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1

Influence of corrosion degradation on the dynamic response of steel plates

Zima Beata, Roch Emil, Mikulski Tomasz, Wójcik Michał

Polish Maritime Research

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2025

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nr 2

132--140

EN

Corrosion, particularly in marine and offshore environments, often leads to material loss and surface irregularities that compromise structural integrity. Traditional non-destructive testing methods, such as ultrasonic thickness measurements, are limited in regard to detecting widespread or irregular corrosion damage. This study explores the use of vibration-based analysis to assess the effects of corrosion by examining changes in the dynamic behaviour—specifically, the natural frequencies—of steel plates. Numerical simulations are conducted using Abaqus that include random surface irregularities, modelled with Gaussian random fields, to represent generalised corrosion. Experimental validation involves steel plates subjected to accelerated electrochemical corrosion, with degradation assessed based on mass loss and ultrasonic thickness measurements. Changes in modal parameters due to progressive corrosion are recorded using impact hammer excitation and accelerometers. The results show a clear relationship between corrosioninduced thickness reduction and shifts in modal characteristics. The findings demonstrate that modal analysis offers a viable, non-invasive method for detecting and evaluating global corrosion damage in large-scale steel structures.

2

Reverse Engineering and Computer Modelling in Archaeometallurgy for the Reconstruction of Heritage Objects Using Precision Casting and 3D Printing

Marlicka Karolina, Fijołek Andrzej, Garbacz-Klempka Aldona, Piękoś Marcin

Journal of Casting & Materials Engineering

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2025

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Vol. 9, no. 4

72--79

EN

This article presents an interdisciplinary approach to the reconstruction of a copper-alloy artefact using reverse engineering techniques combined with modern digital and manufacturing technologies. The research was motivated by the need to better understand historical casting techniques while preserving the integrity of cultural heritage objects through non-destructive methods. The study integrates 3D scanning, CAD-based modelling, numerical simulations, investment casting, and metal additive manufacturing. The geometry of the artefact was captured using high-resolution 3D scanning, enabling the development of two CAD models: one representing the preserved state of the object and a second reconstructed model with the missing fragment digitally restored. Both models were used for numerical simulations of mould filling, solidification, cooling, and porosity formation performed in MAGMASOFT® 6.1, allowing the assessment of technological feasibility and defect formation. Based on the simulation results, physical replicas were produced using investment casting and selective laser melting. The obtained numerical and experimental results were compared in terms of geometry reproduction, surface characteristics, and predicted versus observed casting behaviour. The study demonstrates that the combination of digital reconstruction, simulation tools, and experimental manufacturing provides a reliable framework for analysing historical metallurgical processes. The proposed methodology supports both scientific interpretation and the practical reconstruction of heritage objects and can be applied to a wide range of archaeometallurgical studies.

3

Development of ultrasonic technique using phased array probes in type IV low-pressure tank

Kozera Paulina, Sarniak Łukasz, Dydek Kamil, Wolanin Andrzej, Boczkowska Anna

Composites Theory and Practice

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2025

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R. 25, nr 4

234--242

EN

The aim of this work is to develop an ultrasonic technique employing phased array probes to detect structural defects in type IV low-pressure tanks used for the storage of hazardous chemicals. Ultrasonic testing was performed by means of an OmniScan MX2 phased-array ultrasonic flaw detector with appropriate probes, and numerical simu lations were conducted utilizing CIVA software. Attenuation coefficients were measured for a composite layer excised from a two-layer low-pressure tank. Based on these results, a centre frequency of 5 MHz was selected as optimal. The determined parameters, such as the attenuation coefficient and the structural noise level, were implemented in the CIVA model. The detection criteria were established and color-coded: defects with a signal-to-noise ratio (SNR) < 0 dB were labelled white (undetectable); those 0-10 dB were labelled yellow (limited detectability); and those > 10 dB were labelled green (optimal detectability). The simulation results were validated by testing the composite samples with polytetrafluoroethylene (PTFE) inserts of varying sizes and depths. The defect detectability determined from the simulations was consistent with that obtained from testing reference samples.

4

Analysis of the possibility of using the Sankey diagram in the diagnosis of a partially loaded diesel engine

Puzdrowska Patrycja, Skobyłko Jakub

Combustion Engines

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2025

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R. 64, nr 3

58--66

EN

The purpose of this article is to determine if, in the case of inability to carry out diagnostic tests at engine operating loads in the range of 70-90%, engine functional systems can generate diagnostic signals in the form of changes in heat balance components. The motivation for working on the selected topic was the need to evaluate the effectiveness of graphical forms of heat balance representation, especially Sankey diagrams, in heat engine diagnostics, using a four-stroke diesel engine as an example. Interpretation of the results was carried out based on simulations performed using Blitz-PRO software and experimental tests carried out on a test bench. For the numerical simulations, the object under analysis was modeled, which was a single-cylinder, four-stroke diesel engine Andoria S320. Both numerical simulations and experimental tests were carried out for three engine operating states: the reference state and two malfunction states: in the air intake system and the fuel supply system. The analyses made it possible to draw conclusions. It was assessed that carrying out the analysis of the Sankey diagram for partial load doesn’t bring significant diagnostic information.

5

Modal analysis of a beam with a metamaterial segment produced using additive manufacturing technology

Ciborowski Tomasz, Wojtczak Erwin, Rucka Magdalena

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 8

359--372

EN

The paper focuses on the analysis of the dynamic response of the mechanical metamaterials manufactured using 3D printing technology. A modal analysis of a cantilever beam with a metamaterial segment was conducted to evaluate the influence of the segment geometry on the dynamic parameters of the structure, such as natural frequencies and mode shapes. A method allowing to include the effect of the actual stiffness of the beam support in the numerical model using elastic constraints was also proposed. The significant influence of the geometry of the metamaterial segment on the dynamic behaviour of the tested beam was proved. The research findings provided new insights that are significant for potential applications of metamaterials in civil engineering.

6

Experimental and numerical study on the effectiveness of the barrier protecting explosive against electric initiation systems

Żochowski Paweł, Krysiński Bogdan, Bagrowski Jan, Borkowski Jacek

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 1

333--348

EN

Improvised explosive devices are responsible for death and injury of thousands of people (both civilians and soldiers) annually. They are often produced by simple home-made modifications of the old artillery shells. One of the ways of preventing modification of currently used artillery shells intended to make it more difficult to use as IEDs was analyzed in the article. A special safety barrier placed between the fuse and the explosive in order to block the access to the explosive after unscrewing the fuse was proposed. The barrier was used also to protect explosive against detonation with commonly used electric initiation systems. Therefore the main aim of the analyses presented in the article was to determine a critical barrier thickness for which the acceptor has 50% probability of being detonated. The research included experimental gap-tests as well as numerical reproduction of the phenomenon in the Impetus AFEA software. Various types of electric initiation systems were analyzed differing with material of the body, type and amount of explosive used as well as the shape of the frontal part of the detonator (flat or with hemispherical cavity). Critical barrier thicknesses were determined for individual variants of donor-gap-acceptor systems. Numerical model of the phenomenon was defined and validated against experimental data. Small differences between the experimental and numerical results allow to use the model to initial evaluation of the effectiveness of different barrier variants.

7

Investigation of flow features and acoustic radiation of a set of rectangular cavities in a channel

Łojek Paweł, Suder-Dębska Katarzyna

Vibrations in Physical Systems

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2024

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Vol. 35, nr 1

art. no. 2024110

EN

This article focuses on a noise of aerodynamic origin, generated by the flow over single and multiple rectangular cavities. The paper presents the methodology and results of the conducted numerical simulations of the air flow in a channel with a set of rectangular cavities. The aeroacoustic wave equation was used to determine the acoustic pressure generated by the flow. Various configurations of the cavities made it possible to study the influence of their reciprocal location on the generated sound. The research showed that as the distance between the cavities decreased, the acoustic pressure levels increased. They were several decibels higher than for the single-cavity case.

8

Acoustic aspects of the Goseck Circle area

Suder-Dębska Katarzyna

Vibrations in Physical Systems

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2024

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Vol. 35, nr 2

art. no. 2024213

EN

This article presents a study conducted to evaluate the acoustic quality of the Goseck Circle, an ancient circular enclosure, also known as a rondel, situated in Saxony, Germany. Goseck Circle is an example of monumental buildings from the Neolithic period, which are called rondels. The facility was discovered in the 1990s. Then the facility was archaeologically reconstructed and opened to the public in 2005. Currently, it is considered to be the oldest known structure of this type, and its creation is estimated at around 4900 BC. Goseck Circle is roughly of a circular shape. It has one ditch and two palisade rings. There are three entrances leading to the interior of this facility. Therefore, the Goseck Circle is considered as the oldest solar observatory, as a worship, or a ritual place. A number of studies on both contemporary and archaeological facilities indicate that the facilities display the characteristic features depending on their intended use. Therefore, it can be assumed that if the Goseck Circle was to be a place of worship, then in terms of the acoustic aspects, it should be characterized by such values of the acoustic parameters, that will also prove this. This concept was the reason for carrying out a series of numerical calculations that allowed for the determining of the selected parameters characterizing the acoustic field inside the analysed facility.

9

Analiza wpływu minimalnej różnicy temperatury w wymienniku ciepła zanieczyszczonym osadami na nastawy regulatora temperatury PID

Markowski Mariusz, Alabrudziński Sławomir, Trzciński Przemysław, Szreder Mariusz

Przemysł Chemiczny

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2024

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T. 103, nr 12

1509--1513

PL

W eksploatacji wymienników ciepła jednym z bardziej uciążliwych uwarunkowań przemysłowych są osady powstające na powierzchni wymiany ciepła. Powszechnie wiadomo, że osady powodują straty ciepła. Ponadto w miarę upływu czasu zmienia się dynamika wymiennika ciepła, co wymusza okresowe dostrajanie nastaw regulatorów temperatury PID. W celu zmniejszenia negatywnych skutków oddziaływania osadów na eksploatację wymienników ciepła zaproponowano nowy sposób ich obliczeń cieplno-przepływowych poprzez odpowiedni dobór minimalnej różnicy temperatury w wymienniku (ΔTmin) na etapie projektowania. W tym celu wykonano symulacje numeryczne wykorzystujące model płaszczowo-rurowy wymiennika ciepła w stanie dynamicznym. Na podstawie obliczeń numerycznych wymiennika przeanalizowano wpływ oddziaływania osadów na nastawy regulatora temperatury PID w zależności od ΔTmin.

EN

In order to reduce the neg. effects of fouling on the operation of heat exchangers, a new method of thermal calcns. was proposed by appropriate selection of the min. temp. difference in the exchanger (ΔTmin) at the design stage. A series of numerical simulations were performed using a shell-and-tube heat exchanger model in a dynamic state. Based on numerical calcns. of the exchanger, the impact of fouling on the PID temperature controller settings was analyzed depending on ΔTmin.

10

Formation of methane hazards during underground coal production in the longwall area ventilated by System Y

Tutak Magdalena

Production Engineering Archives

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2024

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Vol. 30, Iss. 3

394--405

EN

The article addresses a critical and timely issue: improving safety in underground coal mining. The primary objective of the paper was to develop a research methodology based on modelling studies to identify and assess the state of methane hazards during mining operations. To achieve this, structural modelling of the physical and chemical phenomena occurring in mining regions was conducted using Computational Fluid Dynamics. The core research was performed using the finite volume method on a real longwall exploitation site ventilated by a Y-system. This approach enabled the determination of methane and oxygen concentration distributions in the mining region and goafs, treated as a porous and permeable medium. Based on these findings, potential fire and/or methane explosion hazard zones were identified in the goaf. The model test results underwent a validation process, comparing them with actual measurements. The determined errors were within an acceptable range, confirming the accuracy of the developed model of the mining region and the phenomena within it. Furthermore, the model was used to predict the locations of zones at risk of fire and/or methane explosion in the goafs, particularly in areas with potentially increased gas emissions. The results clearly demonstrate the significant potential of using model studies to diagnose and forecast methane hazards in underground mining operations. Identifying these potential danger zones allows for the implementation of preventive measures to reduce the likelihood of dangerous incidents.

11

Progress in modelling and simulation of the machining process - part II: Mesh-free modelling and simulation

Grzesik Wit

Mechanik

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2024

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R. 97, nr 5-6

6--15

EN

In this paper some rules of mesh-free/meshless modelling and numerical simulations of fundamental physical phenomena associated with the machining process, including mechanisms of plastic deformation, chip formation and interfacial friction are overviewed. Some representative examples of the mesh-free modelling application to material removal processes at different scales, i.e.: machining processes, water jet-assisted processes, additive machining processes and simulation of micromachining processes using predominantly SPH (smoothed particle hydrodynamics) method are given.

PL

W artykule omówiono zasady bezsiatkowego modelowania i symulacji numerycznej podstawowych zjawisk fizycznych towarzyszących procesom obróbki, w tym mechanizmów odkształcania materiału, tworzenia wióra i tarcia. Podano przykłady zastosowania bezsiatkowego modelowania procesów obróbki ubytkowej, m.in.: obróbki skrawaniem, wysokociśnieniową strugą wody (WJM i AWJM) oraz obróbki i symulacji mikroobróbki z użyciem metody SPH (hydrodynamiki wygładzonych cząstek).

12

Progress in modelling and simulation of the machining process - part I: Multiscale modelling

Grzesik Wit

Mechanik

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2024

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R. 97, nr 3

30--37

EN

In this paper some rules of a multiscale modelling and numerical simulations of fundamental physical phenomena associated with the machining process, including mechanisms of plastic deformation, chip formation and interfacial friction are overviewed. Some representative examples of the modelling application to multiphase and composite materials, determination of constants in the material constitutive equations and simulation of nano- and micromachining processes using MD-FEM and SPH-FEM hybrid methods are given.

PL

W artykule omówiono zasady wieloskalowego modelowania i symulacji numerycznej podstawowych zjawisk fizycznych towarzyszących procesowi skrawania, w tym mechanizmów odkształcania materiału, tworzenia wióra i tarcia. Podano przykłady zastosowania modelowania materiałów wielofazowych i kompozytowych, wyznaczania stałych materiałowych w równaniu konstytutywnym oraz symulacji mikro- i nanoobróbki z użyciem hybrydowej metody MD-FEM i SPH-FEM.

13

Fractional optimal control approach to the diabetics model

Nadeem Muhammad, Habib Mustafa, Arif Ayesha, Asjad Muhammad Imran

Journal of Applied Mathematics and Computational Mechanics

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2024

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Vol. 23, nr 1

71-82

EN

Diabetes mellitus is one of the most critical diseases, affecting millions of people around the world. This work deals with the fractional optimal control of the dynamics of the population model on diabetes. This framework is based on the fractional order differential problems that describe the population before and after diabetes involving some health problems. We consider the Caputo derivatives for the study of the proposed model. The maximum principle of Pontryagin is utilized to derive the necessary conditions for the optimality of a dynamical system. Using a forward-backward sweep approach with the generalized Euler method accomplishes numerical solutions of formulated issues.

14

Exploring the dynamics of monkeypox: a fractional order epidemic model approach

Baba Isa Abdullahi, Hincal Evren, Rihane Fathalla A.

Journal of Applied Mathematics and Computational Mechanics

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2024

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Vol. 23, nr 1

32-44

EN

We present a mathematical model employing nonlinear fractional differential equations to investigate the transmission of disease from rodents to humans. The existence and uniqueness of the model’s solutions are established through Banach contraction maps, and the local asymptotic stability of equilibrium solutions is confirmed. We calculate a critical parameter, the basic reproduction number, which reflects secondary infection rates. Numerical simulations illustrate dynamic changes over time, showcasing that our model provides a more comprehensive representation of the biological system compared to classical models.

15

Failure analysis of fibre metal laminate channel section column under axial compressive pulse loading

Zaczynska Monika

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 5

art. no. e151048

EN

The study aims to analyse the dynamic buckling phenomenon and assess the role of the stress tensor components in the failure process of a short fibre metal laminate column under axial compressive dynamic loading. The investigation is focused on a channel-section profile composed of three aluminium layers and two doubled composite plies [Al/0/90/Al/90/0/Al]. The numerical analysis was performed on the finite element model, which was validated by experimental static buckling tests. Employing a progressive failure algorithm, this analysis incorporated the material property degradation method and Hashin’s criterion as the damage initiation criterion. Failure initiation in metal layers was based on the Huber-Mises-Hencky failure criterion. Based on the conducted analyses, it was concluded that the dominant forms of destruction in the FML structure are yielding in the metal layers due to excessive compressive stresses and the failure of the matrix in composite plies as a result of compressive and shear stresses. Through a thorough examination of the stress tensor components, critical stresses contributing to aluminium plastic deformation and laminate failure mechanisms were identified.

16

Experimental and numerical investigations on polycarbonate samples and rotorcraft windshield for bird model impacts

Ćwiklak Janusz, Gołda Paweł, Goś Artur, Kobiałka Ewelina, Krasuski Kamil

Archives of Transport

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2024

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Vol. 70, iss. 2

79--96

EN

One of the factors that significantly affect flight safety is bird strikes. Various aircraft parts are vulnerable to damage. For helicopters, the windshield, the front part of the fuselage, and the rotor blades are particularly sensitive to bird collisions. Experimental studies and numerical modelling of bird model impacts on polycarbonate samples and a helicopter windshield are presented in the paper. For the tests, a gelatine projectile was used as a bird substitute. In numerical studies, it was represented by a cylindrical shape with hemispherical ends. In the first stage of the experimental tests samples made of polycarbonate material were used as a target. These studies focused on determining the sample deflections and velocity at which the bird model would penetrate the target. The experimental investigations were conducted with a special set-up of a gas gun equipped with high-speed cameras, tensiometers, accelerometers, and force sensors. The simulations were conducted using LS-DYNA software by applying the SPH method to the bird model. The test stand models were developed in a CAD environment and then imported into LS-Pre Post software, where they were discretized to use in numerical analyses. Results of the studies, such as impact force, acceleration, and windshield deflection were compared. Besides, the high-speed cameras allowed visualization of the impact process. It turned out that both a polycarbonate plate and a helicopter windshield were punctured at the speed of 50 m/s. It can be noted that the curves of the impact force and the deflection of samples obtained as a result of numerical analysis correlated well with the empirical ones. The correlation validated the modelling parameters and confirmed that numerical simulations could be trusted as an effective and reliable method for analyzing materials' behavior under impact loading.

17

Numerical behavior for quasi static thermoelasticity without positive definite elasticity

Baldonedo J., Fernández J. R., Quintanilla R.

Archives of Mechanics

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2024

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Vol. 76, nr 6

497--514

EN

This paper presents a numerical study of the energetic behavior of some quasi-static thermoelastic problems in one- and two-dimensional settings. Firstly, we describe the two-dimensional thermoelastic problem decomposing the elastic tensor into two parts: the first one is positively defined for the first component of the displacement field, and the second one is negatively defined for the second component. The variational formulation is also derived. Restricting ourselves to the one-dimensional setting and assuming that the elastic coefficient is negative, we prove that the exponential energy decay follows if the coupling coefficient is smaller than the square root of the product between the heat capacity and the elastic coefficient. Then, fully discrete approximations are introduced by using the finite element method and the implicit Euler scheme. Some numerical simulations are performed: in a first onedimensional example, we show the decay of the discrete energy depending on the value of the coupling coefficient and the heat diffusion. Secondly, two dimensional studies are considered depending on the expression of the elastic tensors, including diagonal matrices with the same eigenvalue, diagonal matrices with different eigenvalues and full matrices.

18

Adaptation of public spaces to climate change case study of Lodz

Bochenek Anna, Klemm Katarzyna, Stefańska Magdalena

Architecture Civil Engineering Environment

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2024

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Vol. 17, no. 4

129--145

EN

Climate change is nowadays one of the most important problems that affects urban areas, where over half of the population lives. Due to the continuously growing population, significant number of citizens will be affected by its impact. For this reason, one of the steps to adapt cities to changing climate conditions is the implementation of adaptation strategies based on blue-green infrastructure elements. In this article, the existing conditions of two selected public spaces in Lodz (Poland) and the impact of the proposed modernization projects were examined. The aim of the study was to determine the extent to which the proposed projects will improve microclimatic conditions and thermal comfort, and to select a more efficient urban planning option. Simulations of meteorological conditions and thermal comfort for representatives of four groups of space users were done by using the ENVI-met program. This study reveals the relevance of the thermal comfort subject, especially for people over 65 years of age, due to the increased sensations of elderly during high temperatures and the increasing participation of this demographic group in the population of Lodz.

19

Stability of Thin-Walled Composite Structures with Closed Sections Under Compression

Rosłaniec Kuba, Różyło Patryk

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 3

188--199

EN

The purpose of the research was to analyze the experimental-numerical influence of the type of cross-section on the stability of thin-walled composite columns with closed (rectangular) cross-sections. The subject of the investigation was thin-walled composite structures made of CFRP composite (carbon fiber reinforced polimer), characterized by a closed rectangular cross-section shape of the profile and a identical ply configuration. In this study, experimental and numerical investigations of axially compressed columns were performed to determine the values of buckling loads and buckling forms. Experimental investigations were performed using a universal testing machine with an optical deformation measurement system. In parallel with the experimental tests, numerical simulations were made using the FEM (Finite Element Method). The numerical studies conducted using dedicated numerical models and the experimental studies made it possible to carry out a thorough analysis of the impact of the cross-sectional shape on the buckling phenomenon of the structure. The novelty of the present paper is the use of interdisciplinary testing methods to compare the effect of cross-sectional geometry on the stability of thin-walled composite columns.

20

Evaluation of frictional wear in a follow-up screw-rod kinematic node in GGS transpedicular stabilization

Lichosik Justyna, Szkoda-Poliszuk Klaudia, Żak Małgorzata, Pezowicz Celina

Acta of Bioengineering and Biomechanics

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2024

|

Vol. 26, no. 3

135--146

EN

The aim of this study was to evaluate the abrasive wear of the sliding screw-rod joint used in growth guidance system (GGS) stabilizers, allowing for the translation of the screw along the rod during the spinal growth process in a standard and modified system. Methods: The study used single kinematic screw-rod pairs made of titanium alloy Ti6Al4V. Mechanical tests (cyclic loads) simulated the stabilizer’s operation under conditions similar to actual use. A microscopic evaluation was conducted, analyzing abrasive wear based on measured abrasion areas. Numerical simulations were performed for the standard joint system and for a structural change (an additional insert to increase contact area between the rod and sliding screw cap). Results: The study evaluated the abrasive wear of the mating elements of the stabilizer. Mechanical tests showed an increase in the force observed (11.74 ± 2.52 N) with the increasing number of load cycles. Microscopic evaluation showed abrasion of the caps and rods in two areas (upper and lower). Numerical simulations indicated the highest stresses in the standard system were on the mating elements, i.e., the rod and the cap (15.6 MPa). In the modified joint, stress distribution differed, concentrating on the surface of the insert and the rod, with maximum values of 6.0 MPa (PE insert) and 12.4 MPa (PEEK insert). Conclusions: Comparing the stress distributions obtained in the numerical simulations and the abrasive wear effects produced in the mechanical tests, a similar mechanism was observed (the destruction of the top layer of the mating elements of the stabilizer).