To see the other types of publications on this topic, follow the link: Concrete beams Fiber-reinforced concrete.
Journal articles on the topic 'Concrete beams Fiber-reinforced concrete'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Concrete beams Fiber-reinforced concrete.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Zainurrahman, Eko Darma, and Sri Nuryati. "Carbon Fiber Reinforced Polymer Sebagai Perkuatan Lentur pada Balok Beton." BENTANG : Jurnal Teoritis dan Terapan Bidang Rekayasa Sipil 8, no. 1 (2020): 20–28. http://dx.doi.org/10.33558/bentang.v8i1.1947.
Full textAbstract:
Concrete Beams can experience a sudden collapse when overload because of its brittle characteristic. The use of Carbon Fiber Reinforced Polymer (CFRP) on concrete beams externally as external confinement is predicted to improve concrete mechanics properties, increase the ductility and capacity of concrete, and the flexural strength of concrete beams. An experimental study on the reinforcement of concrete beams with Carbon Fiber Reinforced Polymer (CFRP) was carried out to estimate the effectiveness of CFRP on concrete structures as a concrete beam flexural reinforcement material. Two types of concrete beams are provided in this study to test the flexural strengthening effect of the externally bound CFRP composite. First type of concrete beam used for testing is a normal concrete beams, whereas the second tested beam, the CFRP was laminated by coating the beams with Fiber. The dimensions of both types are 15cm x15cm with a length of 55cm footing range. Testing result obtained the compressive strength was 23,29 MPa, flexural strength of normal and CRFP concretes were 33,41 Kg/cm2 and 48,07 Kg/cm2 respectively. It was concluded that the use of CRFP at the concrete beam increases flexural strength up to 44% with the ratio of 143 %.
2
Wang, Zuohu, Zhanguang Gao, Yuan Yao, and Weizhang Liao. "Experimental investigation on the seismic behavior of concrete beams with prestressing carbon fiber reinforced polymer tendons." Science Progress 103, no. 1 (2019): 003685041988523. http://dx.doi.org/10.1177/0036850419885235.
Full textAbstract:
Seven prestressed concrete beams and one normal concrete beam were tested to study the seismic performance of concrete beams with prestressing carbon fiber reinforced polymer tendons. The failure modes, hysteretic curves, ductility, stiffness degeneration, and energy dissipation capacity were studied systematically. This study shows that the partial prestressing ratio is the main factor that affects the seismic performance of carbon fiber reinforced polymer prestressed concrete beams. The beam is more resilient to seismic loads as the partial prestressing ratio decreases. Under the same partial prestressing ratio value, the energy dissipation capacity of prestressed concrete beams with unbonded carbon fiber reinforced polymer tendons was better than that of prestressed beams with bonded carbon fiber reinforced polymer tendons. When combining both bonded and unbonded prestressing carbon fiber reinforced polymer tendons, the ductility index of concrete beams was improved. Compared with that of fully unbonded and fully bonded carbon fiber reinforced polymer prestressed concrete beams, the ductility index of concrete beams with combined bonded and unbonded prestressing tendons increased by 26% and 12%, respectively.
3
Majdzadeh, Fariborz, Sayed Mohamad Soleimani, and Nemkumar Banthia. "Shear strength of reinforced concrete beams with a fiber concrete matrix." Canadian Journal of Civil Engineering 33, no. 6 (2006): 726–34. http://dx.doi.org/10.1139/l05-118.
Full textAbstract:
The purpose of this study was to investigate the influence of fiber reinforcement on the shear capacity of reinforced concrete (RC) beams. Both steel and synthetic fibers at variable volume fractions were investigated. Two series of tests were performed: structural tests, where RC beams were tested to failure under an applied four-point load; and materials tests, where companion fiber-reinforced concrete (FRC) prisms were tested under direct shear to obtain material properties such as shear strength and shear toughness. FRC test results indicated an almost linear increase in the shear strength of concrete with an increase in the fiber volume fraction. Fiber reinforcement enhanced the shear load capacity and shear deformation capacity of RC beams, but 1% fiber volume fraction was seen as optimal; no benefits were noted when the fiber volume fraction was increased beyond 1%. Finally, an equation is proposed to predict the shear capacity of RC beams.Key words: shear strength, fiber-reinforced concrete, RC beam, stirrups, energy absorption capacity, steel fiber, synthetic fiber.
4
Malla, Prafulla B., Hong Zhou, and Yi Che. "Cyclic Flexural Behavior of Reinforced Concrete Beams." E3S Web of Conferences 38 (2018): 03022. http://dx.doi.org/10.1051/e3sconf/20183803022.
Full textAbstract:
The present study aims at investigating the cyclic flexural behavior of reinforced concrete beams with varying depths. Five reinforced concrete beams with beam depth ranging from 250 mm to 750 mm were tested under reversed cyclic loading and the influence of beam depth on the flexural strength and ductility of reinforced concrete beams was investigated. In addition, OpenSees was used to model the test specimens and the analytical results were compared with the experimental reuslts. It is shown that there is no apparent size effect on the normalized ultimate flexural strength of the tested beams, while for the displacement ductility factor, a significant size effect is observed. Load-deflection hysteric curves of test specimens obtained by the fiber-based element of OpenSees with Concrete03 and Hysteric models are in good agreement with those from experimental tests.
5
Wang, Jun, Huan Jun Ye, Zhi Wei Sun, and Wei Chen. "Experiment on the Crack and Deflection of Basalt Fiber Reinforced Concrete Beams." Advanced Materials Research 243-249 (May 2011): 1058–61. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.1058.
Full textAbstract:
In order to research the influence of basalt fiber on the crack and deflection of the reinforced concrete beams, four basalt fiber reinforced concrete beams with the key parameters of length which were 12mm and 30mm and volume ratio which were 0.1% and 0.2% were designed and made. The test data was obtained through the bending experiment and the comparison with the common reinforced concrete beam. The result shows that it is obvious to control the crack and deflection of the test beams with the increasing of basalt fiber characteristic parameters. The calculation method of the maximum crack width of the basalt fiber reinforced concrete beams were presented based on the method of common concrete beam, which can provide the theoretical basis for the engineering practice.
6
Salleh, Norhafizah, Abdul Rahman Mohd Sam, Jamaludin Mohd Yatim, and Mohd Firdaus bin Osman. "Flexural Behaviour of Reinforced Concrete Beam with Glass Fiber Reinforced Polymer (GFRP) Bar Strengthened with Carbon Fiber Reinforced Polymer (CFRP) Plate." Advanced Materials Research 1051 (October 2014): 748–51. http://dx.doi.org/10.4028/www.scientific.net/amr.1051.748.
Full textAbstract:
The use of glass-fiber-reinforced polymer (GFRP) bar to replace steel reinforcement in concrete structures is a relatively a new technique. The GFRP bars possess mechanical properties different from steel bars, including high tensile strength combined with low elastic modulus and linear stress–strain relationship up to failure. Therefore, design procedures and process should account for these properties. This paper presents the experimental work on the flexural behavior of concrete beam reinforced with GFRP bars and strengthen with CFRP plate. A total of ten reinforced concrete beams reinforced with either steel and GFRP bars were cast and tested under four point loads. Eight concrete beams (200x250x2800mm) were reinforced with 13mm diameter GFRP bars together with strengthening using CFRP plate and two control beams reinforced with 12mm diameter steel bars were tested. The experimental results show that although the stiffness of the beams reduced but the ultimate load of the GFRP reinforced concrete beam is bigger than steel reinforced beam. It was also found that strengthening using CFRP plate will further enhanced the flexural performance of the beams with GFRP bars.
7
Oleg, Radaikin, and Sharafutdinov Linar. "Reinforced concrete beams strengthened with steel fiber concrete." IOP Conference Series: Materials Science and Engineering 890 (August 13, 2020): 012045. http://dx.doi.org/10.1088/1757-899x/890/1/012045.
Full text
8
Chen, Wei, Xiang Peng Li, Ting Ting Chen, Xiao Yang Wang, and Chao Chao Ma. "Experimental Research on Crazing-Resistance of Inclined Section of Basalt Fiber Reinforced Concrete Beams." Applied Mechanics and Materials 584-586 (July 2014): 899–903. http://dx.doi.org/10.4028/www.scientific.net/amm.584-586.899.
Full textAbstract:
In order to research the influence of the shear capacity of reinforced concrete beam with the incorporation of basalt fiber, four basalt fiber reinforced concrete beams with parameters of length and volume ratio were designed and made. The fiber lengths were 12mm and 30mm, and the volume ratios were 1‰ and 2‰. The test data of basalt fiber reinforced concrete was obtained through the shear experiments and comparison with the common reinforced concrete beam. The results of the experiment show that the cracking load of the basalt fiber reinforced concrete beam increase obviously with the growing of fiber characteristic parameters, and effectively reduce the diagonal crack width.
9
Qu, Hong Chang, Hong Yuan Li, and Xuan Zhang. "Flexural Tests of Fiber-Reinforced-Concrete Beams Reinforced with FRP Rebars." Applied Mechanics and Materials 166-169 (May 2012): 1797–800. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.1797.
Full textAbstract:
This paper investigates the flexural performance of FRP/FRC hybrid reinforcement system as well as FRP/plain concrete beams. Test results showed that the crack widths of FRP/FRC beams were smaller than those of FRP/plain concrete beams at the different corresponding load. With the increase of load, the crack spacing slightly decreased. The plain concrete beams failed in a more brittle mode than the FRC beams. Once they reached their ultimate moments, the load dropped fleetly. Compared to the companion beam, the addition of fibers improved the flexural behavior.
10
Chan, Ly, Ganchai Tanapornraweekit, and Somnuk Tangtermsirikul. "Investigation of Aramid Fibers Compared with Steel Fiber on Bending Behavior of Hybrid RC Beams." Materials Science Forum 860 (July 2016): 117–20. http://dx.doi.org/10.4028/www.scientific.net/msf.860.117.
Full textAbstract:
This paper presents an experimental study on bending behavior of aramid and steel fiber reinforced concrete (AFRC and SFRC) members. The objective is to investigate effects of two types of aramid fiber and one type of steel fiber in hybrid reinforced concrete (RC) beams. The term hybrid beam is defined as the beam with fiber reinforced concrete (FRC) cast in tension zone and normal concrete (without fiber) cast in compression zone of the beam. The diameter of aramid fiber (AF) is 0.5mm and the surface condition is twist fiber consisting of two single fibers. The fiber lengths are 30mm and 40mm for two types of aramid fiber. The diameter of steel fiber (SF) is 0.6mm and the length is 33mm with hooked ends. Four reinforced concrete (RC) beams with a dimension of 150×200×2100 mm3 were designed to undergo flexural failure. All the tested beams are with the same reinforcement ratio (0.93%), having a fiber volume fraction (Vf) of 1% for each type of fiber. One RC beam without fiber was prepared and tested as a controlled specimen. The height of the FRC tension zone at ultimate state was calculated to be 170mm. Load capacity, average and maximum crack widths of hybrid aramid and steel fiber reinforced concrete beams (HAFRCs & HSFRC) under four-point bending tests were discussed.
11
Tavares, D. H., J. S. Giongo, and P. Paultre. "Behavior of reinforced concrete beams reinforced with GFRP bars." Revista IBRACON de Estruturas e Materiais 1, no. 3 (2008): 285–95. http://dx.doi.org/10.1590/s1983-41952008000300004.
Full textAbstract:
The use of fiber reinforced polymer (FRP) bars is one of the alternatives presented in recent studies to prevent the drawbacks related to the steel reinforcement in specific reinforced concrete members. In this work, six reinforced concrete beams were submitted to four point bending tests. One beam was reinforced with CA-50 steel bars and five with glass fiber reinforced polymer (GFRP) bars. The tests were carried out in the Department of Structural Engineering in São Carlos Engineering School, São Paulo University. The objective of the test program was to compare strength, reinforcement deformation, displacement, and some anchorage aspects between the GFRP-reinforced concrete beams and the steel-reinforced concrete beam. The results show that, even though four GFRP-reinforced concrete beams were designed with the same internal tension force as that with steel reinforcement, their capacity was lower than that of the steel-reinforced beam. The results also show that similar flexural capacity can be achieved for the steel- and for the GFRP-reinforced concrete beams by controlling the stiffness (reinforcement modulus of elasticity multiplied by the bar cross-sectional area - EA) and the tension force of the GFRP bars.
12
Zhao, Wei Jian, Jia Xin Tong, Shen Ming Yuan, and Ye Nan Guo. "Research Progress on Reinforced Concrete Composite Beam in China." Applied Mechanics and Materials 584-586 (July 2014): 939–43. http://dx.doi.org/10.4028/www.scientific.net/amm.584-586.939.
Full textAbstract:
Reinforced concrete composite beam plays a very important role in the precast concrete structure, composite beam research is critical. Based on the research results about it in China, on the one hand, from the traditional composite beams to the improved ones, the various kinds of composite beams were concluded; on the other hand, the applications of new building materials in the composite beams had been included, which included fiber reinforced cement-based composites, steel fiber reinforced concrete, reactive powder concrete and crumb rubber concrete. Through to the both related tests and theoretical studies, the progress of the composite beams was summarized. Finally, the further research was prospected.
13
Yavaş, Altuğ, Umut Hasgul, Kaan Turker, and Tamer Birol. "Effective fiber type investigation on the shear behavior of ultrahigh-performance fiber-reinforced concrete beams." Advances in Structural Engineering 22, no. 7 (2019): 1591–605. http://dx.doi.org/10.1177/1369433218820788.
Full textAbstract:
In this study, the effects of different fiber types on shear behavior (cracking pattern, shear cracking strength, ultimate shear strength, and post-cracking deformability) of ultrahigh-performance fiber-reinforced concrete beams were investigated experimentally. For this purpose, 15 ultrahigh-performance fiber-reinforced concrete beams including different steel fiber types (two straight, two hooked, and one double hooked) with three volume fractions (0.5%, 1.0%, and 1.5%) were casted without shear reinforcement and tested under four-point loading until the failure. In addition to the experimental program, three existing numerical models proposed for the shear capacity of fiber-reinforced concrete beams were investigated to show the applicability of these models to the ultrahigh-performance fiber-reinforced concrete beams. The experimental results demonstrated that the straight fiber of 13 mm is the most effective fiber type in terms of the considered parameters. However, the addition of 13-mm straight fiber with 1.5% by volume into the ultrahigh-performance fiber-reinforced concrete beam changed the failure mode from the shear to flexure without shear reinforcement.
14
Nguyen, Duy-Liem, Duc-Kien Thai, and Dong-Joo Kim. "Direct tension-dependent flexural behavior of ultra-high-performance fiber-reinforced concretes." Journal of Strain Analysis for Engineering Design 52, no. 2 (2017): 121–34. http://dx.doi.org/10.1177/0309324716689625.
Full textAbstract:
This research investigated the effects of direct tensile response on the flexural resistance of ultra-high-performance fiber-reinforced concretes by performing sectional analysis. The correlations between direct tensile and flexural response of ultra-high-performance fiber-reinforced concretes were investigated in detail for the development of a design code of ultra-high-performance fiber-reinforced concrete flexural members as follows: (1) the tensile resistance of ultra-high-performance fiber-reinforced concretes right after first-cracking in tension should be higher than one-third of the first-cracking strength to obtain the deflection-hardening if the ultra-high-performance fiber-reinforced concretes show tensile strain-softening response; (2) the equivalent bottom strain of flexural member at the modulus of rupture is always higher than the strain capacity of ultra-high-performance fiber-reinforced concretes in tension; (3) the softening part in the direct tensile response of ultra-high-performance fiber-reinforced concretes significantly affects their flexural resistance; and (4) the moment resistance of ultra-high-performance fiber-reinforced concrete girders is more significantly influenced by the post-cracking tensile strength rather than the tensile strain capacity. Moreover, the size and geometry effects should be carefully considered in predicting the moment capacity of ultra-high-performance fiber-reinforced concrete beams.
15
Ji, Chunyang, Weiwen Li, Chengyue Hu, and Feng Xing. "Data analysis on fiber-reinforced polymer shear contribution of reinforced concrete beam shear strengthened with U-jacketing fiber-reinforced polymer composites." Journal of Reinforced Plastics and Composites 36, no. 2 (2016): 98–120. http://dx.doi.org/10.1177/0731684416671423.
Full textAbstract:
Lots of studies have investigated the shear contribution of the fiber-reinforced polymer of reinforced concrete beams with externally bonded fiber-reinforced polymer (FRP). In this paper, based on more than 200 collected experimental results of reinforced concrete beams shear strengthened with U-jacketing fiber-reinforced polymer composites, four existing design guidelines on the fiber-reinforced polymer shear contribution of strengthened reinforced concrete beams are compared in terms of the effect of the shear span-to-effective depth ratio, beam size, and stirrup ratio. These three influence factors are found to play significant roles in the prediction accuracy of different design guidelines. This paper, therefore, proposes an advanced shear strength model, which considers the effect of shear span-to-effective depth ratio, beam size, and stirrup ratio. The proposed model can provide better predictions of fiber-reinforced polymer shear contribution.
16
Novak, Josef, and Alena Kohoutkova. "Optimization of Pretensioned Steel Fiber Reinforced Concrete Beam." Advanced Materials Research 1106 (June 2015): 94–97. http://dx.doi.org/10.4028/www.scientific.net/amr.1106.94.
Full textAbstract:
Pretensioned concrete beams are used as a main load bearing member for composite bridges with a span to 30 m. The advantage of longitudinal prefabrication technology of beams for small span bridges is quick installation, savings of straight supporting scaffolding of centers and formwork. The amount of labour with formwork, reinforcement and concrete including work with scaffolding of centers on site is reduced at a minimum. During searching applications of steel fiber reinforced concrete (SFRC) suitable for this kind of structure a pretensioned concrete beam suitable for a bridge bay with a span from 12 to 15 m has been chosen for an investigation. Three types of beam were manufactured for experimental tests. The beams were supposed to be a part of a bridge bay with a composite slab. These pretensioned beams were made of SFRC. In case of the experimental tests, a cast-in place concrete cover from plain concrete was casted on the top of the beams. The cast-in place concrete cover simulated a top composite slab. The bearing capacity of the beams with the cast-in place concrete cover was tested until their destruction. The tested beams showed higher bearing capacity than it was determined by a theoretical calculation. The beams also demonstrated high safety against collapse during structure overloading. The process of the experimental testing was also simulated on a numerical nonlinear model and then the results were compared. The result comparison of the both types of tests did not show any significant irregularities.
17
Lu, Zhao Hong, and Xiao Song Gu. "Cracking Behavior Analysis of Carbon Fiber Reinforced Concrete Beam." Applied Mechanics and Materials 204-208 (October 2012): 3082–85. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.3082.
Full textAbstract:
This paper analyzed the cracking behavior of carbon fiber reinforced concrete beam under static load using the finite element numerical analysis. By the way of finite element numerical simulation and the method of increasing the load gradually to analyze the carbon fiber content influence on the beam cracking, crack developing, beam deflection and beam average crack spacing. By comparing with the simulation result of common reinforced concrete beam test piece, it turned out that the carbon fiber reinforced concrete beam has a good cracking and deformation behavior under the same ratio of reinforcement. Under the same load, both the carbon fiber reinforced concrete beam and the common reinforced concrete beam have a small deformation, but the carbon fiber reinforced concrete beam showed a better resistance to deformation as the load increasing, its deflection increasing extent showed an obvious decrease compared with that of the common reinforced concrete beams. Its crack width can be revised by the common reinforced concrete beam rules.
18
Li, Xiao Yong, and Zhi Gang Zhang. "Mechanical Behavior of Reinforced Concrete Beams Externally Strengthened with Carbon Fiber Sheets." Advanced Materials Research 179-180 (January 2011): 955–59. http://dx.doi.org/10.4028/www.scientific.net/amr.179-180.955.
Full textAbstract:
Externally bonding carbon fiber reinforced polymer sheets with an epoxy resin is an effective technique for strengthening and repairing reinforced concrete beams under flexural loads. In this study, a total of seven reinforced concrete beams was tested and analyzed: two control beam and fourteen beams reinforced with one to six layers of carbon fiber sheets bonded by an inorganic epoxy. All specimens were subjected to a four-point bending test under load control while load, deflection, mid-span strain and failure mode were recorded up to failure. It is found that the load carrying capacity increases with the number of layers of carbon fiber sheet. For one to four layers of carbon fiber polymer reinforcement, the beams failed by rupture of carbon fiber polymer, while beams with five to six layers of fiber reinforced polymer reinforcement failed by carbon fiber polymer delamination. The results of the experimental clearly indicate that significant strengthening of reinforced concrete beams can be realized by bonding small amount carbon fiber reinforced polymer to the beams. The ductility of the carbon fiber polymer strengthened beams is greatly reduced compared to the control beam.
19
Tarigan, Johannes, Andrew Pakpahan, Medis Surbakti, and Nursyamsi Nursyamsi. "Analysis and experimental usage of CFRP wrap type on flexural strength of concrete beam." MATEC Web of Conferences 258 (2019): 03001. http://dx.doi.org/10.1051/matecconf/201925803001.
Full textAbstract:
Today, reinforced concrete structures are commonly used in buildings because the price cheaper than steel structures. However, many concrete structures are damaged. There are several ways to overcome this problem, and one of them is by strengthening the structure using Fiber Reinforced Polymer (FRP). This study discussed the flexural strength of reinforced concrete beams using Fiber Reinforced Polymer (FRP). In this case, the researchers used Carbon Fiber Reinforced Polymer (CFRP) Wrap Type as the external reinforcement. The beam’s dimension was 15 x 25 cm with a length of 320 cm. Based on the analysis results, the beam using CFRP Wrap type can increase the load 3.12 % times. Furthermore, the experimental results show that the beam with the CFRP type Wrap increases the load by 2.5 times. In conclusion, beams strengthened with CFRP Wrap type can inhibit initial cracks and hold the tensile and flexural strength greater than un-strengthened beams.
20
Zhao, Xia, Xiong-Jun He, and Yong-Chao Yang. "Numerical Simulation of GFRP Reinforced Concrete Beams." Advances in Materials Science and Engineering 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/5386498.
Full textAbstract:
Experiment on the constitutive model of fiber reinforced concrete with volume fraction of alkali-resistant glass fiber of, respectively, 0.0%, 0.5%, 1.0%, and 1.5% was conducted, and the constitutive relation of tension stress-strain full curve of GFRC shaft was obtained; the constitutive relation of GFRP is obtained by experiment, and the secant modulus was obtained by the fitting of univariate cubic equation. The finite element numerical simulation of GFRP fiber reinforced concrete beam was carried out, and the load deflection nephogram of fiber reinforced concrete beam, strain nephogram, crack nephogram, and GFRP stress nephogram were obtained. When the fiber content is 1.0%, the bearing capacity of GFRP reinforced concrete beams is the best, and it could play a “bridging” effect when the incorporation of fiber is within the load range of about 60%, which inhibited the developing speed of cracks, but with the gradual increase of the load, the “bridging” effect disappeared.
21
Lam, T. Q. K., T. M. D. Do, V. T. Ngo, T. T. N. Nguyen, and D. Q. Pham. "Concrete grade change in the layers of three-layer steel fibre reinforced concrete beams." Journal of Achievements in Materials and Manufacturing Engineering 1, no. 102 (2020): 16–29. http://dx.doi.org/10.5604/01.3001.0014.6325.
Full textAbstract:
Purpose: Determine the state of stress-strain, formation and development cracks, three-layer beam diagrams of load-compression stress, load-tension stress, load-vertical displacement relationships with a change in concrete grade. Design/methodology/approach: This paper presents the results of an ANSYS numerical simulation analysis involving stress-strain state and cracking of the steel fiber concrete layers of three-layer reinforced concrete beams with the upper and lower layers. With a cross-section of 150x300 mm, a total span of 2200 mm and an effective length of 2000 mm, the middle is a normal concrete layer. Under two-point loads, all the beam samples were tested. The research simulated three-layer concrete beams in different layers of beams with a change in concrete grade, and compared with and without the use of steel fibers in layers of concrete beams, including the nonlinearity of the material considered. Findings: A diagram of the formation and development of cracks in three-layer concrete beams has been constructed by the study results, determining the load at which the concrete beams begin to crack, the load at which the concrete beams are damaged. In the middle of three-layer steel fiber reinforced concrete beams, load-compression stress, loadtension stress, load-vertical displacement relationships are established. Study results show that these three-layer concrete beams appear to crack earlier than in other cases in cases 2 and 3, but the beam bearing capacity is damaged at 67 kN, the earliest in case 3. And case 6 at 116 kN is the latest. The effects of case 1 and case 3 are small compared with and without the use of steel fibers in cases, while the effects of case 5 and case 6 are very high. Research limitations/implications: The research focuses only on the change of concrete grade in the layers, but the input parameters affecting three-layer steel fiber concrete beams have not been researched, such as the number of tensile steel bars, tensile steel bar diameter, steel fiber content in concrete, thickness variation in three-layer concrete beam layers, etc. Practical implications: Provides a result of experimental study and ANSYS numerical simulation in multi-layer steel fiber concrete beams. Originality/value: The analysis of multi-layered steel fiber concrete beams using experimental and simulation methods shows that other parameters influencing the beams will continue to analysis the working stages of three-layer beams.
22
Omeman, Z., M. Nehdi, and H. El-Chabib. "Experimental study on shear behavior of carbon-fiber-reinforced polymer reinforced concrete short beams without web reinforcement." Canadian Journal of Civil Engineering 35, no. 1 (2008): 1–10. http://dx.doi.org/10.1139/l07-080.
Full textAbstract:
Recent literature emphasized the scarcity of information on the shear behavior of fiber-reinforced polymer (FRP) reinforced concrete short beams and the need to develop sufficient experimental data in this area. The present study responds to this need by conducting shear force testing on eight concrete short beams reinforced with carbon-fiber-reinforced polymer (CFRP) and four control concrete beams reinforced with steel. To ensure a shear failure, all tested beams were reinforced with only bottom longitudinal reinforcement and no web reinforcement was provided. The crack pattern, reinforcement strain, mode of failure, and shear strength and deflection of tested beams were studied. The influence of the shear span to effective depth ratio, a/d, beam effective depth, d, longitudinal reinforcement ratio, ρ, and concrete compressive strength, f ′c on the shear behavior of CFRP-reinforced concrete short beams was examined. It was observed that the experimental parameters investigated had a significant effect on the shear strength and deflection of tested beams. It was also found that the strut-and-tie method more accurately predicts the shear strength of steel-reinforced concrete short beams than it does for similar CFRP-reinforced beams and, thus, needs to be modified to be applicable for reinforced concrete beams with FRP reinforcement.
23
Neutov, Stepan, Maryna Sydorchuk, and Mykola Surianinov. "Experimental Studies of Reinforced Concrete and Fiber-Reinforced Concrete Beams with Short-Term and Long-Term Loads." Materials Science Forum 968 (August 2019): 227–33. http://dx.doi.org/10.4028/www.scientific.net/msf.968.227.
Full textAbstract:
Experimental studies of the stress-strain state of reinforced concrete and fiber-reinforced concrete beams under short-term and long-term loads were carried out. The tests were carried out on three series of beams of different types - from ordinary concrete, steel fiber concrete and combined section, when the lower zone of the beam with a height of0.5his made of steel fiber concrete, and the upper one is made of ordinary concrete. During short-term loading, the load was applied in steps with a 10-minute exposure at each step to failure or to a predetermined level of a continuously acting load. In the interval between the steps, the process of cracking was tracked. After reaching a given level of loading, the load was fixed and maintained unchanged with a spring cassette for 300 days. Deformations were measured using strain gauges and dial gauges. Deflections and relative deformations of the extreme upper and extreme lower fibers for three types of beams are determined. It has been established that stabilization of deflections in beams from steel fiber concrete occurs much earlier (100 days) than in beams made of ordinary concrete (175 days). Studies have shown that the beams of ordinary concrete in the process of long-acting load lowered the carrying capacity by 5.5%. The bearing capacity of steel concrete beams, in contrast, increased by 7.6%.
24
Xu, Qin, Wei Huang, Hao Zhen Wu, Xiao Ping Jiang, and Zhen Zhong Zhang. "Finite Element Analysis of Concrete Beams Reinforced With Fiber Reinforcing Bars." Advanced Materials Research 243-249 (May 2011): 756–60. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.756.
Full textAbstract:
Based on bending fiber reinforced concrete beam, through the nonlinear analysis, the paper discuss the constitutive models of concrete and reinforcement, the properties of their element and the models of concrete beams reinforced with FRP bars. Using nonlinear analysis and comparing numerical results with experimental results, the fiber reinforced concrete beam bending terminal numerical model constructed in this paper can simulate the entire process of internal force and deformation of fiber reinforced concrete beams, and describe cracks in the formation and extension and the failure process and failure form, which also can provide enough precision to the practical engineering and scientific research. Meanwhile, the finite element computation model verified by test can provide more reactive information to effective structure computation model.
25
Liu, Ying Li, Bing Xuan Du, and Jin Long Zhao. "The Application of CFRP Reinforced Concrete Beams." Applied Mechanics and Materials 468 (November 2013): 8–11. http://dx.doi.org/10.4028/www.scientific.net/amm.468.8.
Full textAbstract:
This paper expounds the excellent characteristics of CFRP in engineering application, analyzes the scope of application of CFRP reinforced plastics.This paper introduces the principle and the carbon fiber composite reinforcement method and frame beams and carbon fiber reinforced beam in the structure of the calculation results were analyzed .By SAP2000 software analyzing, results show that after using CFRP reinforced plastics has dramatically enhanced the bearing capacity of the frame beam, improve the ductility of the components, prolong the life span of the structure .
26
Ajwad, A., U. Ilyas, N. Khadim, Abdullah, M. U. Rashid, and A. Aqdas. "Restoring Initially Cracked Reinforced Concrete Beams utilizing Carbon Fiber Reinforced Polymer Strips." NFC IEFR Journal of Engineering and Scientific Research 7, no. 1 (2019): 30–34. http://dx.doi.org/10.24081//nijesr.2019.1.0006.
Full textAbstract:
Carbon fiber reinforced polymer (CFRP) strips are widely used all over the globe as a repair and strengthening material for concrete elements. This paper looks at comparison of numerous methods to rehabilitate concrete beams with the use of CFRP sheet strips. This research work consists of 4 under-reinforced, properly cured RCC beams under two point loading test. One beam was loaded till failure, which was considered the control beam for comparison. Other 3 beams were load till the appearance of initial crack, which normally occurred at third-quarters of failure load and then repaired with different ratios and design of CFRP sheet strips. Afterwards, the repaired beams were loaded again till failure and the results were compared with control beam. Deflections and ultimate load were noted for all concrete beams. It was found out the use of CFRP sheet strips did increase the maximum load bearing capacity of cracked beams, although their behavior was more brittle as compared with control beam.
27
Qi, Su, Ye Zhang, Shu Hao Liu, and Xiong Song. "Experimental Research of Bending Capacity of Normal Section of Steel Fiber Reinforced Concrete Wall-Beams Simply Supported." Applied Mechanics and Materials 193-194 (August 2012): 1365–70. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.1365.
Full textAbstract:
Because the joists in the wall-beams are in eccentric tension during work and the concrete tensile strength is low, the bending capacity of normal section of wall-beams is not too large. Steel fibers mixed into the concrete, playing enhancement and crack-resistance roles would lead to changes in the nature of concrete materials so that it is impossible to fully use the existing research results of ordinary concrete wall-beams simply supported when studying bending behavior of normal section of steel fiber reinforced concrete wall-beams simply supported. Therefore, it is necessary to do pilot studies on bending behavior of normal section of steel fiber reinforced concrete wall-beams simply supported. Based on the vertical static load test of 12 steel fiber reinforced concrete wall-beams simply supported specimens under different fiber volume ratio conditions, the strains of steel and concrete, cracking load, failure load and development situation in the cracks were tested while working characteristics of steel fiber reinforced concrete wall-beams simply supported were studied. This paper discussed the effect of fiber volume ratio on cracking moment and ultimate moment of steel fiber reinforced concrete wall-beams simply supported, which shows that the optimum mixing amount of steel fiber is 1.2%. The conclusion is of great significance in both theory and engineering practice, and it helps to guide the application of practical engineering.
28
Ruano, Gonzalo, Facundo Isla, Rodrigo Isas Pedraza, Domingo Sfer, and Bibiana Luccioni. "Shear retrofitting of reinforced concrete beams with steel fiber reinforced concrete." Construction and Building Materials 54 (March 2014): 646–58. http://dx.doi.org/10.1016/j.conbuildmat.2013.12.092.
Full text
29
Wang, Lei, Jiwang Zhang, Changshi Huang, and Feng Fu. "Comparative Study of Steel-FRP, FRP and Steel-Reinforced Coral Concrete Beams in Their Flexural Performance." Materials 13, no. 9 (2020): 2097. http://dx.doi.org/10.3390/ma13092097.
Full textAbstract:
In this study, a comparative study of carbon fiber reinforced polymer (CFRP) bar and steel–carbon fiber composite bar (SCFCB) reinforced coral concrete beams was made through a series of experimental tests and theoretical analyses. The flexural capacity, crack development and failure modes of CFRP and SCFCB-reinforced coral concrete were investigated in detail. They were also compared to ordinary steel-reinforced coral concrete beams. The results show that under the same conditions of reinforcement ratios, the SCFCB-reinforced beams exhibit better performance than CFRP-reinforced beams, and stiffness is slightly lower than that of steel-reinforced beams. Under the same load conditions, the crack width of SCFCB beams was between that of steel-reinforced beams and CFRP bar-reinforced beams. Before the steel core yields, the crack growth rate of SCFCB beam is similar to the steel-reinforced beams. SCFCB has a higher strength utilization rate—about 70–85% of its ultimate strength. Current design guidance was also examined based on the test results. It was found that the existing design specifications for FRP-reinforced normal concrete is not suitable for SCFCB-reinforced coral concrete structures.
30
Luan, Hai-Yang, Ying-Fang Fan, An Chen, and Shi-Yi Zhang. "Exploratory experimental study on flexural behavior of CFRP-reinforced concrete beams subjected to acidic loading effect." Advances in Structural Engineering 21, no. 14 (2018): 2184–97. http://dx.doi.org/10.1177/1369433218770533.
Full textAbstract:
This article presents an exploratory study on the flexural behavior of carbon fiber–reinforced polymer–reinforced concrete beams subjected to acidic loading effect. To this end, an artificial acid rain with a pH level of 1.5 was prepared by mixing sulfate and nitric acid solutions. Eight reinforced concrete beams with/without carbon fiber–reinforced polymer applications were constructed and conditioned using the artificial acid rain. During conditioning, bending loads were applied to the top surfaces of the beams to simulate the acidic loading action. Three carbon fiber–reinforced polymer reinforcement schemes (corrosion reinforcement, reinforcement corrosion, and cracking reinforcement) were considered. After conditioning, the length and quantity of initial cracks in the beams were recorded. A combined ultrasonic–rebound method was then adopted to measure the strength and corrosion depth of the concrete and evaluate the beams’ integrity. Next, four-point bending tests were conducted to study the beams’ flexural behavior. It can be concluded that all beams deteriorated with the increase of the corrosion time. Carbon fiber–reinforced polymer–reinforced concrete beams performed better than normal reinforced concrete beams under the acidic loading effect. The initial cracks can influence the flexural behavior of carbon fiber–reinforced polymer–reinforced concrete beams.
31
Masmoudi, R., B. Benmokrane, and O. Chaallal. "Cracking behaviour of concrete beams reinforced with fiber reinforced plastic rebars." Canadian Journal of Civil Engineering 23, no. 6 (1996): 1172–79. http://dx.doi.org/10.1139/l96-926.
Full textAbstract:
This paper presents the results of an experimental investigation on the cracking behaviour of concrete beams reinforced with fiber reinforced plastic rebars. The effects of reinforcement ratio on the cracking pattern, crack spacing, cracking moment, and crack width are investigated. The test results indicate that the reinforcement ratio has no meaningful effect on the cracking moment, which can be calculated as recommended by the ACI code. Also, the use of the equations adopted by ACI and the European codes for the prediction of crack width of conventionally reinforced concrete members is investigated and due modifications are made. Both relationships show good correlation with the test results; and the prediction of crack width of concrete beams reinforced with these two types of fiber reinforced plastic rebars is now possible. Key words: beam, cracking behaviour, cracking moment, crack width, fiber reinforced plastic, flexure, rebars, reinforced concrete, reinforcement ratio.
32
Sridhar, Radhika, and Ravi Prasad. "Static and Dynamic Responses of a Reinforced Concrete Beam Strengthened with Steel and Polypropylene Fibers." Slovak Journal of Civil Engineering 27, no. 3 (2019): 44–54. http://dx.doi.org/10.2478/sjce-2019-0021.
Full textAbstract:
AbstractThis paper describes an experimental investigation on mono steel and polypropylene (PP) fiber-reinforced concrete beams. The main aim of this present study is to evaluate undamaged and damaged reinforced concrete (RC) beams incorporated with mono fibers such as steel and PP fibers under free-free constraints. In this experimental work, a total of nine RC beams were cast and analyzed in order to study the dynamic behavior as well as the static load behavior of steel fiber-reinforced concrete (SFRCs) and polypropylene fiber-reinforced concrete (PPFRCs). Damage to the SFRC and PPFRC beams was obtained by cracking the concrete for one of the beams in each set under four-point bending tests with different percentage variations of the damage levels such as 50%, 70% and 90% of the maximum ultimate load. The fundamental natural frequency and damping values obtained through the dynamic tests for the SFRC and PPFRC beams were compared with a control RC beam at each level of damage that had been acquired through static tests. The static experimental test results emphasize that the SFRC beam has attained a higher ultimate load compared with the control RC beam.
33
Yang, Qing Guo, Yu Wei Zhang, and Zhi Zhong Tu. "The Study about Flexural Performance of GFRP Bar Reinforced Concrete Beams Based on Numerical Calculation Method." Applied Mechanics and Materials 29-32 (August 2010): 1350–56. http://dx.doi.org/10.4028/www.scientific.net/amm.29-32.1350.
Full textAbstract:
Replacing the steel bar with GFRP (Glass Fiber Reinforced Plastics) bar can improve the durability of concrete structure in the corrosive environment. Different ratios of GFRP bar lead huge difference performance of GFRP reinforced concrete beams; therefore, to reduce the workload, it is very necessary to study GFRP reinforced concrete beams’ performance with suitable numerical calculation method. In the study, first, GFRP reinforced concrete beams’ mechanical behavior and failure characteristics were researched through the flexural experiments of GFRP reinforced concrete beams with different ratio of GFRP bar; Second, the numerical calculation model of GFRP reinforced concrete beams was built according to experimental results which contain the load-displacement curve and the phenomenon that concrete in compression zone are crushed, then the calculation criterion of obtaining the beam’s bearing capacity was proposed. Lastly, the bending bearing capacity of GFRP bar reinforced concrete beams with different ratio of GFRP is obtained through the finite element calculation, and the practical and simple calculation formula is acquired.
34
Jing, Hang, and Yong Quan Li. "Nonlinear Finite Element Analysis of Layered Steel Fiber Reinforced Concrete Beam." Applied Mechanics and Materials 166-169 (May 2012): 616–19. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.616.
Full textAbstract:
A simplified finite element model for analysis of the Layered steel fiber beams with the concrete damaged plasticity model has been presented. The numerical simulation of load-deflection curve of layered steel fiber reinforced concrete beam under three-point loads is performed using ABAQUS. The results of simulation are generally in conformance with the experiment. The results of numerical simulation show that layered steel fiber has little contribution to the elastic capacity of concrete beam. But it can improve the ultimate bearing capacity of concrete beam obviously. The bending collapse style of layered steel fiber reinforced concrete beam is different from plain concrete beam evidently with obvious ductile characteristic.
35
Shuai, Tian, and Zhang Tong. "Study on Thermal Stress of Concrete Beams with Carbon-Fiber- Reinforced Polymers at Low Temperature." Open Construction and Building Technology Journal 8, no. 1 (2014): 182–92. http://dx.doi.org/10.2174/1874836801408010182.
Full textAbstract:
Concrete beams reinforced with carbon-fiber-reinforced polymers (CFRPs) are subjected to considerable thermal stress at low temperatures. To mitigate this problem, this study conducts a series of tests on three concrete specimens at various temperatures, analyzes the change rule of thermal stress in CFRP-reinforced concrete beams, and discusses the influence of CFRPs on thermal stress in terms of the elastic modulus, thickness, thermal expansion coefficient, beam height, and concrete grade. The results show that when the temperature decreases, CFRP has an obvious restraining effect on the thermal curve of concrete beams. The thermal stress on the interface of CFRP-reinforced concrete beams is sufficiently large and should not be ignored. In particular, in cold areas, thermal stress should be taken into account when reinforcing structures such as concrete bridges. The CFRP sheet’s elasticity modulus and thickness are the main factors affecting the thermal stress; in comparison, the expansion coefficient and beam height have lesser effect on the thermal stress; finally, the concrete grade has little effect on the thermal stress. Thermal stress can be prevented feasibly by using prestressed CFRP sheets to reinforce concrete beams. This study can serve as a reference for concrete reinforcement design.
36
Marčiukaitis, Gediminas, Mykolas Daugevičius, and Juozas Valivonis. "THE FRAGMENTATION OF THE TENSIONED ZONE OF THE STRENGTHENED REINFORCED CONCRETE BEAM WITH CARBON FIBER COMPOSITE." Engineering Structures and Technologies 2, no. 4 (2010): 129–37. http://dx.doi.org/10.3846/skt.2010.17.
Full textAbstract:
The article analyzes the intensification influence of tensioned concrete on carbon fiber composite and concrete joint in a strengthened beam cracking manner. The paper calculates enlarged concrete compressive tensioned strength according to the impregnation of epoxy resin. The article figures out the level of epoxy resin penetration and deals with a microscopic analysis of concrete and carbon fiber composite joint. The presented modified calculation method of the cracking moment evaluates the characteristics of impregnated modified tensioned concrete. Four beams were tested. Two reinforced concrete beams were additionally strengthened with an external carbon fiber composite layer and loaded till failure. In addition, two reinforced beams without external reinforcement were tested. The accomplished experimental research of cracking strengthened beams showed that the calculated cracking moments with evaluated tensioned concrete layer intensification were more similar than the results without evaluation. After failure of strengthened beams, accomplished microscopic analysisof debonded carbon fiber composite layer. A microscopic analysis of concrete and carbon fiber composite joint was performed applying electronic microscope DG-3x. The thickness of the composite layer and modified tensioned concrete layer was measured using Micro Measure V 1.0 computer program. The accomplished microscopic analysis approved theoretical assumptions about epoxy resin penetration and distribution between aggregates. The strengthening of the reinforced concrete beam with carbon fiber composite improved mechanical characteristics of the tensioned concrete layer near concrete and carbon fiber composite joint. During strengthening, epoxy resin penetrates into concrete and fills micro cracks and pores. Thus, epoxy resin provides additional connections with aggregates. The calculated modified concrete tensioned strength and modulus of elasticity was respectively 3,0 and 1,9 times higher than that of ordinary concrete. Changes in concrete strength at the tensioned layer have influence on cracking manner because the ultimate deformation of modified concrete increases. Experimentally determined what evolution of vertical crack starts above the modified tensioned concrete layer at the joint with carbon fiber composite. Peeling the carbon fiber composite layer when the ultimate load level is reached also evolves above the modified tensioned concrete layer. The remained hydrated cement on the surface of the peeled external composite layer proves that shear stresses in the joint of concrete and carbon fiber composite reduced a weaker tensioned layer of concrete.
37
Mohamed, Osama Ahmed, and Rania Khattab. "Numerical Analysis of Reinforced Concrete Beam Strengthened with CFRP or GFRP Laminates." Key Engineering Materials 707 (September 2016): 51–59. http://dx.doi.org/10.4028/www.scientific.net/kem.707.51.
Full textAbstract:
The behaviour of reinforced concrete beam strengthened with Carbon Fiber Reinforced Polymer (CFRP) and Glass fiber reinforced polymer GFRP laminates was investigated using finite element models and the results are presented in this paper. The numerical investigation assessed the effect of the configuration of FRP strengthening laminates on the behaviour of concrete beams. The load-deflection behaviour, and ultimate load of strengthened beam were compared to those of un-strengthened concrete beams. It was shown that using U-shaped FRP sheets increased the ultimate load. The stiffness of the strengthed beam also increased after first yielding of steel reinforcing bars. At was also observed that strengthening beams with FRP laminates to one-fourth of the beam span, modifies the failure of the beam from shear-controlled near the end of the unstrengthened beam, to flexure-controlled near mid-span. CFRP produced better results compared GFRP in terms of the ability to enhance the behavior of strengthenened reinforced concrete beams.
38
Chen, Yung Tsang. "An Experimental Study on the use of Fiber-Reinforced Concrete in Bridge Approach Slabs." Applied Mechanics and Materials 361-363 (August 2013): 1217–22. http://dx.doi.org/10.4028/www.scientific.net/amm.361-363.1217.
Full textAbstract:
Fiber-reinforced concrete is well known for crack control by bridging cracks in the concrete. Short, discontinuous fibers are added into plain concrete to provide post-cracking ductility to the fiber-reinforced concrete. Although fiber-reinforced concrete has been used in various civil engineering applications, the practical application of fiber-reinforced concrete in bridge approach slabs is rarely found. In this paper, steel fibers, serving as macro-fibers, and polyvinyl alcohol fibers, serving as micro-fibers, were added to the approach slab concrete for crack control purpose. This paper describes flexural tests of four fiber-reinforced concrete beams and loading test of a full scale fiber-reinforced concrete approach slab. Results from the flexural beam test show that the addition of fibers greatly improves the fracture toughness of the concrete. Results from the loading test show that the overall performance of the slab is comparable to conventional reinforced concrete approach slabs, and the surface cracks on the slab due to negative moment can be adequately controlled by the addition of steel and polyvinyl alcohol fibers into concrete, even without top reinforcement mat.
39
Wang, Zuohu, Yuan Yao, Du Liu, Yuqiang Cui, and Weizhang Liao. "Shear behavior of concrete beams pre-stressed with carbon fiber reinforced polymer tendons." Advances in Mechanical Engineering 11, no. 1 (2019): 168781401881687. http://dx.doi.org/10.1177/1687814018816879.
Full textAbstract:
This article presents experimental and numerical studies on the shear behavior of reinforced concrete beams pre-stressed with carbon fiber reinforced polymer tendons. A total of 23 beams were tested to analyze the failure mode and shear performance of pre-stressed concrete beams. Experimental results revealed that there were two typical shear failure modes, that is, shear compression failure and inclined compression failure. Next, the experimental and numerical results were used to explore factors influencing the failure mode and the shear behavior of the concrete beams, including the type of pre-stressing tendons, stirrup ratio, shear span–depth ratio, number of pre-stressing tendons, and their initial pretension levels. It is demonstrated that shear span–depth ratio and stirrup ratio are the two main determinants of the failure mode and shear capacity of the concrete beams pre-stressed with carbon fiber reinforced polymer tendons. However, the bonding conditions of the pre-stressing carbon fiber reinforced polymer tendons have no significant effect on the shear capacity of the pre-stressed concrete beam.
40
Chen, Xu Jun, Xiao E. Zhu, and Zhong Yang. "Study on Cracking Load of Normal Section for Concrete Beams Strengthened with BFRP Sheet." Applied Mechanics and Materials 578-579 (July 2014): 1343–46. http://dx.doi.org/10.4028/www.scientific.net/amm.578-579.1343.
Full textAbstract:
Based on the calculation method of cracking load for reinforced concrete beam, the formula to calculate cracking load of normal section for concrete beams strengthened with BFRP sheet is established. The cracking load experiment of seven concrete beams strengthened with BFRP and three concrete beams strengthened with CFRP is conducted, and the results showed that fiber sheet layers and fiber sheet types have little effect on cracking load of concrete beams strengthened, the cracking load of beams strengthened mainly depends on the strength of concrete. The comparison between estimated values and test values of concrete beams strengthened indicates that the estimated values are slightly smaller, the formula can be used to calculate the cracking load of concrete beams strengthened.
41
Hameed, Ali Ammar, and Mohannad Husain Al-Sherrawi. "Influence of Steel Fiber on the Shear Strength of a Concrete Beam." Civil Engineering Journal 4, no. 7 (2018): 1501. http://dx.doi.org/10.28991/cej-0309190.
Full textAbstract:
The shear failure in a concrete beam is a brittle type of failure. The addition of steel fibers in a plain concrete mix helps to bridge and restrict the cracks formed in the brittle concrete under applied loads, and enhances the ductility of the concrete. In this research an attempt was made to investigate the behavior and the ultimate shear strength of hooked end steel fiber reinforced concrete beams without traditional shear reinforcement. Four simply-supported reinforced concrete beams with a shear span-to-depth ratio of about 3.0 were tested under two-point loading up to failure. Steel fibers volumetric fractions that used were 0.0, 0.5, 0.75 and 1.0%. Test results indicated that using 1.0% volume fraction of hooked steel fiber led to exclude shear failure and enhanced the use of steel fibers as shear reinforcement in concrete beams. The results also showed that a concrete beam with hooked steel fiber provided higher post-flexural-cracking stiffness, an increase in the shear capacity and energy absorption and an increase in the maximum concrete and steel reinforcement strains.
42
Martínez-Ibernón, Ana, Marta Roig-Flores, Josep Lliso-Ferrando, Eduardo J. Mezquida-Alcaraz, Manuel Valcuende, and Pedro Serna. "Influence of Cracking on Oxygen Transport in UHPFRC Using Stainless Steel Sensors." Applied Sciences 10, no. 1 (2019): 239. http://dx.doi.org/10.3390/app10010239.
Full textAbstract:
Reinforced concrete elements frequently suffer small cracks that are not relevant from the mechanical point of view, but they can be an entrance point for aggressive agents, such as oxygen, which could initiate the degradation processes. Fiber-Reinforced Concrete and especially Ultra High Performance Concrete increase the multi-cracking behavior, reducing the crack width and spacing. In this work, the oxygen availability of three types of concrete was compared at similar strain levels to evaluate the benefit of multi-cracking in the transport of oxygen. The types of concrete studied include traditional, High-Performance, and Ultra-High-Performance Fiber-Reinforced Concrete with and without nanofibers. To this purpose, reinforced concrete beams sized 150 × 100 × 750 mm3 were prepared with embedded stainless steel sensors that were located at three heights, which have also been validated through this work. These beams were pre-cracked in bending up to fixed strain levels. The results indicate that the sensors used were able to detect oxygen availability due to the presence of cracks and the detected differences between the studied concretes. Ultra High Performance Concrete in the cracked state displayed lower oxygen availability than the uncracked High Performance Concrete, demonstrating its potential higher durability, even when working in cracked state, thanks to the increased multi-cracking response.
43
Li, Chang Yong, Hui Yang, Yang Liu, and Ke Ke Gao. "Flexural Behavior of Reinforced Concrete Beams Superposing with Partial Steel Fiber Reinforced Full-Lightweight Concrete." Applied Mechanics and Materials 438-439 (October 2013): 800–803. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.800.
Full textAbstract:
To improve the flexural properties and lighten the weight of ordinary reinforced concrete beam (RCB), this paper develops a new type of superposed RCB in which the tensile zone was partially cast with the steel fiber reinforced full-lightweight concrete (SFRFLC). 10 beams with different height of SFRFLC were designed. Their flexural behaviors were measured including the concrete strain at mid-span cross section, the load vs deflection curve, the cracking load and the ultimate load. It may be concluded that the test beams damage in ductile, the concrete strains at mid-span cross section basically fit the assumption of plain cross section, the variations of load vs deflection curves are similar with obvious changes at the points of the cracking of concrete and the yield of tensile reinforcements, the cracking loads are almost equal, and the ultimate loads tends to decrease with the increasing height of SFRFLC. The SFRFLC and ordinary concrete work well together, the suitable height of SFRFLC is there should be further studied.
44
He, Hua Nan, and Wei Dong. "Study on Damaged Reinforced Concrete Beams Strengthened with Basalt Fiber Polymer Sheets." Advanced Materials Research 446-449 (January 2012): 2941–44. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.2941.
Full textAbstract:
In practical concrete structures, once reinforced concrete beams serve in case of over cracking or are even damaged due to sudden overloading, it is necessary to repair or strengthened the damaged members for purpose of restoring the structural capacities and keeping the structures working well. At present FRP strengthening technique is one of the most accepted methods available in civil engineering. This paper particularly presents a new FRP material，basal fiber, which is applied to strengthen flexural behaviors of reinforced concrete beams suffering from different amplitudes of cracking damage. Herein, total 4 reinforced concrete beams were tested including one reference beam and three beams strengthened with basalt fiber polymer sheets. The three strengthened beams were preloaded to an expected load and then strengthen by basalt fibers under loading. The test parameters are involved in different pre-loads and layers of basalt fiber sheets. During test some flexural behaviors were obtained in terms of variation of strain in concrete, steel bar and basalt fiber sheet, flexural deflection, collapse loads and the failure modes as well as cracking properties of R.C beams strengthened with basalt fiber sheets. The results of test indicated that flexural behaviors of the beams strengthened under loading with basalt fiber polymer could be improved in different degree with varied initial flexural moment and numbers of basalt fiber.
45
Lv, Yang, Xueqian Wu, Mengran Gao, et al. "Flexural Behavior of Basalt Fiber Reinforced Polymer Tube Confined Coconut Fiber Reinforced Concrete." Advances in Materials Science and Engineering 2019 (February 3, 2019): 1–7. http://dx.doi.org/10.1155/2019/1670478.
Full textAbstract:
Basalt fiber has arisen new perspectives due to the potential low cost and excellent mechanical performance, together with the use of environmental friendly coir can be beneficial to the development of sustainable construction. In this study, a new composite structure called basalt fiber reinforced polymer (BFRP) tube encased coconut fiber reinforced concrete (CFRC) is developed. The 28-day compression strength of the plain concrete is about 15 MPa, which represents the low-strength poor-quality concrete widely existing in many old buildings and developing countries. Three types of BFRP tubes, i.e., 2-layer, 4-layer, and 6-layer, with the inner diameter of 100 mm and a length of 520 mm, were prepared. The plain concrete (PC) and CFRC were poured and cured in these tubes to fabricated BFRP tube confined long cylindrical beams. Three PC cylindrical beams and 3 CFRC cylindrical beams were prepared to be the control group. The four-point bending tests of these specimens were carried out to investigate the enhancement due to the BFRP tube and coir reinforcement. The load-carrying capacity, force-displacement relationship, failure mode, and the cracking moment were analyzed. Results show that both BFRP tube confined plain concrete (PC) and BFRP tube confined CFRC have excellent flexural strength and ductility, and the inclusion of the coir can further enhance the ductility of the concrete.
46
Abdulhameed, Ali Adel, and AbdulMuttalib Issa Said. "Behaviour of Segmental Concrete Beams Reinforced by Pultruded CFRP Plates: An Experimental Study." Journal of Engineering 25, no. 8 (2019): 62–79. http://dx.doi.org/10.31026/j.eng.2019.08.05.
Full textAbstract:
The research aims to develop an innovative technique for segmental beam fabrication using plain concrete blocks and externally bonded Carbon Fiber Reinforced Polymers Laminates (CFRP) as a main flexural reinforcement. Six beams designed and tested under two-point loadings. Several parameters included in the fabrication of segmental beam were studied such as; bonding length of carbon fiber reinforced polymers, the surface-to-surface condition of concrete segments, interface condition of the bonding surface and thickness of epoxy resin layers. Test results of the segmental beams specimens compared with that gained from testing reinforced concrete beam have similar dimensions for validations. The results display the effectiveness of the developed fabrication method of segmental beams. The modified design procedure for externally bonded carbon fiber reinforced polymers ACI 440.2R-17 was developed for designing segmental beams. The experimental test values also compared with design values, and it was 93.3% and 105.8% of the design values, which indicates the effectiveness of the developed procedure.
47
Abdulhameed, Ali A., and AbdulMuttalib Issa Said. "Behaviour of Segmental Concrete Beams Reinforced by Pultruded CFRP Plates: an Experimental Study." Journal of Engineering 25, no. 8 (2019): 62–79. http://dx.doi.org/10.31026/j.eng.2019.08.11.
Full textAbstract:
Research aims to develop a novel technique for segmental beam fabrication using plain concrete blocks and externally bonded Carbon Fiber Reinforced Polymers Laminates (CFRP) as a main flexural reinforcement. Six beams designed an experimentally tested under two-point loadings. Several parameters included in the fabrication of segmental beam studied such as; bonding length of carbon fiber reinforced polymers, the surface-to-surface condition of concrete segments, interface condition of the bonding surface, and thickness of epoxy resin layers. Test results of the segmental beams specimens compared with that gained from testing reinforced concrete beam have similar dimensions for validations. The results show the effectiveness of the developed fabrication method of segmental beams. The modified design procedure for externally bonded carbon fiber reinforced polymers ACI 440.2R-17 developed for designing segmental beams. The experimental test values also compared with design values and it was 93.3% and 105.8% of the design values which indicates the effectiveness of the developed procedure.
48
Dong, Jiang Feng, Qing Yuan Wang, Ci Chang Qiu, and Dong He. "Experimental Study on RC Beams Strengthened with CFRP Sheets." Advanced Materials Research 213 (February 2011): 548–52. http://dx.doi.org/10.4028/www.scientific.net/amr.213.548.
Full textAbstract:
This paper presents the flexural performance of reinforced concrete (RC) beams with rectangular section. Seven RC beams strengthened using carbon fiber reinforced polymer (CFRP) sheets were subjected to four-point bending to investigate the effect of fiber reinforcement on the beams strengthened. The main experimental parameters included in the study are the pre-cracked width, CFRP sheet layers, the longitudinal tensile reinforcement ratio, the shear span ratio, and the concrete cover thickness. In total, seven beams were cast, one beam without any reinforcement as a control beam, two beams strengthened by CFRP sheets without making pre-cracks on the beam and four pre-cracked beams repaired with one layer or two layers CFRP sheets. Test results show the effectiveness and flexural capacity of the CFRP strengthened beams. The flexure enhancement of the CFRP strengthened beams varied between 41.7% and 124.1% over the control beam. This study confirms that the CFRP reinforcing technique significantly enhances the flexural capacity of reinforced concrete beams.
49
Torres, Juan Andres, and Eva O. L. Lantsoght. "Influence of Fiber Content on Shear Capacity of Steel Fiber-Reinforced Concrete Beams." Fibers 7, no. 12 (2019): 102. http://dx.doi.org/10.3390/fib7120102.
Full textAbstract:
For shear-critical structural elements where the use of stirrups is not desirable, such as slabs or beams with reinforcement congestion, steel fibers can be used as shear reinforcement. The contribution of the steel fibers to the shear capacity lies in the action of the steel fibers bridging the shear crack, which increases the shear capacity and prevents a brittle failure mode. This study evaluates the effect of the amount of fibers in a concrete mix on the shear capacity of steel fiber-reinforced concrete beams with mild steel tension reinforcement and without stirrups. For this purpose, 10 beams were tested. Five different fiber volume fractions were studied: 0.0%, 0.3%, 0.6%, 0.9%, and 1.2%. For each different steel fiber concrete mix, the concrete compressive strength was determined on cylinders and the tensile strength was determined in a flexural test on beam specimens. Additionally, the influence of fibers on the shear capacity was analyzed based on results reported in the literature, as well as based on the expressions derived for estimating the shear capacity of steel fiber-reinforced concrete beams. The outcome of these experiments is that a fiber percentage of 1.2% or fiber factor of 0.96 can be used to replace minimum stirrups according to ACI 318-14 and a 0.6% fiber volume fraction or fiber factor of 0.48 to replace minimum stirrups according to Eurocode 2. A fiber percentage of 1.2% or fiber factor of 0.96 was observed to change the failure mode from shear failure to flexural failure. The results of this study support the inclusion of provisions for steel fiber-reinforced concrete in building codes and provides recommendations for inclusion in ACI 318-14 and Eurocode 2, so that a wider adoption of steel fiber reinforced concrete can be achieved in the construction industry.
50
Ghoneim, Mohamed, Ayatollah Yehia, Sherif Yehia, and Wael Abuzaid. "Shear Strength of Fiber Reinforced Recycled Aggregate Concrete." Materials 13, no. 18 (2020): 4183. http://dx.doi.org/10.3390/ma13184183.
Full textAbstract:
In this paper, shear strength of fiber reinforced recycled concrete was investigated. A Self Consolidated Concrete (SCC) matrix with 100% coarse recycled aggregate and different types of fibers were used in the study. Steel (3D and 5D), synthetic and hybrid fibers with a volume fraction of 0.75% were added to the concrete matrix to prepare eight beams. In addition, two beams were cast without fibers as control specimens. All beams were prepared without shear reinforcement and were tested to evaluate concrete contribution to the shear capacity. In addition, optical images were captured to allow for full-field displacement measurements using Digital Image Correlation (DIC). The results showed about 23.44–64.48% improvement in the average concrete shear capacity for fiber-reinforced beams when compared to that of the control specimens. The percentage improvement was affected by fiber type and the steel fiber beams achieved the best performance. The addition of the fiber delayed the crack initiation and improved the post-cracking and ductile behavior of all beams. Moreover, the experimental results were compared to those predicted by codes and proposed equations found in the literature for concrete strength with and without fibers.