Open AccessArticle
Performance of Strengthened Non-Uniformly Corroded Reinforced SCC-RAP Members
Fibers 2016, 4(4), 30; doi:10.3390/fib4040030 -
Abstract
This research examines the performance of strengthened non-uniformly corroded reinforced self-consolidating concrete (SCC) members. This paper focuses on three aspects of concrete including corrosion, concrete cover loss, and repair technique. Up to a 50% corrosion level is considered in this study. Corrosion was
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This research examines the performance of strengthened non-uniformly corroded reinforced self-consolidating concrete (SCC) members. This paper focuses on three aspects of concrete including corrosion, concrete cover loss, and repair technique. Up to a 50% corrosion level is considered in this study. Corrosion was experimentally induced and was simulated in other cases. Twenty-six reinforced concrete (RC) members with various corrosion levels or simulated corrosion levels were constructed and investigated. The beams with corrosion problems including those that had experimentally induced corrosion or simulated corrosion, with or without concrete cover, were repaired using carbon fiber reinforced polymer (CFRP) sheets and U-wraps. Two line loads were applied to all of the non-repaired and repaired beams constructed in this study until failure. It was found that it is conservative to model the actual corrosion by simulating the equivalent area of steel reinforcing for up to a 20% level of corrosion. For corrosion levels over 20%, the simulated corrosion over predicts the load capacity of the actual corrosion cases. When the concrete cover was lost and for a corrosion level larger than 10%, the repaired beam did not reach similar performance to that of a repaired beam with a concrete cover that was still intact. It appears that using two layers of CFRP sheet did not improve the load capacity further, but rather improved the ductility of the deteriorated RC member. Full article
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Open AccessArticle
Uncertainty Analysis of the Temperature–Resistance Relationship of Temperature Sensing Fabric
Fibers 2016, 4(4), 29; doi:10.3390/fib4040029 -
Abstract
This paper reports the uncertainty analysis of the temperature–resistance (TR) data of the newly developed temperature sensing fabric (TSF), which is a double-layer knitted structure fabricated on an electronic flat-bed knitting machine, made of polyester as a basal yarn, and embedded with fine
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This paper reports the uncertainty analysis of the temperature–resistance (TR) data of the newly developed temperature sensing fabric (TSF), which is a double-layer knitted structure fabricated on an electronic flat-bed knitting machine, made of polyester as a basal yarn, and embedded with fine metallic wire as sensing element. The measurement principle of the TSF is identical to temperature resistance detector (RTD); that is, change in resistance due to change in temperature. The regression uncertainty (uncertainty within repeats) and repeatability uncertainty (uncertainty among repeats) were estimated by analysing more than 300 TR experimental repeats of 50 TSF samples. The experiments were performed under dynamic heating and cooling environments on a purpose-built test rig within the temperature range of 20–50 °C. The continuous experimental data was recorded through LabVIEW-based graphical user interface. The result showed that temperature and resistance values were not only repeatable but reproducible, with only minor variations. The regression uncertainty was found to be less than ±0.3 °C; the TSF sample made of Ni and W wires showed regression uncertainty of <±0.13 °C in comparison to Cu-based TSF samples (>±0.18 °C). The cooling TR data showed considerably reduced values (±0.07 °C) of uncertainty in comparison with the heating TR data (±0.24 °C). The repeatability uncertainty was found to be less than ±0.5 °C. By increasing the number of samples and repeats, the uncertainties may be reduced further. The TSF could be used for continuous measurement of the temperature profile on the surface of the human body. Full article
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Open AccessArticle
CVD-Grown CNTs on Basalt Fiber Surfaces for Multifunctional Composite Interphases
Fibers 2016, 4(4), 28; doi:10.3390/fib4040028 -
Abstract
Chemical vapor deposition (CVD) is used as a method for the synthesis of carbon nanotubes (CNT) on substrates, most commonly pre-treated by a metal-catalyst. In this work, the capability of basalt fiber surfaces was investigated in order to stimulate catalyst-free growth of carbon
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Chemical vapor deposition (CVD) is used as a method for the synthesis of carbon nanotubes (CNT) on substrates, most commonly pre-treated by a metal-catalyst. In this work, the capability of basalt fiber surfaces was investigated in order to stimulate catalyst-free growth of carbon nanotubes. We have carried out CVD experiments on unsized, sized, and NaOH-treated basalt fibers modified by growth temperature and a process gas mixture. Subsequently, we investigated the fiber surfaces by SEM, AFM, XPS and carried out single fiber tensile tests. Growth temperatures of 700 °C as well as 800 °C may induce CNT growth, but depending on the basalt fiber surface, the growth process was differently affected. The XPS results suggest surficial iron is not crucial for the CNT growth. We demonstrate that the formation of a corrosion shell is able to support CNT networks. However, our investigations do not expose distinctively the mechanisms by which unsized basalt fibers sometimes induce vertically aligned CNT carpets, isotropically arranged CNTs or no CNT growth. Considering data from the literature and our AFM results, it is assumed that the nano-roughness of surfaces could be a critical parameter for CNT growth. These findings will motivate the design of future experiments to discover the role of surface roughness as well as surface defects on the formation of hierarchical interphases. Full article
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Open AccessArticle
Infrared Imaging of Cotton Fiber Bundles Using a Focal Plane Array Detector and a Single Reflectance Accessory
Fibers 2016, 4(4), 27; doi:10.3390/fib4040027 -
Abstract
Infrared imaging is gaining attention as a technique used in the examination of cotton fibers. This type of imaging combines spectral analysis with spatial resolution to create visual images that examine sample composition and distribution. Herein, we report on the use of an
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Infrared imaging is gaining attention as a technique used in the examination of cotton fibers. This type of imaging combines spectral analysis with spatial resolution to create visual images that examine sample composition and distribution. Herein, we report on the use of an infrared instrument equipped with a reflection accessory and an array detector system for the examination of cotton fiber bundles. Cotton vibrational spectra and chemical images were acquired by grouping pixels in the detector array. This technique reduced spectral noise and was employed to visualize cell wall development in cotton fibers bundles. Fourier transform infrared spectra reveal band changes in the C–O bending region that matched previous studies. Imaging studies were quick, relied on small amounts of sample and provided a distribution of the cotton fiber cell wall composition. Thus, imaging of cotton bundles with an infrared detector array has potential for use in cotton fiber examinations. Full article
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Open AccessFeature PaperArticle
Heat Transfer in Directional Water Transport Fabrics
Fibers 2016, 4(4), 26; doi:10.3390/fib4040026 -
Abstract
Directional water transport fabrics can proactively transfer moisture from the body. They show great potential in making sportswear and summer clothing. While moisture transfer has been previously reported, heat transfer in directional water transport fabrics has been little reported in research literature. In
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Directional water transport fabrics can proactively transfer moisture from the body. They show great potential in making sportswear and summer clothing. While moisture transfer has been previously reported, heat transfer in directional water transport fabrics has been little reported in research literature. In this study, a directional water transport fabric was prepared using an electrospraying technique and its heat transfer properties under dry and wet states were evaluated, and compared with untreated control fabric and the one pre-treated with NaOH. All the fabric samples showed similar heat transfer features in the dry state, and the equilibrium temperature in the dry state was higher than for the wet state. Wetting considerably enhanced the thermal conductivity of the fabrics. Our studies indicate that directional water transport treatment assists in moving water toward one side of the fabric, but has little effect on thermal transfer performance. This study may be useful for development of “smart” textiles for various applications. Full article
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Open AccessFeature PaperEditorial
Nanofibers: Friend or Foe?
Fibers 2016, 4(3), 25; doi:10.3390/fib4030025 -
Abstract Since the early 1990s nanofibers, particularly those of a carbonaceous content [1] have received heightened interest due to their advantageous physico-chemical characteristics (e.g., high strength, stiffness, semi-conductor, increased thermal conductivity and one of the highest Young’s modulus [2]).[...] Full article
Open AccessArticle
Development of Touch Probing System Using a Fiber Stylus
Fibers 2016, 4(3), 24; doi:10.3390/fib4030024 -
Abstract
This paper presents a system that can be used for micro-hole measurement; the system comprises an optical fiber stylus that is 5 µm in diameter. The stylus deflects when it comes into contact with the measured surface; this deflection is measured optically. In
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This paper presents a system that can be used for micro-hole measurement; the system comprises an optical fiber stylus that is 5 µm in diameter. The stylus deflects when it comes into contact with the measured surface; this deflection is measured optically. In this study, the design parameters of the optical system are determined using a ray-tracing method, and a prototype of the probing system is fabricated to verify ray-tracing simulation results; furthermore, the performance of the system is evaluated experimentally. The results show that the design parameters of this system can be determined using ray-tracing; the resolution of the measurement system using this shaft was approximately 3 nm, and the practicality of this system was confirmed by measuring the shape of a micro-hole 100 µm in diameter and 475 µm in depth. Full article
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Open AccessTechnical Note
Extraction of High Quality RNA from Cannabis sativa Bast Fibres: A Vademecum for Molecular Biologists
Fibers 2016, 4(3), 23; doi:10.3390/fib4030023 -
Abstract
In plants there is no universal protocol for RNA extraction, since optimizations are required depending on the species, tissues and developmental stages. Some plants/tissues are rich in secondary metabolites or synthesize thick cell walls, which hinder an efficient RNA extraction. One such example
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In plants there is no universal protocol for RNA extraction, since optimizations are required depending on the species, tissues and developmental stages. Some plants/tissues are rich in secondary metabolites or synthesize thick cell walls, which hinder an efficient RNA extraction. One such example is bast fibres, long extraxylary cells characterized by a thick cellulosic cell wall. Given the economic importance of bast fibres, which are used in the textile sector, as well as in biocomposites as green substitutes of glass fibres, it is desirable to better understand their development from a molecular point of view. This knowledge favours the development of biotechnological strategies aimed at improving specific properties of bast fibres. To be able to perform high-throughput analyses, such as, for instance, transcriptomics of bast fibres, RNA extraction is a crucial and limiting step. We here detail a protocol enabling the rapid extraction of high quality RNA from the bast fibres of textile hemp, Cannabis sativa L., a multi-purpose fibre crop standing in the spotlight of research. Full article
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Open AccessArticle
Experimental Investigation of the Effect of Short Flax Fibers on the Permeability Behavior of a New Unidirectional Flax/Paper Composite
Fibers 2016, 4(3), 22; doi:10.3390/fib4030022 -
Abstract
A new type of reinforcement for unidirectional natural fiber composites has been developed, where a paper layer is assembled with a layer of unidirectional flax yarns. The paper layer chemically and mechanically bonds to the loose yarns to maintain their alignment and enables
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A new type of reinforcement for unidirectional natural fiber composites has been developed, where a paper layer is assembled with a layer of unidirectional flax yarns. The paper layer chemically and mechanically bonds to the loose yarns to maintain their alignment and enables better manipulability of the reinforcement during stacking in the mold. Unfortunately, the paper layer adversely affects the permeability of the whole reinforcement to liquid resin and thus limits the impregnation quality of the final part. In this paper, a technique is adopted to increase the impregnation performance by modifying the architecture of the fibrous network in the paper layer. In particular, a method has been developed to replace a proportion of the Kraft fibers by short flax fibers in the paper layer, in an attempt to open the structure and increase the paper permeability. Permeability measurements show a major improvement in global reinforcement permeability. Basic mechanical properties of resulting composites were also analysed. Results show a slight decrease in modulus and strength when the paper layer is present. This is compensated by an important reduction in variability. Furthermore, increasing the flax proportion in the paper layer limits the loss of mechanical properties, while reducing variability even further. Full article
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Open AccessOpinion
Elucidating the Potential Biological Impact of Cellulose Nanocrystals
Fibers 2016, 4(3), 21; doi:10.3390/fib4030021 -
Abstract
Cellulose nanocrystals exhibit an interesting combination of mechanical properties and physical characteristics, which make them potentially useful for a wide range of consumer applications. However, as the usage of these bio-based nanofibers increases, a greater understanding of human exposure addressing their potential health
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Cellulose nanocrystals exhibit an interesting combination of mechanical properties and physical characteristics, which make them potentially useful for a wide range of consumer applications. However, as the usage of these bio-based nanofibers increases, a greater understanding of human exposure addressing their potential health issues should be gained. The aim of this perspective is to highlight how knowledge obtained from studying the biological impact of other nanomaterials can provide a basis for future research strategies to deduce the possible human health risks posed by cellulose nanocrystals. Full article
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Open AccessArticle
Effect of Polymer Concentration, Rotational Speed, and Solvent Mixture on Fiber Formation Using Forcespinning®
Fibers 2016, 4(2), 20; doi:10.3390/fib4020020 -
Abstract
Polycaprolactone (PCL) fibers were produced using Forcespinning® (FS). The effects of PCL concentration, solvent mixture, and the spinneret rotational speed on fiber formation were evaluated. The concentration of the polymer in the solvents was a critical determinant of the solution viscosity. Lower
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Polycaprolactone (PCL) fibers were produced using Forcespinning® (FS). The effects of PCL concentration, solvent mixture, and the spinneret rotational speed on fiber formation were evaluated. The concentration of the polymer in the solvents was a critical determinant of the solution viscosity. Lower PCL concentrations resulted in low solution viscosities with a correspondingly low fiber production rate with many beads. Bead-free fibers with high production rate and uniform fiber diameter distribution were obtained from the optimum PCL concentration (i.e., 12.5 wt%) with tetrahydrofuran (THF) as the solvent. The addition of N, N-dimethylformamide (DMF) to the THF solvent promoted the gradual formation of beads, split fibers, and generally affected the distribution of fiber diameters. The crystallinity of PCL fibers was also affected by the processing conditions, spinning speed, and solvent mixture. Full article
Open AccessReview
Glass Fibre Strength—A Review with Relation to Composite Recycling
Fibers 2016, 4(2), 18; doi:10.3390/fib4020018 -
Abstract
The recovery and reuse of glass fibres from manufacturing waste and end-of-life composites in an environmentally-friendly, cost-effective manner is one of the most important challenges facing the thermosetting polymer composites industry. A number of processes for recycling fibres from such materials are available
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The recovery and reuse of glass fibres from manufacturing waste and end-of-life composites in an environmentally-friendly, cost-effective manner is one of the most important challenges facing the thermosetting polymer composites industry. A number of processes for recycling fibres from such materials are available or under development. However, nearly all options deliver recycled glass fibres that are not cost-performance competitive due to the huge drop in strength of recycled glass fibre compared to its original state. A breakthrough in the regeneration of recycled glass fibre performance has the potential to totally transform the economics of recycling such composites. This paper reviews the available knowledge of the thermally-induced strength loss in glass fibres, discusses some of the phenomena that are potentially related and presents the status of research into processes to regenerate the strength and value of such weak recycled glass fibres. Full article
Open AccessArticle
3D FE Analysis of RC Beams Externally Strengthened with SRG/SRP Systems
Fibers 2016, 4(2), 19; doi:10.3390/fib4020019 -
Abstract
The purpose of this study is to evaluate, through a nonlinear Finite Element (FE) analysis, the structural behavior of Reinforced Concrete (RC) beams externally strengthened by using Steel Reinforced Grout (SRG) and Steel Reinforced Polymer (SRP) systems. The parameters taken into account were
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The purpose of this study is to evaluate, through a nonlinear Finite Element (FE) analysis, the structural behavior of Reinforced Concrete (RC) beams externally strengthened by using Steel Reinforced Grout (SRG) and Steel Reinforced Polymer (SRP) systems. The parameters taken into account were the external strengthening configuration, with or without U-wrap end anchorages, as well as the strengthening materials. The numerical simulations were carried out by using a three-dimensional (3D) FE model. The linear and nonlinear behavior of all materials was modeled by appropriate constitutive laws and the connection between concrete substrate and external reinforcing layer was simulated by means of cohesive surfaces with appropriate bond-slip laws. In order to overcome convergence difficulties, to simulate the quasi-static response of the strengthened RC beams, a dynamic approach was adopted. The numerical results in terms of load-displacement curves, failure modes, and load and strain values at critical stages were validated against some experimental data. As a result, the proposed 3D FE model can be used to predict the structural behavior up to ultimate stage of similar strengthened beams without carrying out experimental tests. Full article
Open AccessArticle
Influence of Hygrothermal Aging on Poisson’s Ratio of Thin Injection-Molded Short Glass Fiber-Reinforced PA6
Fibers 2016, 4(2), 17; doi:10.3390/fib4020017 -
Abstract
The hygrothermal aging of short glass fiber-reinforced polyamide 6 materials (PA6 GF) represents a major problem, especially in thin-walled components, such as in the automotive sector. In this study, therefore, the thickness and the glass fiber content of PA6 GF materials were varied
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The hygrothermal aging of short glass fiber-reinforced polyamide 6 materials (PA6 GF) represents a major problem, especially in thin-walled components, such as in the automotive sector. In this study, therefore, the thickness and the glass fiber content of PA6 GF materials were varied and the materials were exposed to hygrothermal aging. The temperature and relative humidity were selected in the range from −40 °C up to 85 °C, and from 10% up to 85% relative humidity (RH). In the dry-as-molded state, the determined Poisson’s ratio of the PA6 GF materials was correlated with the fiber orientation based on computer tomography (MicroCT) data and shows a linear dependence with respect to the fiber orientation along and transverse to the flow direction of the injection molding process. With hygrothermal aging, the value of Poisson’s ratio increases in the flow direction in the same way as it decreases perpendicular to the flow direction due to water absorption. Full article
Open AccessArticle
Global Consumption of Flame Retardants and Related Environmental Concerns: A Study on Possible Mechanical Recycling of Flame Retardant Textiles
Fibers 2016, 4(2), 16; doi:10.3390/fib4020016 -
Abstract
Flame retardants (FRs) have been around us for decades to increase the chances of survival against fire or flame by limiting its propagation. The FR textiles, irrespective of their atmospheric presence are used in baby clothing, pushchairs, car seats, etc. The overall FR
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Flame retardants (FRs) have been around us for decades to increase the chances of survival against fire or flame by limiting its propagation. The FR textiles, irrespective of their atmospheric presence are used in baby clothing, pushchairs, car seats, etc. The overall FR market in Asia, Europe, and the United States in 2007 was around 1.8 million metric tonnes. It is estimated that the worldwide consumption of FRs will reach 2.8 million tonnes in 2018. Unfortunately, a sustainable approach for textile waste, especially in the case of FR textiles, is absent. Incineration and landfill of FR textiles are hindered by various toxic outcomes. To address the need for sustainable methods of discarding FR textiles, the mechanical recycling of cotton curtains was evaluated. Full article
Open AccessArticle
Strengthening of Masonry Columns with BFRCM or with Steel Wires: An Experimental Study
Fibers 2016, 4(2), 15; doi:10.3390/fib4020015 -
Abstract
Nowadays, innovative materials are more frequently adopted for strengthening historical constructions and masonry structures. The target of these techniques is to improve the structural efficiency with retrofitting methods while having a reduced aesthetical impact. In particular, the use of basalt fiber together with
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Nowadays, innovative materials are more frequently adopted for strengthening historical constructions and masonry structures. The target of these techniques is to improve the structural efficiency with retrofitting methods while having a reduced aesthetical impact. In particular, the use of basalt fiber together with a cementitious matrix emerges as a new technique. This kind of fiber is obtained by basalt rock without other components, and consequently it could be considered a natural material, compatible with masonry. Another innovative technique for strengthening masonry columns consists of applying steel wires in the correspondence of mortar joints. Both techniques have been recently proposed and some aspects of their structural performances are still open. This paper presents the results of an experimental study on the compressive behavior of clay brick masonry columns reinforced either with Basalt Fiber–Reinforced Cementitious Matrix (BFRCM) or with steel wire collaring. Uniaxial compressive tests were performed on eight retrofitted columns and four control specimens until failure. Two masonry grades were considered by varying the mix used for the mortar. Results are presented and discussed in terms of axial stress-strain curves, failure modes and crack patterns of tested specimens. Comparisons with unreinforced columns show the capability of these techniques in increasing ductility with limited strength enhancements. Full article
Open AccessArticle
Electro-Optic Swept Source Based on AOTF for Wavenumber-Linear Interferometric Sensing and Imaging
Fibers 2016, 4(2), 14; doi:10.3390/fib4020014 -
Abstract
We demonstrate a novel electro-optic swept source for wavenumber-linear interferometric sensing and imaging applications. The electro-optic swept source based on an acousto-optic tunable filter (AOTF) provides high environmental stability and arbitrary drive function sweeping because the electro-optic wavelength selection does not depend on
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We demonstrate a novel electro-optic swept source for wavenumber-linear interferometric sensing and imaging applications. The electro-optic swept source based on an acousto-optic tunable filter (AOTF) provides high environmental stability and arbitrary drive function sweeping because the electro-optic wavelength selection does not depend on a mechanical moving component to tune the output lasing wavelength. We show improved stability of the suggested electro-optic swept source, compared to a conventional swept source based on a fiber Fabry–Perot tunable filter (FFP-TF). Various types of wavelength sweeping are demonstrated by applying the programmed drive function to the applied radio frequency (RF) of the AOTF. We demonstrated improved image quality of optical coherence tomography (OCT) by using the wavenumber-linear drive function of a simple triangular signal, which has a high wavenumber-linearity with an R-square value of 0.99991. Full article
Open AccessArticle
Performance of Hybrid Reinforced Concrete Beam Column Joint: A Critical Review
Fibers 2016, 4(2), 13; doi:10.3390/fib4020013 -
Abstract
Large residual strain in reinforced concrete structures after a seismic event is a major concern for structural safety and serviceability. Alternative reinforcement materials like fiber-reinforced polymer (FRP) have been widely used to mitigate corrosion problems associated with steel. Low modulus of elasticity and
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Large residual strain in reinforced concrete structures after a seismic event is a major concern for structural safety and serviceability. Alternative reinforcement materials like fiber-reinforced polymer (FRP) have been widely used to mitigate corrosion problems associated with steel. Low modulus of elasticity and brittle behavior compared to steel has made the use of FRP unsuitable in seismic resistant strictures. A combination of steel-FRP reinforcement configuration can address the problem of corrosion. Therefore, introducing a material that shows strong post elastic behavior without any decay due to corrosion is in demand. Shape memory alloy (SMA), a novel material, is highly corrosion resistive and shows super elastic property. Coupling SMA with FRP or steel in the plastic hinge region allows the structure to undergo large deformations, but regains its original shape upon unloading. In this study, the performance characteristics of four previously tested beam-column joints reinforced with different configurations (steel, SMA/steel, glass fiber reinforced polymer (GFRP) and SMA/FRP) are compared to assess their capacity to endure extreme loading. Experimental results are scrutinized to compare the behavior of these specimens in terms of load-story drift and energy dissipation capacity. SMA/FRP and SMA/Steel couples have been found to be an acceptable approach to reduce residual deformation in beam-column joints with adequate energy dissipation capacity. However, SMA/FRP is superior to SMA/Steel concerning to the corrosion issue in steel. Full article
Open AccessCommunication
Spider Silk/Polyaniline Composite Wire
Fibers 2016, 4(2), 12; doi:10.3390/fib4020012 -
Abstract
Polymerization of aniline in the presence of spider silk produces a natural fiber-based conducting polymer wire. We observed the fiber structure with polarizing optical microscopy and scanning electron microscopy. This spider-silk/PANI, a biosynthetic composite, could be the basis for organic high-performance conducting wire.
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Polymerization of aniline in the presence of spider silk produces a natural fiber-based conducting polymer wire. We observed the fiber structure with polarizing optical microscopy and scanning electron microscopy. This spider-silk/PANI, a biosynthetic composite, could be the basis for organic high-performance conducting wire. Full article
Open AccessArticle
The Durability and Performance of Short Fibers for a Newly Developed Alkali-Activated Binder
Fibers 2016, 4(1), 11; doi:10.3390/fib4010011 -
Abstract
This study reports the development of a fiber-reinforced alkali-activated binder (FRAAB) with an emphasis on the performance and the durability of the fibers in the alkaline alkali-activated binder (AAB)-matrix. For the development of the matrix, the reactive components granulated slag and coal fly
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This study reports the development of a fiber-reinforced alkali-activated binder (FRAAB) with an emphasis on the performance and the durability of the fibers in the alkaline alkali-activated binder (AAB)-matrix. For the development of the matrix, the reactive components granulated slag and coal fly ash were used, which were alkali-activated with a mixture of sodium hydroxide (2–10 mol/L) and an aqueous sodium silicate solution (SiO2/Na2O molar ratio: 2.1) at ambient temperature. For the reinforcement of the matrix integral fibers of alkali-resistant glass (AR-glass), E-glass, basalt, and carbon with a fiber volume content of 0.5% were used. By the integration of these short fibers, the three-point bending tensile strength of the AAB increased strikingly from 4.6 MPa (no fibers) up to 5.7 MPa (carbon) after one day. As a result of the investigations of the alkali resistance, the AR-glass and the carbon fibers showed the highest durability of all fibers in the FRAAB-matrix. In contrast to that, the weight loss of E-glass and basalt fibers was significant under the alkaline condition. According to these results, only the AR-glass and the carbon fibers reveal sufficient durability in the alkaline AAB-matrix. Full article