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1

Geospatial analysis of the sand market as a factor in selecting the location of a plant producing dry mortar mixtures

Machniak Łukasz, Łochańska Dorota

Materiały Budowlane

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2025

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nr 8

89--100

EN

The purpose of the study was to apply GIS to analyze sand availability in selecting the location of a dry mix plant. Geospatial analysis showed that only 18% of the country’s area met the minimum assumed location criteria. This proves that the sand availability factor can be important in site selection together with other factors, i.e.: availability of transportation infrastructure, demand for final products, competitive analysis, as well as land use, regulatory and environmental aspects.

PL

Artykuł dotyczy zastosowania GIS do analizy dostępności piasku przy wyborze lokalizacji zakładu produkcji suchych mieszanek. Analiza geoprzestrzenna wykazała, że tylko 18% powierzchni kraju spełnia minimalne założone kryteria lokalizacyjne. Dowodzi to, że czynnik dostępności piasku może mieć istotne znaczenie w doborze lokalizacji wspólnie z innymi czynnikami, tj. dostępność infrastruktury transportowej, popyt na produkty końcowe, analiza konkurencji, a także aspekty związane z zagospodarowaniem przestrzennym, regulacjami prawnymi oraz ochroną środowiska.

2

Application of a geochemical modeling code to the analysis of the phase composition of silicate bricks

Stępień Anna

Materiały Budowlane

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2025

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nr 11

180--185

EN

This paper discusses glass recycling and the use of recycled glass in silicate bricks as a sustainable waste management option in construction. The proposed modification involved replacing quartz sand with recycled glass sand in the silicate mass at a rate of 10-90%, shortening of the autoclaving time, and using the GEMS-PSI software to analyze the phase composition and design of the bricks. Laboratory production involved the production of 5×5×5 cm blocks, and the production process replicated the industrial process.

PL

Artykuł dotyczy recyklingu szkła, zastosowania recyklatu w cegłach silikatowych jako wariantu zrównoważonej gospodarki odpadami w budownictwie. Propozycja modyfikacji polegała na zastąpieniu piasku kwarcowego w masie silikatowej piaskiem szklanym z recyklingu w ilości 10-90%, skróceniu czasu autoklawizacji i zastosowaniu programu GEMS-PSI do analizy składu fazowego oraz projektowania cegieł. Produkcja laboratoryjna obejmowała wykonanie bloczków o wymiarach 5×5×5 cm, a proces produkcji był odwzorowaniem procesu w warunkach przemysłowych.

3

Optimization of time for portable X-ray fluorescence analysis across different substrates

Yatsenko Vitalii, Datsko Oksana, Butenko Andrii, Kovalenko Ihor, Bakumenko Olha

Journal of Ecological Engineering

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2025

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Vol. 26, nr 5

139--147

EN

The soil environment plays a pivotal role in ecosystem sustainability, but industrialization and intensive agriculture contribute to heavy metal contamination. Portable X-ray fluorescence (pXRF) has emerged as an efficient tool for detecting heavy metal concentrations in soils and sands. This study evaluates the influence of measurement duration on the accuracy of pXRF results across soil and sand substrates. Measurements were performed using a Thermo Scientific Niton XL2 device on meticulously prepared samples with durations ranging from 5 to 220 s. Results demonstrated that optimal analysis times varied between substrates: 180–220 s for soils and 140 s for sands yielded stable and accurate data. Prolonged durations improved the statistical reliability of concentrations, particularly for trace elements like nickel and arsenic, which required extended times for detection. Findings emphasize the importance of calibrating analysis duration to enhance pXRF accuracy and applicability in environmental and agricultural research.

4

Effect of Input Parameters on The Mechanical Properties of Green Sand Mould

Modi Arpit H., Acharya Shailee G.

Archives of Foundry Engineering

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2025

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Vol. 25, iss. 1

129--137

EN

Among all the methods of metal forming, green sand moulding is the most commonly used method due to its low cost and high speed of work. Main constituents of green sand mould are sand, water, coal dust and binder. Mechanical properties like permeability, green compressive strength, mould hardness, compactibility and moisture content of green sand directly affects the quality of castings produced. This research is done to investigate the effect of input parameters (bentonite, garcolap powder, water) on the mechanical properties of green sand mould. Three levels of each input parameter were considered, and the experiments were designed using design expert software version-13. The regression analysis was performed on the experimental results using Minitab software version-21 to evaluate the effect of bentonite, garcolap powder and water on mechanical properties of green sand mould. Twenty experiments were designed by the software. Values of mechanical properties of green sand like compactibility, permeability, mould hardness, green compressive strength and moisture content were measured by performing experiments on specimen prepared from green sand in accordance with the IS: 1918-1966. Measured values were compared with the standard for validation. Results of this research clearly indicate that bentonite is the only input parameter which has the highest effect on mechanical properties of green sand mould.

5

Piasek jako magazyn energii?

Skrzek Kinga

Nowa Energia

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2024

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nr 2

34--38

PL

Magazyny piaskowe, wykorzystujące piasek jako medium do przechowywania energii cieplnej, przedstawiają się jako innowacyjne i obiecujące rozwiązanie w dziedzinie magazynowania energii. Artykuł eksploruje różnorodne aspekty tej technologii, od jej podstawowych mechanizmów działania, poprzez zalety i wyzwania, aż po przyszłe kierunki rozwoju i potencjał skalowania. Dzięki niskim kosztom inicjalnym, szerokiej dostępności surowców i możliwości zastosowania w różnych sektorach - magazyny piaskowe stanowią atrakcyjną alternatywę dla tradycyjnych metod magazynowania energii.

6

Nie chować głowy, czyli o tym, jak piasek może pomóc z magazynowaniem energii

Pater Michał

Kierunek Surowce

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2024

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nr 2

24--26

PL

Magazyny piaskowe mają potencjał do tego, by znacząco przyczynić się do zrównoważonego rozwoju energetycznego, oferując innowacyjne i ekonomiczne rozwiązania do przechowywania energii. Ich prostota i dostępność czynią je atrakcyjnymi dla różnych zastosowań: od przemysłowych po komercyjne.

7

Growth and Development of Rhizophora spp. Seedlings on Different Substrates and Insertion Level in the Wouri Estuary Mangrove (Douala, Cameroon)

Boubakary Boubakary, Léopold Essomè-Koum Guillaume, Flavien Kottè-Mapoko Ernest, Maxemilie Ngo-Massou Vanessa, Laurant Nyamsi-Moussian, Alphonse Konango-Samè, Michel Emanè Jean, Din Ndongo

Journal of Ecological Engineering

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2024

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Vol. 25, nr 4

96--110

EN

Mangroves are threatened with extinction worldwide. Many mangrove reforestation projects have been developed, but very few have achieved their restoration objectives. With the ambitions to contribute for rehabilitation of mangrove ecosystems, the aim of this study was to assess the effects of substrate composition and level of insertion on the growth and development of Rhizophora seedlings in nurseries. The experiment was conducted in a semilighted nursery set up in situ. Rhizophora propagules were reared on three types of mangrove substrates (type 1:75% of mud and 25% of sand; type 2:50% of mud and 50% of sand, and type 3:25% of mud and 75% of sand) with different levels of insertion (at ¼; ½ and ¾). Seedling heights and diameters were recorded, as well as the time of appearance of the first leaves and the variation of number of leaves. The greatest average height (40.2±7.48 cm) and the highest mean diameter (1.2±0.01 cm) were obtained for the substrate composed of 75% mud and 25% sand. The best growth and development of seedlings were recorded on the substrate type 1 with an insertion at ¼. Seedling production at ¼ insertion of substrate type 1 appeared the most effective combination. The production of Rhizophora seedlings on the substrate combining 25% Sand and 75% Mud with an insertion level at 1/4 seems to be the best method for the complete restoration and rehabilitation of the mangrove ecosystem of the Wouri estuary.

8

Effects of Different Growing Media on Propagation of the Cassava Mosaic Disease-Resistant HN5 Variety in Tunnel Greenhouse

Minh Nguyen Van, Huu Nguyen Ngoc, Loc Nguyen Van

Journal of Ecological Engineering

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2024

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Vol. 25, nr 10

361--367

EN

Researching rapid multiplication techniques for mosaic-resistant cassava in tunnel greenhouses is crucial for ensuring food security and sustainable agriculture. Our previous findings indicated that a combination of 50% shading and 70–75% humidity significantly enhanced the formation of shoots and growth of cassava seedlings in a tunnel greenhouse. The current study examines the impact of different substrate compositions on cassava propagation. The experiments were designed as split plots with three replicates and four formulas including CTRL: 100% sand with a thickness of 40 cm; CT-1: 100% sand with a thickness of 30 cm; CT-2: 60% sand and 40% gravel with a thickness of 40 cm; CT-3: 70% sand and 30% gravel with a thickness of 40 cm; and CT-4: 50% sand and 50% gravel with a thickness of 40 cm. The results demonstrated that CT-3 yielded the highest shoot formation rate and growth of cassava seedlings, suggesting that the combination of sand (70%) and gravel (30%) at a thickness of 40 cm provide the most favorable conditions for cassava propagation in tunnel greenhouse conditions.

9

Rheological and mechanical behavior study of eco-friendly cement mortar made with marble powder

Chahour Kahina, Mechakra Hamza, Safi Brahim, Dehbi Nacera-Melissa, Chaibet Cylia

International Journal of Applied Mechanics and Engineering

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2024

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Vol. 29, no. 1

19--35

EN

The work aim is to investigate the rheological and mechanical behavior of eco-friendly mortar made with marble powder. Marble have used as sand by total substitution of natural sand and as additional materials by partial substitution of cement. Firstly, rheological tests were carried out on the cement pastes in order to studying the effect of cement substitution by marble powder on the rheological behavior. Secondly, our study is devoted to evaluate the mechanical performances (flexural strength, compressive strength, mechanical behavior and ultrasonic pulse velocity) of a fluid mortar such as the case of the self-compacting mortars elaborated with the marble powder as addition materials and as a sand. The mechanical test results show that a significantly improved of compressive strength and mechanical behavior of an ecological cement mortar made with marble waste as a natural sand. However, marble-based mortars with 100% of marble sand have given a mechanical strength similar to that obtained by control cement mortar (100% natural sand). It was also noted that it can be obtained an ecological cement mortar made with 30% of marble powder as an addition supplementary materials. This leads to a reduction in cement consumption cad a reduction in CO2 gas emissions caused by cement production.

10

Comparative Study of Two Types of Sand Used for Wastewater Treatment (Case of Algerian Sahara)

Djihad Rezagui, Hafida Driz, Lamia Cherif, Radia Gherissi

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 7

196--209

EN

Filtration is one of the oldest techniques and by far the most widely applied in water treatment operations. It is considered one of the most effective methods for purifying waste water. Sand filtration consists of passing water loaded with suspended and colloidal matter through a filtering material in order to clarify it. In Ouargla region, wastewater is evacuated in a closed system without any treatment, which presents a natural risk to public health and endangers the sustainability of agriculture and the environment. In this modest study, two sand samples of different grain size and shape were used as the filter bed. Several filters were constructed using two types of sand with the same dimensions and different characteristics. The filter was exposed to clogging during the operation, which is prejudicial to the filtration process. For this reason, our study aims to see the influence of the type of sand on this process and analyze the phenomenon of filter clogging: the causes of its appearance, its types and their location as well as the parameters governing it. The most important thing is to evaluate the quantity of organic matter deposited in the different layers of the filter, and see its distribution as a function of time over the whole the depth of the filters. This study shows that the sand filter is subjected to progressive clogging. This clogging is classified into three fragments: mechanical, physical and organic. The study showed that the finer the granulometry, the greater the accumulation of organic matter. From the third week onwards, the formation of a biological film has been observed, which allows for very thorough purification. In other words, a quantity of suspended matter settles as the biomass degrades the organic matter.

11

Bearing Capacity Evaluation of Shallow Foundations on Stabilized Layered Soil using ABAQUS

Bhardwaj Avinash, Sharma Ravi Kumar

Studia Geotechnica et Mechanica

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2023

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Vol. 45, nr 1

55--71

EN

In this paper, the finite element method (FEM) is applied to calculate the bearing capacity of two footings having the aspect ratio L/B (where L and B are the length and width of the footing, respectively) equal to 1, 2 resting on one-layer and two-layer soil. Soil profile contains two soil types including sand and clay. The soil strip is 500mm × 500mm × 350mm; however, only a quarter of the model (250mm × 250mm × 350mm) is examined in the study. Two primary situations are investigated in this study. In the first situation, the one-layer system is supposed to be sandy soil with footing overlays on medium-dense sand. The soft clay/stabilized clayey layer is supposed to be on top of the sandy soil in the second condition, with the footing resting on top of the soft clay/stabilized clay. The influence of layer thickness, aspect ratio, and material property on the bearing capacity value and footing failure mechanism is studied for eight different combinations of layered soil. The bearing capacity for a one-layer case is also estimated, and it agrees well with Vesic (1973), Hansen (1970), and Terzaghi's (1943) equations. The bearing capacity of footings is observed to decline when the height of unstabilized clayey soil increases, and it increases when clayey soil is stabilized with molasses, waste foundry sand, and lime alone and in combination with each other.

12

Determination of the Degradation Degree of Pasture Lands in the West Kazakhstan Region Based on Monitoring Using Geoinformation Technologies

Yesmagulova Bayan Zhumabaevna, Assetova Assem Yurievna, Tassanova Zhadyra Baizhanovna, Zhildikbaeva Aizhan Naskenovna, Molzhigitova Dinara Kumarbekovna

Journal of Ecological Engineering

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2023

|

Vol. 24, nr 1

179--187

EN

Land degradation, including pasture lands is one of the global problems. Currently, one of the most urgent problems of the West Kazakhstan region is the preservation and restoration of the vegetation cover of pasture lands. To date, large areas of the region have been occupied by agricultural land. Several main reasons negatively affect agriculture, one of which is land degradation associated with anthropogenic impact in terms of the irrationality of land use. Thus, to preserve the biodiversity of the pastures of the West Kazakhstan region, it is necessary to fully study the projective cover of the vegetation, determine the dominant plant species, and also monitor the condition of pastures to prevent land degradation on time by conducting land and forest improvement activities. The study aimed to carry out a phyto-ecological assessment of degraded pastures of the Karatobinsky district of the West Kazakhstan region using geoinformation technologies and field study results. The paper presents the results of desktop decoding of high-resolution satellite images and ecological profiling of the studied territories. Decoding features of landscape types allowed making a preliminary map of landscape contours. The use of this technique makes it possible to monitor the condition of degraded pasture lands in a short time and justify the organization of pastures with a regulated grazing system in the study area.

13

Testing and Evaluation of Physical and Chemical Properties of Waste from Desanding

Czop Monika, Petryk Agnieszka, Balcerzak Luzia, Jamry Agata, Kopiec Weronika, Nowak Katarzyna, Piwowarczyk Marta, Zackiewicz Weronika

Inżynieria Mineralna

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2023

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no. 2, vol. 2

129--134

EN

The study concerns evaluating the physical and chemical properties of sand from sand separators of wastewater treatment plants in terms of requirements for construction aggregates. Thus, an analysis of the physical properties of sand was carried out, i.e. its moisture content, bulk density, and grain density, as well as an analysis of the chemical composition of sand. The intention of the research is to find an alternative to the dwindling supply of this type of raw material, which is essential for the construction sector. It is currently estimated that within 20 years there will be a shortage of sand of suitable quality for use in construction. The article presents the results of physicochemical tests and leachability of selected harmful substances (P, F, N-NH4 +, Cl, SO4 2-) and heavy metals (Ba, Zn, Cu, Pb, Cd, Cr, Co, Fe, Ni) from waste from desanding

PL

W artykule dokonano oceny właściwości fizykochemicznych piasku z piaskowników oczyszczalni ścieków pod kątem wymagań stawianych kruszywom budowlanym. W związku z tym przeprowadzono analizę właściwości fizycznych piasku: wilgotność, gęstość nasypową, a także analizę składu chemicznego piasku i poziom wymywalności substancji szkodliwych oraz metali ciężkich. Celem badań było znalezienie alternatywy dla malejącej zasobów tego cennego surowca, niezbędnego dla sektora budowlanego. Obecnie szacuje się, że w ciągu 20 lat zabraknie piasku odpowiedniej jakości do wykorzystania w budownictwie. W artykule przedstawiono wyniki badań fizykochemicznych oraz wymywalności wybranych substancji szkodliwych (P, F, N-NH4 +, Cl, SO4 2-) i metali ciężkich (Ba, Zn, Cu, Pb, Cd, Cr, Co, Fe, Ni) z zawartości piaskownika.

14

Review of possibilities of using sandy waste obtained in wastewater treatment plants as an alternative raw material in construction

Kostrzewa Jacek, Popielski Paweł, Dąbska Agnieszka

Gospodarka Materiałowa i Logistyka

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2023

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nr 3

25--37

EN

Sand is a globally mined natural resource. It is applied, among others, in construction, because sand is one of the main components of concrete mixtures and a material used in earthworks. The aim of the manuscript is to organize the state of knowledge regarding the management of sandy waste generated in wastewater treatment plants and to indicate the possibilities of using this waste as an alternative raw material in construction applications. The main thesis is the claim that sand recovered in wastewater treatment plants, perceived as waste, can be an alternative for the global economy to obtain a significant amount of raw material for various uses in construction and to replace natural raw materials extracted for industry. The paper presents data on natural sand resources and its use, the effects of uncontrolled exploitation of the worlds sand resources and the potential of the Polish sand resource base. Particular attention was paid to the review of the possibilities of using sandy waste generated in wastewater treatment plants as an alternative raw material for natural sand resources. The practical applications of sand obtained in the processes used in wastewater treatment plants were also presented.

PL

Piasek jest globalnie wydobywanym zasobem naturalnym. Stosuje się go m.in. w budownictwie, ponieważ piasek jest jednym z głównych składników mieszanek betonowych oraz materiałem wykorzystywanym w robotach ziemnych. Celem artykułu jest uporządkowanie stanu wiedzy dotyczącego zagospodarowania odpadów piaszczystych powstających w oczyszczalniach ścieków i wskazanie możliwości wykorzystania tych odpadów jako surowca alternatywnego w zastosowaniach budowlanych. Główną tezę stanowi twierdzenie, że piasek odzyskiwany w oczyszczalniach ścieków, postrzegany jako odpad, może być alternatywą dla światowej gospodarki na pozyskanie znacznej ilości surowca do różnych zastosowań w budownictwie i zastąpienia nim surowców naturalnych wydobywanych dla przemysłu. W pracy przedstawiono dane dotyczące zasobów piasku naturalnego i jego wykorzystania, skutki niekontrolowanej eksploatacji światowych zasobów piasku oraz potencjał polskiej bazy zasobowej piasku. Szczególną uwagę poświęcono przeglądowi możliwości wykorzystania odpadów piaszczystych powstających w oczyszczalniach ścieków jako alternatywnego surowca dla piasku naturalnego. Przedstawiono również dotychczasowe, praktyczne zastosowania piasku uzyskanego w procesach stosowanych w oczyszczalniach ścieków.

15

Study the Effects of Using Different Water Types on the Mechanical Properties of Concrete

Fadil Sanad Aldeen, Al Kindi Ghayda Y., Tobeia Sameh B.

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 1

175--184

EN

The issue of water sustainability is a major topic due to the lack of water sources and the scarcity of drinking water, so the search for alternatives began. In this paper, the effect of using three water sources will be studied (the tap water (as control reference mix.), the Tigris River, and the Pepsi Company factory). To study the physical and chemical properties, and the effect of this water on the concrete mixture, and for each source the concrete mixture was placed in cube molds and cylinders. Put the concrete mixture in a water basin for curing. Compression and splitting tests are performed at intervals of (7-28-90) days to evaluate these mixtures. From the results it was found that the compressive and splitting strength of concrete for tap water, Tigris River and Pepsi factory, which was recorded at the age of 7 days, the compressive strength of cubes was an average of 18.5 MPa, 19 MPa and 13 and the splitting strength was an average of 1.5 MPa and 1.4 MPa and 0.5 MPa, respectively, at the age of 28 days, which were recorded at 32.1 MPa, 28 MPa, and 16.4 MPa, respectively, and the splitting strength was 3 MPa, and 2.7 MPa, and 1.5 MPa, respectively, and at 90 days they were 36 MPa, 32 MPa, and 18 MPa, respectively, and the splitting strength was 3.2 MPa, 3 MPa, and 1.7 MPa respectively also was observed a decrease in compressive strength and splitting by more than 40% for Pepsi Baghdad company factory wastewater samples. Finally, the drinking water and the water of the Tigris River was suitable for making concrete mixtures.

16

Environmental Assessment of a Unique Filtration Process for Treatment of Polluted Storm Water

Al-Khalaf Safaa K. Hashim, Al-Ridah Zaid Abed, Shlash Marwah Abdullah, Naje Ahmed Samir

Ecological Engineering & Environmental Technology

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2023

|

Vol. 24, iss. 1

116--124

EN

As a result of poor human activities, storm water is now contaminated, notably in the Middle East. The filtering process is a physical separation with no chemical reactions occurring throughout the operation. The goal of this research is to use three distinct types of filters to improve the quality of storm water: sand, sand with granular activated carbon (GAC), and sand with cotton. Before and after treatment, the pH, turbidity, electric conductivity, TDS, and temperature of storm water are all monitored. In addition, the water quality index (WQI) was computed. The parameters of treated storm water varied depending on the filter media used, such as sand (turbidity = 83 NTU, TDS = 585 mg/L, conductivity = 1190 S/cm, pH = 7.1 and temperature =17.8 °C), sand with GAC (turbidity = 12NTU, TDS = 540 mg/L, conductivity = 910 S/cm, pH = 7 and temperature =18 °C) and sand with cotton (turbidity = 6.4 NTU, TDS = 490 mg/L, conductivity = 1090 μS/cm, pH = 7.2 and temperature =17.6 °C). Sand has a treatment efficiency of 63.6 percent, sand with GAC has an efficiency of 84.9 percent, and sand with cotton has an efficiency of 84.2 percent at a flow rate of 0.66 L/min, when WQI is clean. With GAC, it is clear that the dual media filter is the finest special sand.

17

Graphite oxide coated sand composites for efficient removal of calcium ions from hard water: isotherm, kinetics, and adsorption mechanism

Perera W.P.R.T., Premasinghe Niroshan, Fernando W.S.K., Perera P.L.R.A., Sandaruwan Chanaka, Kumarasinghe A.R., Liyanage Janitha A.

Composites Theory and Practice

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2023

|

R. 23, nr 4

209--219

EN

Even if granular media filtration effectively reduces the turbidity of water, its limited surface functionalities and physical properties may constrain its ability to effectively remove critical contaminants from water. In our research, we successfully synthesized a new type of porous material – multiple coated GO/sand (M-GO/S) by integrating ordinary river sand with graphite oxide (GO) for the adsorptive removal of calcium ions in terms of water softening. Prior investigations confirmed it could remove water turbidity and fluoride simultaneously. M-GO/S was characterized using microscopic and spectroscopic techniques. The results indicate the presence of an uneven coating of graphite oxide, and the nanocomposite contains oxygencontaining functional groups. Under given conditions, the M-GO/S nanocomposite demonstrated remarkable efficacy in removing 75% of calcium ions (a higher removal percentage than commercial coal powdered activated carbon) from simulated hard water: pH 8, 5.0 g dosage, 50 mg/L calcium ions, and 20 min contact time. The isotherm and kinetic data revealed that the adsorption mechanism primarily comprises multilayer adsorption by means of a chemical sorption process. The mechanism of the proposed M-GO/S nanocomposite for removing calcium ions from hard water is elucidated using (XPS) analysis. The presence of (-O-Ca-O-) chemical bonds on the surface of the nanocomposite after equilibration with calcium ions suggests the occurrence of chemical interactions between the calcium ions and oxygen-containing functional groups of the M-GO/S. Consequently, the synthesized M-GO/S nanocomposite can be identified as a promising candidate for hard water treatment.

18

Detrital heavy minerals as guides to provenance of Albian arenites of southern extra-Carpathian Poland

Kotowski Jakub, Olszewska-Nejbert Danuta, Nejbert Krzysztof

Acta Geologica Polonica

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2023

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Vol. 73, no. 4

801--832

EN

The potential of heavy minerals as a provenance tracer in Albian arenites of extra-Carpathian Poland was assessed. Studies in this area have focused on various methods based on heavy mineral chemistry that provide an effective tool for reconstructing the provenance of quartz-rich sediments. The previously suggested division of the study area into two domains with different source areas: the western domain – the Miechów area, and the eastern domain – the Lublin area, was based on geochronological (monazite and muscovite dating) and rutile mineral chemical studies. The mineral chemistry of newly examined heavy minerals supports the previously suggested division. The mineral chemistry of detrital tourmaline suggests medium-grade metamorphic rocks as the main source in both domains. Detrital garnet in the western domain shows affiliation to the Góry Sowie Massif, while garnet in the eastern domain was most probably sourced from southern/central Norway. The western domain was most probably fed from rocks of the Bohemian Massif. The main source area for the eastern domain was most probably located in the Baltic Shield. The distinct division of the study area into two domains was caused by the palaeogeography of the region in the Albian and the action of longshore currents in south-eastward and eastward directions.

19

Proposal of concept for structural modelling of hybrid beams

Kożuch Maciej, Skrętkowicz Łukasz

Studia Geotechnica et Mechanica

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2022

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Vol. 44, nr 4

317--332

EN

Investigation on the behaviour of a hybrid beam is presented. Hybrid beam stands for an element with hybrid cross sections. This means sections that consist of steel and concrete parts, connected together with composite dowels, and both are considered for shear flow analysis. In practice, a more general solution may be used for bridges in the form of a beam in which the span sections are hybrid and the support sections are concrete. Recently such a solution has been introduced for bridge engineering in Poland and a new problem with performing a global analysis of hybrid beams was identified. The solution is new itself and requires also a new approach for internal forces determination. Discussion of this problem is made in the paper. Influences of (1) concrete cracking, (2) rheology of concrete and (3) methods of modelling on the redistribution of internal forces are highlighted. On an example of one of the real bridge girder (being currently under design) analysis is made to show how the abovementioned factors are affecting obtained results. Results are analysed and conclusions are presented. As a final step, a new concept of hybrid beam design is proposed. The proposed solution enables a quick and easy engineering approach to perform a static calculation of the considered structure.

20

Behavior of Vertically Confined Square Footing on Reinforced Sand under Centric Inclined Loading

Kirtimayee B., Samadhiya Narendra Kumar

Studia Geotechnica et Mechanica

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2022

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Vol. 44, nr 3

224--238

EN

This study presents the behavior of vertically confined square footing on geogrid-reinforced sand under centric inclined loading through a series of experimental tests. The load was applied at 5°, 10° and 20° angles of inclination with the vertical. The tests were conducted on surface footing, footing with confiner and footing with confiner and horizontal reinforcement configurations subjected to inclined loading. Parametric variations like depth of the confiner (d=1B, 1.5B, 2B), number of geogrid layers (N; varies with variation in depth of confiner), and spacing between horizontal reinforcements (Y=0.25B, 0.5B, 0.75B, 1B) have been investigated at the top surface dimension of confiner (D) as 1.0B, 1.5B and 2.0B (where B is the width of the model footing). Results show that combined effect of confiner and horizontal reinforcement increases the ultimate bearing capacity of footing significantly compared to only confiner for all angle of inclinations. It can also be observed that load bearing capacities decrease with increase in angles of inclination and record the minimum improvement at 20° angle of inclination. Improvement in bearing capacities and reduction in settlement of footing analyzed in terms of bearing capacity ratio (BCR) and settlement reduction factor (SRF) are compared for all footing configurations. To summarize, the test results showed that confiner along with reinforcement can be considered as an economic ground improvement technique for shallow foundations to counter against heavily inclined loading.