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1

Analysis of thermal and moisture properties of materials and drying of frame partitions after short-term dampness

Kosiń Mariusz, Halbiniak Jacek

Materiały Budowlane

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2025

|

nr 10

198--207

EN

The use of frame structures requires the design of partitions with appropriate thermal and moisture properties. The results of material tests (sorption, water absorption, thermal conductivity coefficient) and simulation of partition drying are presented. Laboratory data confirm the high susceptibility of some of the analyzed materials to moisture absorption. Numerical analysis has shown that the partitions do not regain moisture balance even after a dozen or so months.

PL

Zastosowanie konstrukcji szkieletowych wymaga projektowania przegród o odpowiednich właściwościach cieplno-wilgotnościowych. Przedstawiono wyniki badań materiałów (sorpcyjność, nasiąkliwość, współczynnik przewodzenia ciepła) oraz symulację osuszania przegród. Dane laboratoryjne potwierdzają dużą podatność niektórych analizowanych materiałów na pochłanianie wilgoci. Analiza numeryczna wykazała, że przegrody nie odzyskują równowagi wilgotnościowej nawet po kilkunastu miesiącach.

2

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.

3

Method for assessing the hydrate formation from a mixture of natural gas flows of varying degrees of moisture content

Iskandarov Elman Kh., Baghirov Alovsat N., Shikhiyeva Lala M.

Nafta-Gaz

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2024

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R. 80, nr 1

39--44

EN

The article deals with the issues of assessing the conditions of hydrate formation when mixing natural gas flows of various standards. An urgent problem of operation, especially of offshore subsea gas pipelines, is the prediction of the time, place and expected intensity of hydrate formation. Depending on the changing operating mode of the gas pipeline, dispatch service specialists must be able to adjust the process control tactics on their own, as quickly as possible. The predisposition of a particular gas pipeline to hydrate is also important for the dispatching service. Changes in the volumes of gas entering the region under consideration from different sources, due to the constant change in gas production, create the need to mix gases of different standards and pump them into subsea gas pipeline. To avoid hydrate formation, it is important to predict the thermobaric conditions that will be formed in the gas pipeline by considering the characteristics such as a volume in the mixture and the moisture content of the gas. The processes of hydrate formation proceed quickly and if the beginning of the process is overlooked, the problem of significant or complete blockage of the gas pipeline might appear. The paper gives a systematization of the risk of hydrate formation depending on several infrastructural factors – the presence of a preliminary gas drying system and a system for starting and receiving cleaning pistons. A method is proposed for estimating the moisture content and dew point temperature of a natural gas mixture by the condition and the proportion of primary flows. It has been shown that the addition of a small volume of undried gas to the main dried gas significantly increases the risk of hydrate formation. A formula is given for calculations for a mixture of multiple natural gas flows. The advantage of this method is the quick calculations, and the absence of the need for huge mathematical calculations and laboratory studies. This is an important element in the activities of the dispatch service, limited by a lack of time in the process of preventing hydrate formation.

PL

W artykule podjęto problematykę oceny warunków powstawania hydratów podczas mieszania strumieni gazu ziemnego o różnych standardach. Istotnym problemem eksploatacji, zwłaszcza w gazociągach podmorskich, jest określenie czasu, miejsca i przewidywanej intensywności powstawania hydratów. W zależności od zmieniającego się trybu pracy gazociągu specjaliści służb dyspozytorskich muszą potrafić jak najszybciej samodzielnie dostosować taktykę sterowania procesem. Dla służby dyspozytorskiej istotne znaczenie ma także predyspozycja danego gazociągu do powstawania hydratów. Zmiany objętości gazu docierającego do rozpatrywanego regionu z różnych źródeł, w związku z ciągłą zmianą wydobycia gazu, powodują konieczność mieszania gazów o różnych standardach i wtłaczania ich do gazociągu podmorskiego. Aby uniknąć tworzenia się hydratów, istotne jest przewidywanie warunków termobarycznych, jakie będą panować w gazociągu, biorąc pod uwagę takie cechy jak objętość mieszaniny i zawartość wilgoci w gazie. Procesy powstawania hydratów przebiegają szybko i jeśli zostanie przeoczony początek tego procesu, może pojawić się problem znacznego lub całkowitego zablokowania gazociągu. W pracy usystematyzowano ryzyko powstawania hydratów w zależności od kilku czynników infrastrukturalnych – obecności układu wstępnego osuszania gazu oraz układu startu i odbioru tłoków czyszczących. Zaproponowano metodę szacowania zawartości wilgoci i temperatury punktu rosy mieszaniny gazu ziemnego na podstawie stanu i proporcji natężenia przepływów pierwotnych. Wykazano, że dodatek niewielkiej ilości nieosuszonego gazu do głównej partii gazu osuszonego znacznie zwiększa ryzyko powstania hydratów. Podano wzór do obliczeń w przypadku mieszaniny wielu strumieni gazu ziemnego. Zaletą tej metody jest szybkość obliczeń, brak konieczności wykonywania obszernych obliczeń matematycznych i badań laboratoryjnych. Jest to ważny element w działalności służby spedycyjnej, ograniczonej brakiem czasu w procesie zapobiegania tworzeniu się hydratów.

4

Soft soil foundation treatment of hydraulic fill site based on vibration boosting drainage consolidation method

Zhang Wei

Archives of Civil Engineering

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2024

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Vol. 70, nr 3

431--444

EN

Reclamation from the sea is a method of expanding urban area, but it also faces the problem of difficult treatment of soft soil foundation by hydraulic reclamation. Therefore, a soft soil consolidation method that combines vibration pressure boosting drainage and piled-load static pressure stacking is now proposed. To verify the effectiveness of this method, a consolidation test based on soft soil samples was designed and conducted in the study. The test results showed that when the sampling height was 240mm, the overall moisture content of the consolidated soil sample was the highest, 44.3%, and the consolidation effect was the worst. When the sampling height was 140mm, the overall moisture content obtained from the test was the lowest, 43.1%, and the consolidation effect was the best. The displacement of corner 2 and center point at the intersection of the preceding and following periods was greater, with values of 37.1 mm and 39.2 mm, respectively. At this point, the displacement of corner 1 was significantly smaller, at 30.9 mm. In the later loading stage, the slope of the vertical displacement curve significantly increased. When the experimental time reached 7000 min, the mixed method designed in this study had a drainage rate of 0.53 ml/min, which was significantly higher than other traditional methods. The experiment outcomes indicated that the method designed in this study had certain application potential for improving the consolidation effect of soft soil foundation in hydraulic fill sites.

5

Conductive Heat Transfer Prediction of Plain Socks in Wet State

Mansoor Tariq, Hes Lubos, Khalil Amany, Militky Jiri, Tunak Maros, Bajzik Vladimir, Kyosev Yordan

Autex Research Journal

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2022

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Vol. 22, no. 4

391--403

EN

In this study, an algebraic model and its experimental verification was carried out to investigate the effect of moisture content on the heat loss that takes place due to conduction of sock fabrics. The results show that increasing moisture content in the studied socks caused a significant increase in their conductive heat loss. Plain knitted socks with different fiber composition were wetted to a saturated level, and then their moisture content was reduced stepwise. When achieving the required moisture content, the socks samples were characterized by the Alambeta testing instrument for heat transfer. Three different existing modified mathematical models for the thermal conductivity of wet fabrics were used for predicting thermal resistance of socks under wet conditions. The results from both ways are in very good agreement for all the socks at a 95% confidence level. In the above-mentioned models, the prediction of thermal resistance presents newly a combined effect of the real filling coefficient and thermal conductivity of the so-called “wet” polymers instead of dry polymers. With these modifications, the used models predicted the thermal resistance at different moisture levels. Predicted thermal resistance is converted into heat transfer (due to conduction) with a significantly high coefficient of correlation.

6

Moisture management in biochar amended green roofs planted with Ophiopogon japonicus under different irrigation schemes: an integrated experimental and modeling approach

Liu Jiaqin, Garg Ankit, Wang Hao, Huang Shan, Mei Guoxiong

Acta Geophysica

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2022

|

Vol. 70, no 1

373--384

EN

Green roof constantly suffers from the water stress that is developed during prolonged drought seasons. In general, periodical irrigation is required to ensure plant growth and hence serviceability of green roofs. Biochar, a carbon sink material, has been proposed as a substrate amendment in green roofs for enhancing water retention ability of soils. This study aims to conduct an assessment of the irrigation efficiency of green roofs with different biochar additions (0%, 5%, 10%, 15% and 20%; v/v) under sub-tropical climatic conditions. In order to achieve this objective, outdoor monitoring as well as numerical modeling using HYDRUS-1D was conducted. Soil columns mixed with different proportion of biochar were prepared. These columns were subjected to different irrigation schemes (three irrigation frequencies were assessed (i.e., per 3, 7 and 10 days after irrigation or rainfall); moreover, three irrigation amounts for the three irrigation frequencies were considered (i.e., to a fixed amount (FA10mm), to Field water holding capacity (FC) and to Saturated moisture content (SR))). As suggested from the results: (1) Biochar significantly improved water holding capacity and plant available water. 20% biochar delayed the onset of the significant plant wilting phenomenon by approximately 3 days and maintained the maximal transpiration rate of vegetation in the dry period. (2) As compared to irrigation scheme A (irrigation to FC per 7 days), the efficiency of scheme B (irrigation to SR per 10 days) was more vulnerable to the biochar amendment. Moreover, the total irrigation water and days of water stress decreased with an increase in the biochar addition. Furthermore, the combination of 20% biochar and irrigation scheme B could be the optimal choice for maintaining the health of the green roofs and water conservation. The present study helps to obtain desired outcomes in green roofs, e.g., stormwater management, cost reduction as well as providing greening.

7

Zawartość wilgoci, zawartość wody, strata po suszeniu. Cz. 1, Dokładne znaczenie pojęć i sposoby wyznaczania

Schubnell Markus, Caro Cosimo, Kunz Raphael

LAB Laboratoria, Aparatura, Badania

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2021

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R. 26, nr 4

14--20

PL

Woda jest często niepożądanym składnikiem polimerów, substancji farmaceutycznych i produktów spożywczych. Zbyt duża zawartość wody skraca czas przydatności do spożycia ryżu, utrudnia przetwarzanie w produkcji farmaceutycznej (przykładowo formowanie tabletek) i może powodować problemy z jakością produktów z tworzyw sztucznych. W związku z tym bardzo ważnym zadaniem jest wyznaczanie zawartości wody w różnych rodzajach materiałów. Oprócz pojęcia „zawartość wody" często można spotkać się także z pojęciami „zawartość wilgoci” i „strata po suszeniu". W tym artykule (część 1) zajmiemy się omówieniem znaczenia podanych terminów oraz niektórych technik wyznaczania wspomnianych wielkości.

8

Remont ścian w konstrukcji muru pruskiego budynków zabytkowych z dociepleniem od strony wewnętrznej

Orlik-Kożdoń Bożena, Szymanowska-Gwiżdż Agnieszka, Steidl Tomasz

Materiały Budowlane

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2020

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nr 5

20--24

PL

W artykule przedstawiono wybrane zagadnienia docieplania ceglanych ścian zewnętrznych i muru pruskiego od strony wewnętrznej. Zewnętrzne ściany ceglane budynków o charakterze zabytkowym, podobnie jak ściany budynków wzniesione w konstrukcji tzw. muru pruskiego, wymagają zachowania dekoracyjnych walorów fasady. Projektowanie remontu takich przegród wymaga wiedzy z dziedziny budowy takich przegród, ich stanu wilgotnościowego, wpływu stosowanych materiałów i warunków eksploatacji na prognozowane zmiany ilości wody w poszczególnych częściach ściany.

EN

The article presents some of the issues related to the thermal insulation of external brick walls and the Prussian wall from the inside. The external brick walls of historic buildings, like the walls of buildings erected in the so-called technology half-timbered buildings require the decorative qualities of the façade. Designing insulation from the inside of such walls, requires knowledge of the construction of such partitions of their moisture status of the existing part, the impact of thermal insulation material and operating conditions on the projected changes in the amount of water in individual parts of the wall.

9

Efekty działania pustek powietrznych wykonywanych wzdłuż kontrłat

Patoka Krzysztof

Materiały Budowlane

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2020

|

nr 7

48--50

10

Intrinsic cellulosic fiber architecture and their effect on the mechanical properties of hybrid composites

NagarajaGanesh B., Rekha B.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

406--417

EN

This study is mainly focused on the intrinsic fiber parameters and their influence on the mechanical properties of the hybrid composites. Cellulosic fibers are extracted from mesocarp of Cocos nucifera fruit and outer mat of Luffa cylindrica fruit. The inherent fiber parameters such as fiber diameter, lumen diameter, cell wall thickness are observed under light microscope. Micro-fibrillar angle is found using X-ray diffraction technique. Three varieties of hybrid polymer composite samples are fabricated using Cocos nucifera and Luffa cylindrica fibers as reinforcements in the ratio 2:1, 1:1 and 1:2 respectively employing hand layup technique with their combined weight maintained as 30%. Significant response in the Load Vs Deflection curve and mechanical properties of the hybrid composites are found attributing to the difference in the respective weight proportion of the constituent fibers in the hybrid composite system. Results exemplify that the hybrid composite sample comprising Cocos nucifera and Luffa cylindrica fibers in the ratio 1:2 capitulates the maximum flexural strength and impact strength of 31.05 MPa and 14.24 kJ/m2 respectively when compared with other hybrid composites. The reason for the difference in mechanical strength of hybrid composite samples containing two different fibers is found to be related to the built-in architecture and physical characteristics of the constituent fibers. The morphology of the fractured samples are examined and reported. It is concluded that properties of hybrid composites can be tailor made depending upon the requirements either by using the Cocos nucifera fibers to impart ductility or Luffa cylindrica fibers to impart brittleness.

11

Practical application of the microwave oven in the geotechnical laboratory

Jastrzębska Małgorzata

Architecture Civil Engineering Environment

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2019

|

Vol. 12, no. 2

91--104

EN

The main purpose of the paper is to present the usefulness of microwave ovens in the everyday work of geotechnical laboratories. Microwave ovens are commonly used to determine soil moisture and to dry soils that are too moist for other laboratory tests. The activities related to the above processes are not standarized in the majority of countries. The only available guidelines are based on the research projects. For the purpose of this particular research 345 tests have been conducted for moisture content determination for 3 soil types: fine sand (FSa; SP - poorly graded sand), sandy gravel (saGr; GW well graded gravel-sand mixtures) and silty clay (siCl; CH - inorganic clay of high plasticity), using both - standard and microwave methods. The research cycle consisted of 3 different variants which includes soil moisture content, specimen initial mass, number of specimens in microwave oven and their placing. It was established that different factors have impact on the length of the process and it lasted between 2 to 17 minutes. During the heating different undesirable phenomena were observed, e.g., soil explosions or melting and glowing of clay. Based on the above research results this paper introduces guidelines for the soil drying process in the microwave oven (the optimization of the procedure and handling of the dried samples).

12

Znaczenie diagnostyki przy renowacji zawilgoconych obiektów

Garecki M.

Materiały Budowlane

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2018

|

nr 3

36--37

13

Współcześnie stosowane metody osuszania murów

Drozd W.

Materiały Budowlane

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2018

|

nr 3

42--43

PL

Woda we wszystkich stanach skupienia: stałym, ciekłym i gazowym, jest największym wrogiem wielu materiałów i konstrukcji budowlanych, zwłaszcza obiektów murowanych. Istnieją jednak skuteczne metody osuszania, stanowiące jeden z wielu elementów prac renowacyjnych. Przed przystąpieniem do nich najważniejsze jest określenie przyczyn zawilgocenia, a dopiero później zastosowanie metod osuszania. Artykuł porusza problemy zawilgoconych murów. Stanowi też próbę przedstawienia i porównania sposobów ich rozwiązywania.

EN

Water in all states of existence: solid, liquid and gaseous, is the greatest enemy of many building materials and structures, especially masonry. However, there are effective methods of drying them, which are one of the many elements of restoration work. They lead to the removal of excess moisture from the septum. Prior to joining them, it is important to determine the cause of the dampness, and only then the possible methods of drying. This article deals with the problem of damp walls. It attempts to present and compare contemporary methods of drying them.

14

Wpływ wilgoci na trwałość betonu komórkowego

Zając P., Łaskawiec K.

Materiały Budowlane

|

2018

|

nr 1

72--73

PL

Badanie mrozoodporności wg normy PN-EN 15304 często nie pokrywa się z zachowaniem materiału w warunkach eksploatacyjnych. Dotyczy to zazwyczaj ABK o dużej porowatości. W związku z tym przeprowadzono badania porównawcze mrozoodporności ABK wg PN-EN 15304 (wilgotność całkowita) oraz mrozoodporności ABK w stanie wilgotności ok. 30%.

EN

The freeze/thaw resistance testing according to European Standard PN-EN 15304 often does not coincide with behavior of the material under operating conditions. This usually applies to AAC with high porosity. Therefore, comparative research of freeze/thaw resistance AAC: according to PN-EN 15304 (total humidity) and in the humidity state about 30%.

15

Właściwa diagnostyka zawilgocenia budynku gwarantem trwałości hydrorewitalizacji

Ksit B., Tabiś K.

Materiały Budowlane

|

2018

|

nr 3

55--56

PL

W artykule przedstawiono algorytm postępowania oraz przykładowe urządzenia stosowane w celu określenia i rozwiązania problemu zawilgocenia przegród budowlanych przylegających do gruntu. Problemy z wilgocią dotyczą zarówno historycznych, jak i obecnie wznoszonych obiektów. Woda, która wnika kapilarnie w przegrody, powoduje nieodwracalne szkody w materiałach, które mogą doprowadzić do destrukcji budynku. Nieprawidłowa diagnostyka prowadzi do przyjęcia niewłaściwych metod hydrorenowacji, co powoduje dalszą degradację przegród. Algorytm postępowania przedstawiono na przykładzie diagnostyki prowadzonej na zawilgoconych obiektach.

EN

This article are presented algorithm of handling and example of devices used to determine and solve the problem of moisture in barrier walls in contact with ground. Problem with moisture concerns both historical buildings and recently built objects. Water that penetrates barrier walls by capillary action causes irreversible breakages on materials, that leads to destruction of the building. Improper diagnostics leads to adopting incorrect methods of hydro-renovation, what will cause further degradation of barrier walls. Algorithm of handling is presented by the case of diagnostics on damp objects.

16

Transport wilgoci w betonie komórkowym

Gębarowski P., Łaskawiec K.

Materiały Budowlane

|

2018

|

nr 4

112--113

17

Energy and environmental assessment of pellets produced from solid residues of the winery industry

Dolmaci E., Fokaides P. A., Polycarpoua P.

Journal of Power Technologies

|

2018

|

Vol. 98, nr 5

382--386

EN

The study assessed the potential of waste by-products from the Cypriot winery industry as raw material for solid biofuels. Two different biomass blends were pelletized and assessed as an energy source for domestic hot water boilers. The samples were composed of Grape Pomace (P1) and Grape Pomace & Vine Shoots Blends (P2) provided by a Cyprus winery: Aes Ambelis (Nicosia, 35°01’12.4"N 33°09’19.5"E). The raw material was dried and pelletized at the facilities of the Agricultural Research Institute (ARI), Cyprus. The pellets were analyzed for moisture and ash content using well-established standardized methods at the Sustainable Solid Fuels Lab of Frederick University, Cyprus. Combustion tests with the pellets were also carried out at the Boilers Lab of Frederick University. The measurement campaign focused on flue gas analysis – in particular carbon monoxide, carbon dioxide, oxygen, lambda – as well as water temperature and boiler efficiency. The results obtained from analysis of the samples showed that most of the examined pellets satisfied the minimum requirements of EN ISO 17225-2 and EN ISO 17225-6 standards for woody and non-woody pellets respectively. Ash content and moisture content for both samples also complied with the standards. The results of the measurement campaign were in good agreement with results delivered by other studies conducted for similar biomass raw material. Study results showed that grape pomace and grape pomace vine shoots blend could potentially be used as an energy source for producing heat which could be exploited for the domestic and industrial sectors. Harvesting this waste stream for energy production purposes could offer economically and environmentally smart solutions for the winery industry in Cyprus, satisfying the circular economy principles which are currently at the forefront of European environmental policy.

18

A non-destructive method of the evaluation of the moisture in saline brick walls using artificial neural networks

Goetzke-Pala A., Hoła A., Sadowski Ł.

Archives of Civil and Mechanical Engineering

|

2018

|

Vol. 18, no. 4

1729--1742

EN

The article presents a method of non-destructive evaluation of the moisture content in saline brick walls. This method is based on the use of artificial neural networks (ANNs) that are trained and tested on a database that was built for this purpose. The database was created based on laboratory tests of sample brick walls. The database contains over 1100 sets of results. Each set consists of two parameters that describe the dampness of the tested sample walls, which were determined using dielectric and microwave methods, and also three parameters that describe the concentration of salts in these walls. The ANN with back propagation error and the Broyden–Fletcher–Goldfarb–Shanno learning algorithm (BFGS) was used. It was shown that the proposed method of assessment allows reliable results to be obtained, which was confirmed by the high values of the linear correlation coefficient for learning, testing and experimental validation.

19

Metody pomiaru zawartości wilgoci w izolacyjnych szybach zespolonych

Rybicka-Łada J., Pabian S.

Świat Szkła

|

2017

|

R. 22, nr 4

23--25

20

Badania wilgotności murów ceglanych podziemia klasztoru księży Pallotynów oraz kościoła św. Wincentego w Biłohirii (Ukraina)

Nazarewicz B, Czeczin W.

Przegląd Budowlany

|

2017

|

R. 88, nr 9

76--79

PL

W referacie przedstawiono problemy związane z wykonawstwem oraz badaniami przyczyn zawilgocenia i stopnia zasolenia ścian (fundamentów) istniejących obiektów na przykładzie murów podziemia kościoła św. Wincentego w m. Biłohiria.

EN

The paper presents problems related to the execution and investigation causes of dampness and salinity of the walls (foundations) of existing objects on the example walls of the basement of Św. Vincent in Bihohiria.