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1

Nanoindentation: a comprehensive review with a proposed standardized workflow

Băncilă Ioana-Cristina

Advances in Mechanical and Materials Engineering

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2026

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Vol. 43, nr 1

79--94

EN

Nanoindentation is a method for mapping the mechanical properties of heterogeneous materials. This paper aims to provide a review of this method, the challenges that still remain in spite of recent innovations and future recommendations. Various types of indenters and sample preparation methods, together with displacement-load curves ensure the correctness of operation process and correct manipulation of nanoindentation device. The novelty of this work lies in the proposed workflow in schematic way, that integrates Atomic Force Microscopy (AFM), Density Functional Theory (DFT) and Finite Element Method (FEM) into a single sequence. This approach enables the cross-validation between computational, experimental and quantum mechanical methods, providing a comprehensive characterization of material from macroscale to nanoscale. This workflow serves also as a standardized guideline, that may help to enhance reproducibility and interpretability for bone mechanical properties, thus it can be used for interdisciplinary projects and become a routine tool in material science and biomedical applications.

PL

Nanoindentacja to metoda mapowania właściwości mechanicznych materiałów niejednorodnych. Niniejszy artykuł ma na celu dokonanie przeglądu tej metody oraz wyzwań, które wciąż istnieją pomimo innowacji wprowadzanych w tym obszarze. Różnorodne rodzaje wgłębników i metody przygotowywania próbek, wraz z krzywymi przemieszczenie-obciążenie, zapewniają poprawność procesu pomiarowego i prawidłowe wykorzystanie urządzeń do nanoindentacji. Nowość niniejszej pracy polega na zaproponowaniu procedury postępowania, która integruje mikroskopię sił atomowych, teorię funkcjonału gęstości i metodę elementów skończonych. Takie podejście umożliwia walidację krzyżową metod obliczeniowych, eksperymentalnych i mechaniki kwantowej, zapewniając kompleksową charakterystykę materiału od makro-do nanoskali. Zaproponowana procedura postępowania stanowi znormalizowane wytyczne, które mogą pomóc w zwiększeniu powtarzalności i interpretowalności właściwości mechanicznych kości, dzięki temu może być wykorzystywana w projektach interdyscyplinarnych i stać się rutynowym narzędziem w materiałoznawstwie i zastosowaniach biomedycznych.

2

Wpływ stosowania cementu wieloskładnikowego CEM II/C-M (V-LL) na podstawowe parametry wytrzymałościowe betonu

Walczak Aleksandra

Przegląd Budowlany

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2025

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R. 96, nr 5

90--93

PL

W niniejszym artykule zbadano wpływ stosowania cementu wieloskładnikowego CEM II/C-M (V-LL) w matrycy cementowej betonu na jego podstawowe parametry wytrzymałościowe. W myśl Europejskiego Zielonego Ładu i strategii opartej na zmniejszeniu ilości emisji dwutlenku węgla wprowadzono do mieszanki betonowej cement o zmniejszonej ilości klinkieru portlandzkiego w swoim składzie (CEM II) względem obecnie stosowanych w powszechnym budownictwie cementów (CEM I). Badaniu poddano podstawowe parametry wytrzymałościowe betonu: wytrzymałość na ściskanie, wytrzymałość na rozciąganie, moduł sprężystości. Sporządzono krzywą uziarnienia oraz krzywą przyrostu wytrzymałości na ściskanie betonu w czasie. Zbadane parametry uznano za strategiczne i mające znaczący wpływ na znajdujące praktyczne zastosowanie aspekty wymiarowania konstrukcji żelbetowych jak m.in. długość zakładu i zakotwienia prętów zbrojeniowych, ugięcie belek oraz nośność elementów.

EN

This article investigates the effect of using CEM II/C-M (V-LL) multi-component cement in the cement matrix of concrete on its basic strength parameters. In accordance with the European Green Deal and a strategy based on reducing carbon dioxide emissions, a cement with a reduced amount of Portland clinker in its composition (CEM II) was introduced into the concrete mix relative to the cements currently used in common construction (CEM I). The basic strength parameters of concrete were tested: compressive strength, tensile strength, modulus of elasticity. The grain size curve and the curve of increase in compressive strength of concrete over time were prepared. The studied parameters were considered strategic and have a significant impact on the practically applicable aspects of the dimensioning of reinforced concrete structures such as the length of the overlap and anchorage of reinforcing bars, the deflection of beams and the load carrying capacity of elements.

3

Dynamiczne właściwości fibrobetonu wytworzonego na bazie piasków odpadowych

Kobaka Janusz, Katzer Jacek, Zawidzki Machi

Pomiary Automatyka Robotyka

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2025

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R. 29, nr 1

75--79

PL

W artykule przedstawiono wyniki badań nieniszczących fibrobetonu z dodatkiem włókien stalowych wytworzonego na bazie piasków odpadowych. Belki fibrobetonowe o różnej zawartości włókien stalowych poddane były dwóm rodzajom drgań własnych: drganiom skrętnym i giętnym. Na podstawie przeprowadzonych testów i analizy Fouriera, wyznaczono częstotliwości tych drgań. Posłużyły one do określania dynamicznego modułu sprężystości, dynamicznego modułu odkształcenia postaciowego oraz dynamicznego współczynnika Poissona. Następnie określono wpływ włókien stalowych na te parametry. Badania wykazały, że dodatek włókien stalowych wpływa na zwiększenie dynamicznego modułu sprężystości oraz dynamicznego modułu odkształcenia postaciowego do pewnej krytycznej zawartości włókien, po przekroczeniu której, następuje zmniejszenie wartości tych modułów, ponadto włókna stalowe nie wpływają na wartości dynamicznego współczynnika Poissona.

EN

The article presents the results of non-destructive testing of steel fiber reinforced concrete (SFRC) based on waste sand. Fiber concrete beams with different steel fiber content were subjected to two types of free vibrations: torsional and flexural vibrations. Based on the tests and Fourier analysis, the frequencies of these vibrations were determined. They were used to determine the dynamic modulus of elasticity (Young’s modulus), the dynamic shear modulus (modulus of rigidity) and the dynamic Poisson’s ratio. In the next stage, the influence of steel fibers on these parameters was determined. The tests have shown that the addition of steel fibers increases the value of dynamic modulus of elasticity and the dynamic shear modulus up to a certain critical fiber content, beyond which the values of these moduli decrease; moreover, steel fibers do not affect the value of the dynamic Poisson’s ratio.

4

Studies on the behaviour of EPS polystyrene under compression in the light of standard provisions and subject literature

Słowiński Kamil

Materiały Budowlane

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2025

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nr 4

63--69

EN

The article discusses selected provisions of the PN-EN ISO 29469:2023-05 standard regarding the testing methodology and the method of assessing the results of the EPS polystyrene compression test, in the context of the preparation of test elements, the testing procedure and assessment of the results of the EPS polystyrene compression test and the possible possibility of structural use of this material. The provisions of the standard are discussed against the background of research results presented in the literature on the subject and the author's own research. The need to supplement the standard provisions is indicated.

PL

W artykule omówiono wybrane zapisy normy PN-EN ISO 29469:2023-05 dotyczące metody badań i sposobu oceny wyników próby ściskania polistyrenu EPS, w kontekście przygotowania elementów próbnych, procedury badań i oceny wyników próby ściskania polistyrenu EPS oraz ewentualnej możliwości konstrukcyjnego wykorzystania tego materiału. Zapisy normy omówiono na tle rezultatów badań przedstawionych w literaturze przedmiotu oraz badań własnych. Wskazano przy tym na konieczność uzupełnienia zapisów normowych.

5

Reakcja gruntów antropogenicznych na obciążenia cykliczne

Głuchowski Andrzej, Sas Wojciech, Zając Kamil, Rzepczyńska Luiza

Inżynieria i Budownictwo

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2025

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R. 81, nr 5

564--568

PL

W artykule przedstawiono analizę reakcji gruntów antropogenicznych na obciążenia cykliczne, ze szczególnym uwzględnieniem dwóch głównych grup: odpadów budowlano-rozbiórkowych (ang. Construction & Demolition Wastes, C&D) oraz przemysłowych odpadów stałych (ang. Industrial Solid Wastes, ISW). Grunty te, powstające jako uboczny produkt działalności człowieka, coraz częściej znajdują zastosowanie w geotechnice jako substytuty lub materiały alternatywne dla gruntów naturalnych, szczególnie w kontekście zrównoważonego budownictwa i rekultywacji terenów zdegradowanych. Przedstawiona w artykule analiza wykazała, że grunty antropogeniczne mogą wykazywać istotnie odmienne właściwości w porównaniu z gruntami naturalnymi obciążonymi cyklicznie, w tym zwiększoną podatność na akumulację odkształceń trwałych i zmniejszenie sztywności. W artykule podkreślono konieczność indywidualnej oceny przydatności gruntów antropogenicznych w warunkach obciążeń cyklicznych oraz potrzebę standaryzacji badań identyfikujących ich parametry cykliczne.

EN

The article presents an analysis of the response of anthropogenic soils to cyclic loading, with particular emphasis on two main groups: Construction & Demolition Wastes (C&D) and Industrial Solid Wastes (ISW). These soils, which originate as by-products of human activity, are increasingly being used in geotechnical engineering as substitutes or alternative materials to natural soils, especially in the context of sustainable construction and the reclamation of degraded areas. The analysis presented in the article has shown that anthropogenic soils may exhibit significantly different properties compared to natural soils under cyclic loading, including increased susceptibility to the accumulation of permanent deformations and a reduction in stiffness. The article emphasizes the necessity of an individual assessment of the suitability of anthropogenic soils under cyclic loading conditions, as well as the need to standardize testing procedures for identifying their cyclic parameters.

6

Badania doświadczalne betonu stosowanego w prefabrykacji, zbrojonego włóknami polimerowymi

Głuszko Agnieszka

Inżynieria i Budownictwo

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2025

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R. 81, nr 6

660--665

PL

Celem pracy była ocena wpływu zbrojenia rozproszonego z włókien syntetycznych na właściwości mechaniczne betonu stosowanego w prefabrykacji. Badania wykonano na betonach klasy C45/55 z dodatkiem mikro- i makrowłókien polipropylenowych w ilości od 3,0 do 4,0 kg/m3. Sprawdzono wytrzymałość na ściskanie, moduł sprężystości, wytrzymałość na rozciąganie przy zginaniu oraz wytrzymałość resztkową według procedur europejskich norm. Stwierdzono, że dodatek włókien nie wpływa istotnie na wytrzymałość na ściskanie, lecz powoduje zwiększenie wytrzymałości resztkowej, szczególnie w przypadku mieszanek zawierających makrowłókna MP40. Wyniki wskazują, że wzrost smukłości włókien przekłada się bezpośrednio na zwiększenie modułu sprężystości kompozytu. Przeprowadzone badania potwierdzają możliwość zastosowania fibrobetonu jako alternatywy dla tradycyjnego betonu w prefabrykowanych elementach konstrukcyjnych.

EN

The aim of the study was to assess the effect of dispersed reinforcement with synthetic fibres on the mechanical properties of concrete used in prefabrication. The tests were carried out on C45/55-grade concretes with the addition of micro- and macro-polypropylene fibres in amounts ranging from 3.0 to 4.0 kg/m3. The compressive strength, modulus of elasticity, flexural tensile strength, and residual strength were determined in accordance with European standard procedures. It was found that the addition of fibres does not significantly affect compressive strength but enables obtaining favourable residual strength values, particularly in mixtures containing MP40 macro-fibres. The results indicate that an increase in fibre slenderness directly translates into a higher modulus of elasticity of the composite. The obtained findings confirm the possibility of using fibre-reinforced concrete as an alternative to conventional concrete in prefabricated structural elements.

7

Influence of curing time on the effectiveness of polypropylene fibers in cement-stabilized soil improvement

Miturski Maciej

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

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2025

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Nr 3

57--66

EN

Soil stabilization is a commonly used method of improving subgrade properties in road construction. Despite many years of using this technology, intensive research continues to be conducted to enhance the effectiveness of stabilization processes. One approach used to improve the unconfined compressive strength (UCS) of stabilized soils is the incorporation of dispersed reinforcement. This study focuses on investigating the effect of polypropylene fibers on the effectiveness of cement-stabilized soil improvement as a function of time. For the study, samples were prepared based on two mixtures containing 4% cement. The first did not include any fibers, while the second contained 0.5% fibers. Six series of samples were prepared for each mixture, which were then subjected to uniaxial compression tests after 1, 3, 7, 14, 28, and 56 days of the curing process. Based on the collected data, an analysis was performed to examine the change in Effectiveness of Fiber Improvement (EFI) over time. The study of the test results showed that in the initial phase of curing, the effectiveness of fiber enhancement reached 165.9%, then gradually decreased over time to about 119.9%. Furthermore, the study also presented the significant impact of fibers on the E50 deformation modulus value, as well as the relationship between this parameter and the unconfined compressive strength of stabilized soil. Based on the results obtained, the mechanisms of soil improvement and their impact on the change in effectiveness over time were described. The presented results and conclusions facilitate a deeper understanding of the improvement of soil stabilized with polypropylene fibers.

8

A new approach to determining the elastic modulus of structural materials

Zhigun Valery, Chatys Rafał, Plume Egils

Composites Theory and Practice

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2025

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R. 25, nr 3

217--225

EN

Stiffness characteristics are often decisive in the choice of material for structural parts. At the same time, the process of their determination for anisotropic materials does not fully satisfy the requirements in terms of reliability and reproducibility. This work is devoted to the development of an approach for determining the moduli of elasticity. An analysis of the Timoshenko approaches developed to estimate the shear component of deflection in transverse bending is presented. The drawbacks preventing their use as a basis for modern methods of determining the elastic components of structural materials are noted. An approach for determining the elastic moduli is proposed, the basis of which are the maximum values of deflections and angles of rotation of the cross-sections of a specimen under three-point transverse bending. The relationship between angular and linear displacements under the considered type of loading is established, which allows stable and reliable values of elasticity moduli to be obtained from the data of angular displacements. The acceptability of the proposed approach for determining the elastic moduli of both isotropic materials and composites is shown.

9

Experimental study on triaxial compression mechanical properties of grouting reinforcement of broken surrounding rock

Yang Peng, Pang Dongdong

Archives of Mining Sciences

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2025

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Vol. 70, no. 2

273--291

EN

Grouting is a widely used method of reinforcement for stabilising fractured surrounding rock. To investigate the triaxial compression behaviour of surrounding rock after grouting reinforcement, laboratory-prepared grouted specimens were subjected to triaxial compression tests using an RMT-150B testing system. The analysis focused on the effects of confining stress, particle size, and water-to-cement ratio on the stress-strain behaviour. The internal friction angle and cohesion were determined based on the Mohr-Coulomb criterion. The variations in strain at peak stress and the elastic modulus were clarified, and the failure modes of the grouted specimens were examined. Additionally, Kendall’s correlation analysis was employed to evaluate the relationship between confining stress and other parameters. The results indicate that increasing confining stress significantly enhances the load-bearing capacity of the surrounding rock. The optimal rock particle gradation was observed when the particle size ranged between 5-10 mm, yielding the highest compressive capacity. Conversely, increasing the water-to-cement ratio reduced the strength of the specimens. Among the analysed factors, confining stress exhibited the strongest correlation with peak stress.

10

The influence of spark plasma sintering parameters on the microstructure, physical, and mechanical properties of ZrO2–3 mol% Y2O3 ceramics

Kulyk V.V., Duriagina Z.A., Vasyliv B.D., Lyutyy P.Y., Klimczyk P., Vavrukh V.I., Kostryzhev A.

Archives of Materials Science and Engineering

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2025

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Vol. 132, nr 2

73--85

EN

Purpose: The purpose of the work is to study the effect of the SPS sintering temperature on the transformation of the phase composition, microstructure, and the set of physical and mechanical properties of ZrO2–3 mol% Y2O3 ceramics. Design/methodology/approach: Yttria-stabilised zirconia ceramic samples of the ZrO2–3 mol% Y2O3 composition (3YSZ) were fabricated from corresponding powder by spark plasma sintering (SPS) at temperatures of 1150–1350°C under a constant pressure of 63 MPa with a holding time of 4 min. The sample density and porosity were estimated by Archimedes’ method. The elastic moduli of the ceramics were determined using a Panametrics EPOCH III ultrasonic tester. Microhardness of the ceramics was determined by the Vickers indentation method using a NOVOTEST TC-MKB1 microhardness tester. The fracture toughness of the ceramics was estimated by the single-edge notched beam (SENB) and the Vickers indentation test methods. A UIT STM 050 test machine with a self-made three-point bending test unit was used for the determination of the SENB fracture toughness and flexural strength of the ceramics. All mechanical tests were performed in air at 20°C. A Malvern Panalytical X-ray diffractometer (XRD) was used for XRD analysis. Scanning electron microscopes, Hitachi SU3900 and Thermo Scientific Apreo 2C, Findings: It is shown that 3YSZ ceramics sintered at 1200°C have the optimal phase composition and morphology of the individual microstructure components, which provides the highest crack growth resistance. Due to the differences in the microstructure of ceramics manufactured by the high-speed spark plasma sintering method, it is recommended to use traditional methods of fracture mechanics, along with the indentation method, to determine their fracture toughness accurately. Research limitations/implications: The operating atmosphere, temperature, and pressure are the crucial parameters for the ceramic products. It requires estimating the microhardness, flexural strength, and fracture toughness of the ceramics under such conditions. Practical implications: The research results enable the design of the microstructure of 3YSZ ceramics through SPS sintering, providing high reliability of ceramic products across various industrial branches by achieving the necessary physical and mechanical properties. Originality/value: The balance of tetragonal and monoclinic zirconia phases and microstructure of the 3YSZ ceramics sintered by SPS at various temperatures were evaluated and linked to the mechanical behaviour of the ceramics; the SENB and Vickers indentation methods were applied to estimate crack growth resistance of 3YSZ ceramics, and a high-energy consuming fracture micromechanism corresponding to the appropriate sintering mode was found.

11

Evaluation of mechanical performance in polymer composites reinforced with particles and fibers

Ali Aenas Laith, Habeeb Diyar

Archives of Engineering Knowledge

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2025

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T. 11, Nr 1

13--19

EN

In this study, polymer-based hybrid composites were fabricated using the hand-casting technique, with unsaturated polyester resin serving as the core material. The composites were reinforced with a fixed volume fraction (15%) of glass fiber mat (GLASS-E). Two sets of samples were prepared: the first set was reinforced with graphite particles, while the second set used Kevlar mat fibers (50) as reinforcement instead of glass fibers. The effects of varying volume fractions (2%, 8%, 14%, 20%, and 26%) of graphite particles, with particle sizes ranging from 100 μm to 20 μm, on the mechanical properties of the composites were thoroughly investigated. Comprehensive mechanical tests including tensile, compression, impact, flexural, shear, and hardness tests - were conducted at room temperature to evaluate the material’s performance. The results revealed that increasing the volume fraction of graphite particles led to enhancements in tensile strength, compressive strength, tensile modulus, fracture toughness, and overall hardness. Additionally, flexural stiffness and shear stress values improved as the graphite content increased. Conversely, the compressive modulus showed an increase at lower graphite volume fractions but decreased at higher fractions in both groups. The impact resistance tests indicated that the hybrid composites reinforced with graphite particles and Kevlar fibers exhibited higher values of tensile strength, tensile modulus, compressive modulus, impact strength, and fracture toughness than those reinforced with glass fibers. However, the composites with glass fibers demonstrated superior compressive strength, stiffness, flexural strength, and shear stress compared to the Kevlar-reinforced composites.

12

Study on cracking resistance of polyvinyl alcohol fiber-reinforced low-dose cement-stabilized crushed stone

Yan Xin, Zhou Zhigang, Jin Jian

Archives of Civil Engineering

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2025

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Vol. 71, nr 1

141--155

EN

In this paper, the effects of polyvinyl alcohol fiber incorporation on the crack resistance of low-dose cement-stabilized crushed stone have been investigated. The resulting change in the compressive strength, compressive rebound modulus, splitting strength, dry shrinkage factor, and impact toughness with fiber incorporation was evaluated through the unconfined compressive strength test, compressive rebound modulus test, crack strength test, dry shrinkage test, and impact toughness test. The results showed the positive influence of PVA fibers on the crack resistance of low-dose cement-stabilized crushed stone. PVA fibers have been shown to improve the compressive strength, splitting strength, and impact toughness of low-dose cement-stabilized crushed stone while reducing the compressive rebound modulus and dry shrinkage factor. With the increase of fiber incorporation, the compressive strength, splitting strength, and impact toughness tend to increase first and then decrease. The compressive resilience modulus and dry shrinkage coefficient showed a tendency to decrease first and then increase. When the fiber dosage is 0.9 kg/m3, the maximum energy consumed in the fracture of the specimen, the strongest impact resistance and impact ductility of the material, the indexes reach the optimal value, indicating that the crack resistance of PVA fiber low-dose cement-stabilized crushed stone is optimal at this dosage. This study provides a theoretical basis for promoting and applying PVA fiber in low-dose cement-stabilized gravel.

13

Investigation on the dynamics of movement of cylindrical cleaning pigs through the bends of pipeline systems for fluid transportation

Stetsiuk Serhii, Doroshenko Yaroslav, Bondarenko Robert, Fіlipchuk Oleksandr, Volovetskyi Volodymyr

Zeszyty Naukowe. Transport / Politechnika Śląska

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2024

|

z. 123

303--317

EN

Development and implementation of methods for cleaning the internal cavity of pipelines in the process of transporting fluids is important to ensure their energy efficiency and safe operation. The dynamics of the movement of one-piece cylindrical cleaning pistons made of various materials (silicone compound, self-destructive elastic polymer composition, polyurethane foam assembly foam) in the pipelines of pipeline systems intended for fluid transportation were studied by modelling and experimentally. The dynamics of movement of solid cylindrical cleaning pigs made from various materials (silicone compound, self-destructive elastic-polymer composition, polyurethane foam) in bends of pipeline systems intended for fluid transportation were studied through modelling and experiments. The analysis of forces acting on the pig during its movement in the pipeline bend was conducted, and the equations of pig motion based on Newton's second law were formulated. Contact forces of normal reaction, arising due to pig bending in the pipeline bend and determining the magnitude of frictional force between the pig and the inner wall of the bend, were determined based on classical bending theory. The impact of the material's modulus of elasticity, from which the pig is made, on the magnitude of contact forces of normal reaction at the pig pressing points against the inner wall of the pipeline bend was established. A method for determining the conditions under which pigs made from different materials will pass through pipeline bends without stopping and getting stuck was proposed. An equation for calculating the minimum allowable pig movement speed at the entrance to the bend to ensure its passage without stopping and getting stuck was derived.

14

The influence of chloride ions content on the mechanical properties of concrete

Szweda Zofia

Structure and Environment

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2024

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Vol. 16, no. 3

158--165

EN

This paper presents an analysis of the effect of concrete salinity on the splitting tensile strength of specimens taken directly from the HC-500 floor slab and the flexural and compressive strength and the value of the modulus of elasticity of specimens made under laboratory conditions from lightweight concrete and ordinary concrete. The tests were carried out in two variants: in the first, chloride ions were introduced into the concrete by the migration method and in the second, as an additive introduced directly with the batch water. The analysis showed that the additive can affect certain mechanical properties of concrete both favorably and unfavorably. The results indicate that it is important to examine the issue of the influence of salinity on concrete’s mechanical properties. This knowledge can be applied to the modeling of damage in reinforced concrete structures resulting from exposure to chloride-rich environments.

PL

W niniejszej pracy przedstawiono analizę badań wpływu zasolenia betonu na wytrzymałość na rozciąganie przy rozłupywaniu próbek pobranych bezpośrednio z płyty stropowej HC-500 oraz wpływu zasolenia na wytrzymałość na zginanie i ściskanie oraz na wartość modułu sprężystości próbek wykonanych w warunkach laboratoryjnych z betonu lekkiego i betonu zwykłego. Badania przeprowadzono w dwóch wariantach: w pierwszym po wprowadzeniu jonów chlorkowych do betonu metodą migracyjną w próbkach pobranych z płyt HC-500 i wykonanych z betonu lekkiego i w drugim, jako dodatek wprowadzony bezpośrednio z wodą zarobową w próbkach z betonu zwykłego. Przeprowadzone badania porównawcze różnych betonów z dodatkiem NaCl wykazały, że dodatek ten może wpływać zarówno korzystnie, jak i niekorzystnie na niektóre właściwości mechaniczne betonu. Przeprowadzone badania wskazują, że istotne jest dokładniejsze rozpoznanie zagadnienia wpływu zasolenia betonu na jego właściwości mechaniczne, co może być następnie wykorzystane w procesie modelowania zniszczeń konstrukcji żelbetowych wywołanych oddziaływaniem środowiska zawierającego chlorki.

15

Elektrownia Szczytowo-Pompowa Porąbka-Żar : badania geofizyczne dla oceny warunków posadowienia oraz pomiary geodezyjne w eksploatacyjnej ocenie stanu technicznego

Bestyński Zbigniew, Pacanowski Grzegorz, Ryfa Tomasz, Wziątek Dagmara Zelaya

Przegląd Geologiczny

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2024

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Vol. 72, nr 12-2

772--780

EN

The article presents an outline of the Pumped Storage Power Plant (PSPP) Porąbka-Żar construction and the geological structure of the area of its location as well as the results of comprehensive geophysical, seismic and geoelectric research used to identify the conditions of its foundation. Different methodologies, techniques of geophysical research as well as the measurement equipment used 55 years ago were presented. The methodology and technique as well as the results of currently performed periodic control tests of the deformation of the main basin and the embankments of the upper reservoir, performed using the laser scanning method to assess its technical condition, were also presented.

16

Improving mechanical and thermal properties of unsaturated polyester resin by adding automotive glass waste

Hemadi Assis Ekhlass K., Al-Ahmady Kossay K., Sulyman Ebtahag Z.

Ochrona przed Korozją

|

2024

|

nr 10

294--305

EN

The primary goal of this study was to improve a number of mechanical properties of UPE (unsaturated polyester) by using available and cheap particulate fillers, such as reinforcement with powder with a particle size of 75 μm. A composite of UPE with automotive glass waste (as filler materials) was prepared, and some mechanical and thermal properties were studied at certain weight percentages (5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, and 50%). A comparison was made between the polymeric composites before and after the process of reinforcing them with waste automotive glass, and it was found that with a 30% content of these additives they showed good mechanical properties. These additions were made at different temperatures: 8°C, 25°C and 50°C. The results before and after the reinforcement process for polymer composites showed that there was an improvement in the mechanical properties (compressive strength, hardness and impact resistance) with a decrease in the modulus of elasticity (Young’s modulus). When processing was carried out at a temperature of 8°C, a decrease in the values of the mechanical properties (compressive strength, impact strength, modulus of elasticity, thermal conductivity) was observed in varying proportions, with an increase in the values of hardness. Conversely, when the samples were heated to a temperature of 50°C, there was an increase in the values of the above-mentioned properties and a significant decrease in the hardness values. Throughout the research, various measurement techniques were used, including scanning electron microscopy (SEM), infrared spectroscopy (IR) and thermogravimetric analysis (TGA). Their purpose was to monitor the changes that occurred in the polymer as a result of the use of the reinforcing material (automotive glass).

PL

Głównym celem badań było poprawienie właściwości mechanicznych UPE (nienasyconego poliestru) poprzez zastosowanie dostępnych i tanich wypełniaczy cząsteczkowych, na przykład przez wzmocnienie proszkiem o wielkości cząstek wynoszącej 75 μm. Przygotowano kompozyt UPE ze szklanymi odpadami przemysłu motoryzacyjnego (jako materiałem wypełniającym) i zbadano wybrane właściwości mechaniczne i termiczne przy określonych procentach wagowych (5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45% i 50%). Porównano kompozyty polimerowe przed procesem wzmacniania odpadami szklanymi i po nim. Stwierdzono, że przy 30-procentowym udziale tych dodatków wykazywały one dobre właściwości mechaniczne. Dodatki zostały wprowadzone w różnych temperaturach: 8°C, 25°C i 50°C. Analiza wyników przed wzmocnieniem kompozytów polimerowych i po tym procesie wykazała, że nastąpiła poprawa właściwości mechanicznych (wytrzymałości na ściskanie, twardości i udarności) przy spadku modułu sprężystości (modułu Younga). Po przetwarzaniu w temperaturze 8°C odnotowano spadek wartości parametrów mechanicznych (wytrzymałości na ściskanie, udarności, modułu sprężystości, przewodności cieplnej) w różnych proporcjach przy jednoczesnym wzroście twardości. Z kolei po podgrzaniu próbek do temperatury 50°C zwiększyły się wartości wymienionych właściwości i znacznie zmniejszyła twardość. W badaniach wykorzystano różne techniki pomiarowe, w tym skaningową mikroskopię elektronową (SEM), spektroskopię w podczerwieni (IR) i analizę termograwimetryczną (TGA), w celu zweryfikowania zmian zachodzących w polimerze w wyniku zastosowania materiału wzmacniającego (szklanych odpadów przemysłu motoryzacyjnego).

17

Study of the Behaviour of Moment-Resisting Connection of Softwood Timber Elements

Fabriciuss Janis, Ozola Lilita

Inżynieria Mineralna

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2024

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Vol. 1, no. 2

art. no. 25

EN

Timber moment-resisting connections present opportunities for streamlined architectural design using timber portal frames with rigid knee junctions, enabling open floor plans by eliminating the need for additional bracing or interior columns. This flexibility empowers architects to craft more versatile floor layouts, enhancing spatial aesthetics and functionality. However, moment-resisting connections between timber members, especially crossing ones, present several challenges – complex design, demanding meticulous detailing and precise fabrication and also lack of a detail design format in codes. One of the biggest disadvantages of timber moment-resisting connections made by steel dowels is development of relative rotation due to the timber as well as dowel’s elastic-plastic behaviour, i.e., such connection may be referred to a semi-rigid group. The main objective of this study is to conduct a detailed investigation of semi-rigid timber connections by performing experimental tests of L-shape models, including examination of timber strength and stiffness properties. The rotational displacement between joined members was determined using measured distances between surface points by Particle Image Velocimetry (PIV). The experimental results are compared with an equivalent linear calculation model. Different connection models are treated by Dlubal RFEM software tools using experimentally obtained embedment stiffness variables. It is found that the linear behavior of the semi-rigid connection is up to approximately 40% of the connection's design capacity, after which distinctly nonlinear force-deformation relationship develops.

18

Mechanical properties of glass fiber-reinforced backfills under different proportion conditions

Zhao Kang, Yang Jian, Zhong Juncheng, Yan Yajing, Tian Xiangqin, Feng Yincheng

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 3

art. no. e196, 2024

EN

To investigate the mechanical properties of glass fiber-reinforced backfills under different proportion conditions, uniaxial compression tests were conducted on glass fiber-reinforced backfills with different slurry concentrations (65%, 68%, and 72%) and different cement–tailings ratios (1:6, 1:8, and 1:10). The effects of slurry concentration and cement–tailings ratio on the mechanical performance parameters, failure modes, and energy evolution of the glass fiber-reinforced backfills were discussed, and the effect mechanism of glass fiber on the overall mechanical properties of the backfills was revealed from a microscopic perspective. The results show that the slurry concentration and cement–tailings ratio have significant effects on the elastic modulus and uniaxial compressive strength of the glass fiber-reinforced backfill. The strength of the backfill reaches a maximum value of 2.831 MPa at a slurry concentration of 72% and a cement–tailings ratio of 1:6. The damage of the glass fiber-reinforced backfill under different proportion conditions first appeared in the central low-strength zone, and then gradually extended to the two ends, eventually leading to the overall failure. As the axial strain increases, the total and dissipated energies of glass fiber-reinforced backfill specimens increase as an exponential function, and the elastic energy increases and then decreases with the peak strain as the node. The bond between the glass fiber and the mortar matrix interface allows the fibers across both sides of the crack to form an “anchoring” effect, thus improving the overall properties of the backfill. The results of the study can promote the application and exploration of glass fiber-reinforced backfills in mine filling and provide some reference for improving the backfill performance.

19

Moduł sprężystości międzywarstwy w projektowaniu szkła

Stevels Wim

Świat Szkła

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2023

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R. 28, nr 1

40--44

20

Quasi-Static Investigations of 240-Bloom Gelatine for Ballistic Tests

Fikus Bartosz, Basiński Norbert

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

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2023

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Vol. 14, Nr 1 (51)

61--72

EN

The paper presents the results of investigations of ballistic gel properties in quasi-static conditions. Specimens were prepared using the 240 Bloom gelatine, which was determined by product availability. Tests were carried out making use of a material testing machine to estimate the influence of gel share on stress-strain characteristics. Considered values of a gel mass content were equal to 10, 12, and 14%. Assumed parameters were determined on the material calibration stage conducted with steel balls with a diameter of 4.5 mm. The most significant influence of a gel content on mechanical properties of specimens were observed for a share of 10% and 12%. The conducted preliminary tests are a part of investigations aimed at assessment if it is possible to calibrate the ballistic gel making use of mechanical characteristics obtained in quasi-static tests without shooting.

PL

Niniejsza praca stanowi opis oraz wyniki prac realizowanych w ramach badań quasi-statycznych żelatyny (o sile żelowania 240 Bloom) przeznaczonej do testów balistycznych, która jest najczęściej stosowanym substytutem tkanek miękkich w badaniach balistyki końcowej. W ramach prac przeprowadzono proces przygotowania materiału do badań, jego kondycjonowania, kalibracji oraz badań w warunkach quasi-statycznych w celu określenia modułu sprężystości wzdłużnej oraz modułu sprężystości objętościowej. Na podstawie wstępnych badań kalibracyjnych podjęto decyzję o przebadaniu próbek o zawartości żelatyny równej 10 %, 12 % oraz 14 %. Rezultaty badań (krzywe siła-przemieszczenie) pozwoliły na ocenę odkształceń oraz naprężeń (inżynierskich oraz rzeczywistych) występujących w badanym materiale. To z kolei pozwoliło na ocenę wartości wyżej wspomnianych modułów sprężystości. Należy zwrócić uwagę na relatywnie duży rozrzut uzyskanych wyników, co może sugerować konieczność dalszych prac nad precyzją wykonania próbek. Uzyskane wyniki wykazały łatwość oraz efektywność zastosowanej metodyki przygotowania próbek, jak również znaczący wpływ zawartości żelatyny na moduł sprężystości wzdłużnej (szczególnie w przypadku dwóch niższych wartości zawartości żelatyny). Zdecydowania mniejszą rozbieżność zauważono w przypadku modułu sprężystości objętościowej. Ponadto, okazało się, że przygotowanie próbek o udziale masowym 20 % jest nieuzasadnione ze względu na dużą czasochłonność całości procesu.