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1

Fusion of differential analysis of volumetric strain method (dilatometric thermoporometry) and mercury intrusion porosimetry method for pore space characterization in carbonate rocks

Skowera Karol

Structure and Environment

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2023

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Vol. 15, no. 2

90--98

EN

Many characteristics of capillary-porous materials, including limestones and dolomites, depend on the structure of the pore space of a given material, so the article attempts to accurately determine the geometric characteristics of pores and their ability to transport water. Much information on the pore structure of carbonate rocks can be obtained from literature studies. There is a lack of information on the use of full hysteresis dilatometric thermoporometry methods for this purpose, as well as the fusion of differential analysis of volumetric strain (DAVS) results with mercury intrusion porosimetry (MIP) results. The subject of the research presented in this article is the analysis of pore structure in carbonate rocks using the method of differential analysis of volumetric strain and mercury intrusion porosimetry. Based on the measurements made, the pore size, pore volume, content of empty pores and pores containing water incapable of phase transformation were analyzed. The geometry of mesopores of rock samples examined by differential analysis of volumetric strain and mercury intrusion porosimetry was compared. A fusion of the distribution of mesopores from the DAVS study with a part of the distribution of meso- and macropores obtained by the MIP study was performer.

PL

Wiele cech materiałów kapilarno-porowatych, w tym wapieni i dolomitów, zależy od struktury przestrzeni porowej danego materiału, dlatego w artykule podjęto próbę dokładnego określenia cech geometrycznych porów i ich zdolności do transportu wody. Wiele informacji na temat struktury porów skał węglanowych można uzyskać ze studiów literaturowych. Brakuje informacji na temat wykorzystania w tym celu metod termoporometrii dylatometrycznej z pełną histerezą, a także połączenia wyników różnicowej analizy odkształceń (DAVS) z wynikami porozymetrii rtęciowej (MIP). Przedmiotem badań przedstawionych w niniejszym artykule jest analiza struktury porów w skałach węglanowych z wykorzystaniem metody różnicowej analizy odkształceń i porozymetrii rtęciowej. Na podstawie przeprowadzonych pomiarów przeanalizowano wielkość porów, objętość porów, zawartość porów pustych oraz porów zawierających wodę niezdolną do przemiany fazowej. Porównano geometrię mezoporów próbek skalnych badanych metodą różnicowej analizy odkształceń i porozymetrii rtęciowej. Wykonano fuzję rozkładu mezoporów z badania DAVS z częścią rozkładu mezo- i makroporów uzyskanych w badaniu MIP.

2

The impact of changes in pore structure on the compressive strength of sulphoaluminate cement concrete at high temperature

Tchekwagep J. J. K., Zhao P., Wang S., Huang S., Cheng X.

Materials Science Poland

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2021

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Vol. 39, No. 1

75--85

EN

The internal pore structure of sulphoaluminate cement concrete (SACC) significantly affects its mechanical properties. The main purpose of this study was to establish the relationship between pore structure changes and compressive strength after exposure to elevated temperatures. SACC samples that had been cured for 12 months were dried to a constant weight and then exposed to different temperatures (100 °C, 200 °C and 300 °C), after which the compressive strength and pore structure were measured. The pore structure of SACC was quantitatively described by mercury intrusion porosimetry (MIP) and nitrogen adsorption results. The results showed that with increased temperature, the porosity of the SACC samples also increased and the pore structure was gradually destroyed. Moreover, the SACC’s compressive strength gradually decreased with increasing temperature. The relationship between compressive strength and porosity was in close agreement with the compressive strength–porosity equation proposed by Schiller. Therefore, after extensive exposure to elevated temperature, the changes in SACC’s compressive strength can be quantitatively described by the Schiller equation.

3

Effect of the ground granulated blast furnaceslag on the pore structure of concrete

Chalid Abdul

Archives of Civil Engineering

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2021

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Vol. 67, nr 1

203--214

EN

The objective of this study is to analyze effect of ground granulated blast furnace slag (GGBFS) in concrete on the pore structure, this research will contribute to the knowledge regarding the use of GGBFS as a cementitious material in terms of the future reference and potential improvement to the properties of concrete. To this aim, on the one hand a control specimens (CS) and another samples with 40% and 60% of GGBFS as replacement cement with moist cured at 20°C, 27°C, and cured at site. The compressive strength and the Mercury intrusion porosimetry (MIP) test were done. The result indicates that the strength of concrete with GGBFS at early ages tend to be lower in comparison with the CS. However, the GGBFS reaction plays important roles at the later ages. The samples cured at higher temperature produce higher strength value. The total pore volume (TPV) of the concrete use GGBFS decreases with increasing age.

4

Cement paste microporosity analysis: a comparison of different experimental techniques

Bednarska Dalia, Koniorczyk Marcin

Technical Transactions

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2019

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Vol. 116, iss. 9

71--80

EN

Microstructure defines almost all material physical properties of a substance. Thus, its proper identification is essential for the assessment of material durability. Porous materials constitute the vast majority of those applied in civil engineering. The most important parameters describing a porous structure are the specific surface area, the shape and volume of pores and the pore size distribution. There are several methods which provide such results; however, each of them has some drawbacks. The main purpose of this paper is to compare results obtained by means of various methods commonly applied to the investigation of microstructure. These methods are mercury intrusion porosimetry (MIP), low temperature sorption of nitrogen and thermoporometry (TPM). The experimental research is conducted on aluminium oxide, which is characterised by unimodal pore size distribution and hardened cement paste prepared using portland cement (CEM I 42.5R with water-cement ratio equal to 0.5. The results obtained by the above-mentioned methods are thoroughly described and compared in this paper. Each of the presented approaches has some limitations; therefore, in order to receive a reliable description of porous microstructure, one has to apply at least two different experimental methods.

PL

Wśród materiałów budowlanych przeważającą większość stanowią materiały porowate. Dokładna znajomość mikrostruktury jest kluczowa w ocenie ich wytrzymałości i trwałości. Istnieje wiele metod eksperymentalnych służących do analizy struktur porowatych. W niniejszym opracowaniu porównane zostały następujące techniki: porozymetria rtęciowa (MIP), niskotemperaturowa adsorpcja azotu oraz termoporometria (TPM). Badaniom eksperymentalnym poddano dwa materiały. Pierwszy z nich, tlenek glinu, jest materiałem referencyjnym o unimodalnym rozkładzie porów. Zgodnie z deklaracją producenta dominująca średnica porów wynosi 7.3 nm. Drugim zastosowanym materiałem jest zaczyn cementowy przygotowany na bazie cementu portlandzkiego CEM I 42,5R. Stwardniały zaczyn charakteryzuje się skomplikowanym rozkładem porów. Opisane techniki analizy mikrostruktury są komplementarne. Aby uzyskać wiarygodny opis struktury wewnętrznej materiałów o skomplikowanym rozkładzie porów należy zastosować co najmniej dwie metody badawcze.

5

Współczesne metody badania materiałów budowlanych pochodzących z zabytkowych obiektów murowanych

Stryszewska Teresa, Kańka Stanisław

Materiały Budowlane

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2019

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nr 3

39--41

PL

W artykule przedstawiono przykłady zaawansowanych badań mineralnych materiałów budowlanych pobranych z murowanych obiektów zabytkowych o wartości historycznej. W celu identyfikacji materiałów, ich składu fazowego oraz określenia specyficznych właściwości, w tym stopnia skażenia solami, wykonano badania petrograficzne, obserwacje w mikroskopie skaningowym wraz z analizą dyspersji energii promieniowania rentgenowskiego pierwiastków, a także określono strukturę porowatości. Badania umożliwiające ocenę materiału na podstawie bardzo małych próbek mają ogromne znaczenie w przypadku obiektów zabytkowych, w tym o charakterze martyrologicznym, gdyż obowiązuje wówczas wiele ograniczeń wynikających z konieczności zachowania substancji oryginalnej i zminimalizowania ingerencji związanej z pobieraniem próbek.

EN

The paper present examples of advanced studies of mineral building materials collected from facilities located within the area of the former Auschwitz-Birkenau camp. These facilities are characterised by great historical value. In order to identify the materials and their phase composition, and to determine their specific properties, including the extent of salt contamination, petrographic examinations were performed as well as SEM observations along with an energy dispersive X ray analysis and porosity structure. It has been stressed in the paper that testing methods that enable evaluation of the material based on very small samples is of great importance in the aspect of heritage facilities including those associated with suffering where many restrictions are applicable due to the requirement that the original substance should be retained and the interference in connection with the sampling should be minimised.

6

Particle size characterisation of SCMs by mercury intrusion porosimetry

Klemm A. J., Wiggins D. E.

Fizyka Budowli w Teorii i Praktyce

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2017

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T. 9, nr 1

5--12

EN

Mercury intrusion porosimetry (MIP) is widely used for the microstructural characterisation of porous solids. Comparatively few studies have employed the technique to characterise the size of particles within powdered samples. The present study uses the MIP technique to characterise the particle sizes of contemporary supplementary cementitious materials (SCMs), and in particular uses the technique to present particle size distributions, rather than a single mean size. Representivity of the technique for known limitations of non-spherical and porous particles are checked using the Scanning Electron Microscope. The findings indicate that the MIP affords a good approximation of particle sizes, including distributions, of spherical and non-spherical particles. The technique was also found to provide reasonable accuracy for estimating the particle sizes of highly porous particles, where distinction between inter-particle and intra-particle porosity was made.