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The desire for lightweight, carbon-negative materials has been increasing in recent years, particularly as the transportation sector reduces its global carbon footprint. Natural fibers, such as flax fiber and their composites, offer a compelling combination of properties including low density, high specific strength, and carbon negativity. However, because of the low modulus and high variability in performance, natural fibers can't compete with glass fibers as structural reinforcements in polymer composites. In this study, flax technical fibers were treated in supercritical CO2 (scCO2), and the effects of this treatment on the morphology and properties of flax fibers are reported. Treatment in scCO2 successfully resulted in higher fiber modulus and strength by 33% and 40%, respectively. Fiber porosity was reduced by 50% and morphological changes to the fibers were observed. Specifically, fiber lumen collapsed during treatment and micro/mesoporosity was reduced by 27%. Treated flax fibers were used to create 30 vol% unidirectional flax-epoxy composites. ScCO2 treatment raised composite modulus and strength by 33% and 25%, respectively. Because of the dependence between technical fiber size and mechanical properties, the relationship between fiber modulus and fiber size were created and applied to the rule-of-mixtures. This relationship were found to be viable representations of the fiber performance within each composite. Overall, the treatment developed in this study has the potential to significantly improve natural fiber properties, enabling their consideration for use in lightweight, semi-structural composites. [ABSTRACT FROM AUTHOR]

Novel ultra-high-performance concretes (UHPCs) made with calcium-oxide-activated materials (CAM), modified synthetic macro (MSM) fibres, glass fibres and steel fibres were developed. The mechanical and durability properties of UHPC-CAM specimens made with the different fibre types were tested and compared. The microstructure of the samples was examined using scanning electron microscopy (SEM). The environmental impacts of the mix designs were assessed using the Impact 2002+ method, a life cycle assessment tool. The results showed that the UHPC-CAM made with glass or MSM fibres had a high compressive strength (>110 MPa) and improved ductility. These specimens also had low water absorption and high electrical resistance, indicating low corrosion risk. SEM analyses showed that the MSM fibres created a denser geopolymer matrix than the glass fibres. The UHPC-CAM was found to have a lower environmental impact than conventional UHPC in terms of human health, ecosystem quality, carbon dioxide footprint and use of resources. MSM fibres were determined to be the most eco-friendly fibres for UHPC-CAM production. [ABSTRACT FROM AUTHOR]

Globally, the operational energy usage in buildings accounts for about 30% of the final energy consumption and 26% of the energy‐related emissions. In 2022, the building sector recorded 132 EJ in energy usage and 9.8 Gt of CO2 emissions. Energy‐intensive space heating and air conditioning play a significant role in these statistics, with slightly over half of US home energy usage attributed to them. Thus, energy‐efficient buildings, incorporating effective thermal insulation, are essential for addressing climate change. Fiberglass is the dominant insulation material used in US homes, comprising about 71% of installations. The paper discusses the fundamental aspects of heat transfer in fibrous insulation in general and fiberglass insulation in particular. The thermal performance of a fibrous insulation is characterized by an effective thermal conductivity, which combines conductive and radiative terms. The former represents heat conduction through the gas–fiber network and the latter the absorption and the scattering of thermal radiation by the fibers. The paper describes mathematical formulations for these terms and presents results showing the dependence of the effective conductivity on insulation density, fiber diameter, and temperature. The predicted values of the effective conductivity are found to be in good agreement with the measured ones. [ABSTRACT FROM AUTHOR]

Utilizing waste resources in concrete manufacturing, while employing alternative components and minimizing the Ordinary Portland Cement (OPC) production, is a matter of great importance owing to several environmental and stability considerations. OPC is the fundamental component implemented in the conventional concrete production process. However, the OPC industry has raised environmental concerns since it produces mass amounts of carbon dioxide (CO2). A more sustainable substance, utilizing metakaolin as pozzolanic material and local ash as a filler can serve as an OPC substitute, thereby reducing the CO2 release into the environment. This work examines the impact of incorporating sustainable recycled copper fibers as well as alkali resistance glass fibers on the properties of perlite structural lightweight aggregate concrete containing local, sustainable materials. The research includes slump, density, and thermal conductivity tests along with tests conducted during the 7, 28, and 60 days of curing for compressive, flexural, and split tensile strength. The concrete was reinforced with 1% hybrid fibers by volume. The results reveal that adding fibers to lightweight concrete reduces the slump and increases density and thermal conductivity, while it also increases the compressive, flexural, and split tensile strengths. [ABSTRACT FROM AUTHOR]

In our investigation, we subjected eleven reinforced concrete beams to a four-point bending system to explore the impact of varying fibre and ferrocement contents on their structural behaviour. These beams, measuring 1.7 m in length, featured a rectangular cross-section with dimensions of 150 mm by 300 mm. Our study focused on three key variables: steel fibre content (at levels of 0.5%, 1%, and 1.5%), glass fibre content (also at 0.5%, 1%, and 1.5%), and ferrocement content (evaluated with one or two layers of welded or expanded wire mesh). Our findings revealed that incorporating fibres with minimal shear reinforcement significantly enhanced the beams' performance. Specifically: The specimen reinforced with 1.5% steel fibres exhibited the highest ultimate failure load, surpassing the control beam by an impressive 41.87%. The 0.5% glass fibre specimen experienced the least deflection at the ultimate load compared to the control beam. The 1.5% glass fibre specimen demonstrated superior energy absorption compared to the control specimen. Notably, using two layers of welded wire mesh proved most effective in enhancing the ultimate failure load when compared to both the control specimen and other ferrocement-strengthened beams. [ABSTRACT FROM AUTHOR]

A model is presented for calculating the electric field profiles of transverse modes in fibres. Using this model, the electric field propagation of transverse modes was calculated and compared in both bent and straight Yb and Ho fibres. Our simulations revealed that the field intensities of the modes did not consistently increase or decrease by bending as expected, but rather fluctuated as the bending radii of the fibres changed from 1 to 100 cm. Additionally, it was observed that at certain bending radii, the modes of the fibres became deformed and transitioned into higher modes. Furthermore, the extent to which the modes stretched towards cladding due to bending was calculated. To provide a more comprehensive analysis of the results and investigate the effects of the physical parameters of the fibres on the bent fibre modes, simulation results were presented for two different V numbers and core radii. [ABSTRACT FROM AUTHOR]

The main objective of the research is developed toward adsorption electronic devices (Interface material) with the performance examined by the physical, mechanical, and thermal properties of the E‐glass fiber reinforced with the epoxy composite and particulate dispersed into the matrix in partial fulfillment of tiny amount of aluminum powder particles and MWCNT. Composite membranes with 15 wt.% E‐glass fiber and 2 wt.%, 4 wt.%, and 6 wt.% fine aluminum powder particle concentrations were partially filled with 0 wt.%, 0.5 wt.%, and 1.0 wt.% MWCNTs. Vacuum lay‐up technique is used to create the better adhesive hybrid composite, which is then assessed of the characteristics of the materials. The maximum thermal conductivity of EAEM2 (E‐Epoxy, A‐Aluminum particle, E‐E‐glass fiber, M‐MWCNT) is 0.3057 W/mK. The tensile, bending, and impact strengths of EAEM1 composites are higher than those of EAEM2 and EAEM3 (average values of EAEM1 composites: 86 MPa, 123.33 MPa, and 90.66 J/m2). However, the Shore‐D hardness of EAEM3 is 95.33. The test findings demonstrate a significant improvement in thermal properties with minimal marginal decrements in mechanical capabilities when carbon allotropes are increased. The composite system's morphology (EAEM3) demonstrates a clustered distribution of aluminum powder particles in the matrix. [ABSTRACT FROM AUTHOR]

The object of research is modified epoxy composite materials containing fibrous fillers treated in physical fields. The technological features of the development of tribotechnical epoxy composites, which must withstand the effects of elevated temperatures, have been considered. In this case, it is necessary to modify the structure of the epoxy polymer matrix, which is achieved as a result of the introduction of heat-resistant organosilicon varnish. Organosilicon varnishes and chopped fibers contain technological additives, which complicates the process of structuring epoxy composites and leads to the appearance of structural defects. Removal of technological additives and cleaning the surface of the aramid and glass fibers from lubricants is possible as a result of processing the components of the composition in physical fields. There is a need to study the influence of physical fields on the structuring processes of the epoxy system and the formation of the structure of epoxy composites with specified properties. Modified epoxy composites contain chopped aramid and glass fibers treated with ultrasound. The tribotechnical characteristics of epoxy composites were studied at a sliding speed of V=1.0 m/s with a change in specific load from 0.5 MPa to 1.5 MPa. The temperature in the tribocontact zone during frictional interaction rises to 100 °C with an increase in the specific load. An increase in the density of the surface layer of tribocontact of epoxy composites with fillers treated in physical fields was revealed. The practical recommendations have been compiled for the implementation of the treatment technology of components in physical fields, which ensures structuring of epoxy composites with high tribotechnical characteristics. [ABSTRACT FROM AUTHOR]

Glass fibre-reinforced polymer (GFRP) wastes may be mechanically processed into small strips called "macro fibres," which were used as short reinforcement fibres to produce macro fibre reinforced concrete (MFRC). The addition of such macro fibres into concrete has proven to be effective in enhancing the flexural strength and toughness of concrete, but it also slightly reduces the compressive strength of concrete. This paper presents a study on the behaviour of CFRP-confined MFRC. A total of 84 CFRP-confined MFRC cylinders were prepared and tested in axial compression. The test parameters included the CFRP confinement stiffness, macro fibre content, and fibre length. The test results show that the compressive strength and ultimate axial strain can be significantly enhanced through the use of CFRP confinement. The ultimate axial strain of CFRP-confined concrete with macro fibres is slightly higher than that without macro fibres. The test results were compared with two well-known stress-strain models for FRP-confined concrete, including Teng et al.'s design-oriented model and Jiang and Teng's analysis-oriented model. A comparative analysis showed that both models slightly underestimate the compressive strength and slightly overestimate the ultimate axial strain for CFRP-confined MFRC. [ABSTRACT FROM AUTHOR]

It is vital to maximize the safety of outdoor constructions, airplanes, and space vehicles by protecting against the impact of airborne debris from increasing winds due to climate change, or from bird strikes or micrometeoroids. In a widely-used compression-molded short glass fiber polyester bulk-molded compound (SGFRP-BMC) with 55% wt. CaCO3 filler, the center of the mother panel has lower impact strength than the outer sections with solidification texture angles and short glass fiber (SGF) orientations being random from 0 to 90 degrees. Therefore, a new double-step process of: (1) reducing commercial fiber length without change in molding equipment; followed by a (2) 0.86 MGy dose of homogeneous low-voltage electron beam irradiation (HLEBI) to both sides of the finished samples requiring no chemicals or additives, which is shown to increase the Charpy impact value (auc) about 50% from 6.26 to 9.59 kJm−2 at median-accumulative probability of fracture, Pf = 0.500. Shortening the SGFs results in higher fiber spacing density, Sf, as the thermal compressive stress site proliferation by action of the CTE difference between the matrix and SGF while the composite cools and shrinks. To boost impact strength further, HLEBI provides additional nano-compressive stresses by generating dangling bonds (DBs) creating repulsive forces while increasing SGF/matrix adhesion. Increased internal cracking apparently occurs, raising the auc. [ABSTRACT FROM AUTHOR]

This work compares the tensile and fatigue behavior of unidirectional glass fiber/epoxy (GFRPs) and basalt fiber/epoxy (BFRPs) composites manufactured using vacuum-assisted resin infusion molding (VARIM). The tensile and fatigue tests are performed, and results show that both GFRPs and BFRPs have very similar tensile behavior, whereas BFRPs perform better than the GFRPs in terms of fatigue life and degradation of properties, showing about 75 MPa more fatigue limit. The S-N curve shows that BFRPs resist fatigue failure and stiffness degradation due to their better interfacial adhesion. Fractographic observations reveal fatigue failure mechanisms of both BFRPs and GFRPs. From the regression analysis performed, an S-N curve was fitted with a model available in the literature, and regression parameters were calculated. Dynamic mechanical analysis of both BFRPs and GFRPs was performed to evaluate parameters like glass transition temperature, storage modulus, and loss modulus. From the findings of this research, BFRPs may be recommended as a suitable alternative to GFRPs. Highlights • This article compares the tension-tension fatigue properties of unidirectional GFRPs and BFRPs. • From the research work, the authors found that BFRPs perform better than GFRPs under fatigue loading. • The stiffness degradation behavior of GFRPs and BFRPs are studied and compared. • Scanning electron micrographs of fractured samples are used to observe fatigue failure mechanisms. • Dynamic mechanical analysis (DMA) was performed to determine the storage modulus, loss modulus, glass transition temperature, and damping coefficient (tand) for both composites. [ABSTRACT FROM AUTHOR]

Because the physical properties of carbon fiber and glass fiber are very different, the fiber volume fraction in carbon/glass hybrid fiber composites cannot be tested by burning method or digestion method, respectively. Furthermore, these methods partially consume the fiber, especially for carbon fibers. To investigate the fiber volume fraction in carbon/glass hybrid fiber composites correctly, the test method is put forward. The burning method and the digestion method were combined to calculate the volume fraction of carbon fiber and glass fiber, respectively. The results show that the relative error between the measured value and the theoretical value is very small. The result of the present work implies that the feasibility and accuracy of this method through experimental verification. [ABSTRACT FROM AUTHOR]

The use of an open-graded friction course (OGFC) as a road surface demonstrates significant advantages in reducing driving noise and improving road drainage and safety. This study aims to enhance the overall performance of OGFC-13 by incorporating double-adding fiber technology. Laboratory tests were conducted on six OGFC-13 mixes modified with varying fiber ratios of lignin fibers (LFs) and glass fibers (GFs). Both GF and LF significantly improved high-temperature performance, with dynamic stability values increasing proportionally to GF content. The LF:GF = 0.15:0.15 ratio achieved peak shearing strength, demonstrating better improvement over single-fiber modification. Furthermore, both fibers effectively enhanced resistance to cracking, with GF-reinforced specimens excelling in bending stress and LF-reinforced specimens demonstrating the highest flexural strain. Water stability evaluations highlighted the substantial positive impact of LF and GF, with simultaneous addition resulting in superior moisture stability compared to single-fiber modifications. Anti-stripping performance assessments indicated that the LF:GF = 3:0 ratio exhibited the best performance. In fatigue performance, both LF and GF enhanced fatigue life, with GF outperforming LF. The LF:GF = 0.15:0.15 ratio achieved a balanced fatigue performance. Results from the radar evaluation method underscored a more comprehensive improvement in road performance achieved through double-adding technology. The LF:GF = 0.15:0.15 ratio emerged as the optimal choice for overall road performance. [ABSTRACT FROM AUTHOR]

The purpose of the study was to evaluate selected mechanical properties and structural characteristics of samples manufactured using composite filament fabrication (CFF) technology from Onyx material, whichwas filled with continuous glass fiber. Selected mechanical properties were correlated with the density of the resulting composite to determine the specific strength of the fabricated parts. The test specimens were manufactured on a Mark Two Enterprise machine (Markforged, USA) using composite filament fabrication (CFF) technology. The material used was polyamide 6.6 with a 20% short carbon fiber content with the trade name Onyx. Continuous glass fiber was used to reinforce the fabrication. The density of the manufactured samples was determined using a hydrostatic method. Methanol was used as the liquid. By determining the density of the samples, it was possible to estimate through appropriate calculations what specific strength and specific modulus the obtained composites would have. Determination of tensile and flexural strengths was carried out in accordance with ISO 527-1:2012 and ISO 178:2003. Determination of the impact tensile strength of the samples was carried out in accordance with ISO 8256, the beams were tested using the A method. Due to the high impact tensile strength, two 1 mm notches with an angle of 45°were made on the specimens. The image of the sample structure obtained by the CFF method was recorded using a CT scanner. A thermogravimetric test (TG) of the Onyx matrix material was carried out. The samples were tested approximately 72 hours after fabrication. Filling the samples with continuous glass fiber above 50% leads to a slight increase in impact resistance. The density of the composite increased by only 16% relative to the reference samples, resulting in a 389% increase in the maximum average flexural strength. Despite significant discontinuities in the structure of the produced composite, it was possible to record an increase in tensile strength and Young's modulus by 606% and 370%, respectively. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS) polymers are widely used in insulation and packaging applications. If their waste hasn't been managed well and due to their long degradation time, they will cause severe environmental problems for human beings, plants, and animals. Therefore, recycling could be one of the acceptable solutions to overcome such problems in addition to reinforcing them to recover the decay in properties resulting from recycling. In this work two types of EPS have been recycled at different temperatures from 140 to 260°C, and then reinforced by E-glass fibers in mat form and as random short fibers with varied composition from 5 to 25 wt%. The samples have been prepared by homemade thermal press and the tensile properties such as strength, modulus, and ductility have been investigated showing an obvious enhancement of these properties upon an increase in temperature to certain level and with fiber content and length exceeding their critical lengths. Furthermore, interfacial adhesion has been studied by estimating the strength and modulus efficiency factors. The results show that the E-glass fibers could improve the strength with more than 300%. [ABSTRACT FROM AUTHOR]

To investigate the real anchorage performance of basalt and glass hybrid fiber reinforced plastic (FRP) anchors in external corrosive environments. In this paper, a combination of experimental studies and finite element analysis was used. By carrying out pull‐out tests of basalt and glass hybrid FRP anchors under the synergistic effect of freeze–thaw cycles and alkaline environment, the effects of factors such as hole diameter, anchorage length, and mortar strength on their anchorage performance and durability were investigated. Critical corrosion time was introduced to determine the degree of corrosion of the anchor rods. After that, it combined with numerical simulation to reveal the degradation mechanism of the anchorage performance of hybrid anchors. The results showed that the best anchorage performance of basalt/glass hybrid FRP anchors was achieved when the hole diameter was 24 mm, the anchorage length was 175 mm, and the mortar strength was 45.5 MPa. The ultimate pull‐out load was up to 122.16 kN. When the time did not exceed the critical corrosion time, the ultimate load‐carrying capacity of basalt and glass hybrid FRP anchors increased by 9.3% compared to the uncorroded environment. Beyond the critical corrosion time, the ultimate load‐carrying capacity was reduced by 23.3% and the anchorage performance was degraded. In addition, the contact interface between the anchor and the mortar is the weak area of the anchoring structure, which should be focused on in the later design of the actual project. Highlights: Basalt/glass hybrid FRP anchors have good corrosion resistance.The anchoring performance of hybrid FRP anchors under the coupled environment is studied.Hole diameter and anchoring length have more influence on the anchor performance.The concept of critical corrosion time is put forward.The failure mechanism and coupling environment influence are revealed by FES. [ABSTRACT FROM AUTHOR]

This study is dedicated to conducting a comprehensive examination, both experimentally and numerically, to characterize the mechanical properties of a composite material composed of Alfa fibres and unsaturated polyester resin. In pursuit of this objective, we diligently prepared composite specimens in accordance with the ASTM D3379-75 standardization. The Alfa fibres used were prepares using a purely natural-based extraction technique, which retains approximately 78% of the composite's performance achieved through chemical treatment. The resulting composite consists of polyester resin reinforced with varying weight fractions of fibres, ranging from 0 to 18%.The test results of the manufactured bio-composite show that specimens with an 18% weight fraction offer a tensile strength of 49.749 MPa, whereas specimens with a 10% weight fraction exhibit a strength of 44.312 MPa. Additionally, the specimens with 18% fibre reinforcement exhibit a net increase in Young's modulus by 46% compared to the fibre-free composite, with Young's modulus ranging from 1469.66 MPa to 2726 MPa. When compared with composites based on fibre glass, the introduced bio-composite with 18% Alfa fibres exhibits similar stiffness to that of glass fibres. Additionally, the outcomes from the Finite Element Model (FEM) reveal a remarkable agreement with the experimental data, underscoring the practical applicability of the proposed methodology and tools for accurately simulating tensile tests in composite structures. [ABSTRACT FROM AUTHOR]

In a wind turbine, blades are an essential component. In recognition of their remarkable qualities, nanoparticle-reinforced composites (also known as nanocomposites) are becoming increasingly popular among academics and companies. In preceding investigations of wind turbine blades, it was discovered that manufacturing issues, such as cracks in the supporting airfoil transition area, fiberglass, and hardener, were brought on by insufficient resin availability. For the effective investigation of wind turbine blades, a unique e-glass fiber and nanocomposite using AW 106 epoxy have been presented. The primary purpose of this research is on the viability of nanocomposites based on montmorillonite, specifically for use in wind turbine blades. The production and in-depth investigation of nano SiO2-Al2O3-TiO2 montmorillonite dispersed E-glass fiber/AW 106 epoxy composites are the subjects of the investigation of proposed method. The experimental findings were confirmed by GRA and SEM analysis in ANSYS to predict wind turbine blade failures, evaluate the blades’ hardness, and test the edge and flap loading conditions. As the result, demonstrated that nanocomposite has a tensile strength of Al2O3with 1% high with a value of 106 MPa, Al2O3with 1% withstands the highest number of failure cycles with 273, Rockwell number is 43, and the maximum value of Al2O3is 0.992 in GRA with various materials. [ABSTRACT FROM AUTHOR]

A significant change in the refractive index profiles for the large mode area phosphoroaluminosilicate (PAS) core optical fibers was observed in comparison to that in preforms. This study shows that the refractive index of the PAS core can vary from negative (in preform) to positive (in fiber), and the difference in the refractive index between the core and preform can exceed a few thousand. By measuring a large set of fibers with different concentrations of P2O5 and Al2O3, we define the refractivity of each dopant (P2O5, Al2O3 and AlPO4 joint) after drawing fiber from the preform and discuss the possible origin of the observed refractive index variation. [ABSTRACT FROM AUTHOR]

Optimizing the mechanical characteristics of cemented tailings backfill (CTB) and quickly identifying its damage state under external loading, this study compares and prepares CTB specimens without fiber, doped with polypropylene fiber (PF), doped with glass fiber (BL), and doped with polypropylene and glass blended fiber (PB). Uniaxial compression and acoustic emission (AE) monitoring experiments are also conducted. Based on the cumulative energy of AE, the damage ontology model of CTB was developed. As shown by the study's findings, adding various fibers can greatly enhance the filler body's uniaxial compressive strength (UCS). BL has the greatest effect, followed by PB, while PFs have the least effect. Furthermore, the fibers primarily prevent the growth of crack extension by extending or breaking themselves, The results of the tests on acoustic emission revealed that the fiberless filler's signals were more active prior to the peak point and less intense in the later stages of the damage, whereas the fiber-doped filler's signals began to increase following the peak point and remained high. Thus, the damage model curves of various fiber-filled bodies are constructed based on the cumulative energy of acoustic emission, and the experimental data verification shows that the two have good consistency, suggesting that the established theoretical model can serve as a basis of reference for assessing the filled bodies' damage state. [ABSTRACT FROM AUTHOR]

Nowadays, additive manufacturing techniques such as the Fused Filament Fabrication appear to be among the most promising methods for enabling modern industry to produce components of high geometrical complexity. The main characteristic of this method is the deposition of thermoplastic polymers that can be further reinforced with chopped and/or continuous fibers that attribute to the product some unique structural characteristics. Nevertheless, the process is susceptible to a variety of defects that are derived from the fabrication process parameters, such as porosity, insufficient fiber impregnation with the polymer and fiber disorientation. On the other hand, since the applicability of the process depends on the development of numerical tools for assessing the effects of these defects, the accurate detection and quantification of them is a crucial part of it. In the present work, these defects are studied experimentally by implementing an X-ray computed tomography testing campaign. The manufacturing defects are identified using well-established techniques while a complete analysis of the distribution of porosity is presented for various zones of Onyx, Onyx/Carbon and Onyx/Glass fiber reinforced structures. Finally, the tendency of the overall pore content to increase with increasing number of continuous fiber reinforcement was identified as well as porosity variations in printing direction are presented. [ABSTRACT FROM AUTHOR]

M-type optical fibers in which a core is surrounded by a thin ring layer with a higher refractive index have attracted increasing attention in recent years. One of their advantageous features is the ability to operate a non-fundamental LP02 mode possessing unusual dispersion properties, namely, a zero-dispersion wavelength (ZDW) shifted to the short wavelength region relative to the material ZDW. The LP02 mode can be selectively excited since it is predominantly localized near the core, while the fundamental LP01 and other higher modes are localized near the ring (for proper fiber parameters). In this paper, we present a comprehensive theoretical analysis of effective dispersion tailoring for the HE12 mode of highly nonlinear chalcogenide glass fibers (for which the LP mode approximation fails due to large refractive index contrasts). We demonstrate fiber designs for which ZDWs can be shifted to the spectral region < 2 μm, which is of great interest for the development of mid-IR supercontinuum sources and frequency-tunable pulse sources with standard near-IR pumping. We obtained the characteristic equation and solved it numerically to find mode fields and dispersion characteristics. We show the possibility of achieving dispersion characteristics of the HE12 mode with one, two, three, and four ZDWs in the wavelength range of 1.5–5.5 μm. We used a modified genetic algorithm (MGA) to design fibers with desired dispersion parameters. In particular, by applying an MGA, we optimized four fiber parameters and constructed a fiber for which HE12 mode dispersion is anomalous in the 1.735–5.155 μm range. [ABSTRACT FROM AUTHOR]

Here, we report on core–clad bioactive borosilicate fibers, that we have prepared both with round and rectangular cross‐section profile. The exposed approach, which relies on the stacking and drawing of glass slabs, demonstrates our ability to develop bioactive‐based glass fibers with tailored cross‐section profiles. Tens‐of‐meters‐long fibers were successfully drawn, although suffering from elevated losses in the case of the rectangular ones. The response of the fibers in simulated body fluid was studied for both geometries. We found that a round cladding can act as protective layer, tempering effects of the corrosion. We also noticed that rectangular fibers are more prone to degradation, the enhanced corrosion beginning from their sharp corners as they accumulated residual tensile stress during drawing. To the best of our knowledge, this is the first report on the effect of residual tensile stresses from surface tension deformations applied to the corrosion of rectangular fibers. As geometry plays a critical role on the biodegradation behavior of the fiberglass, we believe the enclosed results could lead to the design of fiber devices with tailored cross‐section profile in order to tune their rate of degradation on solely based geometrical effects. [ABSTRACT FROM AUTHOR]

Additive manufacturing of fibre-reinforced composites show high potential for fabrication of next-generation lightweight complex structural parts. In this study, the effects of building orientation and fibre type, i.e. carbon fibre (CF), and glass fibre (GF), on the mechanical properties of acrylonitrile butadiene styrene (ABS) composites fabricated by fused deposition modelling (FDM) were investigated. The mechanical properties, namely, tensile strength, elastic modulus, hardness, and toughness, were analyzed for flat, on-edge, and upright building orientations. Results revealed that building orientation significantly influences several mechanical properties; in-plane (flat and on-edge) orientations produced the best mechanical properties, whereas upright orientations produced the worst. However, building orientation had little effect on material hardness. Further, compared to the elastic modulus and tensile strength of pure ABS, those of CF-reinforced ABS (CF–ABS) increased by 800% and 500%, respectively, and those of GF-reinforced ABS (GF–ABS) increased by 400% and 400%, respectively, proving that reinforcing ABS with either CF or GF improves the tensile properties. The impact energy of CF–ABS (0.5 J) was lower than that of GF–ABS (1.1 J) because of the brittleness of CF. Fracture surface analysis was performed via scanning electron microscopy (SEM) which gave insight to the nature and mode of fracture of the failed specimens. The most common defects on the printed specimens were void formation, fibre pullout, and poor bonding between fibre and matrix. [ABSTRACT FROM AUTHOR]

Abundant research on geopolymer concrete in the last two decades has provided worldwide acceptability in conventional structural applications. The high-impact applications of geopolymers are mostly limited because they are quasi-brittle in nature and show moderate crack resistance; hence, they require suitable reinforcing materials such as fibers. This paper reports a study to assess the strength and durability properties of fly ash-based geopolymer concrete (FA-GPC) prepared with novel C-glass fibers. The binder mix was comprised of Fly Ash (FA), Lime (L), Silica Fume (SF) and was activated by sodium hydroxide (12 M) and sodium silicate solution, followed by curing under ambient conditions. Glass fibers were utilized in varying proportions (0.125, 0.25, 0.375, 0.5, 0.625, and 0.75%), by weight of the binder mix. It was found that the incorporation of 0.5% glass fiber significantly increased the compressive strength, split tensile strength, and flexural strength properties. From the durability perspective, the samples exhibited good resistance against seawater, MgSO4 solution, and H2SO4 when compared with the control mix. Further, the Scanning Electron Microscope (SEM) analysis was employed to explore the nature of the geopolymer–fiber matrix. It was revealed that excellent interfacial bonding existed between fiber and the geopolymer matrix. The results indicate that addition of C-glass fibers significantly improves the overall mechanical performance of FA-GPC. The research presented here establishes the advantages of using C-glass fibers-based geopolymer concrete, thus encouraging its broader utilization. [ABSTRACT FROM AUTHOR]

The main aim of this work is to comparatively reveal the effect of fibre type, length and content on compressive strength and microstructure of structural geopolymer concrete (GPC) produced under constant mixture and curing parameters in order to address the significant gap in present literature. Firstly, GPCs with different NaOH concentrations (i.e., 6, 9, 12 and 15 M) and activator solution/binder (a/b) ratios (i.e., 0.45 and 0.55) were produced in ambient curing condition, and optimum production parameters were determined based on the preliminary evaluations. Then, glass and polypropylene fibres in 6‐mm length (GS6 and PP6) and polyamide and polypropylene fibres in 12‐mm length (PY12 and PP12) were included in GPCs at ratio of 0.4%, 0.8% and 1.2% (by volume). Compressive strength, apparent porosity, bulk density, ultrasonic pulse velocity (UPV), X‐ray diffraction (XRD) and scanning electron microscope (SEM) analysis of GPC samples were carried out comparatively. The inclusion of GS6 fibre enhanced the compressive strength thanks to fibre surface being covered by geopolymer gel and the strong adhesion between GS fibre and geopolymer matrix. SEM images of fibre reinforced GPC (FRGPC) also confirmed the experimental findings, which were attributed to improvement in compressive strength. Regardless of the fibre type, the maximum compressive value strength was obtained from GPC specimens with 0.4% fibre and then decreased. Higher fibre inclusions led to poor compaction, workability issues and inhomogeneous fibre dispersions. A very good relation (R2 = 0.98) was acquired between UPV and compressive strength values of GPC/FRGPC samples. [ABSTRACT FROM AUTHOR]

Modern methods of modification of chemical fibers (CF) and fibrous materials on their basis, first of all, chemical methods of treatment, in absolute majority at improvement of some properties of a material, essentially worsen other properties, or the effect of improvement is not significant and (or) disappears with time. The low-energy ion flow (LEIF) treatment method generated from a high-frequency capacitive (HFC) or capacitively coupled plasma (CCP) discharge at reduced pressure improves certain fiber properties, without deteriorating other properties, while maintaining the long-term effect and without ecological harm in the treatment process. The paper shows the effects of LEIF on the strength and adhesion characteristics of carbon, aramid and glass fibers, fibers based on ultra-high molecular weight polyethylene (UHMWPE) and composites based on them. [ABSTRACT FROM AUTHOR]

Aimed to expand applications of aramid fiber fabrics and provide a reference for select fibers for filter bags using in high temperature flue gas filtration, properties such as filtration performance, temperature resistance, wear resistance, folding endurance, corrosion resistance and flame retardance of aramid fibre needle punched nonwoven fabrics were measured, in comparison with polyimide fiber needle punched nonwoven fabrics and glass fiber woven fabrics. It is found that aramid fiber fabric exhibits excellent temperature resistance. The tensile strength remains unchanged after thermal treatment under 220 °C for 24 hours. The folding endurance and corrosion resistance are excellent. The filtration performance of fabrics composited with 1 D aramid fibers is excellent while its flame retardance and wear resistance should be improved by PTFE emulsion impregnation. [ABSTRACT FROM AUTHOR]

Epoxy‐based glass fiber nanocomposites (EGFCs) have good static mechanical properties but lack in impact strength. Addition of thermoplastic fillers to EGFCs enhanced the impact strength but with lowered static properties. To overcome this issue, compatibilized polyethylene (PE) fibers and silanized clay platelets were reinforced in the EGFCs. The unique properties of PE fibers such as good toughness, high strength, resistance to chemicals, and light‐weight made them an ideal choice for this purpose. EGFCs were processed through vacuum‐assisted resin infusion molding (VARIM) technique and resulted in significant improvements in an impact strength. Compatibilization of nanoclay/PE fibers was confirmed using FTIR and SEM‐EDS analysis. Nanoclay morphology in EGFCs was determined using XRD and TEM analysis. Reinforcement of maleic anhydride grafted PE fibers and silanized nanoclay in EGFCs significantly increased the impact strength by160% over the reference EGFC (without nanoclay/PE fibers). FE‐SEM micrographs showed improved interfacial interaction among various constituents of EGFCs resulting in superior mechanical performance. The newly developed EGFCs have myriad applications in various industries, namely, automotive (bumpers, frames for racing bicycles etc.), marine (hulls, decks, etc.), aviation (radome, stabilizers, etc.), and sports (archery bows, vault poles, etc.). Highlights: Multi‐scale filler‐reinforced EGFCs fabricated through VARIM process.Compatibilized reinforcement significantly improved impact strength.Silanization of nanoclay validated with FTIR & morphology with XRD/TEM technique.SEM‐EDS and FTIR confirmed successful compatibilization of PE fibers.SEM showed improved interfacial interaction among various constituents of EGFCs. [ABSTRACT FROM AUTHOR]

This study aims to investigate the mechanical properties of hybrid polypropylene and ethylene-propylene-monomer (EPDM)-based nanocomposites reinforced with graphene nanosheets, nanoclay, and glass fibers. The response surface methodology was the study design. An internal mixer and a hot press machine were used to prepare the samples, including 0, 1, and 2 wt% of graphene nanosheets, 0, 3, and 6 wt% of nanoclay, 0, 10, and 20 wt% of glass fiber, and 0, 5, and 10 wt% of EPDM. To determine the tensile strength, tensile tests were conducted, and tensile modulus and impact tests were run to assess the impact strength of the compounds. Scanning electron microscopy images were taken to investigate the dispersion of nanoparticles and glass fibers in the polymer. The results showed the formation of agglomeration at high percentages of graphene nanosheets and nanoclay. The addition of lower weights of graphene nanosheets improved the impact strength, tensile strength, and tensile modulus by 23, 46 and 16%, respectively. Also, the use of low weight percentages of nanoclay increased the tensile strength by 21%, and its use at high weight percentages weakened the mechanical properties. The use of glass fibers increased the impact strength and tensile modulus by 18 and 24%, respectively. Its use first increased and then decreased the tensile strength. While the incorporation of EPDM increased the impact strength by 57%, it negatively affected the tensile behavior. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the bearing capacity-settlement behavior of strip footing settling on sand soil randomly reinforced with glass fiber, basalt fiber, macromesh fiber, and four different hybrid fiber additives in which these fibers are used together. Model tests were carried out in the laboratory on the strip footing and placed on the unreinforced and reinforced sand with different fibers. In the study, model tests were carried out on seven types of randomly reinforced soils by using glass, basalt, macrame, and mixtures of these fibers as reinforcement. In the model tests, two different fiber contents, 1% and 2%, and two different fiber lengths, 24 mm and 48 mm, were used. Tests were carried out with Dr = 30% and 50% relative density, and reinforcement depths 1B, 2B, and 3B were selected. In addition, the photographs taken during the test were analyzed with the particle image velocimetry (PIV) method and the displacements on the soil were examined. As a result of the reinforced and unreinforced model tests, the highest ultimate bearing capacity was measured as 680 kPa from the tests with Dr = 50% relative density, 48 mm length, 2% contents, and 3B depth macromesh fiber reinforced. In hybrid fibers, the highest ultimate bearing capacity was measured as 495 kPa, with Dr = 50% relative density, 48 mm length, 2% contents, and 2D depth micromesh and basalt fiber-reinforced tests. In the reinforced tests, it was concluded that the most effective fiber on bearing capacity is macromesh fiber. It can be seen that in the PIV analysis, as the fiber additive increased, the settlements made by the foundation decreased under the same pressure. It has also been observed that adding reinforcement to the soil transfers the stresses occurring in the soil to a wider area. [ABSTRACT FROM AUTHOR]

The use of fibres applied to concrete in order to improve its properties is widely known. Nowadays, research is not only focused on improving mechanical properties but also on the environmental implications. The aim of this research was a mechanical and environmental comparison between different types of fibres. For this purpose, commercial fibres of three materials were used: low carbon steel, modified polyolefins, and glass fibre. In order to improve the sustainability of the sector, we also analysed and compared the performance of using a waste product, such as fibres from machining operations on lathes. For the evaluation of the mechanical properties, compression and flexural tests were carried out. The results show that the use of low carbon steel fibres increases the flexural strength by 4.8%. At the environmental level, and in particular for impact categories such as the Global Warming Potential (GWP), lathe waste fibres prove to be the most suitable. For instance, compared to glass fibres, CO2 emissions are reduced by 14.39%. This is equivalent to a total of 38 kg CO2 emissions per m3 of reinforced concrete. In addition to avoiding the consumption of 482 MJ/m3 of fossil fuels, the results of the research indicate the feasibility of using waste fibres as a substitute for commercial fibres, contributing to an improved environmental balance without losing mechanical performance. [ABSTRACT FROM AUTHOR]

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Objective: To measure the flexural strength (FS) of bulk-fill resin composites and assess their long-term water absorption and solubility properties with and without the inclusion of short glass fibres. Methods: One resin composite, everX Flow with fibres, and four commercially available bulk-fill composites without fibres, namely, PALFIQUE, Activa, SDR Plus, and Filtek Bulk Fill One, were tested. Six specimens (2 × 2 × 25 mm) were fabricated for each material and stored in water for 1 day and 30 days to measure the flexural strength using a three-point bending test. To evaluate water absorption and solubility, circular disks measuring 15 × 2 mm (n = 5) were immersed in water for 60 days, and their weights were recorded periodically. After 60 days, the specimens were dried for an additional 21 days to determine solubility. Results: Flexural strength values ranged from 101.7 to 149.1 MPa. Significant distinctions were observed among the resin composites at the onset of the study (p < 0.05). The highest FS value was identified in everX Flow, while ACT exhibited the lowest (p < 0.05). However, the flexural strength values exhibited a significant decrease with increased storage time (p < 0.05), except for ACT, which demonstrated a noteworthy increase. Concerning water absorption and solubility, ACT displayed the highest absorption, while the range of solubility varied from −0.88 to 5.8 μg/mm3. ACT also had the highest solubility, whereas everX Flow exhibited negative solubility. Significance: The addition of short fibres, along with potential differences in matrix composition, enhanced the flexural strength of everX Flow. However, the substantial reduction in flexural strength observed in everX Flow and SDR following exposure to water corroborates the manufacturers' recommendation to apply a conventional resin composite cap on these materials. [ABSTRACT FROM AUTHOR]

Comprehending the degradation of glass fibers is crucial for service applications involving dry and wet conditions, especially when prolonged contact with water above room temperature is present. Depending on the polymer material, both thermosetting and thermoplastic matrices can permit the ingress of moisture. Therefore, fiber reinforcements embedded in the polymer matrix may experience moisture exposure. Additionally, some structural applications use fiber devoid of any matrix (dry fibers), in which water exposure must be avoided. In all of these cases, moisture may, therefore, have a significant impact on the reinforcing elements and the rate of degradation. The present work focuses on the effects of hydrothermal aging on the mechanical durability of long E-glass fibers by immersion in water at 60 °C, 71 °C, and 82 °C. A service life forecast model was created utilizing the Arrhenius technique, and a master curve of strength variation with exposure time was created for E-glass fibers at 60 °C. Using this modeling approach, it is possible to approximate the amount of time it will take to attain a given degradation level over a specified range of temperatures. Scanning electron microscopy was used to evaluate morphological changes in fiber surfaces due to hydrothermal exposure, while Fourier transform infrared spectroscopy and mass dissolution studies were used to elucidate the mechanism of the strength loss. [ABSTRACT FROM AUTHOR]

Polymethylmethacrylate (PMMA) has been the most-widely used denture base material in prosthetic dentistry for the last 80 years. It is still one of the best alternatives when new methods are inapplicable. Due to the lack of some physical inadequacies occurring during cyclic use and accidental situations, various reinforcement strategies such as using nanoparticles, wires, fibers, and meshes have been investigated and reported. In this study, it was aimed to conduct a comparative investigation of the effect of fiber additives with different characteristics on the flexural properties of heat-cured PMMA denture base resins. Glass fibers (GFs), polypropylene fibers (PPFs), and carbon fibers (CFs) having 3, 6, and 12 mm lengths and 0.25, 0.50, and 1.0% concentrations (v/v) were used for the reinforcement of PMMA denture base resins. The flexural properties (flexural strength, flexural modulus, and maximum deformation) were determined using a three-point bending test, and three-way ANOVA analyses with Bonferroni corrections were performed on the test results. The morphologies of the fracture surfaces were analyzed using scanning electron microscopy. All three fibers exhibited reinforcement in the flexural strength (p < 0.001) and flexural modulus (p < 0.001) regardless of their length and concentration. The group with 1.0% 12 mm CF-reinforced PMMA exhibited the greatest flexural strength (94.8 ± 8.8 MPa), and that with 1.0% 3 mm GFs displayed the lowest flexural strength (66.9 ± 10.4 MPa) among the fiber-reinforced groups. The greatest value of the flexural modulus was displayed by the 1.0% 3 mm CF-reinforced resin (3288.3 ± 402.1 MPa). Although the CF-reinforced groups exhibited better flexural properties, CFs are not favorable for use as reinforcement in practice due to the dark gray discoloration of the denture base resin. It was concluded that PPF is a promising material for the reinforcement of heat-cured PMMA denture base resins. [ABSTRACT FROM AUTHOR]

A new framework for the parametric reconstruction of curved fibres from glass fibre-reinforced composite X-ray computed tomography data is proposed. It allows us to detect fibres in a fibre-reinforced polymer sample from a low-dose, low resolution computed tomography scan. An efficient curve representation is then used for each detected fibre, of which the parameters are estimated directly from few 2D high-resolution projection images. The framework is validated on both simulated and real data of glass fibre-reinforced polymers. The generated results demonstrate that it is robust to noise and requires less than 10 high-resolution projections to obtain reasonable fibre estimates. The method can also improve upon existing estimation frameworks relying on full 3D scans. [ABSTRACT FROM AUTHOR]

Bismuth (Bi)‐doped glasses with broadband near‐infrared (NIR) emission have been drawing increasing interest due to their potential applications in tunable fiber lasers and broadband optical amplifiers. Yet, the implementation of highly efficient and ultra‐broadband Bi NIR emission covering the whole telecommunication window remains a daunting challenge. Here, via a metal reduction strategy to simultaneously create a chemically reductive environment during glass melting and enhance the local network rigidity, a super broadband (FWHM ≈ 600 nm) NIR emission covering the entire telecommunications window with greatly enhanced intensity was achieved in Bi‐doped germanate glasses. More importantly, due to the excellent thermal stability, the super broadband Bi NIR emission can be well retained after the glass was drawn into an optical fiber. Furthermore, the transmission loss of 0.066 dB/cm at 1310 nm and an obvious broadband amplified spontaneous emission spectrum spanning a range of 1000–1600 nm were observed in this fiber. This work can strengthen our comprehension of the complicated Bi NIR luminescence behaviors and offer a feasible and universal way to fabricate tunable fiber lasers and broadband optical amplifiers based on Bi‐doped multicomponent glasses. [ABSTRACT FROM AUTHOR]

The building sector is facing the challenge of transitioning to a more industrialized construction approach and is thus promoting the development of new materials that enable the production of lighter prefabricated products with enhanced thermal performance. This study conducts the physicochemical and mechanical characterization of a new plaster material intended for application in the building sector. The plaster material developed contains potassium polyacrylate and perlite in its composition and has been reinforced with wood, glass and polypropylene fibers to improve its physical and mechanical properties. The results demonstrate that the combined incorporation of potassium polyacrylate and expanded perlite leads to a decrease in density and thermal conductivity by 10.5% and 47%, respectively, compared to traditional plasters. In addition, the incorporation of reinforcement fibers in the plaster matrix, particularly glass fiber, improves the mechanical strength of the new material. The plaster composite developed for this research offers lightweight characteristics and improves the energy efficiency of the construction systems into which it can be integrated and is designed for use in prefabricated panels and plates especially. This progress represents a step towards more efficient industrialized construction. [ABSTRACT FROM AUTHOR]

This experimental study investigated how defects, in particular fiber misalignment, affect the mechanical behavior of glass fiber composites (GFRP) under compressive loading. GFRP cross-plies with three different types of fiber misalignment, namely a fold, a wave, and an in-plane undulation, were fabricated using the resin transfer molding process. The compressive tests were performed at four different temperatures, in order to investigate the role of a change in the matrix properties on the strength of the composite. The experiments showed that the defects, especially at lower temperatures, had a significant impact on the mechanical properties of the composite, exceeding the proportion of the defects inside the composite. With increasing temperature, the damage mechanism changed from fiber-dominated to matrix-dominated and, in doing so, decreased the significance of fiber misalignment for the mechanical behavior. [ABSTRACT FROM AUTHOR]

This paper presents results of investigation of core–clad optical fibers based on rare-earth-doped multicomponent chalcogenide glasses of the Ge–Ga(In)–As(Sb)–Se systems. Optical, emission, and lasing characteristics of such fibers in the IR spectral region demonstrate advantages of their materials over foreign analogues owing to low concentrations of regulated impurities. [ABSTRACT FROM AUTHOR]

The performance/weight ratio of fiber reinforced polymer matrix composites makes them the material of choice for structural applications in many fields such as aerospace, aeronautics, automotive and civil engineering...etc. In polymer matrix composites, the fibers used as reinforcement are mainly synthetic fibers such as carbon and/or glass fibers. To ensure the low cost of using fiber-reinforced materials in motor vehicles, it is proposed to selectively incorporate carbon fibers to enhance glass fiber composites along the roadway, and to enhance glass fiber composites along the main load path. For this purpose, we conducted a behavioral study of hybrid epoxy thermoset polymer matrix laminates to highlight the influence of alternate hybridization of glass and carbon fibers on the physical-mechanical behavior of the materials.The results obtained show that the alternated hybridation of the fibers has a significant influence on the tensile properties; and it affected the density, hardness and flexural properties significantly. [ABSTRACT FROM AUTHOR]