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1

Structural Response of Beam-Column Joint Made of Fiber Reinforced Concrete (FRC) Using ANSYS FEA Simulation

Verma Isha, Gautam Lalit, Gomkale Shruti, Goyal Anuj, Berwal Parveen, Asmari Abdullah Faiz Al, Islam Saiful

Rocznik Ochrona Środowiska

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2025

|

Tom 27

174--195

EN

Beam-column joints are crucial in reinforced concrete and steel structures, which transfer load from beams to columns and vice versa. They are essential to withstand various types of loads, such as lateral, gravity, and seismic loads. The material of the beam-column joint determines the joint's ability to withstand and transfer loads between beams and columns. The stronger material would enhance its strength and overall load-bearing capacity and vice versa. Current research aims to evaluate the structural response of beam-column joints made of Fiber Reinforced Concrete (FRC's) using ANSYS FEA simulation package. The effect of fiber concentration, i.e., 0.3%, 0.6%, and 0.9%, on the strength of the beam-column joint is evaluated based on structural evaluation parameters. The other objective is to evaluate the effect of graphene fiber (the aspect ratio is 1:1, although up to 1.5 is typically acceptable) on improving the strength of the beam-column joint. Comparative studies are conducted, and materials are evaluated based on stiffness, ductility and energy dissipation. The graphene-reinforced concrete demonstrates less stiffness degradation with increased strain. This indicates that the incorporation of graphene improves the stiffness retention capacity of the concrete. The hysteresis loop of graphene-reinforced concrete is broader, signifying enhanced ductility. This indicates that the material can sustain greater deformations without failure, essential for seismic performance. The 0% FRC has minimal ductility, characterized by a notable reduction in stress upon first loading. The 0.3% and 0.6% FRC show improved ductility, with higher stress levels maintained over larger strains. The 0.9% FRC demonstrates the highest ductility, maintaining higher stress over the full strain range, indicating it can undergo larger deformations without failure. The stiffness degradation is less pronounced in higher FRC concentrations.

2

Bending behaviour of thin-walled perforated channel beams with modified cross-sectional shape – Part 1: experimental tests and FSM

Paczos Piotr, Pawlak Aleksandra M., Jasion Paweł, Plust Michał

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

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Vol. 73, nr 3

art. no. e153830

EN

The subject of this study is thin-walled channel sections with a modified cross-sectional shape. The investigation involved six beams, three of which had perforations on the web, while the other three had a flat, solid web. The beams were subjected to four-point bending tests. Experimental tests were conducted using both electronic and optical methods, with a test setup specifically designed for this investigation. Additionally, numerical analyses were performed using the finite strip method. The primary objective of the research was to determine the impact of web perforations on the strength and stability of the bent beams. The perforation of the web also resulted in a reduction in the overall weight of the structure, thereby decreasing material consumption. Based on the research, the critical forces and maximum forces at which total loss of load-bearing capacity occurred were determined. Furthermore, the buckling modes of the beams were identified. The study revealed that the critical and maximum forces for beams with perforated webs were lower compared to beams with a flat, solid web. However, the significant reduction in weight for the perforated beams suggests that their use remains advantageous. The results of FEM and analytical analyses, essential for modelling and understanding complex behaviours in thin-walled structures, will be presented in the second part of this publication to maintain clarity and accessibility.

3

The Impact of Longitudinal and Stirrups Reinforcement Ratio to Shear Strength Capacity of Geopolymer Concrete Beam

Tajunnisa Yuyun, Apsari Auliagitta K., Bayuaji Ridho, Mansur Moh. Safi'i

Archives of Metallurgy and Materials

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2025

|

Vol. 70, iss. 1

341--350

EN

The shear capacity of reinforced beam concrete was designed to resist the stirrup reinforcement, Vs, and by the concrete itself, Vc. Previous studies of geopolymer concrete show the mechanical properties of this proposed green concrete, yet the structural investigation is infrequently investigated. These studies mostly observed the impact of using alternative binder resources that affect the workability, setting time, compressive strength, split tensile strength, and drying shrinkage. Therefore, this study aims to observe the structural behavior of geopolymer concrete, precisely its shear capacity. Four geopolymer concrete beam types were designed to have shear failure mode when tested using a Universal Testing Machine by four-point load bending method. The results showed that geopolymer concrete has ductile behavior. Comparison between the Vu value of the test results with Vn calculation of nominal cross-sectional capacity according to standard concrete rules in an average of 2.11 higher than the nominal capacity conventionally calculated according to SNI. Two models of linear regression equations for concrete Vc values were created to explore this further. It was found that the presence of a constant increases the value of the coefficient of determination by up to 29% for the Vc equation in geopolymer concrete. In addition, cracking patterns observed with the DIC method using GOM Correlate software also showed that all the beam specimens had failure both in flexure and shear, even though they all are designed in a shear failure state.

4

Retrofitting fiber-reinforced concrete beams with nano-graphene oxide and CFRP sheet: an experimental study

Halvaeyfar Mohammad Reza, Azandariani Mojtaba Gorji, Zeighami Ehsanollah, Mirhosseini S. Mohammad

Archives of Civil and Mechanical Engineering

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2025

|

Vol. 25, no. 1

art. no. e32, 2025

EN

This experimental study investigates the effectiveness of retrofitting fiber-reinforced concrete (FRC) beams using nano-graphene oxide (GO) and carbon fiber-reinforced polymer (CFRP) sheets. The primary goal is to evaluate the combined effect of GO and CFRP sheets on the mechanical performance of FRC beams. The experimental program involved preparing and testing multiple concrete beam specimens, with some retrofitted using GO and CFRP sheets. The principal results indicate that the integration of GO significantly enhances the compressive and tensile strength of concrete. Additionally, the application of CFRP sheets markedly improves the flexural strength and ductility of the beams. The retrofitted specimens exhibited higher load-bearing capacity and greater deformation before failure compared to control specimens. The significant conclusions drawn from this study are that the combined use of GO and CFRP sheets provides a synergistic effect, improving the overall mechanical performance of FRC beams. However, failure modes such as debonding and delamination of CFRP sheets highlight the need for optimization in bonding techniques and materials. The primary research outcomes demonstrate that retrofitting FRC beams with GO and CFRP sheets is a promising approach for enhancing the structural performance. This study underscores the potential of advanced materials in structural retrofitting and provides insights for future research to address observed failure modes and further improve the retrofitting techniques.

5

Assessment of reinforced concrete beams cracking depending on the concrete class

Derlatka Anna, Jrethi Yassin Ali

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2024

|

Z. 30 (180)

29--34

EN

Cracks in reinforced concrete are a common concern that can arise from various causes such as concrete shrinkage, temperature differences, and structural loads. The aim of the study was an analysis of cracks in concrete on which the reinforcement concrete beam was made. The beam was loaded with an evenly distributed load and subjected to bending. Depending on the concrete class (C20/25, C25/30 and C30/37), the cracks in the concrete, the deflection at a load of 5.35 kN/m2 and the beam’s load-bearing capacity, i.e. the value of the load that the beam can withstand without any cracks were assessed.

PL

Pęknięcia w żelbecie są powszechnym problemem, który może wynikać z różnych przyczyn, takich jak skurcz betonu, różnice temperatur i obciążenia konstrukcyjne. Celem pracy była analiza pęknięć w betonie, z którego wykonano belkę żelbetową. Belka została obciążona równomiernie rozłożonym obciążeniem i poddana zginaniu. Analizowano trzy klasy betonu C20/25, C25/30 i C30/37. W zależności od klasy betonu oceniano pęknięcia w betonie, ugięcie przy obciążeniu 5.35 kN/m2 i nośność belki, tj. wartość obciążenia, jakie belka może wytrzymać bez pęknięć.

6

Modeling and control of a combined inverted pendulum on beam system

Choukri Bensalah, Amal Choukchou Braham, Rida Mokhtari

Przegląd Elektrotechniczny

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2024

|

R. 100, nr 9

213--218

EN

This paper addresses a novel structure for an underactuated system. It involves the combination of two well-known underactuated systems: the inverted pendulum-cart and the ball and beam. In this configuration, the cart in the first system replaces the role of the ball in the second. The primary focus lies in controlling the balancing beam, which is the key element of the system. The complete system is modeled using Lagrangian formulation, resulting in a set of coupled and highly nonlinear dynamical equations. Additionally, structural analysis of the corresponding control flow diagram is discussed. To control the entire system, an LQR controller with a PI controller in a cascade structure is employed. Simulation results demonstrate the stabilization performance of the proposed controller and its capability to address tracking problems.

PL

W artykule tym omówiono nową strukturę niedostatecznie aktywowanego układu. Obejmuje ona połączenie dwóch dobrze znanych niedostatecznie aktywowanych układów: odwróconego wózka wahadłowego oraz kuli i belki. W tej konfiguracji wózek w pierwszym układzie zastępuje rolę kuli w drugim. Główny nacisk położony jest na sterowanie belką równoważącą, która jest kluczowym elementem układu. Cały układ jest modelowany przy użyciu formuły Lagrange’a, co skutkuje zestawem sprzężonych i wysoce nieliniowych równań dynamicznych. Ponadto omówiono analizę strukturalną odpowiadającego schematu przepływu sterowania. Aby sterować całym układem, zastosowano regulator LQR z regulatorem PI w strukturze kaskadowej. Wyniki symulacji pokazują wydajność stabilizacji proponowanego regulatora i jego zdolność do rozwiązywania problemów ze śledzeniem.

7

Frequency-based crack effect study on beams under free vibration using finite element analysis

Sahu Ompriya, Das Priyadarshi, Muni Manoj Kumar, Pradhan Nibedita, Basa Bidyadhar, Sahu Shishir Kumar

Engineering Transactions

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2024

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Vol. 72, iss. 1

95--114

EN

A numerical computation-based analysis of the free vibration analysis of uniform beams with rectangular cross-sections is presented in this work using finite element analysis. The approach involves dividing the beam into segments at the crack section, which is then modelled for simulation for eigenfrequencies on the ABAQUS platform. The numerical simulation results are in excellent agreement with the findings of previous research, confirming the efficacy and applicability of the developed beam model. A sequential comprehensive approach towards analysis of the effects of the position and depth of the cracks on the natural frequencies are addressed in numerical results. The research findings confirm that the simulation model is suitable for the vibration analysis of beams or beam-like elements with different cross-sections.

8

Research into the bearing capacity of reinforced concrete bent elements strengthened by the FRCM system

Tereshko Andriy, Blikharskyy Yaroslav

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

|

2024

|

Vol. 13

246-252

EN

This article presents the experimental results of reinforced concrete beams strengthened by the FRCM system. To realize the set goal of the work, 4 reinforced concrete beams of real dimensions 2100 mm × 180 mm × 140 mm were manufactured. Exhaustion of the load-bearing capacity of all samples occurred due to the fluidity of the reinforcement. After the moment of reaching the flow of the reinforcement, physical destruction occurred in all samples due to the fragmentation of the compressed zone of concrete. Studies of reinforced samples showed that the non-shearing capacity was 16 % higher compared to non-reinforced control samples.

9

Dynamic Stability of the Periodic and Aperiodic Structures of the Bernoulli-Euler Beams

Garus Justyna, Petrů Jana, Sochacki Wojciech, Garus Sebastian

Archives of Metallurgy and Materials

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2024

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Vol. 69, iss. 1

275--279

EN

The study analyzed the influence of periodic and aperiodic stiffness distribution for the four-element Bernoulli-Euler beam on the first two eigenfrequencies and the dynamic stability of the system. The influence of increasing the ratio of cross-sections of the analyzed elements was also analyzed. Significant differences were found in eigenfrequencies and dynamic stability. Using the variational Hamilton principle, the equation of motion was derived, on the basis of which the values of the eigenfrequencies were determined, and the transformation into the form of the Mathieu equation made it possible to determine the dynamic stability for the analyzed structures.

10

An experimental assessment on the seismic behaviour of precast hollowcore slab to beam connection with different connection details

Vinutha D., Vidjeapriya R., Jaya K. P.

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 3

art. no. e167, 2024

EN

This study evaluates the cyclic response of the Precast Hollow Core Slab (PHCS) to the beam connection by proposing a novel connection detail. The evaluation involved, three different connection details, namely, (1) Continuity rebar and U-type Core Rebar Discrete with 100 mm ledge width (CUCRD_100); (2) continuity rebar and Core Rebar Combined with 100 mm ledge width (CCRC_100); and (3) continuity rebar and Core Rebar Combined with Ties along with 100 mm ledge width (CCRCT_100) were experimentally validated. These were validated through experimental testing, comparing their performance with a reference specimen that adhered to New Zealand guidelines using Continuity rebar and Core Rebar Discrete with 100 mm ledge width (CCRD_100). Displacement controlled reverse cyclic loading, following the ACI T1.1–0.1 protocol, was applied to the end of a hollow core slab for the experimental testing. The structural performance of all four connections considered failure pattern, strength, hysteretic behaviour, energy dissipation, displacement ductility, stiffness degradation, and equivalent viscous damping. The overall seismic efficiency of the connections was assessed using ACI 374.1–05 approval criteria. The experimental results proved that the peak load-carrying capacity for CCRCT_100 specimen was observed to be greater in both directions of loading (positive and negative) when compared with the other connection detailing. The presence of transverse reinforcement enhanced the confining capacity of the concrete in the joint region which substantially increased the ductility and dissipation of energy in CCRCT_100 specimen. The seismic performance of every connection specimen was favourable, and they all met the ACI 374.1–05 approval standards.

11

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.

12

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.

13

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

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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.

14

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

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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.

15

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.

16

Influence of the PZT actuator asymmetry on the LQR control parameters in the active reduction vibrations of beams

Kuras Romuald

Vibrations in Physical Systems

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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.

17

Analysis of deflection in visco-thermoelastic beam resonators subjected to harmonic loading

Chopra Deepti, Singh Prince

International Journal of Applied Mechanics and Engineering

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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.

18

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.

19

Asymmetrical PZT Applied to Active Reduction of Asymmetrically Vibrating Beam – Semi-Analytical Solution

Brański Adam, Kuras Romuald

Archives of Acoustics

|

2022

|

Vol. 47, No. 4

555--564

EN

The article extended the idea of active vibration reduction of beams with symmetric modes to beams with asymmetric modes. In the case of symmetric modes, the symmetric PZT (s-PZT) was used, and the optimization of the problem led to the location of the s-PZT centre at the point with the greatest beam curvature. In the latter case, the asymmetric modes that occur due to the addition of the point mass cause an asymmetric distribution of the bending moment and transversal displacement of a beam. In this case, the optimal approach to the active vibration reduction requires both new asymmetric PZT (a-PZT) and its new particular distribution on the beam. It has been mathematically determined that the a-PZT asymmetry point (a-point), ought to be placed at the point of maximum beam bending moment. The a-PZT asymmetry was found mathematically by minimizing the amplitude of the vibrations. As a result, it was possible to formulate the criterion of the maximum bending moment of the beam. The numerical calculations confirmed theoretical considerations. So, it was shown that in the case of asymmetric vibrations, the a-PZTs reduced vibrations more efficiently than the s-PZT.

20

Zastosowanie zogniskowanych wiązek mikrofal do wytwarzania silnych impulsowych pól magnetycznych

Bednarek Stanisław

Przegląd Elektrotechniczny

|

2021

|

R. 97, nr 8

31--35

PL

W artykule przedstawiono projekt układu doświadczalnego do badania materiałów w silnych, impulsowych polach magnetycznych. Do wytwarzania pola wykorzystano ogniskowanie wiązek mikrofal w układzie złożonym z magnetronów albo wirkatorów oraz falowodów, soczewek i zwierciadeł parabolicznych. Wykonane obliczenia pokazały możliwość otrzymania pól magnetycznych o indukcji 9,64 T w obszarze o rozmiarach 10 mm oraz 967 T w obszarze o rozmiarach 0,1 mm. Przedyskutowano zalety i wady proponowanego układu i oceniono jego wykonalność.

EN

The experimental setup to research of materials in the pulsed high magnetic fields is presented. Focusing of the microwave beams in the system composed of magnetrons or vircators, and waveguides, parabolic lenses and mirror is exploited in the setup. Executed computation shows possibilities obtaining of the magnetic.