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Using high contents of the RAP material in newly produced asphalt mixtures leads to a reduction in the crack resistance of the mixtures. This shortcoming can be compensated using some methods such as polymer modification, rejuvenation, fibre-reinforcement, etc. In this paper, the effect of Cyclogen as a rejuvenator and glass fibre was investigated on the cracking behaviour of recycled asphalt mixtures. For this aim, the fracture energy and critical value of J integral (Jc)of semi-circular bending (SCB) asphalt specimens in terms of RAP content, Fibre content and testing temperature were investigated in this study and the results were used to develop an experimental model to predict the crack resistance of asphalt mixtures in terms of temperature and fibre and RAP content using the artificial neural network (ANN) and the multiple regression methods. The results indicated that the fracture energy and Jc valueof asphalt mixtures declined by increasing the RAP contentat intermediate temperatures. However, the reduction in fracture energy and Jc valuecould be compensated using the fibres. Both investigated models were appropriate for predicting the cracking behaviour of fibre-reinforced recycled asphalt mixtures. Nevertheless, the level of correlation was much higher for the ANN approach than the multiple regression model. [ABSTRACT FROM AUTHOR]

To rapidly repair the damaged buckling-restrained brace serving as energy absorption member during earthquake, the assembled method of wrapping the component with FRP cloth is proposed. In this research, a series of cyclic tests on six assembled buckling-restrained brace (ABRB) wrapped with three kinds of FRPs (carbon fiber, glass fiber and basalt fiber) were performed. The tested results show that all the specimens show excellent hysteretic performance and similar damage mode, namely core unit fracture, whilst short specimens show better ductility, but worse energy dissipation ability than the long specimen. A parametric analysis is performed based on a finite element model validated against the test result. The effects of the gap and friction force between core unit and infilled concrete and the thickness of FRP cloth are analyzed. The modes of multi-wave buckling of core units are exhibited, and the influence of multi-wave buckling on component performance is evaluated. Based on the test and simulation analysis, CFRP is suggested to be used in the wrapped buckling-restrained brace. [ABSTRACT FROM AUTHOR]

Polymeric materials reinforced with synthetic fibres such as glass, carbon, and aramid provide advantages of high stiffness and strength to weight ratio as compared to conventional construction materials, i.e., wood, concrete, and steel. Despite these advantages, the widespread use of synthetic fibre-reinforced polymer composite tends to decline because of their high-initial costs, their use in non-efficient structural forms, and, most importantly, their adverse environmental impact. The banana fibres were chemically modified through contact with 10 wt % sodium hydroxide solutions for 45 minutes. Polymeric composites with different fibre lengths were prepared through the hand lay-up process at room temperature. Prepared composites exhibited better mechanical and thermal properties. The tensile strength increased with an increasing fibre length of the banana fibre in epoxy matrix composites, due to the stronger interfacial interactions between the treated fibres and the epoxy matrix. These effects occurred due to the morphological and chemical changes in the treated fibre surfaces, which promote better adhesion between the fibres and the epoxy matrix. [ABSTRACT FROM AUTHOR]

This paper presents a series of single fiber pull-out tests on steel and glass fiber embedded in a cementitious matrix. First, the phase of fiber sliding in the concrete matrix was defined using a shear lag model; then, governing equations for the sliding mechanism were derived using the analytical model. FEM analysis was then used to calibrate the frictional coefficient. Further analysis related to the pressure exerted on the fiber by the surrounding concrete revealed that a smaller fiber diameter would improve bond strength. In terms of the relationship between pressure from the surrounding concrete and the diameter of the fiber, the results showed that a smaller fiber diameter would increase the matrix pressure; improved frictional bond strength and behavior would be expected compared to larger fiber diameters. The results also showed that decreasing fiber diameter by 75% would improve the frictional bond strength by as much as 300% for smooth and straight steel fiber, whereas reducing the fiber diameter by 66% would improve the frictional bond strength by 190% for single glass fibers. In addition, the results showed that a smaller diameter of the fiber improves interfacial properties between the fiber and concrete in fiber-reinforced concrete (FRC) composites. [ABSTRACT FROM AUTHOR]

An optical fiber with a high Kerr nonlinearity coefficient has been proposed and manufactured from bismuth-modified tellurite glass for creation of non-classical multiphoton states of light. Specifically, we have proposed to use these fibers to squeeze the quantum fluctuations of one of the quadratures of light in the 20 W signal significantly below –10 dB compared to the standard quantum noise limit, which is important for various practical applications. Using numerical simulation based on the stochastic nonlinear Schrödinger equation, we have demonstrated noise squeezing stronger than –16 dB at tellurite fiber lengths of 6–14 m, while in squeezing of –14 dB is expected in silica glass fibers having lengths of 120–300 m. Analytical formulas were used to analyze the physical factors that limit the achievable squeezing. [ABSTRACT FROM AUTHOR]

Rock fiber is a suitable alternative material to replace traditional glass fibers used in many applications, and so many manufacturers and suppliers around the world are interested in rock fiber. The geochemical properties of rocks to be used in fiber production are of great importance. Some technological evaluation criteria have been proposed previously according to the geochemical properties of the related natural materials. In this study, a single parameter, namely the Differentiation Index (DI), calculated with normative mineral abundances, is proposed against four parameters [total acidity coefficient (Ktotal), total acidity modulus (Mtotal), acidity modulus (Ma), viscosity modulus (Mv)] used in previous studies to determine which type of fiber the rocks are suitable for. In addition, we compared the chemical compositions of the selected volcanic rocks from Sivas and Kayseri provinces (Central Anatolia, Turkey) with those of reference rocks from the literature. Sivas samples are dominantly silica-undersaturated, whereas Kayseri samples are silica-oversaturated with frequent silica-saturated samples in both groups. Mineral norms correlate well with modal abundances of nepheline in Sivas samples, indicating the calculated degrees of silica saturation is representative. The DI shows significant correlation with the four parameters and it distinguishes the reference rocks according to the fiber type to be produced. As a result of the evaluation made using the reference rocks employed in this study, we suggest that the 35–50 DI range represents rocks suitable for continuous fiber production, and rocks with DI of < 35 may be ideal for the production of staple fiber. According to the ranges of DI, while most of the Kayseri samples are recommended for continuous fiber production, both types of fibers can be produced from Sivas lavas. [ABSTRACT FROM AUTHOR]

[Display omitted] Materials made of synthetic vitreous mineral fibers, such as stone wool, are widely used in construction, in functional composites and as thermal and acoustic insulation. Chemical stability is an important parameter in assessing long term durability of the products. Stability is determined by fiber resistivity to dissolution, where the controlling parameters are solid surface area to solution volume ratio (S/V), pH and composition of the fibers and organic compounds used as binders. We investigated stone wool dissolution under flow through conditions, far from equilibrium, at pH range of 2 to 13, as well as under batch conditions, close to equilibrium, for up to 28 days, where S/V ranged from 100 to 10000 m−1. The dissolution rate of stone wool shows minimum at pH 8.5 and increases significantly at pH < 4.5 and pH > 12. In close to equilibrium conditions, S/V defines the steady state concentration for the leached components. Decreased dissolution rate could result from evolution of a surface leached layer or the formation of secondary surface phases or both. We suggested three dissolution rate controlling mechanisms, which depend on pH. That is, dissolution is controlled by: a SiO 2 rich surface layer at pH < 4.5; by adsorption of an Al and Al-Si mixed surface layer at 5 < pH < 11 and by divalent cation adsorption and formation of secondary phases (silicates, hydroxides) at pH ∼ 13. The organic compounds, used to treat the stone wool fibers during manufacture, had no influence on their dissolution properties. [ABSTRACT FROM AUTHOR]

This paper investigates the behaviour of the hybrid fibre, i.e. a combination of E glass and basalt fibre, added in the reinforced concrete column. A total of 6 columns were cast with Conventional Concrete (CC) and Hybrid Fibre Reinforced Concrete (HFRC) to study the structural performance of the column. The concrete was made of cement, manufacturing sand (m-sand), coarse aggregate as major ingredients. In the column, 2% of Basalt fibre along with the E-Glass fibre of 1% were added to the concrete to make the HFRC. Column was tested under universal testing machine with static axial load and deflectometer was placed at the sides of the column to measure the displacement. The axail and laterall deformation of the column was measured using the deflectometer. The strain of the column was determined with the recorded data. The stiffness of the column with respect to the loads was calculated. The lateral buckling of the CC and HFRC columns were calculated and compared. Both CC and HFRC shows a similar mode of failure with the application of the load. The experimental results of the columns were compared with theoretical value and concluded with the performance column with and without fibre added. [ABSTRACT FROM AUTHOR]

Fibre is a small piece of reinforcing material possessing certain characteristics properties, which is circular or flat in shape. Hybrid Fibre Reinforced Concrete (Hy-FRC) is formed from a combination of two or more different types of fibres, which differ in material properties, remain bonded together, when added in concrete and retain their identities and properties. The combining of fibres, often called hybridization, which is here investigated for a M20 grade concrete. In this experimental study, two different fibres namely Polypropylene of 1.5% and Glass fibre of 0.5%,1% and 1.5% were replaced with weight of cement. The compressive, tensile and flexural strength of the concrete increases due to better load transfer within the fibres. The usage of fibres decreases the porosity of the concrete. The deflection of the concrete member will be comparatively minimal due to increase in tensile strength of concrete. The hardened and durability properties on concrete were done on various concentration of hybrid fibres mixed concrete and results were discussed. [ABSTRACT FROM AUTHOR]

An innovative glass fiber reinforced polymer (GFRP) closed-type winding (GFRP-CW) tie was developed to eliminate the bond slip failure and make full use of the tensile strength of ties compared with conventional pultruded fiber reinforced polymer (FRP) rod ties. Although better confinement effect of GFRP-CW ties, however after spalling of concrete cover, the compressive longitudinal FRP bars in the plastic hinge regions of columns are most likely to crush or buckle. External FRP jackets can effectively restraint damage to concrete cover. Against this background, a novel FRP-reinforced concrete column confined with external FRP jackets and the internal GFRP-CW ties were proposed to prevent the FRP bars from premature buckling or crushing. In this article, twelve square new columns were constructed and tested to characterize the axial compressive behavior. The test parameters included FRP wrapping type (GFRP or carbon fiber reinforced polymer (CFRP)), FRP wrapping layers, and spacing of ties. Test results confirmed that FRP-reinforced concrete columns with external FRP jackets had significantly larger ductile behavior and exhibited higher load-carrying capacity than their counterparts FRP-reinforced concrete columns due to the contribution of longitudinal GFRP bars and the concrete cover. The test results also suggested reasonable spacing of ties and layers of GFRP jackets for an expected moderate confinement behavior. [ABSTRACT FROM AUTHOR]

The use of additive manufacturing has been widely developed in the industry due to its ability to make complex shapes. The use of reinforcing fibers has provided a wider design capability in this field. Due to the effect of the number of fibers reinforced used on the mechanical properties, the study of the obtained mechanical properties is of great importance. This paper presents the experimental findings of tensile loading and three points bending fatigue tests performed on polymer-based composites (Onyx (which is CF-PA6) and reinforced Onyx with continuous glass fiber (CF-PA6 + GF) using Fused Filament Fabrication. Tensile properties of various types of printing conditions (Solid, Triangular, Rectangular, and Hexagonal fill patterns) have been compared. The coupled frequency amplitude affects the nature of the overall fatigue response which can be controlled by the damage mechanisms accumulation and/or by the self-heating. For fatigue loading, self-heating has been observed and yielded a temperature rise to about 60°C which is more than the glass transition temperature of the polymer. Multi-scale damage analysis of the sample in fatigue showed that the first observed damage phenomenon corresponds to the debonding of the filaments which leads to the propagation of transverse cracks. [ABSTRACT FROM AUTHOR]

The purpose of this work is to fabricate and analyse a light weight, recyclable, and non-toxic natural fiber reinforced industrial safety helmet. The fibers were extracted from agro-waste pseudostem of nendran variety banana plant. A facile needle punching technique was employed on banana fibers to produce a needle punched non-woven banana fiber fabric of enhanced mechanical properties without any chemical treatment. Subsequently, the needle punched banana fibers were impregnated with general purpose helmet grade polyester resin in an ISI (Indian standards Institute) endorsed mold to fabricate a needle punched banana fiber helmet (NPBFH). Similarly, 30 mm random banana fiber helmet (RBFH) and glass fiber reinforced helmets (RGFH) were fabricated. The fabricated helmets of 10–50 wt. % fiber content were tested as per ISI standards. The results show that the better properties were achieved at 40 wt. % of fiber content for all varieties of helmets. Significantly, the results revealed that the shock absorption, penetration resistance, and water absorption of NPBFH are 245 kgf, 4.75 mm, and 0.61%, respectively, which is much better than RBFH and comparable with RGFH. This study concluded that the NPBFH (40 wt. %) can be a potential replacement of synthetic fiber reinforced helmets for industrial applications. [ABSTRACT FROM AUTHOR]

Rapid prototyping (also known as additive manufacturing, AM) is a quickly developing process with increasing new applications in a large variety of industrial sectors (i.e., aerospace, automotive, medical, among others.) However, despite the great advantage of a decoupled price to part complexity of an AM fabricated structure, the material properties (largely governed by filament material and printing parameters) still present a significant limiting factor. In this context, the development of new filament materials for a wider range of applications has great potential. In this study, the influence of micro-scale filler reinforcement (powders), both natural (curauá) and synthetic (glass fibre), in the fabrication of an Acrylonitrile Butadiene Styrene (ABS) filament was evaluated. The filler was controlled by weight fraction (~1%) and the filament was fabricated via extrusion. A commercially available 3D printer was used to print tensile and flexural specimens for mechanical characterization as per ASTM standards. The fracture morphology was analysed after tensile testing via optical microscopy in order to evaluate the effect of the fillers on the material deposition and void formation. No significant variation in the tensile properties was reported, except for the strain at failure, while more significant flexural strength variation was observed as a function of filler material. The fillers presented a significant effect on the void density of the fractured surface. It was demonstrated that this simple fabrication technique can generate novel filament materials that may enhance the mechanical properties or widen the range of application (e.g., faster decomposition times in nature for singleuse plastics due to the hydrophilic nature of the natural filler and lower water absorption of the hydrophobic synthetic filler for marine environment applications). [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The thermomechanical properties of short glass fiber (GF) reinforced polypropylene random copolymer (PPR) composites are investigated. Four composites with different fiber content, namely 10, 15, 20, and 30 wt%, are prepared using melting mixing. For fibers up to 15 wt% the composites exhibit enhanced thermal stability as compared to the random polypropylene. The use of fibers also improve the mechanical strength of the matrix. In particular, PPR/GF30% demonstrates the highest Young modulus, yield strength, and storage modulus values, while PPR/GF10% has the best ductility among the composites. Incorporation of 10 wt% fibers also increases the yield strength and storage modulus of the PPR matrix by approximately 1.6 and 1.2 (for temperatures higher than 60°C) times, respectively. These results suggest that GF reinforced PPR is a composite suitable for advanced technological applications. [ABSTRACT FROM AUTHOR]

The demand for durable and sustainable eco-friendly materials in recent times has caused many researchers to consider the use of plant fibers in composite development. In this research, the suitability of treated pawpaw fiber as a substitute for glass fiber was considered. The pawpaw fiber was extracted from the plant stem by dew retting and treated before been incorporated into the epoxy matrix. Two distinct fiber structures in linear and network forms were identified, separated, and used for the development of the composites. The composites were produced by incorporating a fixed amount of pawpaw fiber with a varied amount of glass fiber within 3–15 wt% in epoxy-based polymer matrix after which mechanical and biodegradation tests were carried out on the developed samples. Fractured surface morphology was also observed using a scanning electron microscope. The results revealed that the fiber structures influence the properties of the material. While mechanical properties were mostly enhanced by treated linear structure pawpaw fiber, biodegradation was highly promoted by treated network structure pawpaw fiber. Tensile (except for strain), hardness, and flexural properties were enhanced by the linear-structured treated pawpaw fiber, while biodegradability, impact, and tensile strain were improved by the network-structured treated pawpaw fiber compared to the control sample. [ABSTRACT FROM AUTHOR]

The existing version of Alloy was available on the market with CAD using CATIA V5 software. Finite element Separation and analysis are performed using the CATIA V5 package. FEA has helped to identify areas with greater potential for objects and has also identified areas that can be changed and a well-designed model can be found. In this work, small defects occur in the composite phase of E-Glass Fiber Glass Fabric, also this small modulus is 0.04x109n / m2. This work provides a comparative analysis of the various types of carbon-composite materials for alloy wheel construction. [ABSTRACT FROM AUTHOR]

The nanoparticles are incorporated into the composite to mark their unique properties. This work investigates the hybrid epoxy nanocomposite and the impact of nanographite reinforcement. The composite was prepared by using a mechanical stirring technique. The amount of nanographite was added in different volumes, i.e., 1.0, 1.5, and 2.0 wt.%. Results of mechanical and dynamic loading properties were analyzed in accordance to the quantity of nano-G. The fiber and matrix interfacial bonding enrichments were evident in high-resolution SEM images-tensile fracture surface. Finally, the optimum content of nanoparticle which impacts the sample greatly was found to be 1.5 wt.%. [ABSTRACT FROM AUTHOR]

In this study, a total of 105 shear specimens of fiber reinforced polymer bars with different reinforced phases, including the glass fiber, the hybrid of carbon fiber with glass fiber, and the hybrid of steel wire with glass fiber, were prepared to systematically investigate their transverse shear properties. The surface configuration of specimens, the performance characteristics and distribution pattern of reinforced phase were mainly regarded as variables. The results showed the shear strengths of glass fiber reinforced polymer bar specimens increased from 247.9 MPa to 263.5 MPa as the rib depth changed from shallow ribs to deep ribs, and their ultimate strain decreased from 0.374 to 0.328 with the increase in rib spacing from 8 mm to 16 mm. The shear strengths of carbon/glass hybrid fiber reinforced polymer (C/G HFRP) bar specimens declined from 247.4 MPa to 226.3 MPa as the distribution pattern of carbon fiber changed from centralized distribution to dispersed distribution. The shear strength of C/G HFRP bars decreased from 256.5 MPa to 247.4 MPa as the ratio of glass fiber to carbon fiber ranged from 0:1 to 1:4, and increased from 138.7 MPa to 214.8 MPa for steel wire/glass HFRP bars as the volumetric fraction of steel wire replacing glass fiber increased from 0 to 33.3%. This indicated that the surface configuration of specimen, the distribution pattern of fiber, and the performance characteristics of reinforced phase have great effects on the ultimate strain and shear strength of FRP bars, respectively. [ABSTRACT FROM AUTHOR]

Continuous glass fiber reinforced polylactic acid (CGF/PLA) composites were prepared by 3D printing technology in this study. The multi‐roll melt impregnation mold was manufactured according to the melt impregnation model. CGF/PLA filament was prepared by a melt impregnation device, and then used to prepare CGF/PLA composite materials by the self‐modified 3D printer device. The full impregnation of the fibers was achieved by the action of the coverage angle of the tension roller in the impregnation mold. The effects of the total coverage angle, traction speed, fiber content, and impregnation temperature on the fiber impregnation effect and 3D printed product performance were studied. The bending strength, tensile strength, impact strength, and interlayer shear strength of the printed sample reached 312, 220, 154, and 14 MPa, respectively. The strategy in this study can effectively improve the impregnation effect of PLA resin on CGFs and promote the development and application of 3D printing technology in the field of high‐performance composite manufacturing. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: This ex vivo study aimed to evaluate the strengthening effect of different ferrule and reattachment designs with fiber and adhesive materials on vertically fractured teeth. Methods: Ninety extracted single-root premolars were instrumented and divided into nine groups (two control groups and seven experimental groups; n = 10). The negative control (NC) group comprised of intact teeth, while the positive control (PC) group comprised of root canal-treated teeth. The roots of the teeth in the experimental groups were vertically fractured into two equal fragments. The fragments were reattached with one of the followings: 4-methacryloxyethyl trimellitate anhydride/methacrylate-tri-n-butyl borane (4-META/MMA-TBB) resin, 4-META/MMA-TBB + quartz fiber post, 4-META/MMA-TBB + glass fiber bundles, 4-META/MMA-TBB + quartz fiber post + 1 mm ferrule, 4-META/MMA-TBB + glass fiber bundles + 1 mm ferrule, 4-META/MMA-TBB + quartz fiber post + 2 mm ferrule, and 4-META/MMA-TBB + glass fiber bundles + 2 mm ferrule. The core build-ups were made with composite resin. The specimens were subjected to compressive loading until failure occurred. Mean load necessary to fracture each sample and the fracture types of these samples were recorded. Results: The highest mean fracture load was recorded in the NC group (1,036.7 N), which was not significantly higher than the PC group (989.66 N) (p > 0.05). The roots reattached with quartz fiber post demonstrated significantly less fracture strength (871.9 N) as compared to the other test and control groups (p < 0.05). There was no significant difference between the PC group and reattached fragments with different ferrule designs in terms of fracture resistance (p > 0.05). Conclusions: The customized fiber bundles may be more suitable for reattachment of vertically fractured teeth than the rigid fiber posts. For reattachment procedures, the ferrule design may be preferred to increase the fracture strength of vertically fractured teeth. [ABSTRACT FROM AUTHOR]

Further attenuation of Rayleigh scattering of silica glass is required to extend the capacity of long‐distance optical fiber communication. To theoretically examine the effect of aluminum and fluorine co‐doping on the density fluctuations of silica glass, which is related to Rayleigh scattering, a set of force‐matching potentials (FMP) for simulating F‐doped aluminosilicates was developed using Bayesian optimization based on density functional theory calculations. Molecular dynamics (MD) simulations with the new FMP could evaluate the densities of silica glasses to which a small amount of fluorine was doped and those of aluminosilicate glasses with a wide range of aluminum contents within reasonable accuracy. The FMP successfully represents the changing role of aluminum from a network former without a compensating cation (threefold coordination) to that with a compensating cation and a charge compensator in the aluminosilicates. Indeed, relative concentrations of four, five, and sixfold‐coordinated aluminum observed by NMR measurements were reproduced better than the original Teter potential at a high aluminum content. At an aluminum content lower than 1 mol%, threefold‐coordinated aluminum was observed, which is consistent with ESR measurements. After careful validations of the FMP, the effect of the co‐doping of alumina and fluorine on the density fluctuations of silica glass was computationally examined. Consequently, it was expected that the co‐doping might not sufficiently attenuate the Rayleigh scattering, even though 1 wt% fluorine would be able to reduce the density fluctuations of aluminosilicate glasses for some extent. This is because more alumina‐doping increases density fluctuations of silica glass if the drawing temperature and procedure are the same with those for silica glass fiber. Thereby, a possible fabrication process to sufficiently attenuate the Rayleigh scattering of the F‐doped aluminosilicate glass was proposed, according to the density fluctuation analysis at high temperature. [ABSTRACT FROM AUTHOR]

The increasing demand for lightweight and economical automotive components boosts investigation of advanced materials and new lightweighting technologies. This work employs the novel microcellular injection molding technology Ku-Fizz™. The process introduces gas with granulates at moderate low pressures into the feed zone of the injection molding machine. Ku-Fizz is controlled by gas pressure; thus, a simple plate geometry was molded and the effect of various gas contents on the microstructure was analyzed. The material used was a chemically coupled glass fiber-reinforced polypropylene compound. Optical microscopy was employed to measure the foam microstructure. Microcomputed tomography was used to quantify the fiber volume fraction and the orientation tensors. Results of the fully characterized microstructure showed cell density increasing and cell size decreasing with gas pressure and melt flow direction. Fiber length increased with gas content. Cell growth displaced fibers from the center of the part towards the mold surface, changing the fiber concentration and global fiber orientation. [ABSTRACT FROM AUTHOR]

The reinforcement efficiency on a composite depends on the effective transfer of the stress between matrix and fiber. This work presents an experimental and comparative study of fibermatrix bond strength for fiber-matrix interface between glass fibers and carbon fibers added to the slag-based geopolymer matrix. This analysis was performed by pull-out test. A total of 18 tests have been conducted, three for each type of fiber at each embedded length of 10mm, 20mm and 30mm. The critical embedded length and the maximum interfacial shear (bond) strength were analyzed, and SEM observations were carried out for the cross-section of each fiber to measure diameter and observe the interface. It was found that the greatest efficiency was obtained by reinforcing with the glass fibers, incorporated at 20mm in the slag-based matrix. [ABSTRACT FROM AUTHOR]

In this paper, we present a new series of alkali‐free bioactive glasses (BG) based on FastOs® composition (38.49 SiO2 – 36.07 CaO – 19.24 MgO – 5.61 P2O5 – 0.59 CaF2, expressed in mol %), which was modified by partially replacing silicon dioxide network‐former with boron trioxide network‐former, utilizing calcium oxide as a charge compensator. The main objective of this study was to obtain a new family of bioactive glasses suitable for the fabrication of glass fibers. The BGs were prepared by melt quenching technique and their structural and thermal properties were determined. Glass rods were used to obtain fibers by the classic drawing technique. The bioactivity of the fibers was subsequently assessed through immersion tests in simulated body fluid (SBF) to establish their ability to form hydroxyl carbonated (HCA) apatite onto their surfaces. Glasses with moderate substitution of SiO2 with B2O3 exhibited enhanced thermal properties, allowing to significantly suppress the crystallization trend, and favoring to draw the fibers. The structure of the studied glasses was obtained by NMR spectroscopy. The structure‐property correlations were established by their relationship to the configurational entropy. Smaller amounts of substitution resulted in larger entropy of the glasses. Moreover the SBF tests revealed an extensive formation of HCA, comparable to the parent FastOs®BG composition, which assures fast bonding to the bone. Thus, presented glass fibers may be considered as promising materials for wool‐like bone implants or as reinforcing constituent of biopolymer matrix composites. [ABSTRACT FROM AUTHOR]

Cementitious materials are quite possibly the most normally utilized and essential materials in the building area. From the get-go in the restoring cycle, these cement-based materials might be effectively handled and framed into the suitable indicated structures and underlying designs. In any case, the fragility of these cement-based materials, alongside their hardened attributes, is liable for the advancement of cracks just as their proliferation when exposed to pressures. A particularly flimsy spot makes the materials' mechanical qualities fall apart, inferring exorbitant upkeep or maybe rebuilding of such materials in a generally short life expectancy. Thus, new cement-based materials with further developed durability characteristics, for example, crack opposition, are needed in the development area. Fiber built up concrete has been eliminated for customary concrete, which is a delicate material. Albeit the utilization of a solitary kind of fiber can work on concrete's mechanical attributes, hybridization can make up for the deficiencies of two fiber types and address their advantages. In this proposition, the impact of using glass fiber and polypropylene fiber for supporting concrete is examined to quantify the mechanical qualities of the concrete lattice. For this reason, 15 3D shapes and 15 chambers of glass fiber supported concrete (GFRC) with various rates (0.2 percent, 0.4 percent, 0.6 percent, 0.8 percent, 1.0 percent, 1.2 percent) in volume of M30 grade concrete were projected in the wake of restoring examples were inspected for greatest compressive and rigidity got at 1%. In the wake of accomplishing greatest strength at the ideal measurement of glass fiber, 3D squares and chambers are projected with different rates of polypropylene fiber while keeping the glass fiber steady, bringing about the ideal dose of mixture fiber built up concrete strength of 1% glass and 0.6 percent polypropylene fiber. The proper portion of filaments is utilized to decide the flexural strength (70cm X 10cm X 15cm) and shear (100cm X 10cm X 15cm) of Hybrid fiber built up concrete (HFRC). When contrasted with Nominal concrete, the test discoveries show that the half breed type of fiber upgrades compressive, tractable, flexure, and shear esteems. [ABSTRACT FROM AUTHOR]

The unified effective stress theory based on suction stress (SSCC theory) enables the characterization of soils under both saturated and unsaturated conditions with one closed-form relationship. This study provides experimental verification of this theory through the unconfined compressive strength test (UCS) and indirect tensile test strength (ITS) on silty clay soil stabilized with fiber. A series of matric suction, ITS, and UCS tests were conducted to validate the SSCC theory through the representation of the results of ITS and UCS tests in terms of mean total stress (p) versus deviatoric stress (q) and mean effective stress (p') versus deviatoric stress (q). The results of the validation procedures showed that the SSCC theory is applicable and valid at a range of 6%–16% of water content on the silty clay and the silty clay fiber-reinforced soils. There is a small fluctuation in the increase of ITS and UCS values with increasing fiber content due to randomly oriented distribution of the fiber. The addition of glass fiber does not significantly affect the capacity of water retention of the soil. It improves the condition of the mechanical soil properties at the end of construction more than of the effective stress condition. [ABSTRACT FROM AUTHOR]

Increasing environmental concern has put forward the use of flax fibers instead of glass fibers in composite materials. However, durability performances of these bio-fibers remain one of their main issues. This study focuses on the hydrothermal aging of flax fibers. Flax tows were immersed in distilled water at a temperature of 80 °C for different durations. The effect of the hydrothermal aging on mechanical properties of flax tows was evaluated. Results showed a strong decrease in the maximal strength and the stiffness by 31% and 49%, respectively, until one week of aging. Multi-scale analyses were realized to explain these evolutions. Morphological characterization highlighted a washing of fiber surfaces during the hydrothermal aging, extracting amorphous components as pectins, lignins and amorphous hemicelluloses from cortical tissues. We showed that this morphological evolution impacted the fiber crystallinity. Based on a mechanical analysis, we showed that amorphous components extraction may be at the origin of the material softening. Moreover, the amorphous phase in particular the natural binder pectin would play a major role in the fiber stiffness but does not modify the flaws at the origin of failure. [ABSTRACT FROM AUTHOR]

The stress interaction failure criterion was applied to three compression‐molded sheet molding compound (SMC) materials. Two are epoxy‐based compounds with randomly oriented carbon fiber tows, and the third material consists of glass fiber bundles randomly oriented in a vinyl ester resin. The failure surface was built using tensile test results at different orientations with respect to the flow direction, resulting in combined loads in the principal stress coordinate system. Three unknown variables arise from using only tensile strength values. Solving a system of three equations derived from the criterion function and using the failure values obtained from destructively testing at three different orientations, the unknown variables as well as the interaction strength components were determined. Results show good agreement for all three materials. Overprediction was found in some instances, attributed to the effect of fiber orientation distribution in the part, and to the complex interactions of the filled structures. To allow a more direct comparison between predicted and experimental data, the resulting failure surface was translated to the global coordinate system (σxx) and compared to the data derived from destructive tensile tests. Good agreement for all materials was observed, with underprediction noted for some orientations, attributed in part to the equation solving method and the nature of the mesostructures of the composites, where interactions between the tows, resin, mold walls, and fibers are present. The results of this work show that the methodology described permits the development of a failure surface for SMC materials when limited data is available. [ABSTRACT FROM AUTHOR]

The increasing demand for vehicles is resulting in environmental problems, such as a higher demand for fossil fuels and higher CO2 emissions. Lightweight materials, such as fiberreinforced polymers, have been used in automotive components to reduce the weight, fuel consumption, and CO2 emissions of vehicles. Natural fibers are often used as substitutes for glass fibers because they are abundant and require less energy to produce compared to glass fibers. The present research focused on the preparation and characterization of composites reinforced with Sansevieria trifasciata fiber (STF). High-impact polypropylene (HIPP) and vinyl ester (VE) were chosen and compared as matrix materials. The results showed that the mechanical properties of the produced biocomposites increased with increasing amounts of fiber, alkaline treatment, and unidirectional fiber orientation. A tensile strength of 59.77 MPa and a stiffness of 1.97 GPa were obtained for STF/HIPP composites with unidirectional alkali treatment and a 15% volume fraction of fiber. Moreover, a tensile strength of 121.1 MPa and a stiffness of 7.65 GPa were obtained for STF/VE composites with unidirectional alkali treatment and a 15% volume fraction of fiber. The STF/VE biocomposites were comparable to commercial glass fiber composites for automotive applications and even exhibited greater tensile strength properties. [ABSTRACT FROM AUTHOR]

The durability of the notch and un-notch composites is mainly affected by environmental ageing, the condition of mechanical loading and mechanical ageing. Due to the dissimilarity of two components of fibre mat-reinforced thermosetting composites (e.g. fibre and resin), thermal stress and strain can be generated and raised by moisture, temperature variation, thermal ageing and mechanical ageing in any working environment. This study aims at investigating the effect of thermal ageing fatigue and mechanical ageing fatigue on the mechanical durability and notch sensitivity properties of glass fibre mat unsaturated polyester resin composites and kenaf fibre mat/unsaturated polyester composites. Tensile tests of smooth and notched specimens, low cycle tensile fatigue tests, dynamic mechanical analysis, stress distribution by point-stress failure criteria and notch sensitivity analysis were performed to both types of the specimens. Both composites were previously taken under up to 100 number of freeze-thaw ageing cycles (from −25 to + 58℃). It is found that the tensile modulus and un-notched strength of kenaf fibre mat/unsaturated polyester were decreased by 30 and 27%, respectively, which was more severe than that of glass fibre mat/unsaturated polyester composites. After the thermal ageing, notch (open hole) did not diminish the strength property of kenaf fibre mat/unsaturated polyester, and there was an absolute increase of characteristic distance (d0) which indicates the lower notch sensitivity of kenaf fibre mat/unsaturated polyester. Although glass fibre mat/unsaturated polyester had superior mechanical properties, after thermal ageing, while kenaf fibre mat/unsaturated polyester presented stable low cycle fatigue property, better energy absorption and notch sensitivity properties. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Various approaches to reduce the weight of electronics and automobile devices have been explored. For instance, an alternative polymer was utilized to replace metals. In the present study, a new circular braided glass fiber/epoxy composite (braid angle: 45°, fiber: 48 vol%) with a helical structure was fabricated as a model coil spring for weight reduction. A plaster‐sacrificial compression mold was especially designed to fabricate helical composites without voids. The spring design was validated by the experimental results of torsional tests. Plastic deformations of the epoxy resin were measured using creep tests to eliminate high‐temperature plastic deformation (HTPD) of the composites. Pre‐strain applied thermal aging was utilized to remove HTPD. Mechanical properties of the composites were also investigated. The mechanism of mechanical failure was found to be the interfacial failure. For preparation of uncured prepreg, resin permeability was measured to a range of 10−10 m2. Resin transfer in the glass fiber‐braided textiles occurred due to the combination of viscous and diffusional flow mechanisms. Based on the results in this study, the facilely designed coil spring composite can be used for various applications, especially automotive parts. [ABSTRACT FROM AUTHOR]

A comprehensive study was performed of various types of aluminum-containing raw materials and their effect on glass formation during smelting of borosilicate glasses for type-E fiber. It is shown that on use of non-metallurgical alumina, as compared with metallurgical alumina, disthene-sillimanite concentrate, and kaolin, a savings of energy resources for glass formation processes from 2.64 to 16.30% obtains. [ABSTRACT FROM AUTHOR]

In the family of polyimide (PI) materials, Upilex-S® film has been a shining star through the research PI materials due to its appealing merits. Unfortunately, the wholly rigid-rod backbone and easily formed skin-core micromorphology and microvoids of Upilex-S® type PI lead to the high difficulty in melt- and wet-spinning fabrication. Herein, we propose a facile and scalable method, reaction-spinning, to fabricate the Upilex-S® type PI fiber, in which the rapid solidification of spinning dope and partial imidization take place simultaneously. Thus, the stability and mechanical strength of as-spun fibers can be improved, and the microvoids in fibers can be greatly reduced in relative to the wet-spun fibers. The resultant Upilex-S® type PI fiber shows higher tensile strength and modulus than most commercial thermal-oxidative polymeric fibers with an ultrahigh glass transition temperature Tg of 478 °C. Moreover, the WAXS and SAXS results indicate that orthorhombic crystals are formed for Upilex-S® type PI fiber in the post hot-drawing process. Increasing the hot-drawing temperature results in a continuous crystallization and high orientation of PI chains in amorphous phase and perfects the existing lamellar structure, which make a great contribution to the improved mechanical property. [ABSTRACT FROM AUTHOR]

A change in the length distribution of glass fiber was induced by mixing long glass fiber 30%‐ reinforced polypropylene composites with recycled composites of short glass fiber 30%‐reinforced polypropylene, and the improvement in mechanical properties was investigated. Changes in mechanical properties were confirmed as a function of the number of recycles and mixing ratio of the composites, and the average fiber length and length distribution of the glass fibers were analyzed using a three‐dimensional measuring machine. The tensile strength, flexural strength, flexural modulus, and impact strength of the blend of a once‐recycled composite of short glass fiber‐reinforced polypropylene and once‐recycled composite of long glass fiber‐reinforced polypropylene in a ratio of 40:60 were 99%, 102%, 100%, and 100% those of a virgin composite of short glass fiber‐reinforced polypropylene, respectively. In addition, the average length of the glass fiber of this blend was 0.305 mm, which was similar to that of the virgin composite of short glass fiber‐reinforced polypropylene (0.313 mm); furthermore, the distribution ratio of long fibers of length 1 mm or more was 5%. The length distribution of the glass fibers was significantly altered by the combination of the recycled composites and the long glass fiber‐reinforced composite; accordingly, the deteriorated mechanical properties of the recycled composites could be significantly recovered. [ABSTRACT FROM AUTHOR]

Different methods were used to treat the fiber posts and root canals, and evaluated their influence on the bond strength of fiber posts. After thirty extracted human, single-rooted premolars were endodontically treated and post space was prepared in each tooth with post drills, they were randomly assigned into nine groups with 33 fiber glass posts. Different treatment methods for fiber posts and root canals were applied. Following post cementation, slice specimens were prepared. The push-out test was performed using a universal testing machine, and the failure modes were examined with a stereomicroscope. Bond strengths (mean ± SD) were: CC group (7.07 ± 1.51 MPa); CE group (10.57 ± 2.90 MPa); CM group (10.06 ± 3.00 MPa); SiC group (7.23 ± 2.06 MPa); SiE group (10.51 ± 2.26 MPa); SiM group (10.50 ± 2.70 MPa); PC group (9.79 ± 2.79 MPa); PE group (11.70 ± 1.76 MPa); PM group (11.06 ± 3.17 MPa). The bond strength of polydopamine group was significantly higher than silane group and control group (p < 0.05). NaClO/EDTA group had higher bond strength than the MTAD group, and both were higher than the control group (p < 0.05). Combined treatment of fiber post and root canal was more advantageous to improve the bond strength between fiber post and root canal. Surface polydopamine functionalization was confirmed to be a reliable method for improving the bond strength of fiber posts. The effect of 5.25% NaClO + 17% EDTA solution on the bond strength is more significant than MTAD solution. When the fiber posts were treated with PDA and the root canals were treated with NaClO/EDTA, the best bond strength can be obtained. In this experiment, fiber posts and root canals were treated separately. The aim of this paper is to explore the influence of different treatment methods on the bond strength of fiber posts, in order to screen out the most effective processing methods and provide theoretical guidance for the clinical application. [ABSTRACT FROM AUTHOR]

In this study the experimental investigation of mechanical behaviour of Multi-Walled Carbon nanotubes (MWCNTs) and Aluminium Oxide (Al2O3) reinforced with EGlass/ Epoxy nanocomposites at 0.5%, 1.5% and 2.0% of weight rated with 225 GSM, 300 GSM and 450 GSM glass fibres were studied. Test specimens were prepared at the standardof ASTM D638 for tensile specimen ASTM D256 for impact specimen. Testspecimens were prepared at the ratio of MWCNTs: Al2O3 is 1:4. 1.5 wt. % of Multi- Walled CNTs filledE-Glass/Epoxy nanocomposites showed improved mechanical properties than glass fiber reinforced epoxy composites.450 GSM reinforced glass fiber epoxy composites containing 1.5wt. % of MWCNTs improved 36.27 % of higher tensile value and 28.57 % of impact value than the glass fibre reinforced epoxy composites. 225 and 300 GSM reinforced glass fibre epoxy composites with 1.5 wt. % of MWCNTs composites also has improved tensile and impact value than glass fibre reinforced epoxy composites. But, overall 450 GSM reinforced fibre nanocomposites showed enhanced mechanical properties than the other GSM reinforced nanocomposites. This proves Multi- Walled Carbon Nanotubes is a successful reinforcement for E-Glass/Epoxy matrix and it improves its properties and performance. [ABSTRACT FROM AUTHOR]

• G2 glass matched with F2 glass (Schott) was used to draw fiber. • A linear increase and efficient response at 374 nm were obtained in G2 glass with X-ray radiation. • G2 glass material has an ideal and stable optical response. • G2 glass fiber has an emission at about 375 nm and a short fluorescence lifetime (2.22 ns). In order to enrich the application demands of neutron detection field, this study prepared a series of Ce3+/Gd3+ co-doped borosilicate scintillating glass materials. The ultraviolet (UV) absorption edges were all below 400 nm. The optical band gap was shortened from 3.48 eV to 3.24 eV as well as the optical basicity increased from 0.4941 to 0.5063 with the added concentration of Gd3+ ions. When the samples were excited by a 330 nm light source, the central wavelength of the emission spectra was 375 nm. The fluorescence lifetime of the sample was 30.99 ns. The emission intensity of the G2 sample increases linearly with the increase of X-ray excitation current, and has a stable optical response at 374 nm. The G2 glass fiber with the highest fluorescence intensity had a prominent emission peak at 375 nm and the fluorescence lifetime of 2.22 ns. [ABSTRACT FROM AUTHOR]

Long fibre reinforced thermoplastics (LFTs) have become important in recent years, due to outstanding mechanical properties (such as high strength, high stiffness, and excellent impact behaviour). Nevertheless, there is still a lack of knowledge regarding the failure micromechanics of LFTs. This publication focuses on the qualitative and quantitative analysis of influencing factors for failure initiation in long fibre reinforced thermoplastics. Existing and new methodologies are combined for detailed analysis of the local microstructure and micromechanical behaviour. In situ investigations of the LFT via X-ray computed tomography (CT) and subsequent fibre and mechanical characterization based on the volume data were performed. A measurement workflow for the decision on the scanning area before starting a scan series is suggested. The difficulties in fibre orientation analysis of long, curved fibres are revealed by a comparison of different evaluation approaches. Fibre straightness, fibre volume fraction, fibre orientation and fibre end accumulations are investigated in detail. Local strains are determined with digital volume correlation (DVC) and related to the true stress along the measured specimen length. The investigations showed that the test specimens do not necessarily break at the position of the smallest cross-section under uniaxial loading conditions. The failure behaviour of LFTs is strongly influenced by the local microstructure and thus the combination of various microstructural factors such as fibre bundles, fibre ends, local fibre volume fraction and orientation. [Display omitted] • Suggestion of a measurement workflow for in situ investigations of LFTs by CT. • Comparison of different fibre characterization approaches for LFTs. • Qualitative and quantitative analysis of factors triggering failure. • Local stress and strain analysis based on CT data and DVC. • Strength of LFTs strongly depend on the local microstructure. [ABSTRACT FROM AUTHOR]

For decades, composites have been mainly made up of petroleum-based plastics. But the priority on making our technology more sustainable has made research into bio-based materials so extensive, they are becoming viable alternatives. Natural fibers like flax can already challenge glass fiber in some applications. And the latest research is turning bio-based cellulose polymer into a matrix that can rival polypropylene. Could this be the game-changer the eco-purists have been hoping for? [ABSTRACT FROM AUTHOR]

Asource of waste post-industrial continuous glass fiber reinforced polypropylene (PP/GF) tape was investigated by means of thermo-mechanical recycling into long fiber thermoplastic (LFT) composite material. The glass fiber content was initially 70 wt.% in the tape and diluted to 40 wt.% in the LFT. Different approaches were investigated to reduce the size of the material into processable dimensions while retaining the quality of the fibers. The resulting flakes were melt-processed and the mechanical behavior determined. Competitive mechanical performance was obtained in terms of stiffness, strength and toughness compared to commercial reference materials made of long fibers. [ABSTRACT FROM AUTHOR]

The deposition of steel powders on glass fiber reinforced polymer (GFRP) with the Cold Spray technique is investigated. Metallization of composite materials is still challenging when high-strength and dense powders, such as steel, are used due to excessive erosion of the polymer or disruption of the fibers during the deposition. To overcome these issues, low-pressure cold spray equipment has been used for the experimental campaign shown in this paper. Different coatings were obtained by using nitrogen as the carrier gas and different sets of pressure and standoff distance. Optimization of the process parameters, including the stratification of the laminate, has been carried out. Results of an initial study of the feasibility of the process and the influence of the different chosen spray conditions are exposed. In particular, the bonding mechanisms of steel powders and their morphology are discussed. [ABSTRACT FROM AUTHOR]