scholarly journals Evaluation of the Performance and Ductility Index of Concrete Structures Using Advanced Composite Material Strengthening Methods

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4239
Author(s):  
Tae-Kyun Kim ◽  
Jong-Sup Park
Keyword(s):  
Prestressed Concrete ◽  
Evaluation Method ◽  
Concrete Structures ◽  
Area Ratio ◽  
Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Rc Structures ◽  
Ductility Index ◽  
Concrete Crack ◽  
Index Evaluation

The performance of concrete structures deteriorates over time. Thus, improving their performance using fiber-reinforced polymers (FRPs), PS strands, and various strengthening methods is important. Reinforced concrete (RC) and prestressed concrete (PSC) structures develop initial cracks in concrete during bending tests, and destruction occurs over a certain period of time after a certain load is generated, and then after the reinforcements and strands yield. However, in the case of FRP structures, after an initial concrete crack occurs, FRPs exhibit a rapid shape deformation of the structure after yielding. Thus, in this study we used FRP and PS strand materials and evaluated the ductility index using the load-displacement results obtained from structural tests conducted using various strengthening methods. The ductility index evaluation method compares and analyzes the change rates in the ductility index of PSC and RC structures based on a method that uses structural deflection and the derivation of the energy area ratio. The ductility evaluation results based on the energy area ratio at the crack, yield, and ultimate points showed that all the RC structures, except for the specimens strengthened with reinforcing materials from company H, were in the ductility and semi-ductility sections. Thus, all the PSC structures, except for the control specimens and PH4NP, were found to be brittle.

scholarly journals Evaluation of Concrete Structures Reinforced with Fiber Reinforced Polymers Bars: A Review

2017 ◽  
Vol 7 (5) ◽  
pp. 165-175 ◽  
Author(s):  
Masoud Abedini ◽  
Ebrahim Akhlaghi ◽  
Javad Mehrmashhadi ◽  
Mohamed H Mussa ◽  
Mohammad Ansari ◽  
...  
Keyword(s):  
Concrete Structures ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Reinforced Polymers

scholarly journals Durability Issues and Corrosion of Structural Materials and Systems in Farm Environment

2020 ◽  
Vol 10 (3) ◽  
pp. 990 ◽  
Author(s):  
Chrysanthos Maraveas
Keyword(s):  
Concrete Structures ◽  
Animal Manure ◽  
Fiber Reinforced Polymers ◽  
Pig Manure ◽  
Exposure Limits ◽  
Viable Option ◽  
Reinforced Polymers ◽  
Metal Structures ◽  
Farm Structures ◽  
Materials Used

This review paper investigated the durability and corrosion of materials used in the construction of agricultural buildings. Even though concrete and metal were the materials of choice in the construction of farm structures, they are susceptible to corrosion and environmental degradation. Acid attacks result in the oxidation of metals and mass losses and reduced compressive strength of the metal structures. Concrete structures are degraded in high humidity environments, such as lagoons, agricultural effluents, and animal manure. Poultry, cow, and pig manure contain variable quantities of corrosion-inducing chemicals, such as sulfates, nitrates, chlorides, hydrogen sulfide, and ammonia. However, the degradation of concrete structures can be mitigated by the utilization of modified concrete containing sulfur, fly ash, silica fume, and nanoparticles such as silica. Concrete structures made of fiber-reinforced polymers are less prone to corrosion and are more durable. The design for durability has also emerged as a viable option for optimizing the service life of agricultural buildings by adhering to the exposure limits.

scholarly journals EXPERIMENTAL ANALYSIS ON FLEXURAL BEHAVIOUR OF CONCRETE BEAMS WITH GFRP REINFORCEMENT / LENKIAMŲJŲ ELEMENTŲ, ARMUOTŲ STIKLO PLUOŠTO ARMATŪRA, ELGSENOS STATMENAJAME PJŪVYJE EKSPERIMENTINIS TYRIMAS

2013 ◽  
Vol 5 (2) ◽  
pp. 76-81 ◽  
Author(s):  
Edgaras Atutis ◽  
Juozas Valivonis ◽  
Mantas Atutis
Keyword(s):  
Flexural Strength ◽  
Prestressed Concrete ◽  
Concrete Beams ◽  
Concrete Structures ◽  
Experimental Investigations ◽  
Reinforced Polymers ◽  
Time Period ◽  
Glass Fibre Reinforced ◽  
Metallic Reinforcement ◽  
Gfrp Reinforcement

The current economic pressures on utilities to extend a service life of structural concrete mean that concrete structures may have to perform safety functions for a time period significantly greater than their initial design life. However, the structural design and construction requirements for concrete structures with non-metallic reinforcement are very unique and not complete. This paper aims to provide experimental investigations of concrete beams reinforced with GFRP (glass fibre reinforced polymers) based on flexural strength. Both reinforced and prestressed concrete beams have been tested. Together with the strength characteristics, the effect of pre-stress on deflection and cracking distribution has been mainly governed by the stress–strain laws of reinforced concrete. The work is resulted in design code equations for the prediction of the ultimate flexural strength. The influence of the effect of prestressing on the deflection and cracking was analysed. Santrauka Dėl dabartinės ekonominės situacijos vis labiau siekiama, kad konstrukcinis betonas būtų naudojamas kuo ilgiau. Ypač su sauga susijusioms gelžbetoninėms konstrukcijoms dažnai keliami reikalavimai, kad per eksploatacinį šių konstrukcijų laikotarpį pagrindinės betono savybės liktų nepakitusios, lyginant su projektinėmis vertėmis. Vis dėlto reikalavimai, keliami šių konstrukcijų eksploatavimui, yra unikalūs, tačiau nėra visiškai apibrėžti. Straipsnyje aprašomi sijų, armuotų stiklo pluošto armatūra, eksperimentiniai tyrimai, kuriuose buvo nagrinėjama šių sijų laikomoji galia statmenajame pjūvyje. Buvo bandomos sijos, armuotos išilgine iš anksto įtempta stiklo pluošto armatūra, ir sijos, armuotos neįtemptąja stiklo pluošto armatūra. Gautos statmenojo pjūvio laikomosios galios lyginamos su įvairiomis projektavimo normomis ir rekomendacijomis, analizuojama išankstinio įtempimo reikšmė sijų įlinkiui bei pleišėtumui.

scholarly journals FRP REINFORCEMENT FOR CONCRETE STRUCTURES: STATE-OF-THE-ART REVIEW OF APPLICATION AND DESIGN

2014 ◽  
Vol 5 (4) ◽  
pp. 147-158 ◽  
Author(s):  
Eugenijus Gudonis ◽  
Edgaras Timinskas ◽  
Viktor Gribniak ◽  
Gintaris Kaklauskas ◽  
Aleksandr K. Arnautov ◽  
...  
Keyword(s):  
Material Properties ◽  
Structural Engineering ◽  
State Of The Art ◽  
Concrete Structures ◽  
Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Promising Alternative ◽  
Frp Composites ◽  
Structural Problems ◽  
Concrete Elements

Fiber reinforced polymers (FRPs) are considered to be a promising alternative to steel reinforcement, especially in concrete structures subjected to an aggressive environment or to the effects of electromagnetic fields. Although attempts to develop effective reinforcement have been followed, the application of FRPs remains limited by the solution to simple structural problems that mainly appear due to the absence of design codes, significant variation in the material properties of FRP composites and limited knowledge gained by engineers as regards the application aspects of FRP composites and structural mechanics of concrete elements reinforced with FRPs. To fill the latter gap, the current state-of-the-art report is dedicated to present recent achievements in FRPs applying practice to a broad engineers’ community. The report also revises the manufacturing process, material properties, the application area and design peculiarities of concrete elements reinforced with FRP composites. Along the focus on internal reinforcement, the paper overviews recent practices of applying FRP reinforced concrete (RC) elements in structural engineering. The review highlights the main problems restricting the application of FRPs in building industry and reveals the problematic issues (related to the material properties of the FRP) important for designing RC following the formulation of targets for further research.

scholarly journals An Experimental Interpretation of High-Performance Fiber-Reinforced Polymer Concrete with FNN Paradigms

2020 ◽  
Vol 8 (5) ◽  
pp. 2624-2632
Keyword(s):  
High Performance ◽  
Fiber Reinforced Polymers ◽  
Polymer Concrete ◽  
Fiber Reinforced ◽  
Reinforced Polymers ◽  
Rc Structures ◽  
Fuzzy Neural ◽  
High Performance Fiber ◽  
Design Defects ◽  
The Impact

Strengthening and enhancing of Reinforced Concrete (RC) structural components are important to broaden its administration period, overcoming the first structure limits and to limit the impact of construction defects as well as the design defects. In this work, Fiber Reinforced Polymers (FRPs) is utilized as to strengthen RC structures. In this paper, the utilization of FRP such as Sisal, Jute, and Coir in concrete structures is being examined for its viability in upgrading structural execution both regarding strength and ductility. The structural behavior of FRP specimen is examined by experimental and numerical examination by estimating the parameters, for example, compressive strength, tensile strength, ductility, and deflection. Here, we utilized the Fuzzy Neural Network (FNN) procedure to test the strength of specimen. At the point, when compared with existing work, the proposed FNN model achieves the greatest performance in terms of all parameters for the fiber reinforced specimen under various loaded condition.

scholarly journals An EMI-Based Clustering for Structural Health Monitoring of NSM FRP Strengthening Systems

Sensors ◽  
2019 ◽  
Vol 19 (17) ◽  
pp. 3775 ◽  
Author(s):  
Ricardo Perera ◽  
Lluis Torres ◽  
Antonio Ruiz ◽  
Cristina Barris ◽  
Marta Baena
Keyword(s):  
Failure Modes ◽  
Damage Identification ◽  
Concrete Structures ◽  
Experimental Tests ◽  
Complex Problem ◽  
Concrete Cover ◽  
Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Near Surface ◽  
Electromechanical Impedance

The use of fiber-reinforced polymers (FRP) in civil construction applications with the near-surface mounted (NSM) method has gained considerable popularity worldwide and can produce confident strengthening and repairing systems for existing concrete structures. By using this technique, the FRP reinforcement is installed into slits cut into the concrete cover using cement mortar or epoxy as bonding materials, yielding an attractive method to strengthen concrete structures as an advantageous alternative to the external bonding of FRP sheets. However, in addition to the two conventional failure modes of concrete beams, sudden and brittle debonding failures are still likely to happen. Due to this, a damage identification technology able to identify anomalies at early stages is needed. In this work, some relevant cluster-based methods and their adaptation to electromechanical impedance (EMI)-based damage detection in NSM-FRP strengthened structures are developed and validated with experimental tests. The performance of the proposed clustering approaches and their evaluation in comparison with the experimental observations have shown a strong potential of these techniques as damage identification methodology in an especially complex problem such as NSM-FRP strengthened concrete structures.

scholarly journals Advancements in shear strengthening of prestressed concrete I-girders using fiber reinforced polymers

2021 ◽  
Author(s):  
Muhammad Arslan Yaqub ◽  
Stijn Matthys ◽  
Christoph Czaderski
Keyword(s):  
Prestressed Concrete ◽  
Failure Modes ◽  
Rational Solution ◽  
Fiber Reinforced Polymers ◽  
Shear Reinforcement ◽  
Shear Strengthening ◽  
Reinforced Polymers ◽  
The Past ◽  
Externally Bonded ◽  
Fibre Reinforced Polymer

<p>A number of attempts were made by different researchers in the last couple of decades to strengthen prestressed concrete (PC) I-girders in shear using externally bonded FRP (fibre reinforced polymer) reinforcement. The unanimous observation reported in the literature is the early debonding of FRP shear reinforcement around the internal angles of the I-section. Because of this undesirable phenomenon, the strength of the FRP is utilized inefficiently. This paper gives an overview of the techniques utilized in the past and their relative performance in order to develop a rational solution to the debonding problem, particularly for I-sections. The anchoring techniques used in the past includes different types of FRP anchors as well as mechanical anchors to protect FRP shear reinforcement from debonding on the I-section. It can be concluded that the definite solution to the debonding problem on I-sections has not been obtained yet. This is because of the complex failure modes of FRP shear reinforcement and PC I-girders.</p>

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