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Volume 6
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Fibers, Volume 6, Issue 1 (March 2018) – 17 articles

Cover Story (view full-size image): The apparent shear strength at the interface between a bamboo fiber and a PLA matrix is quantified. A method for processing pull-out test samples within a controlled embedded length is proposed and the test procedure is presented, along with a critical discussion of the results. Untreated and mercerized bamboo fibers, from the same batch and embedded in the same matrix, are compared. The fiber–matrix interface before and after the test is observed to identify the failure mode of each sample, especially as regards the occurrence of fibrillation in the fiber bundles. View the paper here.
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18 pages, 7149 KiB  
Article
Dynamic In-Situ Observation on the Failure Mechanism of Flax Fiber through Scanning Electron Microscopy
by Shabbir Ahmed and Chad A. Ulven
Fibers 2018, 6(1), 17; https://doi.org/10.3390/fib6010017 - 19 Mar 2018
Cited by 23 | Viewed by 10116
Abstract
In order to develop and improve bio-inspired fibers, it is necessary to have a proper understanding of the fracture behavior of bio-fibers such as flax fibers from an individual fiber down to the constituent micro-fibrils and nano-fibrils. For investigating the failure mechanism of [...] Read more.
In order to develop and improve bio-inspired fibers, it is necessary to have a proper understanding of the fracture behavior of bio-fibers such as flax fibers from an individual fiber down to the constituent micro-fibrils and nano-fibrils. For investigating the failure mechanism of individual and technical flax fibers, a tensile test bench was placed within a scanning electron microscope, and the entire process of fiber failure was investigated through the capture of an SEM movie. Next, fractographic analysis was performed on the failure surface of single fibers as well as meso-fibrils that failed at a displacement rate of 0.25 mm/min, 0.75 mm/min, and 1.6 mm/min. The analysis also enabled visualization of a few internal details of flax fiber such as the arrangement of meso-fibrils and micro-fibrils (nano-fibrils). It was shown that the crack bridging mechanism and successive fiber pull-out contributed to the high work of fracture of flax fiber and the value may reach as high as 10 6 J / m 2 . Full article
(This article belongs to the Special Issue Plant Bast Fibers)
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12 pages, 4221 KiB  
Article
Investigation of Transcrystalline Interphases in Polypropylene/Glass Fiber Composites Using Micromechanical Tests
by Hanna Brodowsky and Edith Mäder
Fibers 2018, 6(1), 16; https://doi.org/10.3390/fib6010016 - 12 Mar 2018
Cited by 8 | Viewed by 6196
Abstract
In composites, a strong interphase between the components is essential for mechanical properties. By using a suitable sizing (i.e., surface modification) of the fiber, the interphase may be varied, e.g., by suppressing or promoting heterogeneous nucleation of a thermoplastic matrix. In the latter [...] Read more.
In composites, a strong interphase between the components is essential for mechanical properties. By using a suitable sizing (i.e., surface modification) of the fiber, the interphase may be varied, e.g., by suppressing or promoting heterogeneous nucleation of a thermoplastic matrix. In the latter case, three-dimensional transcrystallized interphases with properties differing from those of the bulk matrix are formed. Polypropylene-glass fiber composites are prepared as single-fiber model composites with (a) sizings either inducing or suppressing a transcrystalline interphase, (b) different amounts of modifier maleic acid anhydride grafted polypropylene, and (c) different molecular weights of the matrix polymer. These are studied in quasi-static or cyclic load tests. Static tests permit insights in the interfacial characteristics such as critical interface energy release rate, adhesion strength and frictional stress. Cyclic tests on these model composites can be used to study the nature of dissipative processes and the damage behavior. Atomic Force Microscopy (AFM) investigations of the fiber fracture surfaces provide supplementary information. The transcrystalline layer can indeed improve the mechanical parameters (a 70–100% increase of strength and a 25 or 125% increase in toughness, depending on the molecular weight (MW) of the matrix polymer at low modifier concentration). However, the effect is partially neutralized by an opposing effect: high nucleation in the bulk in samples with commonly used concentrations of modifier. Full article
(This article belongs to the Special Issue Glass Fibers 2018)
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19 pages, 11998 KiB  
Review
Synthetic Strategies for the Fabrication of Cationic Surface-Modified Cellulose Nanocrystals
by Rajesh Sunasee and Usha D. Hemraz
Fibers 2018, 6(1), 15; https://doi.org/10.3390/fib6010015 - 5 Mar 2018
Cited by 38 | Viewed by 12496
Abstract
Cellulose nanocrystals (CNCs) are renewable nanosized materials with exceptional physicochemical properties that continue to garner a high level of attention in both industry and academia for their potential high-end material applications. These rod-shaped CNCs are appealing due to their non-toxic, carbohydrate-based chemical structure, [...] Read more.
Cellulose nanocrystals (CNCs) are renewable nanosized materials with exceptional physicochemical properties that continue to garner a high level of attention in both industry and academia for their potential high-end material applications. These rod-shaped CNCs are appealing due to their non-toxic, carbohydrate-based chemical structure, large surface area, and the presence of ample surface hydroxyl groups for chemical surface modifications. CNCs, generally prepared from sulfuric acid-mediated hydrolysis of native cellulose, display an anionic surface that has been exploited for a number of applications. However, several recent studies showed the importance of CNCs’ surface charge reversal towards the design of functional cationic CNCs. Cationization of CNCs could further open up other innovative applications, in particular, bioapplications such as gene and drug delivery, vaccine adjuvants, and tissue engineering. This mini-review focuses mainly on the recent covalent synthetic methods for the design and fabrication of cationic CNCs as well as their potential bioapplications. Full article
(This article belongs to the Special Issue Current Developments in Cellulose Based Nanomaterials)
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18 pages, 18374 KiB  
Article
Use of a Simple Non-Destructive Technique for Evaluation of the Elastic and Vibration Properties of Fiber-Reinforced and 3D Fiber-Metal Laminate Composites
by Davide De Cicco and Farid Taheri
Fibers 2018, 6(1), 14; https://doi.org/10.3390/fib6010014 - 2 Mar 2018
Cited by 9 | Viewed by 6812
Abstract
The aim of this paper is to assess the accuracy and reliability of a simple non-destructive sonic technique for evaluating the effective elastic and vibration properties (damping coefficient) of various isotropic and orthotropic materials—in particular, of a recently developed class of 3D fiber-metal [...] Read more.
The aim of this paper is to assess the accuracy and reliability of a simple non-destructive sonic technique for evaluating the effective elastic and vibration properties (damping coefficient) of various isotropic and orthotropic materials—in particular, of a recently developed class of 3D fiber-metal laminates (FML). Aluminum, E-glass/epoxy composite, 3D-FML, and glass-reinforced aluminum FML (GLARE) materials were considered. It is exhibited that the 3D-FML offers the greatest damping characteristics in comparison to all the considered materials. Moreover, the sonic technique, facilitated through the use of a GrindoSonic equipment, proves to produce accurate and reliable results with minimal effort. Finite element analysis is also employed to further establish the accuracy of the properties evaluated by the experimental data. The utility of the established homogenized experimental properties within the finite element framework is also discussed. Full article
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13 pages, 7356 KiB  
Review
Advances on Polymer Optical Fiber Gratings Using a KrF Pulsed Laser System Operating at 248 nm
by Carlos A. F. Marques, Arnaldo G. Leal-Junior, Rui Min, Maria Domingues, Cátia Leitão, Paulo Antunes, Beatriz Ortega and Paulo André
Fibers 2018, 6(1), 13; https://doi.org/10.3390/fib6010013 - 1 Mar 2018
Cited by 68 | Viewed by 6519
Abstract
This paper presents the achievements and progress made on the polymer optical fiber (POF) gratings inscription in different types of Fiber Bragg Gratings (FBGs) and long period gratings (LPGs). Since the first demonstration of POFBGs in 1999, significant progress has been made where [...] Read more.
This paper presents the achievements and progress made on the polymer optical fiber (POF) gratings inscription in different types of Fiber Bragg Gratings (FBGs) and long period gratings (LPGs). Since the first demonstration of POFBGs in 1999, significant progress has been made where the inscription times that were higher than 1 h have been reduced to 15 ns with the application of the krypton fluoride (KrF) pulsed laser operating at 248 nm and thermal treatments such as the pre-annealing of fibers. In addition, the application of dopants such as benzyl dimethyl ketal (BDK) has provided a significant decrease of the fiber inscription time. Furthermore, such improvements lead to the possibility of inscribing POF gratings in 850 nm and 600 nm, instead of only the 1550 nm region. The progress on the inscription of different types of polymer optical fiber Bragg gratings (POFBGs) such as chirped POFBGs and phase-shifted POFBGs are also reported in this review. Full article
(This article belongs to the Special Issue Optical Fiber Communications)
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13 pages, 7458 KiB  
Article
Restrained Shrinkage Cracking of Fiber-Reinforced High-Strength Concrete
by Ashkan Saradar, Behzad Tahmouresi, Ehsan Mohseni and Ali Shadmani
Fibers 2018, 6(1), 12; https://doi.org/10.3390/fib6010012 - 19 Feb 2018
Cited by 76 | Viewed by 10417
Abstract
Concrete shrinkage and volume reduction happens due to the loss of moisture, which eventually results in cracks and more concrete deformation. In this study, the effect of polypropylene (PP), steel, glass, basalt, and polyolefin fibers on compressive and flexural strength, drying shrinkage, and [...] Read more.
Concrete shrinkage and volume reduction happens due to the loss of moisture, which eventually results in cracks and more concrete deformation. In this study, the effect of polypropylene (PP), steel, glass, basalt, and polyolefin fibers on compressive and flexural strength, drying shrinkage, and cracking potential, using the ring test at early ages of high-strength concrete mixtures, was investigated. The restrained shrinkage test was performed on concrete ring specimens according to the ASTM C1581 standard. The crack width and age of restrained shrinkage cracking were the main parameters studied in this research. The results indicated that the addition of fiber increases the compressive strength by 16%, 20%, and 3% at the age of 3, 7, and 28 days, respectively, and increases the flexural toughness index up to 7.7 times. Steel and glass fibers had a better performance in flexural strength, but relatively poor action in the velocity reduction and cracking time of the restrained shrinkage. Additionally, cracks in all concrete ring specimens except for the polypropylene-containing mixture, was developed to a full depth crack. The mixture with polypropylene fiber indicated a reduction in crack width up to 62% and an increasing age cracking up to 84%. Full article
(This article belongs to the Special Issue Recent Advancements in Fiber Reinforced Concrete And its Applications)
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12 pages, 2166 KiB  
Article
Structural Evolution of Gossypium hirsutum Fibers Grown under Greenhouse and Hydroponic Conditions
by Filipe Natalio and Raquel Maria
Fibers 2018, 6(1), 11; https://doi.org/10.3390/fib6010011 - 12 Feb 2018
Cited by 6 | Viewed by 8130
Abstract
Cotton is the leading fiber source in the textile industry and one of the world’s most important crops. Despite its economic interest, cotton culture exerts an enormous pressure on natural resources (land and water) and has a negative impact on the environment (abuse [...] Read more.
Cotton is the leading fiber source in the textile industry and one of the world’s most important crops. Despite its economic interest, cotton culture exerts an enormous pressure on natural resources (land and water) and has a negative impact on the environment (abuse of pesticides). Thus, alternative cotton growing methods are urged to be implemented. Recently, we have demonstrated that Gossypium hirsutum (“Upland” cotton) can be grown in a greenhouse (controlled conditions) and hydroponically. Here we report on the elucidation of the structural changes of the Gossypium hirsutum fibers during maturation grown [10, 14, 17, 20, 36 and 51 days post anthesis (dpa)] under a greenhouse and hydroponically, by means of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy with attenuated total reflectance (FT-IR ATR) and thermal gravimetric analysis/differential scanning calorimetry (TGA/DSC). The transition from primary to secondary cell wall growth occurs between 17 and 20 dpa—similarly to the soil-based cultures. However, this new cotton culture offers an advantageous pesticide and soil-free all year-round closed system with efficient water use yielding standardized mature fibers with improved properties (maturity, strength, length, whiteness). Full article
(This article belongs to the Special Issue Natural Fibers)
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16 pages, 2164 KiB  
Article
Influence of Stem Diameter on Fiber Diameter and the Mechanical Properties of Technical Flax Fibers from Linseed Flax
by Mercedes Alcock, Shabbir Ahmed, Shawna DuCharme and Chad A. Ulven
Fibers 2018, 6(1), 10; https://doi.org/10.3390/fib6010010 - 5 Feb 2018
Cited by 14 | Viewed by 7349
Abstract
The continued search for sustainable and eco-friendly materials has led to the integration of bio-fibers, such as flax fiber, as reinforcement in composite materials; however, a wide variation in their diameters and mechanical properties poses a considerable challenge for their incorporation in load [...] Read more.
The continued search for sustainable and eco-friendly materials has led to the integration of bio-fibers, such as flax fiber, as reinforcement in composite materials; however, a wide variation in their diameters and mechanical properties poses a considerable challenge for their incorporation in load bearing and structural bio-composite materials. In this paper, a rigorous experimental investigation was performed using two varieties of linseed flax from two growing locations to determine if the variations observed in ultimate tensile strength, Young’s modulus, failure strain and diameter could be attributed to the diameters of the stems that produced the fibers. Tests were performed in two different facilities and the results were compared and analyzed using Welch’s t-tests. Results showed that samples which differed by stem diameter had statistically significant positive correlation with fiber diameter and negative correlation with tensile strength. No correlations for tensile strength, Young’s modulus or fiber diameter were found in samples with the same stem diameter range that were grown in different locations or were of different varieties, that is the effect of location and variety is not statistically significant. Failure strain did not show any statistical significance with respect to differences in stem diameter and only showed one statistically significant result between both facilities for one of the two growing location comparisons. Full article
(This article belongs to the Special Issue Plant Bast Fibers)
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17 pages, 16052 KiB  
Article
Effect of Polypropylene Fibers on Self-Healing and Dynamic Modulus of Elasticity Recovery of Fiber Reinforced Concrete
by Adham El-Newihy, Pejman Azarsa, Rishi Gupta and Alireza Biparva
Fibers 2018, 6(1), 9; https://doi.org/10.3390/fib6010009 - 1 Feb 2018
Cited by 34 | Viewed by 8843
Abstract
This study aims to evaluate self-healing properties and recovered dynamic moduli of engineered polypropylene fiber reinforced concrete using non-destructive resonant frequency testing. Two types of polypropylene fibers (0.3% micro and 0.6% macro) and two curing conditions have been investigated: Water curing (at ~25 [...] Read more.
This study aims to evaluate self-healing properties and recovered dynamic moduli of engineered polypropylene fiber reinforced concrete using non-destructive resonant frequency testing. Two types of polypropylene fibers (0.3% micro and 0.6% macro) and two curing conditions have been investigated: Water curing (at ~25 Celsius) and air curing. The Impact Resonance Method (IRM) has been conducted in both transverse and longitudinal modes on concrete cylinders prior/post crack induction and post healing of cracks. Specimens were pre-cracked at 14 days, obtaining values of crack width in the range of 0.10–0.50 mm. Addition of polypropylene fibers improved the dynamic response of concrete post-cracking by maintaining a fraction of the original resonant frequency and elastic properties. Macro fibers showed better improvement in crack bridging while micro fiber showed a significant recovery of the elastic properties. The results also indicated that air-cured Polypropylene Fiber Reinforced Concrete (PFRC) cylinders produced ~300 Hz lower resonant frequencies when compared to water-cured cylinders. The analyses showed that those specimens with micro fibers exhibited a higher recovery of dynamic elastic moduli. Full article
(This article belongs to the Special Issue Fibers and Techniques for Upgrading of Concrete and Masonry Constructions)
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6 pages, 4269 KiB  
Brief Report
Transcriptome Assembly of the Bast Fiber Crop, Ramie, Boehmeria nivea (L.) Gaud. (Urticaceae)
by Louay Al-Ani and Michael K. Deyholos
Fibers 2018, 6(1), 8; https://doi.org/10.3390/fib6010008 - 1 Feb 2018
Cited by 3 | Viewed by 5551
Abstract
Ramie (Boehmeria nivea) is a perennial crop valued for its strong bast fibers. Unlike other major bast fiber crops, ramie fiber processing does not include retting, but does require degumming, suggesting distinctive features in pectin and the development and composition of [...] Read more.
Ramie (Boehmeria nivea) is a perennial crop valued for its strong bast fibers. Unlike other major bast fiber crops, ramie fiber processing does not include retting, but does require degumming, suggesting distinctive features in pectin and the development and composition of fibers. A comprehensive transcriptome assembly of ramie has not been made available, to date. We obtained the sequence of RNA transcripts (RNA Seq) from the apical region of developing ramie stems and combined these with reads from public databases for a total of 157,621,051 paired-end reads (30.3 billion base pairs Gbp) used as input for de novo assembly, resulting in 70,721 scaffolds (≥200 base pairs (bp); N50 = 1798 bp). As evidence of the quality of the assembly, 36,535 scaffolds aligned to at least one Arabidopsis protein (BLASTP e-value ≤ 10−10). The resource described here for B. nivea will facilitate an improved understanding of bast fibers, cell wall, and middle lamella development in this and other comparative species. Full article
(This article belongs to the Special Issue Plant Bast Fibers)
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15 pages, 3359 KiB  
Article
Interfacial Characterization by Pull-Out Test of Bamboo Fibers Embedded in Poly(Lactic Acid)
by Quentin Viel, Antonella Esposito, Jean-Marc Saiter, Carlo Santulli and Joseph A. Turner
Fibers 2018, 6(1), 7; https://doi.org/10.3390/fib6010007 - 19 Jan 2018
Cited by 36 | Viewed by 7380
Abstract
In this work, the apparent shear strength at the interface between a bamboo fiber and the surrounding poly(lactic acid) (PLA) matrix is quantified. A method for processing pull-out test samples within a controlled embedded length is proposed and the details of the test [...] Read more.
In this work, the apparent shear strength at the interface between a bamboo fiber and the surrounding poly(lactic acid) (PLA) matrix is quantified. A method for processing pull-out test samples within a controlled embedded length is proposed and the details of the test procedure are presented, along with a critical discussion of the results. Two series of samples are considered: untreated and mercerized bamboo fibers from the same batch, embedded in the same polyester matrix. Electron and optical microscopy are used to observe the fiber–matrix interface before and after the test, and to identify the failure mode of each sample, especially as regards the occurrence of fibrillation in the fiber bundles. The values of apparent interfacial shear strength are calculated only for regular fibers successfully pulled out from the matrix, and reported with their statistical variations. Mercerization, whose efficiency was proven by Fourier transform infrared (FTIR) spectroscopy, did not appear though to improve the quality of the interface (τapp = 7.0 ± 3.1 MPa for untreated fibers and τapp = 5.3 ± 2.4 MPa for treated fibers). Full article
(This article belongs to the Special Issue Plant Bast Fibers)
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9 pages, 2113 KiB  
Communication
Investigation of the Mechanical Properties of Flax Cell Walls during Plant Development: The Relation between Performance and Cell Wall Structure
by Camille Goudenhooft, David Siniscalco, Olivier Arnould, Alain Bourmaud, Olivier Sire, Tatyana Gorshkova and Christophe Baley
Fibers 2018, 6(1), 6; https://doi.org/10.3390/fib6010006 - 17 Jan 2018
Cited by 47 | Viewed by 8102
Abstract
The development of flax (Linum usitatissimum L.) fibers was studied to obtain better insight on the progression of their high mechanical performances during plant growth. Fibers at two steps of plant development were studied, namely the end of the fast growth period [...] Read more.
The development of flax (Linum usitatissimum L.) fibers was studied to obtain better insight on the progression of their high mechanical performances during plant growth. Fibers at two steps of plant development were studied, namely the end of the fast growth period and at plant maturity, each time at three plant heights. The indentation modulus of the fiber cell wall was characterized by atomic force microscopy (AFM) using peak-force quantitative nano-mechanical property mapping (PF-QNM). Changes in the cell wall modulus with the cell wall thickening were highlighted. For growing plants, fibers from top and middle heights show a loose inner Gn layer with a lower indentation modulus than mature fibers, which exhibit thickened homogeneous cell walls made only of a G layer. The influence of these changes in the fiber cell wall on the mechanical performances of extracted elementary fibers was also emphasized by tensile tests. In addition, Raman spectra were recorded on samples from both growing and mature plants. The results suggest that, for the fiber cell wall, the cellulose contribution increases with fiber maturity, leading to a greater cell wall modulus of flax fibers. Full article
(This article belongs to the Special Issue Plant Bast Fibers)
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2 pages, 155 KiB  
Editorial
Acknowledgement to Reviewers of Fibers in 2017
by Fibers Editorial Office
Fibers 2018, 6(1), 5; https://doi.org/10.3390/fib6010005 - 12 Jan 2018
Viewed by 4072
Abstract
Peer review is an essential part in the publication process, ensuring that Fibers maintains high quality standards for its published papers[...] Full article
6 pages, 7655 KiB  
Article
The Fiber Connection Method Using a Tapered Silica Fiber Tip for Microstructured Polymer Optical Fibers
by Miguel Ferreira, André Gomes, Dominik Kowal, Gabriela Statkiewicz-Barabach, Pawel Mergo and Orlando Frazão
Fibers 2018, 6(1), 4; https://doi.org/10.3390/fib6010004 - 9 Jan 2018
Cited by 15 | Viewed by 5622
Abstract
In this work, an alternative method of coupling light into microstructured polymer fibers is presented. The solution consists in using a fiber taper fabricated with a CO2 laser. The connection is formed by inserting a tapered silica tip into the holes of [...] Read more.
In this work, an alternative method of coupling light into microstructured polymer fibers is presented. The solution consists in using a fiber taper fabricated with a CO2 laser. The connection is formed by inserting a tapered silica tip into the holes of a microstructured polymer fiber. This alternative method is duly characterized and the feasibility of such fiber connection to enable the polymer fiber as a displacement sensor is also demonstrated. Full article
(This article belongs to the Special Issue Fabrication of Special Optical Glass and Polymer Fibres)
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10 pages, 2949 KiB  
Article
Effect of Filler Orientation on the Electrical Conductivity of Carbon Fiber/PMMA Composites
by Muchao Qu, Fritjof Nilsson and Dirk W. Schubert
Fibers 2018, 6(1), 3; https://doi.org/10.3390/fib6010003 - 1 Jan 2018
Cited by 40 | Viewed by 9655
Abstract
The electrical conductivity of extruded carbon fiber (CF)/Polymethylmethacrylate (PMMA) composites with controlled CF aspect ratio and filler fractions ranging from 0 to 50 vol. % has been investigated and analyzed. The composites were extruded through a capillary rheometer, utilizing either 1-mm or 3-mm [...] Read more.
The electrical conductivity of extruded carbon fiber (CF)/Polymethylmethacrylate (PMMA) composites with controlled CF aspect ratio and filler fractions ranging from 0 to 50 vol. % has been investigated and analyzed. The composites were extruded through a capillary rheometer, utilizing either 1-mm or 3-mm diameter extrusion dies, resulting in cylindrical composite filaments of two different diameters. Since the average CF orientation becomes more aligned with the extrusion flow when the diameter of the extrusion dies decreases, the relationship between conductivity and average fiber orientation could therefore be examined. The room temperature conductivities of the extruded filaments as a function of CF fractions were fitted to the McLachlan general effective medium (GEM) equation and the percolation thresholds were determined to 20.0 ± 2.5 vol. % and 32.0 ± 5.9 vol. % for the 3-mm (with CFs oriented less) and 1-mm (with CFs oriented more) filaments, respectively. It turned out that the oriented CFs in the composite shift the percolation threshold to a higher value, however, the conductivity above the percolation threshold is higher for composites with oriented CFs. A novel approach based on the Balberg excluded volume theory was proposed to explain this counterintuitive phenomenon. Full article
(This article belongs to the Special Issue Carbon Fiber Reinforced Composites)
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10 pages, 3852 KiB  
Article
Flexural Behavior of Hybrid PVA Fiber and AR-Glass Textile Reinforced Geopolymer Composites
by Faiz Uddin Ahmed Shaikh and Aditya Patel
Fibers 2018, 6(1), 2; https://doi.org/10.3390/fib6010002 - 1 Jan 2018
Cited by 32 | Viewed by 8876
Abstract
Textile reinforced mortar or concrete, a thin cementitious composite reinforced by non-corrosive polymer textile fabric, was developed and has been researched for its role on repair and strengthening of reinforced concrete (RC) structures. Due to embedment of polymeric textile fabric inside the cementitious [...] Read more.
Textile reinforced mortar or concrete, a thin cementitious composite reinforced by non-corrosive polymer textile fabric, was developed and has been researched for its role on repair and strengthening of reinforced concrete (RC) structures. Due to embedment of polymeric textile fabric inside the cementitious matrix, many researchers argued the superiority of this technology than the externally bonded fiber reinforced polymer (FRP) sheet in RC in terms of prevention of debonding of FRP and durability in fire. However, due to use of cement rich matrix the existing development of textile reinforced concrete (TRC) need to be more environmental friendly by replacing cement based binder with geopolymeric binder. This paper presents a first study on the flexural behavior of alkali resistant glass fiber textile reinforced geopolymer (TRG). In this study, two types of geopolymer binder is considered. One is fly ash based heat cured geopolymer and the other is fly ash/slag blended ambient air cured geopolymer binder. Both geopolymer types are considered in the TRG and the results are benchmarked with the current cement based TRC. The effect of short polyvinyl alcohol (PVA) fiber as hybrid reinforced with alkali-resistant (AR) glass fiber textile on the flexural behavior of above TRC and TRGs is also studied. Results show deflection hardening behavior of both TRGs with higher flexural strength in heat cured TRG and higher deflection capacity at peak load in ambient air cured TRG. The increase in PVA fiber volume fraction from 1% to 1.5% did not show any improvement in flexural strength of both TRGs although TRC showed good improvement. In the case of deflection at peak load, an opposite phenomenon is observed where the deflection at peak load in both TRGs is increased due to increase in PVA fiber volume fractions. Full article
(This article belongs to the Special Issue Geopolymer Based Fiber Reinforced Composites)
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160 KiB  
Editorial
FRP for Infrastructure Applications: Research Advances
by Mahmoud Reda Taha
Fibers 2018, 6(1), 1; https://doi.org/10.3390/fib6010001 - 21 Dec 2017
Cited by 5 | Viewed by 4786
Abstract
n/a Full article
(This article belongs to the Special Issue Fiber Reinforced Polymers (FRP) for Infrastructure Applications)
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