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PL
Porównanie dwóch sposobów implementacji anizotropii parametrów wytrzymałościowych ilastych gruntów koluwialno-zwietrzelinowych w modelowaniu uwarunkowań stateczności przykładowego zbocza. Numeryczne modelowanie w nawiązaniu do warunków geologiczno-inżynierskich wzgórza Chełm na granicy Przedgórza oraz Zapadliska Przedkarpackiego. Odwzorowanie anizotropii cech gruntów w obliczeniach MES z zastosowaniem elementów typu interface oraz alternatywnie modelu konstytutywnego jointed rock. Wyniki obliczeń w modelu jointed rock jako wartość wskaźnika stateczności (SF) ok. 20% mniejsza niż w przypadku stosowania elementów typu interface.
EN
Comparison of two implementation methods of the strength parameters anisotropy of clayey soil - weathered colluvium in the modeling of the stability conditions of the exemplary slope. Numerical modeling in reference to the engineering-geological conditions of the Chełm hill at the Carpathian overthrust border. Modelling anisotropy of soil features in FEM calculations, using interface elements and alternatively jointed rock constitutive model. The calculations result of the jointed rock model: the value of safety factor (SF) about 20% lower than in the case of using interface elements.
EN
Results of a series of CRL-type consolidation tests on alluvial deposits form Vistula Delta "Żuławy ”, conducted with diverse load rates are shown. Such approach revealed diversified strain response of tested material. Dividing loading into stages has made increasing of stiffness, which may be applicable on the practice field.
EN
The paper presents the possibility of typical geological maps applications for evaluation of engineering-geological conditions in spatial planning analyses. Appropriate sheets of Detailed Geological Map, Hydrogeology Map and Geo-environmental Map were selected for the considered commune. Genesis and consistency of soils, level of first groundwater table and geodynamic processes should be the base to applying 4-level classification of engineer- ing-geology conditions. The spatial and quantitative analyses were prepared using GIS technology. This procedure was testedfor the case of "urban sprawl” area near Warsaw and let to evaluation scheduled solutions in "The study of the conditions and directions of the spatial management of the commune of Nadarzyn”.
EN
The methodological experience and the results of observation and research have been presented as a part of an expert geological and engineering study for the planned extension of the Henryk Arctowski Polar Station on the coast of King George Island in the South Shetland Islands in Antarctica. The object is realized in an area requiring recognition of specific geodynamic conditions. According to technical requirements coming from the conceptual design project of the station (Kurylowicz and Associates, 2015) it was necessary to adopt a non-standard research program. Engineering and geological characteristics are presented in comparison with geoenvironmental considerations. The assessment of soil and rock properties was carried out in relation to the results of observations and determinations of parameters that could be assessed in the coarse-grained soils and rocks in the area of the designed object.
EN
The research was carried out during Antarctic summer 2015/2016 in the region of Arctowski Polish Polar Station on King George Island (Southern Shetlands) in Admiralty Bay in Antarctica. The scope of hydrochemical studies included selected elements: temperature, pH, dry residue, general slurry, ammonium ion, nitrates, macroelements (chlorides, sulphates, magnesium, bicarbonates and carbonates, sodium, magnesium and calcium) and some microelements. Surface water and groundwater are low mineralized and do not show anthropogenic impact. The results ofphysicochemical tests have been compared with marine water chemistry and few available archival data, which allowed the assessment of water quality and the attempt to identify the groundwater flow direction.
6
Content available Contemporary overview of soil creep phenomenon
EN
Soil creep deformation refers to phenomena which take place in many areas and research in this field of science is rich and constantly developing. The article presents an analysis of the literature on soil creep phenomena. In light of the complexity of the issues involved and the wide variety of perspectives taken, this attempt at systematization seeks to provide a reliable review of current theories and practical approaches concerning creep deformation. The paper deals with subjects such as definition of creep, creep genesis, basic description of soil creep dynamics deformation, estimation of creep capabilities, various fields of creep occurrence, and an introduction to creep modeling. Furthermore, based on this analysis, a new direction for research is proposed.
EN
This study concerns the modeling potential of slopes development with use of numerical stability calculations. Boundary conditions of performed numerical simulations are according to morphological and geological engineering conditions of the flysch slope shaped by weathering and surface mass movements. The multilaminate material model was used in order to imitate shale spatial variation in weathering zones. Furthermore, X-ray computed microtomography technique enabled for visualization of varied condition of shear surface extortion, which cause physical and strength parameters diversity. Calculation outputs show that geometry and location of deformation zones are affected by a model input strength parameter. The presented results confirm utility of numerical modeling as important aspect in the investigation and verification of spatiotemporal slope development cycle.
EN
The selected parameters of the Wartanian and Odranian tills, with relation to their spatial occurrence, grain size distribution, mineralogical composition, matric suction and other physical characteristics, are presented. The assessment of the lithogenesis and stress history on the microstructure is attempted. The comparison of the compression and permeability characteristics from field and laboratory tests has been performed. Laboratory consolidation tests carried out with up to 20MPa vertical stress, revealed two yield stress values, one in the range of a couple hundreds kPa, the other in the range of a couple thousands kPa. Based on those results, the reliability of the soil preconsolidation assessment, with the use of the two different methods is discussed. The aspect of the triaxial strength reduction under the dynamic loading of diverse frequency and amplitude is raised. The research results depict a variety of possible geological-engineering characteristics, under the divergent constraints scenarios, of compression or strength weakening origin. The effects of the specialized research program will widen the possibilities of physio-mechanical and structural characterization of soils for geological-engineering purposes.
EN
Localised landslide activity has been observed in the area of the plateau slope analysed, in the vicinity of the planned Warsaw Southern Ring Road. Using calculation models quantitative and qualitative evaluations of the impact of natural and anthropogenic load factors on slope stability (and hence, safety) are made. The present paper defines six stages of slope stability analysis, leading to an indication of optimum slope design in relation to the development planned. The proposed procedure produces a ranking of factors that affect slope stability. In the engineering geological conditions under consideration, the greatest factors impacting degradation and failure of slope stability are changes in soil strength due to local, periodic yielding and the presence of dynamic loads generated by intensification of road traffic. Calculation models were used to assess the impact of destabilisation factors and to obtain mutual equivalence with 3D-visualisation relations. Based on this methodology, various scenarios dedicated to specific engineering geological conditions can be developed and rapid stability evaluations of changing slope loads can be performed.
EN
Obtaining the reliable values of filtration – consolidation parameters depends on appropriate programming of load velocity. In the paper a critical assessment of the criteria for selecting the load velocity with regard to theoretical model of consolidation under constant rate of load (CRL) was presented. A key element of interpretation is to distinguish three stages of investigation: mobilization of pore pressure, steady phase and unsteady phase. Reliable values of filtration – consolidation parameters are obtained during steady phase, determined on the basis of dimensionless, standardized for CRL tests parameters: the pore pressure and relative time of consolidation CL (continuous loading). In order to assess trends in changes of filtration – consolidation properties of Krakowiec formation clays were chosen for investigations. The tests were performed on undisturbed samples and using soil pastes at different load velocities to propose method to choose appropriate test speed in CL tests.
EN
Proper evaluation of permeability parameters has a crucial signification in multi-scale prediction of consolidation. Drainage path is connected with the time of one-dimensional consolidation in Terzaghi’s theory and numerous later solutions. That is why the evaluation of permeability factor allows to model the settlement’s time of geological layers based on results obtained on a laboratory scale. Numerous tests show a difference of the consolidation degree obtained from one-dimensional strain course and pore pressure distribution. Evaluation of consolidation coefficient cv based on a newly proposed method allows better understanding of the basic reasons of unconventional behaviour of tested soils. Unparallel characteristics of strain and pore pressure distribution show important role of soil’s skeleton creep and its relation to permeability aspects. Solutions proposed by Biot’s theory allow analysing the different velocity of strain and pore pressure distribution. The article presents a new approximated method based on Terzaghi’s theory and evaluation of parameters which are necessary in application of Biot’s one–dimensional solution. These parameters are connected with compressibility and coefficient of permeability. The goal of presented methodological studies is comparison between permeability obtained from application of Terzaghi’s and Biot’s theory. It allows trying to explain physical reasons of differences between applied models and testing results, and improving the methodology of one–dimensional consolidations tests.
EN
Assessment of consolidation character taking permeability factors into account is of crucial meaning for the prognosis of the settlement progress and, indirectly – for determination of soils permeability. Identification of the basic, consolidationruling factor: pore pressure dissipation or creeping of soil skeleton is driving the accuracy of soil behaviour prognosis. It is confirmed by review of variable theoretical solutions. On the basis of the most widespread Terzaghi’s theory, proposals for interpretation of analyses are presented, supported with model characteristics. The analyses should be led regardless of the axial soil deformation progress and pore pressure dissipation. Values of consolidation index should be determined taking the accordance of theoretical and experimental curves into account. Statistical measure of such accordance is one of the proposed assessment criteria. Comparison of consolidation index values established in such way, employing η parameter, allows for determination of permeability or rheological factor dominance, as well as reliability assessment of the results and their usefulness for practical applications and prognosis of bottom behaviour.
PL
Ocena charakteru procesu konsolidacji z uwzględnieniem czynników filtracyjnych ma kluczowe znaczenie dla prognozowania przebiegu osiadań oraz pośrednio określania przepuszczalności gruntów. Identyfikacja podstawowego czynnika rządzącego konsolidacją: rozpraszania ciśnienia porowego lub pełzania szkieletu gruntowego decyduje o trafności prognoz zachowania się gruntu. Potwierdza to przegląd różnorodnych rozwiązań teoretycznych. Na bazie najbardziej rozpowszechnionej teorii Terzaghi’ego przedstawiono propozycje sposobu interpretacji badań na tle charakterystyk modelowych. Analizy powinny być prowadzone niezależnie dla przebiegu odkształcenia osiowego gruntu oraz rozpraszania ciśnienia porowego. Wartości współczynnika konsolidacji należy określać z uwzględnieniem zgodności krzywych doświadczalnych i teoretycznych. Statystyczna miara tej zgodności jest jednym z proponowanych kryteriów oceny. Porównanie tak wyznaczonych wartości współczynnika konsolidacji przy użyciu parametru η pozwala na określenie dominacji czynnika filtracyjnego lub reologicznego oraz ocenę miarodajności wyników i ich przydatności w aplikacjach praktycznych i prognozach zachowania się podłoża.
EN
Soil improvement of the southern ring-road of Gdañsk enabled the obtaining of a rich material collected during observations of the consolidation behavior, on the background of variable geological conditions. These characteristics are essential for carrying out the optimization of the consolidation models and the identification of the consolidation parameters. Comparison of the settlement monitoring results with the predictions of alternative options for consolidation, will enable the practical verification of the participation of distinguished consolidation factors - history of overloads and drain conditions.
PL
Tematyka artykułu dotyczy zagadnienia dystrybucji ciśnienia porowego w badaniach konsolidacji przy stałej prędkości obciążenia (CRL). Badania przeprowadzono na pastach gruntowych sporządzonych z glin zwałowych zlodowacenia Wisły z okolic Susza na Pojezierzu Iławskim. Pasta gruntowa o naturalnym składzie granulometrycznym, lecz zmienionej strukturze (homogenicznej) i wilgotności, przygotowana została tak, aby uzyskać dwufazowy (nasycony wodą) ośrodek gruntowy. Przyjęta metodyka badań umożliwia porównanie otrzymanych wyników z teoretycznym modelem zmian wartości ciśnienia porowego w warunkach liniowego przyrostu naprężenia. W przeprowadzonych badaniach zastosowano różne prędkości obciążenia, co pozwoliło na przedstawienie wpływu tego czynnika na parametry charakteryzujące dystrybucję ciśnienia porowego. Studia nad zmiennością ciśnienia wody w porach w warunkach zróżnicowanych wymuszeń mają istotne znaczenie dla doskonalenia metod oceny parametrów filtracyjno- konsolidacyjnych ośrodka gruntowego
EN
The question of pore pressure distribution during consolidation tests at constant rate of loading (CRL) was presented in the paper. The tests were carried out on soil paste of glacial tills of Wisla glacial period obtained from the area of Susz in Pojezierze Iławskie. The disturbed (homogenous) soil paste of natural particle size distribution was prepared in such a way to obtain biphasic − saturated soil. The chosen method allowed comparing the obtained test results with theoretical model of pore pressure changes during linear incremental loading. Various load rates were used so that the influence of the rate on pore pressure distribution could be presented. The research on variability of pore pressure under various loading conditions is crucial in developing permeability-consolidation parameters investigation methods.
PL
Określanie właściwości izolacyjnych iłów ma kluczowe znaczenie w ocenie efektywności barier geologicznych. Badania konsolidacyjne stanowić mogą pośrednią, ale bardzo efektywną metodę interpretacji parametrów filtracyjnych gruntów słabo przepuszczalnych. Miarodajność oznaczeń zależy od wyboru najbardziej optymalnych dla tych celów metod interpretacji badań konsolidacyjnych. W artykule przeanalizowano przykłady zastosowania zarówno klasycznych, jak i nowych autorskich metod interpretacji badań konsolidacji iłów krakowieckich, obciążanych w systemie IL. Przeprowadzona analiza i porównanie z wynikami badań permeametrycznych umożliwia sformułowanie wskazówek metodycznych dla doboru optymalnej metodyki określania izolacyjności gruntów słabo przepuszczalnych przy zastosowaniu badań konsolidacyjnych.
EN
Determining the properties of clay is essential to evaluate the effectiveness of geological barriers. Consolidation tests can provide an indirect, but very effective method of interpreting the parameters of poorly permeable soil. The reliability of determinations depends on the use of the most optimal methods of interpretation of consolidation tests. The present article is analysing examples, both classic and the new author’s methods of interpretating the result of incremental loading (IL) consolidation tests of the Krakowiec Clays. The analysis and the comparison with the permeametric results, allows formulating methodological guidelines for the selection of the optimum methodology for determining the poorly permeable soil using consolidation tests.
PL
Artykuł przedstawia nowe ujęcie interpretacji badań konsolidacji jednoosiowej, ukierunkowane na określenie optymalnych wartości współczynnika konsolidacji c/v. W obliczeniach opartych na analizie przebiegu odkształcenia jednoosiowego gruntu oraz dystrybucji ciśnienia porowego zastosowano dwie zróżnicowane zależności pomiędzy bezwymiarowym czynnikiem czasu a stopniem konsolidacji. Zaproponowane kryteria pozwalają określić granice quasi-filtracyjnej fazy procesu, optymalną wartość cv oraz wskaźniki zgodności między zachowaniem gruntu a rozwiązaniami teoretycznymi.
EN
The paper presents a new interpretation of laboratory tests for estimating the optimal value of consolidation coefficient c/v. Two different relations between a non-dimensional time factor and a consolidation ratio were used in calculations derived form the analysis of uniaxial soil strain and pore pressure distribution. Based on the adopted criteria it was possible to evaluate a quasi-filtration phase of the process, c/v optimal values and indicate correspondence between experimental and theoretical soil behaviour.
PL
W ramach przygotowywanego w 2011 r. „Programu Polskiej Energetyki Jądrowej” opracowywane są m.in. zagadnienia wyboru lokalizacji elektrowni jądrowej. Prace badawcze oraz analizy bezpieczeństwa obiektu jądrowego w wybranej lokalizacji zostaną przeprowadzone zgodnie z Prawem atomowym i powiązanymi rozporządzeniami oraz wytycznymi Międzynarodowej Agencji Energii Atomowej w Wiedniu (IAEA). Waloryzacja alternatywnych lokalizacji wymaga przeprowadzenia etapowych analiz obejmujących czynniki geologiczne, geofizyczne i hydrogeologiczne udokumentowane na odpowiednim poziomie szczegółowości. Prace te będą służyły wyborowi lokalizacji pierwszej elektrowni jądrowej w Polsce oraz będą mogły być wykorzystane do lokalizacji kolejnych elektrowni w kraju. Wyniki oceny terenu pod lokalizację obiektu jądrowego wraz z wynikami badań i pomiarów zostaną opracowane w formie dokumentacji geologiczno-inżynierskiej i raportu lokalizacyjnego.
EN
Within the 2011 “Project of Polish nuclear power industry” issues concerning the choice of a location for nuclear power plants are discussed. Research and safety analysis of a nuclear power station in a chosen location will be carried out in accordance with the atomic law and other directives set by International Atomic Energy Agency (IAEA). The valorization of alternative locations requires step-by-step, detailed analyses including geological, geophysical and hydrogeological factors. This research will be used for choosing the location of the first nuclear power plant in Poland and it can be applied for future projects. The results of land evaluation in terms of nuclear power plant’s location and the outcome of research and measurements will be described in a engineering-geological documentation and in a report about locations.
PL
Przedstawiono problemy związane z właściwym geologiczno-inżynierskim dokumentowaniem podłoża autostrad. Rozpatrywane są: szczegółowe określanie występowania gruntów organicznych w podłożu, porównanie klasyfikacji gruntów według polskich norm oraz Eurokodu, a także stany naprężenia dla alternatywnych rozwiązań projektowych. Studium analizowanego przypadku wskazuje na konieczność rozszerzenia listy parametrów wyznaczanych w toku badań polowych, które są niezbędne dla projektowania rozwiązań konstrukcyjnych.
EN
The paper presents problems of proper engineering-geological investigation of the highway subsoil. The estimation of organic soil occurrence, comparison of soil classification in Polish standards and Eurocode, evaluation of stress state for alternative design solutions are considered The study on analysed case has indicated that the longer list of parameters must be evaluated during field tests -for highway designing.
EN
The paper presents the application of consolidation tests for coefficient permeability evaluation in cohesive soils. The insulating property of Neogene green clays from overburden of Bełchatów lignite mine are subject to study. These soils are potentially fine material to construct barriers for insulating of contaminations. The results of paste samples tests are compared with behavior of non disturbed structure. The difference of natural and artificial formed structure affect on physical properties and permeability behavior too. The continuous loading consolidation tests let to obtain effective seepage of pore water in short time but head gradient is higher than in natural conditions. It caused contraction effects and may decrease the permeability, when pore water pressure is not dissipate. The consolidation stress and pore water pressure is mainly factor of tests results variability. Differences between permeability of samples formed from paste and natural structure samples may depend on mineral composition and compaction of paste. Consolidation tests let quickly evaluate permeability of cohesive soil with respect for the different factors considered in optional barriers designs.
EN
The paper presents theoretical solutions of the consolidation problem with respect to the different conditions of continuous loading and its application. The author introduces modified consolidation parameters and dimensionless parameters characterizing the course of the consolidation process. Therefore it is possible to calculate the theoretical pore water pressure distribution for various loading procedures in continuous loading (CL) consolidation tests occurring in constant rate loading (CRL), constant rate of strain (CRS) or controlled gradient (CG) tests. The calculation results allow presentation of the attributes that differentate CL consolidation and classical incremental loading (IL) consolidation. A new method of calculation cv (coefficient of consolidation) is proposed using theoretical diagrams of porewater pressure distribution and results of laboratory measure ments during the CL test. A comparative analysis of the methods currently used for cv calculation and the new method is presented here. The cv values estimated by means of method referring only to the seepage factor of consolidation, are usually higher than those based on the strain course. Proper projection of the seep age factor of consolidation makes it possible to shorten the time of consolidation tests in accordance with results of many field observations. The methods described herein can be useful in studying physical conditions of sedimentation, glacial geology, early diagenetic process and applied geology.
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