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EN
In this paper, 13 selected sites situated in the Bielany and Tyniec Landscape Park and its surroundings within the Kraków Gate area are the subjects of comparative description, being examples of essential and significant geotouristic potential. Almost all of them show karstified Oxfordian Upper Jurassic limestones at the centre of Kraków at the foot of the Wawel Hill and in the districts of Tyniec, Zakrzówek, Podgórze, Wola Justowska, in the villages of Piekary and Jeziorzany. Among these sites is Smocza Jama Cave. Pleistocene loess in the Salwator district of Kraków is also described. All sites are various and picturesque. They are also important examples displaying products of very complex geological processes. The comparative evaluation of geotouristic potential of all the thirteen sites was made to meet tourists', educators' and investors' expectations and needs to increase their geotouristic significance. In general, interest in them as geotouristic abiotic nature objects has been growing regularly up to now. They have become very widely known in Poland and could become very popular worldwide, too.
PL
W artykule przedstawiono wyniki analizy składu granulometrycznego i mineralogicznego zapraw glinianych stosowanych w tradycyjnym budownictwie wiejskim. Jest to kolejny etap badań mających na celu odtworzenie dawnych technik murarskich stosowanych w międzyrzeczu Warty i Neru, w centralnej części Polski. Polegały one na wznoszeniu budynków z miejscowego kamienia wapiennego (opoki) i cegły, uzyskiwanej metodą polowego wypału, wiązanych zaprawą glinianą. Obiekty zrealizowane w tej technologii stanowią o wyraźnej odrębności architektonicznej oraz krajobrazowej tego regionu i są coraz częściej uznawane za istotne dziedzictwo kultury materialnej.
EN
The article presents the results of the analysis of the granulometric and mineralogical composition of clay mortars used in traditional rural construction. This is the next stage of research aimed at reproducing old masonry techniques used in the area between the Warta and Ner rivers, in the central part of Poland. They involved the buildings from local soft limestone and brick obtained by field firing, bonded with clay mortar. Objects constructed using this technology constitute a clear architectural and landscape distinctiveness of this region and are increasingly recognized as an important heritage of material culture.
PL
W artykule przedstawiono podstawowe informacje na temat wpływu dodatku mączki wapiennej do betonu na właściwości mieszanki betonowej i stwardniałego betonu.
EN
In light of restrictions on the use of cement clinker, related to the negative environmental impact of its production, the increased use of ground limestone in concretes, both as an admixture to concrete and as a main component of cement, is imminent. The article presents basic information on the effect of adding limestone powder to concrete on the properties of the concrete mixture and hardened concrete. In properly designed concrete, limestone powder in the amount of up to 10% of the weight of cement can be used without significant negative effects on its consistency, strength and durability. With larger amounts of limestone, the effect depends on the type and fineness of limestone, while a reduction in the strength and durability of concrete proportional to the limestone content can be expected.
EN
According to Council Directive 98/83/EC on the quality of water intended for human consumption, concentration of the manganese in the drinking water should not exceed 0.05 mg/l. However, this level of manganese concentration is higher ingroundwaterof a community (Vitia town) in Kosovo. Groundwater is used for drinking supply of some villages and is only chlorified continuing to the reservoir from where is gravitationallydisseminated to the villages. The manganese level of the water is at the range 0.3 to 0.6 mg/l. Limestone has been provenby many researchers to be a very effective filter material in manganese removal for groundwater.A miniature filtration unit was modeled to investigate the removal efficiency of manganese.The unit consists of local limestone, where a single materialis folded in three layers of different grainsizes. In fact, the aim of this paper was to assess whether limestone as a single material acting as a "multi-media filter" can reduce the manganese concentration in groundwater. On the basis of the analysis of the single snapshot sample,the removal of manganese achieved more than 95% in filtered water. Particularly, this study demonstrates that filtering the water through three layers of different grain sizes of limestone ("multi-media limestone filter") can be a good alternative for manganese removal in groundwater.
PL
W artykule przedstawiono badania efektów zastosowania w betonie 8 różnych mączek wapiennych, poprzez zastąpienie nimi aktywnego dodatku pucolanowego. Wyniki badań potwierdziły ich przydatność, a ostateczna ocena może nastąpić na podstawie badań wstępnych. Użycie mączek wapiennych bezpośrednio do betonu wpisuje się w działania zmierzające do obniżenia emisyjności tego bardzo ważnego materiału konstrukcyjnego.
EN
The article presents research on the effects of using 8 different limestone powders in concrete by replacing the active pozzolanic additive with them. The results of the research confirmed their suitability, and the final assessment may be based on initial test. The use of lime powder directly into concrete is part of the activities aimed at reducing the emissivity of this very important construction material.
EN
Khao Khwang Formation is widely distributed in central Thailand. It is represented by Late Pennsylvanian to Middle Permian thick-bedded limestone with chert nodules. Rock samples belonging to this formation have been collected. They are light to dark grey, thick-bedded to massive limestone with black nodular cherts. The abundant and extraordinarily gigantic bivalve Alatoconchidae together with fusulinoidean fauna (Verbeekina verbeeki, Colania douvillei and Pseudodoliolina pseudolepida), fragments of coral, ammonoid, brachiopod, sponge, gastropod, etc. were observed. Based on the characteristic fusulinoidean fauna, it indicates Capitanian in age. Microscopically, limestone samples were classified as bioclastic rudstone and packstone. The detailed lithologic and carbonate microfacies observations, Alatoconchidae beds, deposited parallel to the bedding plane and related with oncoids and microbial, are autochthonous in shallow marine. Condensed accumulation of other fossil fragments found in the study areas might be transported by gravity flow.
EN
At a nature-preserve protected site in the Julian Alps (NW Slovenia), in the Pod Peski valley, red fillings of megalodontid bivalves occur within the Upper Triassic Dachstein limestone. Based on optical and cathodoluminescent microscopy and X-ray fluorescence (XRF) analysis, four generations of shell fillings were recognized, some of which contain both cement and sediment subgenerations. Logging and sampling of the limestone sequence a few meters below and above the “main” layer containing the megalodontids mentioned above revealed that the limestone is characterized by solution voids similar to the megalodontids. Namely, these voids are also filled with reddish multigeneration sediment with alternating calcite cement. Adjacent neptunian dykes were studied to clarify their influence on the last generation fillings. Two of them, located directly on the “main” layer with red-filled megalodontids, contain planktonic foraminifera, indicating Middle Jurassic or younger age. The next two neptunian dykes are located directly above the “main” layer, and one contains clasts with calpionellids characteristic of the Late Jurassic/Early Cretaceous. The last dyke explored is located a few tens of meters from the “main” layer and is several hundred meters long. In a few sample from this dyke Early Cretaceous planktonic foraminifera were identified. Microscopic analysis revealed that the reddish sedimentary fillings are part of a complex palaeokarst system that produced the first three generations of fillings, and in the last (fourth) generation we noted similarities between the megalodontid fillings and neptunian dykes on the “main” bedding plane. In addition, a Santonian–Maastrichtian sedimentary fill with globotruncanid foraminifers were discovered in the upper part of the succession in one of the solution voids.
EN
This study aimed to reveal the petrography and physical-mechanical properties of limestones, which have an important reserve and are used as marble, in Tut district of Adıyaman province, which is one of the important cities of southeast Anatolia. As a result of petrographic analysis of the rock known commercially as Emprador, it was determined that it is bioclastic limestone with abundant nummulite fossils. Density, dry and saturated unit weight, water absorption, surface roughness, abrasion resistance and uniaxial compressive strength tests were applied to determine the physical and mechanical properties of the limestones. According to the test results obtained, the density of the limestones, dry unit weight, saturated unit weight, water absorption by weight, water absorption by volume, average surface roughness, ten points roughness average, maximum roughness value, Bohme abrasion resistance and uniaxial compressive strength values were determined as 2.486 gr/cm3, 2.478 gr/cm3, 2.52 gr/cm3, 1.482%, 3.644%, 3.31 μm, 16.24 μm, 20.03 μm, 8.958 cm3/50cm2 and 1004.03 kgf/cm2 respectively. The results show that the limestones in and around Tut (Adıyaman) county can be used in large areas for decorative purposes, with their physical and mechanical properties, as well as their colour tone and the texture formed as a result of the calcite veins being shaped like a natural pattern.
PL
W artykule przedstawiono wyniki badań, jakie uzyskano w przypadku betonu mostowego wykonanego na cemencie portlandzkim wapiennym CEM II/A-LL. Zastosowanie tego cementu pozwala na znaczną redukcję śladu węglowego wbudowanego w konstrukcjach mostowych, średnio o 12% w porównaniu z rozwiązaniami na bazie cementów CEM I. Kamień wapienny, jako główny składnik nieklinkierowy cementu, wprowadza do kompozytów cementowych wiele dodatkowych właściwości, które również zostały przedstawione w artykule. W przyszłości, w przypadku ograniczonej dostępności dobrej jakości innych, popularnych składników cementu (S, V) oraz wapienia i opartych na nim cementów może stać się naturalnym wyborem do redukcji śladu węglowego w betonie.
EN
In this article presented test results which obtain for bridge concrete made on Portland limestone cement CEM II/A-LL. Deployment of this cement allows for significant embodied carbon footprint reduction in bridge structures averaging 12% in comparison for CEM I solutions. Limestone as a major non-clinker cement’s constituent is characterized by a number of additional properties in cement composites, which were also presented in this article. In the near future, with the limited availability of good quality other popular ingredients of cement (S, V), limestone and cement based on it may become a natural choice for reduction of carbon footprint in concrete.
10
Content available remote Wapień w składzie kompozytów cementowych
PL
W artykule przedstawiono wpływ wapienia (LL) na cechy fizyczne i chemiczne stwardniałego zaczynu cementowego. Przeanalizowano właściwości cementu portlandzkiego wapiennego CEM II/A, B-LL oraz cementu portlandzkiego wieloskładnikowego CEM II/A, B-M (S, LL) i CEM II/A, B (V-LL). Podkreślono znaczenie wielkości wskaźnika w/c w przypadku poziomu wytrzymałości i trwałości kompozytów cementowych, w których głównym składnikiem jest wapień (LL). Z tego względu domieszki chemiczne mają istotną rolę w kształtowaniu właściwości betonu wykonanego z cementu zawierającego wapień.
EN
The article presents the influence of limestone (LL) on the physical and chemical properties of hardened cement paste. The properties of the Portland limestone cement CEM II/A, B-LL and the Portland composite cements CEM II/A, B-M (S, LL) and CEM II/A, B (V-LL) were analysed. The importance of the w/c-ratio for the level of strength and durability of cement composites made of cement containing limestone (LL) as the main component was emphasized. For this reason, chemical admixtures play an important role in shaping the properties of concrete with cement containing limestone.
11
Content available remote Renowacja i konserwacja tradycyjnych budynków z lokalnego kamienia wapiennego
PL
W Kotlinie Kolskiej i w jej otoczeniu do lat 60. XX wieku rozwijało się budownictwo z lokalnego kamienia wapiennego nietypowe dla nizinnej części Polski. Efektem było zaistnienie specyfiki architektonicznej i konstrukcyjnej w tutejszym budownictwie, przede wszystkim wiejskim. Ostatnia dekada przyniosła wyraźne zmniejszenie liczby budynków wykazujących oryginalne regionalne cechy. Jako najistotniejszą przyczynę wskazano prowadzenie prac remontowych i modernizacyjnych z zastosowaniem współczesnych materiałów budowlanych i technologii.
EN
Until the 1960s, the construction of local limestone, unusual for the lowland part of Poland, developed in the Koło Valley and its surroundings. The result was the occurrence of architectural and construction specificity in the local construction, especially in the countryside. The last decade has brought a noticeable reduction in the number of buildings exhibiting original features. The most important reason was renovation and modernization works with the use of modern building materials and technologies without any attempts to maintain their regional character.
EN
The objective of the present work was to evaluate the hydrodynamic behaviour of a stratified bed filtration column consisting of 4 cm of sand and 2 cm of limestone to remove turbidity and measuring the head loss through the filter in several runs. In this study, two types of sand were used as filtering bed material, one fine and one medium. Crushed limestone was also available. These materials were characterized to determine the average particle diameter, porosity, and permeability coefficient. These were respectively 1.7∙10-4 m, 336.96 and 0.68 m∙day-1 for fine sand, 3.3∙10-1 m, 654.24 and 2.59 m∙day-1 for the medium sand and 1.26∙10-3 m, 388.8 and 8.64 m∙day-1 for crushed limestone. Using these materials, hydrodynamic analyses were carried out using clean water under rapid filtration conditions. In these analyses, different filtration rates were determined to be used in each experiment. Once the filtration rates were determined, the filtration analysis was performed with synthetic turbid water prepared at 8 NTU using tap water and bentonite. From the results obtained, a predictive model was developed based on total head losses for the evaluated filter, maintaining the rapid filtration condition. As a result, a turbidity removal efficiency of 97.7% was obtained with a total head loss of 17.8 cm at a filtration rate of 153 m·day-1 . The developed model predicted head loss as a function of operating time, filtration rate, and filter depth to maximise turbidity removal. The model showed excellent prediction accuracy with R2 of 0.9999, which indicates that the model predictions are not biased. It was concluded that, due to the porosity of these materials, a stratified bed of sedimentary rocks has a great potential to be used in surface water filtration processes, which implies that it could be used at the rural community level as a form of water treatment, since the material is a readily available, maintenance is simple and low cost, and installation and operation are effortless.
PL
Przedstawiono badania wpływu mączki, uzyskanej ze skorupek jaj kurzych oraz z wapienia, na właściwości reologiczne zaczynów cementowych. Mączki dodano do cementu portlandzkiego CEM I 42,5 R, w ilości 30%. Stwierdzono większe granice płynięcia i lepkości plastyczne dla zaczynów z cementów z dodatkiem mączki ze skorupek jaj kurzych, od zaczynów cementowych, z dodatkiem mączki z wapienia. Przyczyną jest wpływ budowy błonki jajka kurzego. Chłonąca wodę i pęczniejąca w zaczynie cementowym błonka, powoduje wzrost lepkości oraz zwiększenie tiksotropii w wyniku łączenia się cząstek, w porównaniu z klasycznym zaczynem oraz zaczynem z dodatkiem mączki z wapienia.
EN
The paper presents the effect of the powders obtained from eggshells and limestone on the rheological properties of cement pastes. Both powders were added to Portland cement CEM I 42.5 R, 30% by mass. The higher yield stress and plastic viscosity of the cement pastes prepared with the addition of eggshell powder, compared to the cement pastes made with limestone powder, were explained by the influence of the eggshell membrane and its chemical structure. The membrane, which absorbs water and expands in the cement paste, is causing an increase in rheological parameters. The membrane, which absorbs water and swells in the cement paste, causes an increase in viscosity and thixotropy compared to the neat cement slurry and slurry with limestone meal added as a result of particle bonding.
EN
The article presents the problem of selecting the correct type of limestone for producing paving stones used to renovate the surface of Mariacki Square in Krakow. Due to using up local limestone deposits, imported limestones began to be used. The first one was a Turkish limestone with the trade name Lotus Beige. Despite substantial physical and mechanical parameters (compressive strength 134 MPa, water absorption 0.26%), after several years of use, the paving stone cracked and, as a result, fell apart into smaller fragments. Hauteville limestone from France has been selected for the following reconstruction of the surface. This limestone in the air-dry state was characterised by even higher parameters, i.e. compressive strength of 157 MPa, flexural strength at 16.9 MPa, Bohme Abrasion test at 15275 mm3, and water absorption at 0.23%. The tests also showed absolute frost resistance and high resistance to thermal shock. Unfortunately, after several years of using the surface of Mariacki Square, cracks and flaking of the rock material have been observed in terms of some paving stones. These cracks appeared within the so-called stylolite seams, which are a natural feature of limestone. Despite a very strict selection of materials, unfortunately, problems with the surface’s durability could not be avoided.
EN
Purpose: The aim of the research was to describe the properties and methods of using limestone for desulfurization of flue gases and to analyse the process of fluidized bed comminution and the influence of selected parameters and stand modification on quality of product of fluidized bed comminution. Design/methodology/approach: Tests of the grinding process on the fluidized bed were carried out using a modified fluid bed mill for operational variable parameters and their results were compared with the results received before modification. The modification of the test stand consisted of increasing the height of the grinding chamber, which ensured an increase in the volume of the fluidized layer where the grinding process takes place. Findings: Main parameters that determined the effects of comminution in the analyzed case were: overpressure of working air and the rotor speed of the classifier. The introduction of the modifications of the test stand ensured an increase in the volume of the fluidized layer in which the grinding process takes place. As well as a greater gravitational classification, which caused larger grains to be stopped in the grinding chamber and shift of characteristics of grain compositions towards finer grains. Research limitations/implications: It is assumed that the diameter of sorbent grains used in the fluidized bed can not exceed 6 mm. The granularity of the offered sorbents ranges from 0.1 mm to 1.2 mm. The quality of the desulfurization process depends on the overall granulation of used sorbent grains. Practical implications: Appropriately selected sorbent grains used in wet and dry flue gas desulphurisation plants ensure improved efficiency of the desulphurisation process and lower operating costs of the installation. Originality/value: Thanks to the comminution method used, a sorbent is obtained without impurities and with an increased specific surface, which can be used in fluidized bed boilers.
EN
Calcium Sulfoaluminate cements (CSA) may be an alternative to Portland cements due to their very high early strength and more environmentally friendly production technology, however they are characterized by a short setting time and high cost. A possible solution to these problems is to mix CSA cement with other binders or additives. In order to test this possibility, CSA cement was mixed with Portland cement and limestone in the amount of 10, 20 and 30 wt. %. A hydration heat test was carried out in the first 72 hours after the components were mixed, measured were compressive and flexural strength after 1, 2, 7 and 28 days, and rheological properties, including early shrinkage. A negative interaction between CSA and CEM I 42.5R was observed, leading to deterioration of mechanical properties of the mortars. The study did not indicate a similar negative interaction between CSA cement and limestone.
PL
Potrzeba zmniejszenia śladu węglowego stała się jednym z głównych problemów przemysłu cementowego ze względu na wysoką produkcję dwutlenku węgla w procesie spalania klinkieru portlandzkiego, która wynosi od 0,6 do 0,8 tony CO2 na 1 tonę klinkieru portlandzkiego. Sytuacja ta stwarza zapotrzebowanie na mniej popularne klinkiery, takie jak cement CSA (cement wapniowo siarczanoglinianowy). Cement CSA charakteryzuje się krótkim czasem wiązania, wysoką wytrzymałością początkową i niskim skurczem, a podczas jego produkcji emitowane jest mniej CO2 w porównaniu z klinkierem OPC. Jednakże wysoki koszt cementu CSA zachęca do mieszania CSA z innymi, tańszymi spoiwami lub nieklinkierowymi składnikami głównymi cementu. Celem prezentowanych badań było zatem zbadanie właściwości zapraw z użyciem cementu CSA zmieszanego ze zwykłym cementem portlandzkim CEM I 42,5R (OPC) lub wapieniem w ilości 10, 20 i 30% masy cementowej. Badano następujące właściwości: ciepło hydratacji w pierwszych 72 h od połączenia cementu z wodą, wczesny skurcz zaprawy w pierwszych 24 h, właściwości reologiczne, czyli granicę plastyczności i lepkość plastyczną świeżej zaprawy, a także wytrzymałość na ściskanie i zginanie po 1, 2, 3, 7 i 28 dniach. Zaprawy przygotowano na bazie normowej zaprawy wg EN 196-1, zawierającej 450g cementu, 1350g piasku normowego i o stosunku w/c wynoszącym 0,5. Ze względów technicznych stosunek w/c został zmieniony dla pomiarów reologicznych na 0,6.
EN
The current work presents the results of seven sorbent samples investigated with respect to SO2 capture. The sorbents’ reactivity and capacity indexes were determined, and the tests were carried out in accordance with the ‘classical’ procedure for limestone sorbents. The reactivity indexes (RIs) of the tested samples were in the range of 2.57 and 3.55 (mol Ca)/(mol S), while the absolute sorption coefficients as determined by the capacity index (CI) varied between 87.9 and 120.6 (g S)/(kg of sorbent). Porosimetric analysis was also carried out and the specific surface area of the samples was found to be between 0.2 and 1.7 m2 /g. The number of micro-, meso- and macro-pores in individual samples was determined from the corresponding pore size distribution histograms, and the values of sorbent RIs and CIs were correlated with the samples’ total porosity and specific surface.
18
Content available remote Cementy portlandzkie wieloskładnikowe żużlowo-wapienne (S-LL)
PL
Właściwości fizykochemiczne cementów żużlowo-wapiennych są na zbliżonym poziomie do właściwości cementu portlandzkiego żużlowego. Zaobserwowano przy tym korzystny wpływ udziału wapienia w składzie cementu na wytrzymałość na ściskanie zapraw cementowych, szczególnie przy obniżonym współczynniku w/c. W ocenie właściwości betonu szczególną uwagę zwraca efekt doszczelnienia struktury matrycy cementowej, przejawiający się zwiększeniem odporności na wnikanie mediów ciekłych i gazowych w głąb betonu (ograniczenie głębokości penetracji wody pod ciśnieniem oraz przenikalności jonów chlorkowych). Możliwe jest uzyskanie betonów klasy C30/37. Natomiast zapewnienie mrozoodporności betonu z cementów portlandzkich wieloskładnikowych (S-LL) nie jest łatwe do osiągnięcia, pomimo prawidłowego napowietrzenia mieszanki betonowej.
EN
The physicochemical properties of the composite slag-limestone cements are similar to those of the Portland slag cement. Additionally a favorable effect of limestone on the compressive strength of cement mortars was observed, especially at a reduced w/c ratio. While assessing the properties of concrete, particular attention is paid to the effect of sealing the structure of the cement matrix, which is manifested in the increased resistance to media penetration into the concrete (limiting the depth of water penetration under pressure and the permeability of chloride ions). It is possible to obtain concretes of C 30/37 class, while ensuring the frost resistance of concrete frost resistance of concrete with Portland composite cement (S-LL) seems to be quite challenging to achieve despite the proper aeration of concrete.
PL
Województwo świętokrzyskie znane jest ze swoich złóż kruszyw. Jednym z wyróżniających się zakładów górniczych jest ten działający od wielu lat w Budach. Tym razem po kopalni oprowadzi nas jej kierownik Marek Zając, który opowie nie tylko o prehistorycznej przeszłości tych terenów, ale także o tym, jakie są plany firmy na przyszłość.
EN
Three-dimensional modeling of the limestone and dolomite distribution in an Upper Permian (Zechstein) stromatolite-bryozoan reef, ~500 m in diameter and 35 m thick (77 borehole cores, 172 data points), shows that dolomite occurs as laterally and vertically discontinuous intervals. The prevailing mineral phases are near-stoichiometric dolomite and Mg-free calcite (370 XRD and 274 XRF analyses). Both δ13C and δ18O (526 analyses) show a spread of ~10‰ and co-vary with the mineralogy; the heaviest dolomite and calcite δ13C differ by ~1.5‰. Diagenetic modifications caused by flowing meteoric fluids could account for the observed “inverted J” trend of stable and the radiogenic signature of 87Sr/86Sr (23 analyses), but neither vertical nor horizontal gradients occur in the reef modeled. Because the dolomite geometries are incompatible with those predicted by fluid flow models, and the limestone-dolomite difference in δ13C overlaps estimates of isotope fractionation associated with Mg content, the dolomite studied was a depositional Very High Mg Calcite recrystallized to dolomite in a semi-closed diagenetic system rather than a Low Mg Calcite transformed by a dolomitization process. The isotope pattern suggests biogenic fractionation and/or loss of heavy stable C and O and light Sr isotopes during diagenesis.
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