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Preliminary back-analysis of the height of mud brick fortifications based on geoarchaeological data at Tell el-Retaba site in Egypt

Trzciński J., Zaremba M., Rzepka S., Bogusz W., Godlewski T., Szczepański T.

Studia Quaternaria

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2017

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Vol. 34, Nr 2

99--108

EN

The Tell el-Retaba archaeological site is located at Wadi Tumilat, a shallow valley running from the Nile Delta to the Bitter Lakes. In ancient times, a route connecting Egypt with Syria-Palestine ran across the site. In the 13th century BC, during the rule of Ramesses II, a fortress surrounded by “Wall 1” was erected and in times of Ramesses III in the 12th century BC, a larger fortress surrounded by “Wall 2” and “Wall 3” was constructed. Using the finite element method (FEM) and ZSoil 2D&3D software, the wall heights were modelled and their soil-structure interaction was analysed. Strength of the wall depended on size and strength of bricks and mortar, brickwork, wall shape and foundation. Ancient builders using mud bricks must have known from practical experience the essentials of a wall construction, in which the height to width ratio was at 1.75 to 1.85. Moreover, they must have related the engineering properties of the material with the height of the construction and its purpose. The width to height ratio must have been used and related by ancient Egyptians to the ground resistance. Modelling has shown that, at wall width of 5 m, the foundation would have lost its stability at wall height of 13–14 m and bricks from the lower part of the wall would be destroyed. According to the undertaken assumptions, in order to retain stability, the wall height must have been limited to about 8–9 m.

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Holocene lake sediments as a source of building material in ancient Egypt; archeometric evidence from Wadi Tumilat (Nile Delta)

Zaremba M., Trzciński J., Welc F.

Studia Quaternaria

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2017

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Vol. 34, Nr 2

109--118

EN

The Tell el-Retaba archaeological site is located in the middle part of Wadi Tumilat, which extends along the north-eastern margin of the Nile Delta. It contains fragments of fortified and domestic objects of the ancient fortress and other constructions built of mud bricks. The establishment and functioning of the fortress is dated at the times of the reign of two great pharaohs, Ramesses II and Ramesses III (13th and 12th centuries BC). The grain size composition of the sediments used for mud brick production had significant influence on their physical and mechanical properties, which was used by the ancient Egyptians for the improvement of bricks. The finest fractions, clay and silt, which generally comprise clay minerals and organic matter played a significant role. These components significantly influenced the mud brick properties and resulted in a structural cohesion of the material. The second important component of mud bricks were coarse fractions – sand and gravel. The source of material used for brick production were the natural sediments located in the vicinity of the fortress, i.e. the Holocene lake clay and the Pleistocene gravel and sand of the gezira formation, deposited by a braided river. Clay sediments have a variable lithology as can be deduced from grain size composition of mud bricks and their properties. This variability was caused by a variable regime of the Nile, which supplied material to the lake basin. Geological studies were used to recognize ancient environment and morphology of the area, and to find clay, sand and gravel open-pits that existed in the area. The fortress site was selected optimally in relation to the landscape morphology and close vicinity of the source of basic material and water used for mud brick production. The area around the fortress was substantially transformed by humans due to settlement.

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Preliminary report on engineering properties and environmental resistance of ancient mud bricks from Tell el-Retaba archaeological site in the Nile delta

Trzciński J., Zaremba M., Rzepka S., Welc F., Szczepański T.

Studia Quaternaria

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2016

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Vol. 33, Nr 1

47--56

EN

The archaeological site Tell el-Retaba in north-eastern Egypt, about 35 km to the west of Ismailia city, is located in the middle of Wadi Tumilat, a shallow valley running from the Nile Delta to the Bitter Lakes, along which flows the Suez Canal. In ancient times the valley was a route between Egypt and Syro-Palestine, strongly fortified in the New Kingdom times (16th–11th century BC). Mud bricks were analyzed from two parts of the Wall 1 (core of grey-brown bricks and inner extension of green bricks) in a fortress which existed during the Ramesses II times. Grain-size composition of the studied bricks was almost identical in both parts of the wall, suggesting the same source material for a production of brick. However, significant differences were observed in physical and mechanical properties (uniaxial compressive strength) in both types of bricks. Bricks from the core had lower bulk density, higher porosity and soak faster, whereas their resistance parameters were much lower than those of the bricks from the inner extension. The reason for such large differences in brick properties was a technology of their production, particularly proportion of components, water volume added during brick formation or density degree. Brick preparation and in consequence, physical-mechanical properties had direct influence on preservation of defensive structures during environmental changes related to changes of groundwater and surface water levels or of precipitation. Ancient Egyptians responsible for construction works in mud brick structures of the fortress must have had good knowledge and experience. This could be observed particularly for the heaviest and most important construction element that is the defensive wall, founded on well-densified deposits. It was also testified by higher resistance of green bricks from the inner extensions, which probably originated slightly later and were intended to reinforce a weaker core built of grey-brown bricks.

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Stress-strain behaviour analysis of Middle Polish glacial tills from Warsaw (Poland) based on the interpretation of advanced field and laboratory tests

Bąkowska A., Dobak P., Gawriuczenkow I., Kiełbasiński K., Szczepański T., Trzciński J., Wójcik E., Zawrzykraj P.

Acta Geologica Polonica

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2016

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Vol. 66, no. 3

561--585

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.

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Applicability of ground penetrating radar on desert archaeological sites: a case study from the Saqqara necropolis in Egypt

Welc F, Mieszkowski R., Kowalczyk S., Trzciński J.

Studia Quaternaria

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2014

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Vol. 31, Nr 2

133--141

EN

This paper presents the preliminary results of ground penetrating radar sounding applied at the desert archaeological site in Saqqara (Egypt). The survey was carried out in 2012 within a project realized by Institute of Archaeology, Cardinal Stefan Wyszyński University in Warsaw and the Faculty of Geology, University of Warsaw. One of the key aims of the research was testing the application of ground penetrating radar to non-invasive surveys of desert archaeological sites. Radargrams obtained for area of so called the Dry Moat channel surrounding the Step Pyramid complex have shown the geological structure of its filling. It comprises among others debris-sand conglomerate of diluval origin characterized by a significant content of the clay fraction and clay minerals. Such lithological content strongly attenuate the propagation of EM waves, restricting the depth range of the GPR survey. The conducted geophysical prospection west to the Step Pyramid in Saqqara has confirmed the high applicability of the GPR method in non-invasive studies of vast architectural structures, such as the monumental ditch surrounding the Step Pyramid known as the Dry Moat. It should summarised that high horizontal resolution obtained during GPR survey is a result of local geological structure of the searched area, i.e. strong lithological contrast of the sediments filling the Dry Moat, which, depending on their mineralogical composition.

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Geophysical survey (GPR) in West Saqqara (Egypt) preliminary remarks

Welc F, Trzciński J., Kowalczyk S., Mieszkowski R.

Studia Quaternaria

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2013

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Vol. 30, Nr 2

99--108

EN

Geophysical investigations in West Saqqara area were part of the archaeological field work of the Polish Egyptian archaeological mission during the campaign in 2012. The main purpose of geophysical prospection using the ground-penetrating radar (GPR) was to deter mine the location of potential underground sepulchral structures. During the GPR survey, optimal depth penetration was achieved due to dry rocks and monolithic structure of the lime stone plateau on which the ancient cemetery was located. Using antenna of 100 MHz, the depth of penetration was up to 45 m and with antenna of 250 MHz, up to 15 meters. Three main groups of archaeological structures were identified: sarcophagi and mummies, burial shafts; mobile objects (solid rock blocks as fragments of tombs). One of the main goal of the GPR survey was to track the route of the western part of the Dry Moat, expressed by a wide and shallow depression spreading to -wards north-south. The results of geo physical investigations suggest that Saqqara plateau is an ideal site for using GPR surveying technology.

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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.

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Właściwości mikrostrukturalne aluwialnych gruntów ilastych długotrwale zanieczyszczonych paliwami ropopochodnymi

Izdebska-Mucha D., Trzciński J.

Biuletyn Państwowego Instytutu Geologicznego

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2011

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nr 446 (2)

469--476

PL

W artykule przedstawiono wyniki badań mikrostruktury aluwialnych gruntów ilastych z terenu lotniska wojskowego w Królewie Malborskim, poddanych wieloletniemu zanieczyszczeniu in situ substancjami ropopochodnymi. Dokonano porównawczej analizy mikrostruktury gruntu czystego (NS) i zanieczyszczonego (SR). Badania przeprowadzono z zastosowaniem skaningowego mikroskopu elektronowego (SEM) oraz programu STIMAN do ilościowej analizy zdjęć z SEM. Grunt NS charakteryzuje się ukierunkowaną mikrostrukturą turbulentną (mikrostrukturą fluidalną), zagregowaną i ciasno upakowaną masą ilastą oraz dominującymi kontaktami typu płaszczyzna-płaszczyzna (F-F) pomiędzy cząstkami i mikroagregatami. Natomiast grunt SR charakteryzuje się mikrostrukturą matrycową, występowaniem stref o luźnym upakowaniu i słabszym zagregowaniu masy ilastej oraz dominacją kontaktów typu płaszczyzna-krawędź (F-E). W gruncie zanieczyszczonym stwierdzono zmianę rozkładu wielkości i geometrii porów wyrażającą się wzrostem: porowatości, liczby porów, całkowitej i średniej powierzchni porów, całkowitego, średniego i minimalnego obwodu porów, średniej średnicy porów, liczby mezoporów, porów izometrycznych i szczelinowatych oraz spadkiem zawartości mikroporów i porów anizometrycznych.

EN

The paper presents the results of the research on alluvial clay soils from military airport in Królewie Malborskie, polluted with hydrocarbons for a long period of time. Comparative microstructure analysis of polluted samples (SR) and non polluted reference samples (NS) has been conducted. The research was carried out using Scanning Electron Microscope (SEM) and STIMAN software for a quantitative analysis based on SEM micrographs. NS soil is characterized by oriented, turbulent microstructure (fluidal microstructure) and aggregated, tightly packed clay mass. Face-to-face contacts (F-F) dominate between particles and microaggregates. SR soil is characterized by matrix microstructure less aggregated, with some zones of a loosely packed clay mass. Face-to-edge contacts (F-E) dominate between structural elements. It was found that the pore size distribution and pore geometry changed in SR soil. The increase of the following parameters was observed: porosity, pores number, total and average pores area, total, average and minimum pores perimeter, the average pores diameter, the number of mesopores, fissure and isometric pores; but the content of micropores and anisometric pores decreased.

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Właściwości geologiczno-inżynierskie i mikrostrukturalne glin lodowcowych zanieczyszczonych substancjami ropopochodnymi

Izdebska-Mucha D., Szyszko C., Trzciński J.

Biuletyn Państwowego Instytutu Geologicznego

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2011

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nr 446 (2)

459--467

PL

Badania przeprowadzono na terenie bazy paliwowej położonej w północno-wschodniej Polsce, gdzie poziomy gliny lodowcowej zostały zanieczyszczone olejem napędowym w obrębie pola podziemnych zbiorników. W artykule przedstawiono charakterystykę mikrostruktury gruntu niezanieczyszczonego (NS) oraz gruntu zanieczyszczonego (SR) in situ olejem napędowym (ON). Dokonano również analizy zmian parametrów geologiczno-inżynierskich: uziarnienia, gęstości właściwej szkieletu gruntowego, granic konsystencji oraz wskaźnika plastyczności w zależności od stopnia zanieczyszczenia ON past gruntowych sporządzonych z gruntu NS. Badania mikrostrukturalne przeprowadzono na próbkach NNS, natomiast do badań parametrów geologiczno-inżynierskich przygotowano serię past zawierających 0, 2, 4, 8, 12, 16% wag. ON w stosunku do suchej masy gruntu. Pomiary uziarnienia przeprowadzone metodą pipetową i mikroagregatową wykazały, że wraz ze wzrostem zanieczyszczenia zwiększa się zawartość frakcji piaskowej, a spada zawartość frakcji pyłowej i iłowej. Większy zakres zmian uziarnienia uzyskano z badań metodą mikroagregatową. Wartości granicy skurczalności, plastyczności i płynności oraz wskaźnika plastyczności wzrosły, a gęstości właściwej szkieletu gruntowego zmalały wraz ze wzrostem zawartości ON. Spadek wartości gęstości właściwej szkieletu gruntowego jest związany z adsorpcją węglowodorów na ziarnach i cząstkach mineralnych. Badania mikrostrukturalne wykonane z zastosowaniem skaningowego mikroskopu elektronowego (SEM) oraz programu komputerowego STIMAN wykazały zwiększenie porowatości, liczby mezoporów, średnich i maksymalnych wartości obwodu, powierzchni i średnicy porów w gruncie SR. Mikrostruktura gruntu SR stała się bardziej izotropowa, na co wskazują spadek wartości wskaźnika anizotropii mikrostruktury i liczby porów szczelinowatych oraz wzrost średniej wartości współczynnika formy porów.

EN

In this paper the microstructural characteristic of glacial till polluted in situ with diesel oil (ON) is presented as well as the analysis of: particle size distribution, Atterberg limits, plasticity index and particle density in relation to the degree of the soil pollution. The microstructural study was conducted on undisturbed soil samples, while the engineering-geological parameters were tested on soil pastes containing 0, 2, 4, 8, 12, 16% of ON. The obtained results showed that as the pollution degree increases the content of silt and clay decreases and the content of sand increases. It was observed in polluted samples that the values of Atterberg limits and plasticity index increased, while the particle density values decreased due to adsorption of hydrocarbons on soil particles. Microsturctural analysis was conducted using Scanning Electron Microscope (SEM) and STIMAN software. The analysis revealed an increase of values in such morphological parameters as: total porosity, number of mesopores, pore diameter, pore area and pore perimeter. The microstructure converted to more isotropic, which was supported by decrease in coefficient of anisotropy and number of fissure pores.

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Optyczno-elektroniczny sposób określania składu granulometrycznego gruntów i możliwości zastosowania w geologii inżynierskiej

Kamiński S., Trzciński J.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2008

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T. 34, z. 4

623-632

PL

Obecnie istnieją już techniczne możliwości uniknięcia trudnych manualnie i pracochłonnych pomiarów składu granulometrycznego gruntów (np. analiza sitowa czy areometryczna). Parametr ten można badać za pomocą urządzeń optyczno-elektronicznych typu Elsieve, które coraz powszechniej używane są w Polsce. Takie urządzenia pomiarowe wykorzystuje się do wyznaczenia krzywej granulometrycznej ziaren o wymiarach od 0.5 mim do 100 mm. Dodatkowo istnieje możliwość określenia kształtu ziaren według pomiarów 3D oraz innych parametrów uziarnienia. System pomiarowy może składać się z dowolnej liczby urządzeń połączonych indywidualnie z komputerem rejestrującym. Każdy indywidualny komputer przyrządu pomiarowego połączony jest z komputerem centralnym pełniącym rolę serwera. Stworzona sieć komputerów pozwala jednocześnie rejestrować wyniki pomiarowe na komputerze obsługującym dane urządzenie pomiarowe, jak również na pozostałych komputerach. Taki system pomiarowy jest używany do badań uziarnienia gruntów i innych geomateriałów w laboratorium Instytutu Hydrogeologii i Geologii Inżynierskiej Wydziału Geologii UW.

EN

Nowadays there are available technical possibilities to avoid manually difficult and work-consuming measurements of soil grain composition (e.g. sieve or sedimentation analysis). Such measurements can be replaced by optical-electronic instruments called Elsieve that are more common in Poland. The instruments are used for determination of grain-size distribution of gains and particles with diameter form 0.5 mim to 100 mm. Additionally there is possibility to determine shape of grains by 3D measurements and other graining parameters. The measuring system can consist of any number of instruments, connected with recording computer. Every computer of any measuring instruments is connected with the server. The created network allows to save measuring results at computer that works with particular instrument and at other computers. Such a system is used for measurements of soil and other geomaterials grain composition in laboratory at Institute of Hydrogeology and Engineering Geology, Faculty of Geology, University of Warsaw.

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Mechanizm rozpadu piaskowców wywołany krystalizacją soli

Słaby E., Galbarczyk-Gąsiorowska L., Trzciński J., Górka H., Łukaszewski P., Dobrowolska A.

Przegląd Geologiczny

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2001

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Vol. 49, nr 2

124-133

PL

Geneza krzemieni i czertów należy do największych zagadek współczesnej geologii. Od 1999 r. zespół polsko-amerykański, reprezentowany przez autorów niniejszego artykułu, prowadzi badania nad wyjaśnieniem warunków tworzenia się krzemieni górnojurajskich w rejonie Ożarowa (NE obrzeżenie Gór Świętokrzyskich). Stwierdzono istnienie antykorelacji pomiędzy *D i *18O. Obecne badania koncentrują się nad dwoma najbardziej prawdopodobnymi modelami genetycznymi krzemieni: (1) zmian temperatur na skutek działalności podmorskich źródeł hydrotermalnych, (2) samoorganizującej się katalitycznej krystalizacji. Uzyskane wyniki będą stanowić istotny wkład do badań nad genezą krzemieni i czertów z różnowiekowych formacji skalnych.