamknięcie basenu pienińskiego pasa skałkowego. W okresie od eocenu do wczesnego miocenu terany Adri-Alkapy i Karpat Wewnętrznych kontynuowały ruch w kierunku północnym, a ich kolizja z płytą euroazjatycką doprowadziła do powstania pryzmy akrecyjnej Karpat Zewnętrznych i basenu przedgórskiego. Przy końcu miocenu środkowego uformowały się ostatecznie nasunięcia Karpat Zachodnich, podczas gdy w Karpatach Wschodnich ruchy te przetrwały do końca pliocenu.
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