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1

The concept of using wind turbine propellers in the construction of acoustic screens as an example of a circular economy model

Broniewicz Mirosław, Broniewicz Filip, Dec Karolina, Skubiak Beata

Economics and Environment

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2023

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No. 4

1--18

EN

This paper aims to conceptualise the construction of noise barrier panels from components recovered from used wind turbine propellers. At present, they are mainly waste, but many ideas for their reuse are emerging. Based on previously conducted material tests, the strength of the panels was calculated in accordance with EN 14388. The finite element method and the ANSYS space-claim programme were used to analyse the strength and generate a 3D numerical model of the cracked wind turbine propeller panels. The permissible values given in the standard were compared with those obtained for the deflection of the component.

PL

Celem artykułu jest koncepcja budowy paneli ekranów akustycznych z elementów odzyskanych ze zużytych śmigieł turbin wiatrowych. Obecnie stanowią one głównie odpady, lecz pojawia się wiele pomysłów ich powtórnego wykorzystania. Na podstawie przeprowadzonych wcześniej badań materiałowych obliczono wytrzymałość paneli zgodnie z normą PN-EN 14388. Do analizy wytrzymałości i wygenerowania trójwymiarowego modelu numerycznego pękniętych paneli śmigła wiatraka wykorzystano metodę elementów skończonych oraz program ANSYS Space-claim. Dopuszczalne wartości podane w normie zestawiono z wartościami uzyskanymi dla ugięcia elementu.

2

The effect of freeze-thaw cycles on flexural behaviour of FRP-reinforced ECC beams

Wang Yi, Wang Guan, Guan Zhongwei, Ashour Ashraf, Ge Wenjie, Zhang Pu, Lu Weigang, Cao Dafu

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

265--288

EN

This paper presents experimental and theoretical investigations on the flexural utilised of FRP (fibre-reinforced polymer) rebar-reinforced ECC (engineered cementitious composite) beams subjected to freeze–thaw cycles. Eight FRP-reinforced specimens after subjected to 0, 50, 100 and 150 cycles of freeze–thaw were tested to failure under flexural loading. Experimental results show that the moment capacity decreases with the increase of freeze–thaw cycles regardless of the material used, but the decreasing rate of the reinforced ECC specimen is lower than that of the conventional reinforced concrete specimen. The bearing capacity, deflection and crack width of the reinforced ECC specimens under quasi-permanent combination of moments are 1.13 ~ 1.21, 0.66 ~ 0.90 and 0.71 times of those of the conventional reinforced concrete specimens, respectively. Due to the excellent tensile and durability performance of ECC materials, bearing capacity, stiffness and crack resistance of FRP-reinforced ECC beams are enhanced compared with their conventional counterparts, particularly with more freeze–thaw cycles. Based on the formulae from ACI 440 and GB 50608, taking into account of the contribution of ECC material and balanced reinforcement ratio, the simplified formulae are developed to estimate the moment capacity and stiffness of the FRP-reinforced ECC beams. The results predicted on the moment capacity and deflection are in good agreement with the corresponding experimental measurements.

3

Flexural and shear behavior of reinforced concrete beams strengthened with carbon textile reinforced concrete

Nguyen H. C., Ngo D. Q.

Archives of Civil Engineering

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2020

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Vol. 66, nr 3

407--426

EN

Recently, textile reinforced concrete (TRC) has been intensively studied for strengthening reinforced concrete (RC) and masonry structures. This study is to experimentally explore the effectiveness of application of carbon TRC to strengthen RC beam in flexure and shear. Concerning the cracks formation, failure modes, ultimate strength and overall stiffness, the performance of the strengthened beams compared to the control beams were evaluated from two groups of tests. The test results confirm that the TRC layers significantly enhance both shear and flexural capacity of RC beams in cracking, yielding and ultimate loads. All of the tested specimens were also modelled using ABAQUS/CAE software, in order to validate the experimental results. The numerical results show that the simulation models have good adaptability and high accuracy.

4

Studying the Flexural Behavior of Reinforced Concrete Beams under the Effect of High Temperature: A Finite Element Model

Al-Baijat Hamadallah, Alhawamdeh Mohammad, Khawaldeh Aya

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 2

150--156

EN

The strength of concrete elements can be greatly affected by elevated temperature as in fires, and so a great concern must be taken regarding its behavior under such condition. In this paper, a finite element model was built up using ABAQUS software to investigate the flexural behavior of reinforced concrete (RC) beams subjected to service load under elevated temperature. The beam was simply supported and was loaded at one-third and two-third of span length. The study consisted of three RC beams models; the first model simulated a control beam specimen at ambient temperature 20 °C, while the other two models demonstrated damaged beams specimens according to two high temperatures 400 °C and 800 °C, respectively. Each RC beam had 2 m span length, 300 mm height and 200 mm width. The steel reinforcement configuration was 3ϕ16 mm (Grade 60) main bars at the positive moment region in the beam bottom, 2ϕ14 mm (Grade 60) secondary bars at the beam top, and ϕ10 mm /150 mm closed stirrups. The model was validated by comparing its results with the theoretical results from ACI code and literature. Several mechanical properties were investigated including concrete compressive strength, modulus of elasticity, and reinforcing steel yielding strength. The test results showed a reduction in the flexural capacity of the RC beams, tested at 400 °C and 800 °C, of 17.6% and 88.2%, respectively, with respect to the control beam. The maximum service load carried by the beam, at one-third and two-third of the span length, decreased by 17.1% and 88.1% for the 400 ℃ and 800 ℃ high temperature, respectively. The results also showed an increase in deflection when the temperature increased due to the loss in stiffness.

5

Research progress on the flexural behaviour of externally bonded RC beams

Qeshta I. M. I., Shafigh P., Jumaat M. Z.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 4

982--1003

EN

The flexural behaviour of strengthened reinforced concrete (RC) beams is more complicated compared to the normal beams due to the different bond conditions and properties of the externally bonded material. A significant number of research studies have been reported on the use of different types of material for flexural strengthening of RC beams using the external bonding (EB) technique. Although most research has focused on the conventional strengthening materials, namely, steel plates, FRP and ferrocement; unconventional materials, such as sprayed FRP and cement-based composites, have shown that they also have a significant effect on the behaviour of bonded beams. This paper presents a comprehensive state-of-the-art review of the different materials used for strengthening RC beams using the EB technique and their evaluation criteria. The behaviour of the strengthened beams is discussed in terms of load carrying capacity, stiffness under service loads, and ductility and failure modes. In addition, the effect of elevated temperatures on the externally bonded materials is also discussed. The critical review of the existing data can help for a better utilization and usage of the different materials for strengthening projects, which contributes significantly to the current efforts of developing optimum and feasible strengthening systems.

6

Numerical study of the flexural behaviour of GFRP RC beams

Pawłowski D., Szumigała M.

Architecture Civil Engineering Environment

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2015

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Vol. 8, no. 2

71--76

EN

Fiber-reinforced polymer (FRP) bars have been commercially available in civil engineering in the last twenty years. Due to their mechanical and physical properties, the behaviour of FRP reinforced concrete (RC) members is significantly different to that of traditional steel RC. This paper presents the results and discussion of a numerical study of the flexural behaviour of simply supported glass fiber-reinforced polymer (GFRP) RC beams under short-term static loads. The numerical analysis was performed using the Finite Element Method (FEM). All calculations were carried out in the environment of the Abaqus. The main objective of this paper was to investigate the flexural behaviour of GFRP RC members depending on the reinforcement ratio. The results of the numerical analysis were examined and compared with code formulations and with the results of experiments.

PL

Zbrojenie kompozytowe (FRP) jest wykorzystywane w budownictwie od ponad dwudziestu lat. Ze względu na jego mechaniczne i fizyczne właściwości, zachowanie elementów zbrojonych prętami niemetalicznymi jest odmienne od zachowania klasycznych elementów żelbetowych. W pracy przedstawiono wyniki symulacji komputerowej zachowania swobodnie podpartych belek zbrojonych prętami z włókna szklanego (GFRP) poddanych działaniu krótkotrwałego obciążenia statycznego. Badanie numeryczne przeprowadzono przy zastosowaniu oprogramowania Abaqus wykorzystującego Metodę Elementów Skończonych (MES). Głównym celem pracy było zbadanie wpływu stopnia zbrojenia na nośność i sztywność elementów zbrojonych prętami GFRP. Wyniki symulacji komputerowej porównano z wynikami normowymi oraz z rezultatami doświadczeń laboratoryjnych.