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  1. 9 Civil and Environmental Engineering Reports
  2. 8 Archives of Civil and Mechanical Engineering
  3. 6 Fatigue of Aircraft Structures
  4. 4 Czasopismo Techniczne. Budownictwo
  5. 4 Modelling in Engineering
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  1. 7 Katunin A.
  2. 6 Lorenc W.
  3. 3 Kożuch M.
  4. 3 Polus Ł.
  5. 3 Szumigała M.
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1
Content available Experimental and finite element analysis of PPF controller effectiveness in composite beam vibration suppression
Mitura Andrzej, Gawryluk Jaroslaw
Eksploatacja i Niezawodność
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2022
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Vol. 24, no. 3
468--477
EN
In this paper the problem of vibration reduction is considered. Generally, mechanical vibrations occurring during the operation of a system are undesirable and may have a negative effect on its reliability. A finite element model of a single active blade is developed using the Abaqus software. This structure consists of a multi-layer glass-epoxy composite beam with an embedded macro fiber composite (MFC) piezoelectric actuator. For vibration control the use of a positive position feedback (PPF) controller is proposed. To include the PPF controller in the Abaqus software, a special subroutine is created. The developed control algorithm code makes it possible to solve an additional differential equation by the fourth order RungeKutta method. A numerical dynamic analysis is performed by the implicit procedure. The beam responses with and without controller activation are compared. The control subsystem model also includes the hysteresis phenomenon of the piezoelectric actuator. Numerical findings regarding the PPF controller’s effectiveness are verified experimentally.
2
Content available remote The Use of GFRP Tubes as Load-Bearing Jackets in Concrete-Composite Columns
Abramski Marcin, Chmielnicki Błażej
Civil and Environmental Engineering Reports
|
2022
|
Vol. 32, no. 2
96--117
EN
The paper presents the fields of applications of polymer composites in building structures. The use of composite glass fibre tubes is discussed in more detail. The laboratory methods used to test the mechanical properties of these pipes are presented. An original research program is presented, including six concrete-filled glass fibre tubes. The cylinders and columns made in this way were tested for their axial load capacity. Conclusions were formulated regarding the relationship between the load-bearing capacity of the test elements and their length, as well as the angle of glass fibres arrangement in the tube composite.
3
Content available Assessment of adhesively bonded joints of aluminum sheets for application as the core of composite beams
Derlatka Anna
Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo
|
2021
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Z. 27 (177)
30-36
EN
The paper presents an evaluation of joints resulting from adhesively bonded aluminum sheets. The aim of the study was to assess the possibility of applying this type of connection for the construction of composite beams. The results of experimental tests on the shear test of joints are presented. Four types of connectors were the subjects of the research. The joints of the same geometry were made of four 1.6 mm thick sheets of aluminum alloy AA 7075-T6. Each type of joint was characterized by a different material joining the sheets: three of them were connected by acrylic foam tapes, one joint was made using two component toughened methacrylate adhesive. Three different double-sided acrylic foam tapes with different properties were tested. It has been assessed that the two-component toughened methacrylate adhesive can be used for the construction of the aluminum core applied in composite structures.
PL
Dokonano oceny połączeń aluminiowych blach w wyniku adhezji. Celem pracy była ocena możliwości zastosowania tego typu połączeń do budowy belek kompozytowych. Zaprezentowano wyniki badań eksperymentalnych z próby ścinania złączy. Przedmiotem badań były cztery rodzaje złączy. Złącza o identycznej geometrii zbudowano z czterech blach ze stopu aluminium AA 7075-T6 o grubości 1.6 mm. Każdy typ złącza charakteryzował się innym materiałem łączącym blachy: trzy z nich połączono za pomocą akrylowych taśm piankowych, jedno złącze powstało z wykorzystaniem dwuskładnikowego, utwardzanego metakrylowego kleju. Przebadano trzy różne dwustronnie klejące akrylowe taśmy piankowe różniące się właściwościami. Oceniono, iż do budowy konstrukcji kompozytowych opartych na bazie trzonu aluminiowego istnieje możliwość zastosowania dwuskładnikowego, utwardzanego metakrylowego kleju.
4
Content available Application of Digital Radiography (Dr) in an Approach to Evaluate the Technical Condition of MiG-29’s Vertical Stabilizers
Luziński Rafał, Synaszko Piotr, Dragan Krzysztof
Fatigue of Aircraft Structures
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2021
|
Iss. 13
1--7
EN
The purpose of the work presented was to evaluate the capabilities of digital radiography to detect cracks in the internal structure of MiG-29 vertical stabilizers. The test object was a stabilizer previously subjected to fatigue testing and partially torn down for the needs of visual inspection. An inspection of three regions containing cracked parts was performed, with use of a pulsed x-ray generator and digital detector array. The results confirmed the method could be used to detect cracks in an internal structure which could not be inspected with other methods without affecting the stabilizer’s integrity.
5
Content available Performance-based Design and Construction of the “World Class” Gym in Minsk using Innovative Structural Solutions
Tur Andrei V., Tur Viktar V., Tsymbarevich Tsimafei A.
Modern Engineering
|
2020
|
2
50--61
EN
The article presents the result of the implementation of innovative design solutions techniques during the construction of the building of the “WORLD CLASS” Fitness Club in Minsk with usage of the performance-based approach. Proposed design solution of building include the composite structures (plane frames consists of steel-concrete columns and delta-beam), prestressed hollow core slabs. The cantilever parts of the building were designed as a complex post-tensioned monolitic structure, including cantilever beams and slabs with a maximum length of 12 m, monolitic walls and pylons. The example of performance criteria verification (structural serviceability) with usage different methods presents.
6
Content available On the Identification of Local Structural Defects in Composite Thin-Walled Structures
Kopecki Henryk, Święch Łukasz, Kołodziejczyk Radosław
Advances in Science and Technology. Research Journal
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2020
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Vol. 14, no 1
154--166
EN
The presented work considers the issue of the usefulness of alternative methods aimed at quickly and effectively identifying the local damage to the thin-walled composite load-bearing structures. Two ways of identifying destruction were considered, based on the assumption that the damage that occurs during operation causes local changes in the system rigidity. The first method is based on strain gauges. It consists of embedding strain gauges in the structure at the stage of composite production and monitoring of deformation during its life cycle. The second of the concepts under consideration is based on modal analysis, carried out using a modal hammer. On the example of the plate band, experimental studies supported by numerical analysis were carried out. The obtained research results and numerical analyses allowed for the formulation of a number of conclusions, mainly in terms of focusing on further research.
7
Content available Evaluation of the Mechanical Parameters of Ultrasonically Welded Textile Composite Structures for Protective Footwear
Irzmańska Emilia, Majchrzycka Katarzyna, Adamus-Włodarczyk Agnieszka, Brochocka Agnieszka
Fibres & Textiles in Eastern Europe
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2019
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Vol. 27, no. 3 (135)
99--105
EN
Textile materials are used in protective footwear due to their good mechanical and hygienic properties and to provide thermal insulation. This work presents a technological process of designing ultrasonically welded composite structures characterised by various densities of welding spots. The study involved three variants of composite structures made of three layers. The composite structures developed were tested in terms of mechanical properties and were statistically analysed in terms of the effects of welding spot density and reinforcing nonwoven thickness on the protective parameters. Inserts made of ultrasonically spot-welded textile composite structures may offer protective footwear users greater comfort in terms of mechanical resistance. The evaluation method proposed may be a useful tool in assessing textile composite structure inserts for protective footwear.
PL
Tekstylne materiały kompozytowe są używane w obuwiu ochronnym do poprawy m.in. właściwości mechanicznych. W pracy przedstawiono analizę wpływu różnej gęstości punktów zgrzewających wykonanych metodą ultradźwiękową na parametry mechaniczne kompozytów pod kątem zastosowania ich w obuwiu ochronnym w postaci wkładek. Do badań wytypowano trzy warianty kompozytów będących przestrzenną strukturą utworzoną konstrukcyjnie z trzech różnych morfologicznie warstw włókienniczych. Statystycznie udowodniono, że możliwa jest poprawa tych właściwości poprzez zastosowanie optymalnej gęstości zgrzewów o określonej średnicy i rozmieszczanych regularnie, podczas procesu zgrzewania. Zaproponowany sposób oceny uwzględniający ocenę trzech kluczowych, z punktu widzenia użytkowania obuwia, parametrów mechanicznych (ścieranie, oddzieranie warstw i sztywność zginania) może być przydatnym narzędziem podczas oceny tekstylnych kompozytowych wkładek do obuwia ochronnego.
8
Content available A Comparison of Composite Specimens Damage area Measurements Performed using Pulsed Thermography and Ultrasonic NDT Methods
Luziński Rafał, Ziemkiewicz Jarosław, Synaszko Piotr, Żyluk Andrzej, Dragan Krzysztof
Fatigue of Aircraft Structures
|
2019
|
Iss. 11
68--77
EN
Carbon fiber reinforced plastics (CFRPs) are widely used in aerospace structures due to their high stiffness, strength and good fatigue properties. They are however vulnerable to loads perpendicular to their plane and, while impacted, can suffer significant internal damage decreasing their overall strength. Detecting and sizing such damage is an important task of the non-destructive inspection (NDI) methods. This study was conducted to detect and quantify damage in a set of six impacted even rectangular CFRP specimens designed from a MiG-29 vertical stabilizer’s skin. The inspection was done using the ultrasonic (UT) method (based on mobile scanner – MAUS V) and the pulsed infrared thermographic (IRT) method. Each specimen’s inside and outside (impacted) surface was inspected separately with IRT, while the outside surface was then inspected with UT. UT provided the most precise measurements of the damage area, while the IRT inspection of the outside surface (which would be accessible on a real aircraft structure) provided underestimated values due to the damage’s depth and geometry.
9
Content available remote The development of arc stud welding
Kapler Mateusz, Nowacki Jerzy, Sajek Adam
Biuletyn Instytutu Spawalnictwa w Gliwicach
|
2019
|
Vol. 63, No. 4
27--38
EN
The article analyses the origins and initial stages of the development of the drawn arc welding of steel studs. The analysis is focused on the evolution of welding-related professional terminology in various languages. The article presents the properties and areas of application of shear connectors – some of the most popular connectors, used particularly often in civil engineering investments.
PL
Przeprowadzono analizę historycznych początków i wstępnych etapów rozwoju technologii zgrzewania kołków stalowych łukiem ciągnionym. Dokonano przeglądu ewolucji różnojęzycznej terminologii branżowej. Przedstawiono właściwości oraz aktualne obszary zastosowań kołków gładkich z łbem – jednego z najpowszechniejszych rodzajów tego typu wyrobów we współczesnym przemyśle, wykorzystywanych szczególnie często w przedsięwzięciach inżynierii lądowej.
10
Content available remote Possibilities of using production tests of the arc welding of pins in the qualifying of operators
Kapler Mateusz, Nowacki Jerzy, Sajek Adam
Biuletyn Instytutu Spawalnictwa w Gliwicach
|
2019
|
Vol. 63, No. 6
17--23
EN
The study discussed in the article involved the analysis of standard-related conditions concerning the qualification testing of stud welding operators. Special attention was paid to the licensing of personnel making welds of shear connectors using drawn arc and ceramic ferrules. The authors emphasized the risk of technical standards misiterpretation and its financial consequences. The study also focused on frequent approaches to examinations by examining bodies. The final part of the article indicates the existence of legally effective methods enabling the production test-based qualification of production personnel.
PL
Dokonano analizy uwarunkowań normatywnych odnoszących się do egzaminowania kwalifikacyjnego operatorów zgrzewania łukowego kołków stalowych. Szczególną uwagę poświęcono kwestiom uprawnień personelu do wykonywania zgrzein kołków gładkich z łbem łukiem ciągnionym z poderwaniem i użyciem pierścieni ceramicznych. Podkreślono ryzyko błędnej interpretacji przepisów technicznych dotyczących badania technologii i związanych z tym konsekwencji finansowych. Przedstawiono częste podejście jednostek egzaminujących w tym zakresie. Wreszcie, wskazano na możliwość prawnie skutecznego kwalifikowania pracowników na podstawie badania produkcyjnego.
11
Content available remote Seismic behavior of concrete-filled double-skin steel tube/moment-resisting frames with beam-only-connected precast reinforced concrete shear walls
Hu Yi, Zhao Junhai, Zhang Dongfang, Chen Yanxiong
Archives of Civil and Mechanical Engineering
|
2019
|
Vol. 19, no. 4
967--980
EN
Concrete-filled double-skin steel tube (CFDST) attracts attention from researchers for it exhibits high strength, good ductility and energy dissipation capacity. In this paper, CFDST frame with beam-only-connected precast reinforced concrete shear wall system is pro-posed, and all the joints used high-strength bolt connection to realize fully-prefabricated construction. Three specimens were tested to obtain the seismic performance and coopera-tive mechanism of such proposed systems, and the contribution of beam-only-connected precast reinforced concrete shear wall (BRW) was quantified by comparing the results of these specimens. The results show that: (1) the BRW cooperated well with the CFDST frames, and it significant enhanced the lateral stiffness and strength of the CFDST frame; (2) all specimens tolerated more than 4% inter-story drift ratio, indicating that the specimens have good lateral deformation capacity; (3) the specimen with two pieces of BRW (BF-BRW-B) exhibited better ductility ratio by comparing with the specimen without BRW (BF) and with only one piece of BRW (BF-BRW-A); (4) relative brittle failure was occurred on the BRW in BF-BRW-A due to the shear force, which resulted in significant strength degradation and ductility reduction of the specimen, but two BRWs in BF-BRW-B could mitigate such situations. Lastly, equations were proposed to predict the lateral resistance of the test specimens.
12
Content available remote An experimental and numerical study of aluminium–concrete joints and composite beams
Polus Łukasz, Szumigała Maciej
Archives of Civil and Mechanical Engineering
|
2019
|
Vol. 19, no. 2
375--390
EN
The present study investigated the structural behaviour of aluminium–concrete composite (ACC) beams with profiled sheeting by means of conducting four-point bending tests on four ACC beams. In the proposed ACC system, a concrete slab was connected to aluminium girders by mechanical shear connectors developed by the authors of this article. The load-slip behaviour of the connections was characterised in push-out tests of connectors. In addition, non-linear 3D finite element (FE) models of the tested joints and composite beams were developed and verified against the experimental results. The comparison between the experimental and numerical results indicates that the adopted 3D model can capture the response of the ACC joints and composite beams fairly well.
13
Historia opracowania i wdrożenia połączenia ścinanego typu composite dowels. Część II - poziom elementu zespolonego
Lorenc W.
Mosty
|
2018
|
nr 6
70--74
PL
Połączenie composite dowels umożliwia tworzenie nowego rodzaju konstrukcji zespolonych. Po około 10 latach opracowywane są przepisy projektowe na poziomie europejskim. Artykuł jest kontynuacją materiału opublikowanego w wydaniu 5/2018 „Mostów” (str. 40-44).
EN
The connection with composite dowels enables creating a new type of composite structures. After approximately 10 years of implementations, the design regulations at the European level are being developed. The article is a continuation of the paper published in the 5/2018 issue of “Mosty” (pp. 40-44).
14
Historia opracowania i wdrożenia połączenia ścinanego typu composite dowels. Cz.ęść I – poziom połączenia ścinanego i poziom przekroju poprzecznego
Lorenc W.
Mosty
|
2018
|
nr 5
40--44
PL
Połączenie composite dowels umożliwia tworzenie nowego rodzaju konstrukcji zespolonych. Po około 10 latach wdrożeń opracowywane są przepisy projektowe na poziomie europejskim. W artykule przedstawiono, jak przebiegały prace, które doprowadziły do wdrożeń i powstania przepisów projektowania.
EN
The connection with composite dowels enables creating a new type of composite structures. After approximately 10 years of implementations, the design regulations at the European level are being developed. The article presents the efforts which have led to the implementation and development of design regulations.
15
Content available Evaluation of Impact Damage in Composite Structures Using Ultrasonic Testing
Wronkowicz-Katunin A., Dragan K.
Fatigue of Aircraft Structures
|
2018
|
Iss. 10
82--92
EN
Barely visible impact damage is one of the problems commonly occurring in composite elements during an aircraft operation. The authors described the mechanisms of impact damage formation and propagation in composite structures. The paper presents a performed analysis of an influence of impact parameters on the resulting damage, i.e. its detectability by means of visual observation as well as its extent determined based on ultrasonic tests results. The tests were conducted on the CFRP specimens with a wide range of impact damage cases obtained with combinations of variable impact energy and shapes of impactors. Additionally, an algorithm based on image processing and image analysis methods is proposed for the purpose of the effective evaluation of the ultrasonic data obtained.
16
Content available A Brief Review on NDT&E Methods For Structural Aircraft Components
Wronkowicz-Katunin A.
Fatigue of Aircraft Structures
|
2018
|
Iss. 10
73--81
EN
The paper presents a summary of non-destructive testing and evaluation (NDT&E) methods applied in inspections of structural aircraft components. This brief review covers the most commonly applied methods such as visual and penetrant inspections, tap-testing, eddy current inspections, shearography, thermography, acoustic emission testing, radiographic and tomographic inspections, and ultrasonic inspections. The general operating principles of these methods as well as their main advantages, limitations and application areas are described below.
17
Content available remote Laboratory tests of new connectors for timber-concrete composite structures
Szumigała M., Polus Ł., Szumigała E.
Engineering Transactions
|
2018
|
Vol. 66, iss. 2
161--173
EN
This paper presents the results of the laboratory tests of new connectors for timber-concrete composite (TCC) structures. These connectors can be used to join a timber beam with a concrete slab. They consist of two parts – a headed stud and a steel screw. The objective of our analysis was to examine the stiffness and strength of the connection, which can be used in designing TCC beams. The authors introduced formulas for calculating the above mentioned parameters. The results obtained in the experimental tests are compared with those calculated using the proposed formulas.
18
Content available Stability Problems of Compressed Thin-Walled Structures
Dębski Hubert
Advances in Science and Technology. Research Journal
|
2018
|
Vol. 12, no 4
190--198
EN
The object of this study involves thin-walled columns made of carbon-epoxy composite with open top-hat cross-section. The material used comprised a composite of epoxy matrix reinforced with carbon fiber (system HexPly M12, Hexcel). The M12 system is used above all in aircraft structures. It exhibits high fatigue durability and good maintenance properties at relatively low specific gravity. The research was carried out as the FEM numerical analyses and experimental tests in buckling and post-buckling state. The numerical tool used was the ABAQUS software.
19
Damage evaluation in composite structures based on image processing of ultrasonic c-scans
Wronkowicz A., Katunin A.
Studia Informatica
|
2017
|
Vol. 38, nr 1B
31--40
EN
The article presents a method of reconstruction of planar ultrasonic maps into a three-dimensional form based on levels of attenuation of ultrasonic waves through a tested composite structure. A developed algorithm is based on image processing techniques, which allows enhancing ability of interpretation of damage extent at particular depths of a tested structure.
PL
Artykuł przedstawia metodę rekonstrukcji płaskich map ultradźwiękowych do postaci trójwymiarowej na podstawie poziomów tłumienia fal ultradźwiękowych przez badaną strukturę kompozytową. Opracowany algorytm został oparty na technikach przetwarzania obrazu, które pozwalają na wspomaganie interpretacji rozległości uszkodzeń na poszczególnych poziomach głębokości w badanej strukturze.
20
Detection of damage initiation in composite structures subjected to self-heating based on acoustic emission
Wronkowicz A., Katunin A.
Modelowanie Inżynierskie
|
2017
|
T. 33, nr 64
114--119
EN
Structural integrity is one of the crucial properties of designed composite elements. However, during their operation they are subjected to various types of loading, and thus, subjected to degradation. Intensity of their degradation is driven by many factors with different degree of influence. One of such degradation mechanisms occurs during cyclic loading, when heat is released on the surface of a polymeric composite structures due to the mechanical energy dissipation, which has a great influence on degradation acceleration. The paper deals with determination of a criticality of the self-heating effect, i.e. temperature value at which damage initiation occurs during cyclic loading of composite structures. For this purpose, polymeric composite specimens were subjected to fatigue tests and resulting surface temperature and acoustic emission were measured and analyzed. The obtained results indicated that analysis of acoustic emission features enables returning information about the two critical moments of the degradation process. From a linear peak amplitude one can assess a critical moment between the two first phases of the three-phase degradation model, when propagation of micro-cracks and initiation of a macrocrack occurs. Analysis of the amplitude, together with the energy ratio and the total energy of hit-cascade, can also accurately indicate a moment of transition from the second to the third phase, when a macro-crack propagates rapidly, which finally results in a failure of the structure.
PL
Integralność strukturalna jest jedną z kluczowych właściwości projektowanych elementów kompozytowych. Jednak podczas eksploatacji są one narażone na różnego rodzaju obciążenia i dlatego ulegają degradacji. Intensywność ich degradacji jest uwarunkowana przez wiele czynników z różnym poziomem istotności. Jeden z takich mechanizmów degradacji występuje podczas obciążenia cyklicznego, gdy ciepło jest uwalniane na powierzchni polimerowej struktury kompozytowej ze względu na dyssypację energii mechanicznej, co ma istotny wpływ na przyspieszenie degradacji. W artykule omówiony został proces określenia krytyczności efektu samorozgrzania, tj. wartości temperatury przy której następuje inicjacja uszkodzeń w strukturach kompozytowych. W tym celu próbki wykonane z kompozytu polimerowego zostały poddane badaniom zmęczeniowym oraz ich wynikowa temperatura powierzchni oraz emisja akustyczna została zmierzona i przeanalizowana. Otrzymane wyniki wykazały, że cechy uzyskane w oparciu o emisję akustyczną pozwalają na pozyskanie informacji o dwóch krytycznych momentach procesu degradacji. Na podstawie liniowej amplitudy szczytowej można określić krytyczny moment pomiędzy dwiema pierwszymi fazami w trójfazowym modelu degradacji, gdy następuje propagacja mikropęknięć i inicjacja makropęknięcia. Analiza amplitudy razem z wartościami energii oraz całkowitą energią kaskady impulsów pozawala także dokładnie wskazać moment przejścia z drugiej do trzeciej fazy, gdzie makropęknięcie szybko propaguje, co ostatecznie doprowadza do zniszczenia struktury.
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