Wyniki wyszukiwania - BazTech

1

The influence of thermophysical properties of frozen soil on the temperature of the cast-in-place concrete pile in a negative temperature environment

Liu Ziying, Yu Tianlai, Yan Ning, Gu Lipeng

Archives of Thermodynamics

|

2023

|

Vol. 44, no 2

21--48

EN

Thermophysical properties of frozen soil have a great influence on the quality of cast-in-place concrete piles. In this paper, the embedded concrete temperature monitoring system is used to test the variation law of the concrete temperature during the construction of the bored pile. Thermophysical properties of permafrost around piles are tested. Based on the theory of three-phase unsteady heat conduction of soil, the influence of specific heat capacity, thermal conductivity, thermal diffusivity, and latent heat of phase transformation on the temperature change of a concrete pile is systematically studied. The thermal parameter is obtained which exerts the most significant influence on the temperature field. According to the influence degree of frozen soil on pile temperature, the order from high to low is thermal conductivity, thermal diffusivity, latent heat of phase change, and specific heat capacity. The changes in pile wall temperature caused by the change of these properties range between 2.60–10.97◦C, 1.49– 9.39◦C, 2.16–2.36◦C, and 0.24–3.45◦C, respectively. The change percentages of parameters vary between 35.77–47.12%, 12.22–40.20%, 12.46–32.25%, and 3.83–20.31%, respectively. Therefore, when designing and constructing concrete foundation piles, the influence of the thermal conductivity of frozen soil on concrete pile temperature should be considered first. The differences between the simulated and measured temperature along the concrete pile in the frozen soil varying with the respective thermal properties are: –2.99– 7.98◦C, –1.89–4.99◦C, –1.20–1.99◦C, and –1.76–1.27◦C. Polyurethane foam and other materials with small thermal conductivity can be added around the pile to achieve pile insulation.

2

Air temperature in high-altitude areas as exemplified by the Tatra Mountains

Jurczak Krzysztof, Kędzia Stanisław

Meteorology Hydrology and Water Management. Research and Operational Applications

|

2021

|

Vol. 9, Iss. 1-2

1--13

EN

The climate of a high-altitude postglacial cirque, such as Kozia Dolinka, is conducive to the occurrence of permafrost. Both the depth of permafrost and the area it covers, as well as the presence of year-round snow patches, can serve as indicators for assessing the impact of global warming on the climate of mountains, including the Tatras. With few meteorological stations to survey the remote and inaccessible high-altitude areas of the Tatra Mountains, any research must rely on measurements spanning limited time periods. Against this background, the 5-year series of temperature measurements from the Kozia Dolinka cirque obtained by the Institute of Geography and Spatial Organization of the Polish Academy of Sciences (IGiPZ PAN) can be used to analyze air temperature patterns on concave and convex terrain forms in the alpine climate zone if compared to the results of measurements from stations of the State Hydrological and Meteorological Service located nearby, i.e. the Kasprowy Wierch HighMountain Meteorological Observatory and the Hala Gąsienicowa Nival Research Station of the Institute of Meteorology and Water Management, National Research Institute (IMGW-PIB). This study confirms that there is a relationship between air temperature and the formation and duration of snow cover on concave and convex terrain forms. It also reveals a hitherto unknown fact that concave terrain forms, i.e. postglacial cirques, of the alpine zone have milder thermal conditions in winter than convex terrain forms. The analyses highlight the need for further, more detailed research using modern automated meteorological stations.

3

Jeziora Parku Narodowego Pojezierze Smoleńskie (Rosja)

Skrzypczak Robert

Przegląd Geologiczny

|

2020

|

Vol. 68, nr 1

50--53

EN

The Smolensk Lakeland National Park is situated north of Smoleńsk in the NW Russia. Its morphology is associated with the last European ice sheet: glacial erosion and accumulation, glacial water activity, locally with the so-called thermokarst process or karst in the strict sense. The post-glacial morphological depressions are filled with lake waters. The most interesting lakes are: Chistik, Mutnoye, Balshoye and Maloye Striechnoye, Glubokoye, Dolgoye, Krugloye, Pietrovskoye, Bukino, Gorodishche, Svyatec, Sapsho, Polovia, Gniloye, Rytoye, Dgo, Shchuch’ye, Baklanovskoye, Bachovskoye, Vervizhskoye, Pal’tsevskoye and Bieloye. The Smolensk Lakeland National Park is one of a few territories in Europe where the beauty of nature and landscapes dominate the long-standing human presence. Nowadays, there are a few residents, a growing number of patients, seasonal campers and tourists in the park area.

4

Studying permafrost by integrating satellite and in situ data in the northern high‑latitude regions

Gido Nureldin A. A., Bagherbandi Mohammad, Sjöberg Lars E., Tenzer Robert

Acta Geophysica

|

2019

|

Vol. 67, no. 2

721--734

EN

There is an exceptional opportunity of achieving simultaneous and complementary data from a multitude of geoscience and environmental near-earth orbiting artificial satellites to study phenomena related to the climate change. These satellite missions provide the information about the various phenomena, such as sea level change, ice melting, soil moisture variation, temperature changes and earth surface deformations. In this study, we focus on permafrost thawing and its associated gravity change (in terms of the groundwater storage), and organic material changes using the gravity recovery and climate experiment (GRACE) data and other satellite- and ground-based observations. The estimation of permafrost changes requires combining information from various sources, particularly using the gravity field change, surface temperature change, and glacial isostatic adjustment. The most significant factor for a careful monitoring of the permafrost thawing is the fact that this process could be responsible for releasing an additional enormous amount of greenhouse gases emitted to the atmosphere, most importantly to mention carbon dioxide (CO2) and methane that are currently stored in the frozen ground. The results of a preliminary numerical analysis reveal a possible existence of a high correlation between the secular trends of greenhouse gases (CO2), temperature and equivalent water thickness (in permafrost active layer) in the selected regions. Furthermore, according to our estimates based on processing the GRACE data, the groundwater storage attributed due to permafrost thawing increased at the annual rates of 3.4, 3.8, 4.4 and 4.0 cm, respectively, in Siberia, North Alaska and Canada (Yukon and Hudson Bay). Despite a rather preliminary character of our results, these findings indicate that the methodology developed and applied in this study should be further improved by incorporating the in situ permafrost measurements.

5

Reflection of climatic changes during interpleniglacial in the geoecosystems of South-Eastern Poland

Starkel L., Michczyńska D. J., Gębica P.

Geochronometria

|

2017

|

Vol. 44, no. 1

202--215

EN

About 70% of the last cold stage was taken by transitional phases of continuous fluctuations of climate and permafrost extension. All this is reflected especially well in slope types and the thickness of slope, fluvial and aeolian deposits. Very distinct and relatively fast changes took place around 33–30 ka BP: the aridification of climate with an ice sheet transgression, expansion of continuous permafrost and the onset of loess deposition. The greatest transformations of slopes and river valleys in the Carpathians and Subcarpathian Basins took place not in the coolest phases but during the Interpleniglacial. The authors exemplified a number of sites in Southern Poland documenting frequent fluctuations of climate and permafrost from that 25–30 ka long period. Calibrated dates of dated episodes correlate well with the δ18O curve from Greenland with frequent warmings. These rapid warmings are reflected in the higher rate of aggradation in valley floors and thick colluvial material deposited over slopes, both combined with a retreat of permafrost. The comparison with the Greenland 18O curve is valuable to establish a comparable chronology of events, even for such a distant area like Central-Eastern Europe.

6

Are there any active rock glaciers in the Tatra Mountains?

Kędzia S.

Studia Geomorphologica Carpatho-Balcanica

|

2014

|

Vol. 48

5--16

EN

Research on rock glaciers have been conducted in the Tatra Mountains for about 100 years. About 30 years ago, there were papers suggesting that part of the Tatra rock glaciers was formed during the Little Ice Age. About 20 years ago, permafrost was discovered in the mountains. This discovery marked the beginning of research on the activity of rock glaciers. Ten years ago, a study was carried out on the rock glacier near the Velké Hincovo Pleso lake, which excluded any activity of this glacier in the last few hundred years, despite the high probability of the existence of permafrost in it. The following paper presents the results of lichenometric dating conducted for the activity of rock glaciers in the Świstówka Roztocka and the Buczynowa valleys.

7

Gazohydraty - nowy rodzaj paliw kopalnych

Zagorski J.

Przegląd Geologiczny

|

2013

|

Vol. 61, nr 8

452--459

EN

Unconventional hydrocarbon resources in last years draw the attention of petroleum geologists. Significant position take the gas hydrates, first of all due to occurrences in many regions of the world and the size of the potential resources. These accumulations are localized in Arctic regions with permafrost as well as offshore. First gas hydrate discovery occurred in Siberian gas field Messoyakha in permafrost zone and similar accumulations were found in Alaska. Offshore occurrences are located mainly on continental slope. Drillings and samples from permafrost and seabed provided vast amount of data concerned conditions of gas hydrates formation and concentration and allow to better constrain the volume of hydrate-bearing sediments and their gas yield. Resources of hydrocarbons contained in gas hydrate deposits represent a vast energy source potential. Still essential problem is to elaborate efficient commercial production technology. So far positive developments regard only laboratory or semi-commercial scale.

8

Zmienność maksymalnej miąższości czynnej warstwy zmarzliny w rejonie Bellsundu (W Spitsbergen) w okresie 1986-2009

Marsz A. A, Pękala K., Repelewska-Pękalowa J., Styszyńska A.

Problemy Klimatologii Polarnej

|

2011

|

nr 21

133-154

PL

W pracy przebadano wpływ temperatury powietrza, cyrkulacji atmosferycznej i temperatury powierzchni morza na Prądzie Zachodniospitsbergeńskim na zmiany maksymalnej miąższości czynnej warstwy zmarzliny na Calypsostrandzie (Bellsund) w latach 1986-2009. Stwierdzono, że podstawowym czynnikiem klimatycznym, regulującym tą zmienność jest temperatura powietrza w Svalbard-Lufthavn, co pozwala na rekonstrukcję przebiegu zmian miąższości czynnej warstwy zmarzliny na Calypsostrandzie w okresie 1911-2009. W badanym okresie nie zachodzą istotne związki między miąższości czynnej warstwy zmarzliny a zmiennością wskaźników cyrkulacji hemisferycznej (AO) i regionalnej (NAO). Bardzo silny wpływ na miąższość czynnej warstwy zmarzliny na Calypsostrandzie wywierają zmiany temperatury powierzchni Morza Grenlandzkiego w rejonie przepływu ciepłego Prądu Zachodniosptsbergeńskiego.

EN

The measurements of thickness of the sling part of permafrost thawing in summer i.e. permafrost active layer were made on Spitsbergen in the Bellsund region in 1986-2009 within the polar expedition programs accomplished by Maria Curie Skłodowska University, Lublin. The investigations included the seaside plain Calypsostranda situated on the western side of Recherche Fiord in the forefield of the glaciers Scott and Renard (Fig. 1) constituting a complex of raised marine terraces formed during the glacioisostatic movements. Maximal thickness of active permafrost (CWCmax) was determined using the sounding method in 10 chosen points localized within the geocomplexes typical of tundra (Fig. 2). The average many years' maximal values of active layer thickness are presented in Table 1. The paper presents the results of studies on the effect of air temperature, atmospheric circulation and sea surface temperature on Western Spitsbergen Current on the variation of maximal thickness of active permafrost layer. As follows from the studies the interyear changes of maximal thickness of the active layer on Calypsostranda are relatively susceptible to the changes of air temperature which indicates prompt susceptibility to changes. The tendency towards the increase of ground thawing depth on Calypsostranda in 23 years under consideration is not stable and can change significantly depending on temperature. Though there is no doubt that during the last 4-5 years there have appeared signs of quickened increase of active layer thickness on Calypsostranda (Fig. 4), the conclusion about permanent degradation of permafrost seems to be risky at present. Of the climatic factors the essential one affecting the interannual changeability of maximal thickness of the active layer on Calypsostranda is air temperature in Svalbard-Lufthaven. The regression analysis showed (Equation 1) that the variance CWmax is explained best by the merged May and June temperatures (SVsumT_V-VI) and the average March temperature (SVT_III) (Fig. 5). Changeability of these both variables accounts for 83% variance CWCmax. Equation [1] allows to reconstruct the course of changes of maximal thickness of the active layer on Calypsostranda in 1911-2009 (Fig. 6). In the studied period distinct and essential connections between CWCmax on Calypsostranda and changeability of hemispheric circulation indices (AO) or regional (NAO) were not found. However, temperature changes of Greenlandic Sea surface in the region of warm Western Spitsbergen Current flow (Table 3) affect significantly on air temperature on Spitsbergen and as a result on active layer thickness on Calypsostranda. As the hitherto course of maritime processes indicates a gradual decrease in heat resources carried by Western Spitsbergen Current, one can deduce that air temperature in the region of Spitsbergen will drop in near future. That will probably lead to a decrease in thawing depth on Calypsostranda. Differentiation in active layer thickness is dependent on local factors such as configuration, aspect of slopes, vegetation cover as well as kind and extent of water mobility in covers as it was reported earlier.

9

Wyniki badań hydrogeologicznych w strefie występowania głębokiej wieloletniej zmarzliny w otworze wiertniczym Udryń PIG 1

Honczaruk M., Śliwiński Ł.

Biuletyn Państwowego Instytutu Geologicznego

|

2011

|

nr 445 Hydrogeologia z. 12/1

203--216

PL

W niniejszym artykule zaprezentowano wyniki badań hydrogeologicznych w otworze badawczym Udryń PIG 1. Otwór odwiercono w celu zweryfikowania hipotezy występowania plejstoceńskiej wieloletniej zmarzliny na obszarze suwalskiego masywu anortozytowego (SMA). Zafiltrowano w nim warstwę wodonośną piasków drobnoziarnistych kredy dolnej. W różnych odstępach czasu wykonano profilowania temperaturowe, prowadzone w trakcie stabilizacji termicznej otworu zarówno przed, jak i po pompowaniu pomiarowym. Zarejestrowano minimalną temperaturę wody w otworze, wynoszącą –0,395°C na głębokości 383,0 m. Wysokie wartości współczynnika oporów przepływu sugerują zlodzenie części warstwy wodonośnej piasków drobnoziarnistych albu, której jedynie część bierze udział w dopływie wody do filtra. Szybko przebiegająca stabilizacja depresji wskazuje na możliwość występowania procesu przemiany fazowej lodu w wodę na skutek spadku ciśnienia i wymuszenia przepływu w warstwie wodonośnej. Hipotezę o występowaniu wieloletniej zmarzliny jednoznacznie potwierdzają wyniki analiz chemicznych pobranych próbek wody. Mineralizacja ogólna, skład oraz typ hydrochemiczny i zawartość izotopu 18O wskazują na metamorfizm kriogeniczny.

EN

This paper presents the results of hydrogeological research carried out in the Udryń PIG 1 borehole. It was drilled in order to verify the hypothesis of the occurrence of Pleistocene permafrost in the Suwalki anorthosite massif. The borehole was filtered in Lower Cretaceous fine-grained sand aquifer. Temperature profiling was performed at various intervals, during the thermal stabilization of the borehole, both before and after the pumping test. Minimum water temperature of –0.395°C was recorded in the well at a depth of 383.0 m below the surface. High values of the flow resistance coefficient suggest that the Albian fine – grained sand aquifer is iced, which implies that only part of the water is supplied to the screen. Fast stabilization of drawdown suggests the possibility of a phase transformation process of ice into water by lowering the pressure and forcing the water flow in the aquifer. The hypothesis of the existence of permafrost is unequivocally confirmed by the results of chemical analysis of water samples. The general mineralization, composition and hydrochemical type of the water and 18O isotope content suggest cryogenic metamorphism.

10

Zmiany termiki gruntu w Hornsundzie (SW Spitsbergen) w latach 1990-2009

Dolnicki P.

Problemy Klimatologii Polarnej

|

2010

|

nr 20

121-127

PL

W pracy przedstawiono wyniki pomiarów temperatury gruntu mierzonych w ogródku meteoro-logicznym Polskiej Stacji Polarnej w Hornsundzie dla dwudziestolecia (1990-2009). Zmienność temperatury gruntu analizowanego okresu zestawiono oddzielnie dla zdefiniowanego w tytule wielolecia oraz dla okresu 2006-2009, który rozszerza wcześniejsze opracowania o kolejne lata. Maksymalną temperaturę gruntu na głębokości 100 cm odnotowano w sierpniu 2009 roku (3,6°C). Najniższą temperaturę okresu letniego na tej samej głębokości odnotowano w sierpniu 1994 roku (1,1°C). Tak wyraźna różnica pomiędzy skrajnymi wartościami nie znajduje swojego odbicia w wieloletnich trendach. Przebieg średnich wartości temperatury rocznej i linii trendu w okresie 2006-2009 jest silnie związany z wysoką temperaturą zarejestrowaną w 2006 roku. Wysokie wartości średnich miesięcy letnich są niwelowane przez niskie wartości temperatury okresu zimowego. Tendencje wzrostowe temperatury gruntu rysujące się w okresie 1990-2009 i malejące w ostatnich latach nie wykazują istotności statystycznej.

EN

In the paper there are presented results of the measurement of ground temperature measured in the meteorological station of Polish Polar Station in Hornsund for the period of twenty years (1990-2009). The variability of temperatures of the analyzed period was compared separately for the defined in the title more than one year period and the period of 2006-2009, which extends the former works for another years. The maximal temperature of the ground on the depth 100 cm were measured in August, 2009 (3.6°C). The lowest temperature of the summer period at the same depth were measured in August 1994 (1.1°C). Such a significant difference between extreme values does not have a reflection in the many year trends. The course of the mean annual temperatures and trend line in the period of 2006-2009 is strongly connected with the high temperatures measured in 2006. The high values of mean tempera-tures of summer months are leveled by the low temperatures of the winter period. The growing tendencies of the ground temperatures in 20 years period and diminishing tendencies in the last years are not statistically significant. High temperatures of the ground, which occurred during last years characterized particularly summer seasons. This fact had influence on the more activity of the surface layer of permafrost. Therefore there is no reason to make final conclusions about significant fluctuation of the roof of the permafrost in Hornsund.

11

Warstwa czynna i występowanie wieloletniej zmarzliny w pobliżu Polskiej Stacji Polarnej w Hornsundzie na Spitsbergenie w świetle badań geofizycznych

Dobiński W., Leszkiewicz J.

Problemy Klimatologii Polarnej

|

2010

|

nr 20

129-142

PL

Z dotychczasowych badań wynika, iż występowanie wieloletniej zmarzliny na Svalbardzie jest powszechne i ma ona charakter ciągły. Generalnie przyjmuje się, że grubość warstwy zmarzliny w większych niezlodowaconych dolinach sięgać może 100 m natomiast w wysokich górach znajdujących się w głębi wyspy miąższość ta sięgać może nawet 400-500 m (Humlum i in. 2003). Zmarzlina na Spitsbergenie, podobnie jak w wielu innych obszarach zimnych, ogrzewa się i podlega degradacji (Isaksen i Sollid 2002). W okresie ostatniego dwudziestolecia kilkukrotnie przeprowadzono badania warstwy czynnej i zmarzliny w bezpośrednim sąsiedztwie Polskiej Stacji Polarnej w Hornsundzie. Pomierzono temperaturę gruntu do głębokości 2 m na dwóch stano-wiskach w pełnym sezonie rocznym. Zmarzlinomierze Danilina posłużyły do określenia głębokości warstwy czynnej na 13 stanowiskach w obrębie wyniesionych teras morskich. W lecie 2009 roku m. in. na podniesionej terasie morskiej przeprowadzono badania geofizyczne mające na celu pozyskanie informacji dotyczących wystę-powania wieloletniej zmarzliny w tej okolicy. W badaniach zastosowano metody geofizyczne: elektrooporową i sejsmiczną. Wyniki badań geofizycznych na terasie nadmorskiej nie potwierdzają występowania permafrostu. Być może ze względu na możliwy wpływ wody morskiej i aerozoli zawierających sól ma on tutaj postać tzw. kriotyczną, to jest pomimo ujemnej temperatury pozostaje niezamarznięty. Wyniki badań geofizycznych nie wykluczają obecności stale przemarzniętego gruntu poniżej głębokości, do których interpretowano wyniki badań geofizycznych. Oznacza to jednak, że występowanie zmarzliny w rejonie fiordu Hornsund jest o wiele bardziej zróżnicowane niż dotychczas sądzono. Może mieć też ona charakter nieciągły w tym rejonie, gdzie średnia roczna temperatura powietrza wzrosła w ostatnich latach do ok. -3°C.

EN

Permafrost research on the Svalbard Archipelago shows, that permafrost occurence has the continuous character on this area. Published data shows that in general permafrost extends to the depth of 100 meters in the large nonglaciated valleys, and in the interior mountains it can reach even 400-500 meters depth. Permafrost on the Spitsbergen is degrading similarly as in the other arctic areas. In the last 20 years several times research on the active-layer depth were conducted in the vicinity of the Polish Polar Station in Hornsund, Spitsbergen. Traditional ground thermometers as well as Pt-100 sensors were used for measurements. Ground temperature were measured to the 2 m depth on the two locations all-year round. Danilin’s permafrost meters were used for the determination of the active-layer depth at the 13 locations on the marine terraces. In 2009 on the near-shore marine terrace geophysical surveys were made. The aim of the surveys was to collect data concerning permafrost occurrence in this area. In the research electroresistivity soundings (VES) and refraction seismics methods were used. Results of the geophysical surveys not confirmed the existence of frozen material in the ground. Probably the influence of salt water from the fjord, or salt transported by the air aerosols caused that the temperature of freezing decreased below the 0°C and existence of the permafrost in this place has the cryotic form. It means that existence of permafrost in the Hornsund area has much more diverse character than believe so far. In the Hornsund area where mean annual air temperature reach ca. -4°C permafrost probably has probably the discontinuous character.

12

Geophysical methods in research of permafrost in the Tatra Mountains and northern Scandinavia

Dobiński W.

Landform Analysis

|

2009

|

Vol. 10

26-32

EN

A set of geophysical methods were implemented in the research conducted on permafrost of the Tatra Mountains and the Abisko area, Northern Sweden. Results of geophysical surveys show evidence of permafrost in both areas. Comparative studies on the occurrence of permafrost in the Tatras and in the Abisko area indicate that contemporary active as well as fossil permafrost might occur in both locations. Results of the electric resistivity, electromagnetic, shallow refraction seismic, and ground penetrating radar methods reveal similar results and might be successfully used in indirect research on permafrost in the mountainous regions.

13

Permafrost and periglacial environment of Western Tibet

Fort F., van Vliet-Lanoe B.

Landform Analysis

|

2007

|

Vol. 5

25--29

14

Geofizyczne badania współczesnej i plejstoceńskiej zmarzliny na Kasprowym Wierchu

Dobiński W., Żogała B., Wziętek K., Litwin L.

Przegląd Geofizyczny

|

2006

|

Z. 1

71-82

PL

Analizy klimatyczne pokazują, że Szczyt Kasprowego Wierchu jest prawdopodobnie miejscem występowania granicy nieciąglej zmarzliny. W celu sprawdzenia tej hipotezy wykonano badania terenowe z wykorzystaniem następujących metod geofizycznych: punktowych sondowań elektrooporowych, płytkich sondowań elektromagnetycznych, pomiarów temperatury BTS oraz obrazowania elektrooporowego. Rezultaty badań potwierdzają tezę o występowaniu wieloletniej zmarzliny na Kasprowym Wierchu na wysokości od około 1850 m npm. Pozwalają podtrzymać także tezę o występowaniu na głębokości ok. 1-4 m współczesnego, związanego z obecnym klimatem permafrostu, oraz znacznie starszego, być może plejstoceńskiego permafrostu na głębokości ok. 20 metrów pod powierzchnią gruntu.

EN

Climatological analysis shows that Kasprowy Wierch summit is the place where lower limit of discountinuous permafrost probably occurs. DC resistivity tomography, BTS, VES, and shallow electromagnetic soundings were used in the fieldwork to examine the possibility of permafrost occurrence there. The data gathered indicates that permafrost is present from the peak of Kasprowy Wierch to the altitude of about 1850 m asl. The results support the thesis on the existence of two layers of permafrost in the Tatra Mountains: the active one, connected with the present climate, which occurs on Kasprowy Wierch at the depth of about 1.2-4.0 m and the one of pleistocene origin. The depth at which the latter occurs depends on altitude above sea level, and occur from about twenty meters below the ground surface.