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  1. 12 Inżynieria i Budownictwo
  2. 11 Materiały Budowlane
  3. 8 Archives of Civil and Mechanical Engineering
  4. 7 International Journal of Applied Mechanics and Engineering
  5. 6 Modelling in Engineering
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  1. 3 Jankowiak R.
  2. 3 Kaleta B.
  3. 3 Kamiński M.
  4. 3 Mielczarek Z.
  5. 3 Musiał M.
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  1. 5 2023
  2. 3 2022
  3. 2 2021
  4. 6 2020
  5. 4 2019
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1
Uwiarygodnienie koncepcji „projektowania plastycznego” belek mostowych zgodnie z Eurokodem 4: Badania niszczące w skali naturalnej zespolonych belek mostowych złożonych z dwuteownika HL1100 i płyty betonowej
Marcinczak Krzysztof, Kożuch Maciej, Lorenc Wojciech, Zannon Riccardo, Ochojski Wojciech
Mosty
|
2023
|
nr 3
47-50
PL
W artykule przedstawiono wyniki eksperymentów niszczących, które rzucają nowe światło na projektowanie mostów zespolonych w Polsce. Różnica między tradycyjnymi normami a nowoczesnym podejściem opartym na Eurokodzie 4 jest widoczna. Wyniki badań opisane przez autorów stanowią solidny argument za zmianą tradycyjnych praktyk.
EN
The article presents the results of destructive experiments, which shed new light on the design of composite bridges in Poland. The difference between traditional norms and a modern approach based on Eurocode 4 is evident. The test findings described by the authors provide a strong argument for changing traditional practices.
2
Content available remote Wykorzystanie zdolności pochłaniania energii do wyznaczania wytrzymałości resztkowych fibrokompozytów
Głodkowska Wiesława, Laskowska-Bury Joanna, Lehmann Marek
Materiały Budowlane
|
2023
|
nr 3
1--4
PL
W artykule omówiono sposób wyznaczania wytrzymałości resztkowych z wykorzystaniem zdolności pochłaniania energii przez fibrokompozyt. Badania przeprowadzono przez zginanie płyt o przekroju kwadratowym podpartych przegubowo na obwodzie. Określone w ten sposób wytrzymałości resztkowe cechują się znacznie mniejszym współczynnikiem zmienności niż wyznaczone wg PN-EN 14651:2007. Opisane badanie jest alternatywą dla 3-punktowego zginania belek i pozwala na wyznaczenie tej cechy z większą wiarygodnością.
EN
The article discusses the method of determining residual strength using the energy absorption capacity of fibrecomposite. The research was carried out by bending square cross-section plates simply supported at the perimeter. The residual strengths determined in this way are characterized by a much lower coefficient of variation than those determined using the normative method according to PN-EN 14651:2007. The described test is an alternative to 3-point bending of beams and allows to determine this feature with greater reliability.
3
Content available A posteriori error estimates for beams with inexact flexural stiffness representation
Torii André J., Gracite Paula M.A., Miguel Leandro F.F., Lopez Rafael H.
Journal of Applied Mathematics and Computational Mechanics
|
2023
|
Vol. 22, nr 2
62--74
EN
In this work, we present a posteriori error estimates for the Euler-Bernoulli beam theory with inexact flexural stiffness representation. This is an important subject in practice because beams with non-uniform flexural stiffness are frequently modeled using a mesh of elements with constant stiffness. The error estimates obtained in this work are validated by means of two numerical examples. The estimates presented here can be employed for adaptive mesh refinement.
4
Content available Influence of material distribution and damping on the dynamic stability of Bernoulli-Euler beams
Garus Sebastian, Garus Justyna, Sochacki Wojciech, Nabiałek Marcin, Petru Jana, Borek Wojciech, Šofer Michal, Kwiatoń Paweł
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2023
|
Vol. 71, nr 4
art. no. e145567
EN
The study analyzed the influence of materials and different types of damping on the dynamic stability of the Bernoulli-Euler beam. Using the mode summation method and applying an orthogonal condition of eigenfunctions and describing the analyzed system with the Mathieu equation, the problem of dynamic stability was solved. By examining the influence of internal and external damping and damping in the beam supports, their influence on the regions of stability and instability of the solution to the Mathieu equation was determined.
5
Content available remote Numerical failure analysis of laminated beams using a refined finite element model
Layachi Maroua, Khechai Abdelhak, Ghrieb Abderrahmane, Layachi Safa
Advances in Materials Science
|
2023
|
Vol. 23, nr 1(75)
32--57
EN
In the present investigation, laminated composite beams subjected to a bending static loading are studied in order to determine their failure mechanisms and the first ply failure (FPF) load. The FPF analysis is performed using a refined rectangular plate element. The present element is formulated based on the classical lamination theory (CLT) to calculate the in-plane stresses. To achieve this goal, several failure criterions, including Tsai-Wu, Tsai-Hill, Hashin, and Maximum Stress criteria, are used to predict failure mechanisms. These criterions are implemented within the finite element code to predict the different failure damages and responses of laminated beams from the initial loading to the final failure. The numerical results obtained using the present element compare favorably with those given by the analytic approaches. It is observed that the numerical results are very close to the analytical results, which demonstrates the accuracy of the present element. Finally, several parameters, such as fiber orientations, stacking sequences, and boundary conditions, are considered to determine and understand their effects on the strength of these laminated beams.
6
Content available Influence of the PZT actuator asymmetry on the LQR control parameters in the active reduction vibrations of beams
Kuras Romuald
Vibrations in Physical Systems
|
2022
|
Vol. 33, nr 3
art. no. 2022305
EN
The paper deals with the active reduction of beam vibrations using piezoelectric transducers (PZT). The LQR parameters of the control of an asymmetric actuator (a-PZT) depending on the length of its arms were analysed. The results were compared to those of the symmetrical PZT (s-PZT), so far used as standard. The actuator is modeled with two bending moments or two pairs of forces. The design of the LQR controller also took into account the location of the PZT on the beam. The reduction efficiency can also be increased by using asymmetrical PZT. To obtain the vibration asymmetry of the beam, simply supported at both ends, an asymmetrically point mass was added. The LQR control was applied to an asymmetric actuator on the beam. Two-parameter optimization was used to find the optimal proportions of the a-PZT arms. For such a problem, the LQR control parameters were found, which ensure the highest efficiency of vibration reduction.
7
Content available Analysis of deflection in visco-thermoelastic beam resonators subjected to harmonic loading
Chopra Deepti, Singh Prince
International Journal of Applied Mechanics and Engineering
|
2022
|
Vol. 27, no. 2
35--52
EN
This paper analyses the transverse deflection in a homogeneous, isotropic, visco-thermoelastic beam when subjected to harmonic load. The ends of the beam are considered at different boundary conditions (both axial ends clamped, both axial ends simply supported and left end clamped and right end free). The deflection has been studied by using the Laplace transform. Numerical computation of analytical expression of deflection obtained after Inverse Laplace transform has been done using MATLAB software. The graphical observations have been discussed under various boundary conditions for different values of time and length. The above work has applications in design of resonators.
8
Content available A method for comparison of large deflection in beams
Taghipour Yasser, Darfarin Sara
International Journal of Applied Mechanics and Engineering
|
2022
|
Vol. 27, no. 4
179--193
EN
The deflection analysis of beams has been recently an active area of research. The large deflection of beams refers to deflections occurring due to large displacements and small strains. This type of deflection has been one of the areas of interest in the development of beam deformation methods. The wide diversity of beam deformation methods highlights the importance of their comparison to further elucidate the properties and features of each method and determine their benefits and limitations. In this study, a new comparison model is introduced which involves three steps, instead of only comparing final results for verification in common studies. In the first step, a complete comparison is made based on the assumptions and approximations of each method of the kinematics of deformation, displacement, and strain fields. After selecting the most accurate method in the first step, the displacement functions are determined by polynomial approximation under different loading and support conditions based on the selected method. In the third step, the displacement functions are used to calculate the strains in each method. The conclusion is based on comparing the strains. This comparative model can be used as a benchmark to compare different theories of deformation analysis.
9
Porównanie wybranych metod oceny momentu krytycznego zwichrzenia belek o zmiennej wysokości środnika
Czepiżak Dariusz, Machowiak Adam
Inżynieria i Budownictwo
|
2021
|
R. 77, nr 5-6
269--274
PL
Porównano sprężyste momenty krytyczne belek ze zbieżnym środnikiem, obliczone metodami analitycznymi i numerycznymi przedstawionymi w ostatnich latach przez badaczy zajmujących się tym zagadnieniem z obliczeniami własnymi, przeprowadzonymi dostępnymi narzędziami. Głównym celem było zweryfikowanie dokładności i zbieżności wyników otrzymanych różnymi metodami i różnymi prętowymi elementami skończonymi 1D o 7 stopniach swobody w węźle (7DOF).
EN
In this article, the elastic critical bending moments of the web-tapered I-beams calculated by the analytical and numerical solutions developed last years by researchers involved in the topic were compared with own calculations carried out with available common tools. The main goal was to verify the accuracy and convergence of the results provided by different modern methods and different finite bar elements 1D with 7 degrees od freedom at the node (7DOF).
10
Content available A new index for damage identification in beam structures based on modal parameters
Taghipour Reza, Nashta Mina Roodgar, Bozorgnasab Moshen, Mirgolbabaei Hessam
Archive of Mechanical Engineering
|
2021
|
LXVIII, nr 4
375--394
EN
The structural damages can lead to structural failure if they are not identified at early stages. Different methods for detecting and locating the damages in structures have been always appealing to designers in the field. Due to direct relation between the stiffness, natural frequency, and mode shapes in the structure, the modal parameters could be used for the purpose of detecting and locating the damages in structures. In the current study, a new damage indicator named “DLI” is proposed, using the mode shapes and their derivatives. A finite element model of a beam is used, and the numerical model is validated against experimental data. The proposed index is investigated for two beams with different support conditions and the results are compared with those of two well-known indices – MSEBI and CDF. To show the capability and accuracy of the proposed index, the damages with low severity at various locations of the structures containing the elements near the supports were investigated. The results under noisy conditions are investigated by considering 3% and 5% noise on modal data. The results show a high level of accuracy of the proposed index for identifying the location of the damaged elements in beams.
11
Content available The impact of the agressive acid environment on RC constructions
Blikharskyy Yaroslav, Khmil Roman, Blikharskyy Zinoviy, Shnal Taras
System Safety : Human - Technical Facility - Environment
|
2020
|
Vol. 2, nr 1
223--229
EN
The main issue of the article is the corrosion of the reinforced concrete elements by the co-influence of the aggressive and power factors. The problem of corrosion is extremely actual one. Therefore the tests were carried out upon the specimens considering the corrosion in the acid environment, namely 10 % H2SO4. The acid environment H2SO4 was taken as a model of the aggressive environment. Conclusions concerning the corrosion model of the cross section and investigation of stress-strain state have been made. That material concerns the problem of the reinforced concrete corrosion as a whole construction. Reinforced concrete beams were tested with and without the co-action of the aggressive environment and power factor.
12
Content available Wykrywanie uszkodzeń w konstrukcjach inżynierskich przy zastosowaniu metody dyskretnej transformacji falkowej
Knitter-Piątkowska Anna, Guminiak Michał
Przegląd Budowlany
|
2020
|
R. 91, nr 11
61--64
PL
Badania związane z wykrywaniem uszkodzeń i osłabień elementów konstrukcyjnych stanową bardzo ważny element kompleksowej analizy budowli inżynierskich. W analizie identyfikacji uszkodzeń wiodącą rolę odgrywają tzw. metody nieniszczące, które pozwalają dostatecznie precyzyjnie zlokalizować powstałe uszkodzenia. Prezentowana praca poświęcona jest zastosowaniu dyskretnej transformacji falkowej w procesie lokalizacji uszkodzeń konstrukcji. Dowolne uszkodzenie, np. w postaci lokalnego osłabienia sztywności konstrukcji (pęknięcia), jest przyczyną zaburzenia w rejestrowanym sygnale odpowiedzi - ugięciu, deformacji przekroju lub np. przyspieszeniu wybranego punktu konstrukcji. Zaburzenie sygnału jest na tyle małe, że dopiero jego przetworzenie za pomocą analizy falkowej pozwala zlokalizować miejsce uszkodzenia. Zaletą przedstawionej procedury jest wykorzystanie wyłącznie sygnału odpowiedzi rzeczywistej konstrukcji uszkodzonej. Przedstawiono krótki przegląd dotychczasowych analiz konstrukcji płytowych (płyt cienkich).
EN
Research related to the detection of damage and weakening of structural elements is a very important element of a comprehensive analysis of engineering structures. In the analysis of damage identification, the leading role is played by the so-called non-destructive methods that allow for sufficiently precise localization of the damage. The presented work is devoted to the application of the discrete wavelet transformation (DWT) to the process of identification and localization damages in structures. Any damage, e.g. in the form of a local weakening of the structure stiffness (cracks), causes disturbances in the recorded response signal - deflection, deformation of the cross-section or e.g. acceleration of a selected point of the structure. However, the signal disturbance is so small that only its processing by means of wavelet analysis allows to locate the damage site. The advantage of the presented procedure is the use of the response signal only of the real - damaged structure. The presented work is an overview of the results obtained so far. The slabs were analyzed as the basic surface structural systems that form the building structure.
13
Content available remote Wybrane aspekty technologii strunobetonu na przykładzie sprężonych belek i dźwigarów stosowanych w konstrukcjach hal
Nicał Aleksander
Nowoczesne Hale
|
2020
|
Nr 4
25--29
PL
W artykule przedstawiono wybrane zagadnienia dotyczące produkcji belek i dźwigarów strunobetonowych. Elementy te stanowią szeroką grupę prefabrykatów budowlanych stosowanych przy budowie wielkopowierzchniowych hal. Artykuł opisuje m.in. genezę technologii konstrukcji sprężonych, w tym chronologiczny wykaz najważniejszych osiągnięć w zakresie technologii strunobetonu. Dodatkowo opisane zostały podstawowe charakterystyki strunobetonu oraz dokonano przeglądu wybranych belek i dźwigarów strunobetonowych na polskim rynku. Artykuł zawiera również podstawowe wymagania w zakresie betonu i stali stosowanych w konstrukcjach strunobetonowych oraz opis metod produkcji belek i dźwigarów strunobetonowych. Opisane zostały również straty przy naciągu zbrojenia belek i dźwigarów strunobetonowych.
EN
The article presents selected issues concer­ning the production of prestressed concrete beams and girders. These elements constitute a wide group of building prefabricates used in the construction of large area halls. The article presents, among others, the genesis of prestressed concrete elements technology, including a chronological list of the most important achievements in prestressed concrete technology. Moreover, the basic characteristics of prestressed concrete are described and selected beams and girders available on the Polish market are reviewed. The article also includes the basic requirements for concrete and steel used in prestressed concrete structures and a description of the production methods of prestressed concrete beams and girders. Finally, losses in the tension of the reinforcement of prestressed concrete beams and girders are described.
14
Content available Hybrid sandwich panels: a review
Sandeep S. H., Srinivasa C. V.
International Journal of Applied Mechanics and Engineering
|
2020
|
Vol. 25, no. 3
64--85
EN
A high specific stiffness, high specific strength, and tailoring the properties for specific application hale attracted the attention of the researchers to work in the field of laminated composites and Sandwich structures. Rapid use of these laminated composites and Sandwich structures necessitated the development of new theories that suitable for the bending, buckling and vibration analysis. Many articles were published on free vibration of beams, plates, shells laminated composites and sandwich structures. In this article, a review on free vibration analysis of shear deformable isotropic beams, plates, shells, laminated composites and sandwich structures based on various theories and the exact solution is presented. In addition to this, the literature on finite element modeling of beams, plates, shells laminated composites and sandwich structures based on classical and refined theories is also reviewed. The present article is an attempt to review the available literature, made in the past few decades on free flexural vibration response of Fiber Metal laminated Composites and Sandwich panels using different analytical models, numerical techniques, and experimental methods.
15
Content available remote Primal- and dual-mixed finite element models for geometrically nonlinear shear-deformable beams – a comparative study
Bertóti Edgár
Computer Assisted Methods in Engineering and Science
|
2020
|
Vol. 27, no. 4
285--215
EN
The relationships between the system matrices of the displacement-based, a primal-mixed, a dual-mixed and a consistent primal-dual mixed finite element model for geometrically nonlinear shear-deformable beams are investigated. Employing Galerkin-type weak formulations with the lowest possible order, constant and linear, polynomial approximations, the tangent stiffness matrices and the load vectors of the elements are derived and compared to each other in their explicit forms. The main difference between the standard and the dual-mixed element can be characterized by a geometry-, material- and meshdependent constant that can serve not only as a locking indicator but also to transform the displacement-based element into a shear-locking-free dual-mixed beam element. The numerical performances of the four different elements are compared to each other through two simple model problems. The superior performance of the mixed, and especially the dual-mixed, beam elements in the nonlinear case is demonstrated, not only for the deflection, but also for the force and moment computations.
16
Content available remote Cyclic behavior of strong beam–weak column joints strengthened with different configurations of CFRP sheets
Ilia Elaheh, Mostofinejad Davood, Moghaddas Amirreza
Archives of Civil and Mechanical Engineering
|
2020
|
Vol. 20, no. 2
1--26
EN
The current paper reports the results of experiments on deficient exterior reinforced concrete (RC) strong beam–weak column connections strengthened with carbon fiber-reinforced polymer (CFRP) sheets. Five RC-joint specimens with half-scale size were manufactured and tested subjected to constant axial and reversed cyclic quasi-static loads. These joints consisted of one control and four specimens retrofitted with FRP sheets used in different strengthening configuration. The study is mainly directed to the examination of the different anchoring methods for longitudinal FRPs at beam–column intersection including L-shaped anchorage or CFRP anchor fans as a modern anchorage technique. Furthermore, the efficiency of transverse CFRP sheets in the form of innovative corner strip-batten technique to improve the seismic performance of the weak column was compared with longitudinal sheets. The externally bonded reinforcement on grooves (EBROG) method was also used in all strengthening schemes to eliminate surface debonding of CFRP. Test results revealed that although all the retrofitting schemes used led to significant improvements of up to 80% in strength capacity, longitudinal FRP sheets applied through the EBROG method and anchored with CFRP fans were more effective in inducing a completely ductile behavior in the joints, while the plastic hinge was also relocated into the beam.
17
Content available remote Finite element analysis of reinforced concrete elements subjected to torsion
Anielska Dorota
Technical Transactions
|
2019
|
Vol. 116, iss. 2
129--139
EN
This paper presents FEM techniques used for modelling concrete elements subjected to torsion. It compares the results from a 3D numerical analysis and a numerical homogenization method analysis. Finally, the results are compared to the reported experimental data.
PL
W artykule przedstawiono sposoby modelowania skręcanych elementów żelbetowych za pomocą Metody Elementów Skończonych. Zaprezentowano porównanie wyników otrzymanych w trójwymiarowej analizie numerycznej oraz w analizie numerycznej bazującej na teorii homogenizacji. Wyniki zestawiono z wynikami eksperymentalnymi znanymi z literatury.
18
Content available Stress state in the tapered beam bending : analytical and numerical FEM studies
Magnucki Krzysztof, Lewiński Jerzy, Stawecka Hanna
Pojazdy Szynowe
|
2019
|
Nr 2
1--8
EN
The paper is devoted to comparative analysis of the stress state in bending of a tapered cantilever beam, calculated analytically and numerically (FEM). The analytical model is described based on bibliography, moreover, the numerical FEM model is developed with the use of the SolidWorks software. The results i.e. the stresses obtained by analytical and numerical calculation are compared and specified in Tables and Figures.
PL
Praca przestawia analizę porównawczą stanu naprężenia w zginanej belce wspornikowej o zmiennej wysokości. Przeprowadzono obliczenia analityczne i numeryczne metodąelementów skończonych. Model analityczny został opisany na podstawie literatury, na-tomiast model do obliczeń metodą elementów skończonych opracowano z zastosowaniem systemu SolidWorks. Wyniki, tzn. naprężenia wyznaczone analitycznie i numerycznie zostały porównane i zamieszczone w tablicach oraz zilustrowane na rysunkach.
19
Content available Metoda DIC
Marcinczak Dorota
Builder
|
2019
|
R.23, nr 2
66--68
EN
The article presents tests of a reinforced concrete beam strengthened in a shear with PBO-FRCM composite materials. Measurement of the deformation of the composite was carried out using two methods - with strain gauges and the optical DIC method (Digital Image Correlation). The DIC method consists in taking a series of photographs of the tested object before and during loading. The surface of the tested element must have randomly spaced spots that are applied to the object before measurement. During the study, the cameras monitor the shifting of spots against each other, which in comparison to the reference image before loading gives information about strains and stresses of the tested element. Measurements of deformation of composite materials using strain gauges are difficult to clearly analyze, because the strain gauge is in a specific, limited place, which does not correspond to the work of the entire composite. In addition, the strain gauge tends to break at the place of crack. The article discusses this problem by presenting the results of deformation of PBO-FRCM composite meshes measured in two mentioned ways, their comparison and discussion of results.
20
Content available remote Experimental study on the shear strength of reinforced concrete beams cast with Lava lightweight aggregates
Nawaz W., Abdalla J. A., Hawileh R. A., Alajmani H. S., Abuzayed I. H., Ataya H., Mohamed H. A.
Archives of Civil and Mechanical Engineering
|
2019
|
Vol. 19, no. 4
981--996
EN
This paper investigates experimentally the shear strength behavior of reinforced concrete (RC) beams cast with Lava lightweight aggregates as a replacement of normal coarse aggregates. A total of 24 shear deficient RC beams were fabricated and cast with normal (NWC) and lightweight (LWC) concrete and tested under three-point bending after 28 and 56 days. The variables of the experimental program include type of aggregate, concrete compressive strength, and beam size. The experimental results include load–deflection response curves along with failure mode for each beam specimen. The experimental result showed that all beams failed in a similar fashion, due to diagonal tension shear crack. However, a larger number of cracks with less spacing occurred in the LWC beams as compared to NWC specimens. Based on the experimental results, it can be also concluded that LWC specimens tested after 56 days achieved comparable shear strength results to that of NWC beams. In addition, the strength reduction factor (l) for LWC specimens was in the range of 0.69–0.98. The concrete shear strength (Vc) was also predicted using different shear design provisions and the results has shown that Eurocode 2 provisions yielded the lowest C. O.V. of 2.3 and 10.2% for NWC and LWC specimens, respectively.
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