Glass-Fibers Research Papers - Academia.edu (original) (raw)

2025, Civil and Environmental Engineering

In this paper, a new masonry construction is proposed based on honey beehive cell internal geometry as a unique structure and hydrostatic pressure principle. The considered experimental program involved suggestion, manufacturing, testing and analysis of masonry specimens of honey beehive units’ arrangement as well as corresponding specimens of custom arrangement, two classes of cementations bonding mortars are used. Plan strain concept and Saint Venant’s principle are adopted to model and assign proper boundary conditions of testing specimens. The significant improvement of masonry construction bearing capacity is confirmed by the obtained results and could be related to the presence of internal or self-confining pressure, which is produced due to the specific internal geometry of proposed honey beehive units’ arrangement of hexagonal construction units. The obtained results show that, the masonry specimens of proposed honey beehive arrangement Mode II exhibited higher bearing capac...

2025

Copyright © 2006, American Concrete Institute. All rights reserved including rights of reproduction and use in any form or by any means, including the making of copies by any photo process, or by electronic or mechanical device, printed, written, or oral, or recording for sound or visual reproduction or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors.

2025, Composites Part B: Engineering

Fiber-reinforced composite panels used in aerospace applications often experience low-velocity impacts (LVI) during service and maintenance by objects of various shapes, sizes, and masses, which can significantly reduce the panel's residual compressive strength. This study provides a detailed numerical and experimental analysis of LVI and compression after impact (CAI) failure mechanisms of laminates impacted by different impactor sizes and masses, along with damage accumulation during multiple impacts, and presents an effective approach for modeling progressive damage in composite laminates. The experiments were conducted using three hemispherical impactors with diameters of 6.35 mm (sharp), 25.4 mm (standard), and 96 mm (blunt), at impact energy levels of 30 J and 75 J, corresponding to barely and clearly visible impact damage (BVID and CVID). Quasi-isotropic IM7/977-3 composite specimens, sized 254 mm × 304.8 mm, were used to better represent large composite panels and study a wider range of impact scenarios. A finite element modeling methodology was developed based on the integrated enhanced LaRC05 failure criteria and the cohesive zone modeling technique to predict various composite failure modes, such as fiber breakage, pull-out, kinking, crushing, and splitting, as well as matrix cracking and delamination. The LaRC05 fiber tensile failure criterion was revised based on experimental data, improving the accuracy of the model at higher impact energies. At the same energy level, the sharp impactor caused more concentrated and severe damage, leading to lower CAI strength. The blunt impactor caused less surface damage but similar internal delamination and CAI strength compared to the standard impactor.

2025, Construction and Building Materials

MWCNTs well-dispersed in resin prior to fabrication produce a UV-resistant GFRP. 0.5-1.0 wt% carboxylic functionalized MWCNTs protect GFRP against UV degradation. UV-resistant GFRP eliminates the need to apply UV protection paint.

2025, Autex Research Journal

Plastic optical fibres (POF) are often used in telecommunication, consumer electronics and automotive applications. Measuring and control devices used for POF are already standardised procedures. To meet the requirements of the IEEE 1394 standard for data transfer rates up to 800Mbps requires increasingly improved performance of POF. POFs which offer high bandwidth, total electromagnetic immunity and simple handling are considered as an alternative to noisy copper cables (cat 5) and high performance glass optic fibres for of a data highway. The market requires a simple and inexpensive alternative that would not be a technical overkill. The target of the study carried out in the

2025

DISCLAIMER The use of company or product name(s) is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry. September 2002. This edition supersedes any previously released draft or final profile. Toxicological profiles are revised and republished as necessary. For information regarding the update status of previously released profiles, contact ATSDR at: Toxicological Profiles are a unique compilation of toxicological information on a given hazardous substance. Each profile reflects a comprehensive and extensive evaluation, summary, and interpretation of available toxicologic and epidemiologic information on a substance. Health care providers treating patients potentially exposed to hazardous substances will find the following information helpful for fast answers to often-asked questions. Chapter 1: Public Health Statement: The Public Health Statement can be a useful tool for educating patients about possible exposure to a hazar...

2025, International Journal of Engineering Science (IJES)

Computer simulation offers the potential for improved understanding of the local and global mechanisms that determine the response of structures to severe loading. The research presented here focuses on development of a finite element model using ABAQUS software to be used in investigating the behaviour of precast concrete exterior beam-column connection and compared with conventional beam column connection. Laboratory investigation of reinforced and precast concrete beam-column connections indicates that component failure may result from inelastic material behaviour of plain concrete and reinforcing steel. Thus, model development includes investigating and characterizing the behaviours of these materials. Concrete damaged plasticity model is used to represent the response of plain concrete. Comparison of computed and observed behaviour of reinforced and precast concrete elements indicates that the model used represents the local response mechanisms that determine global behaviour correctly. The current research helps one to have an improved understanding of finite element modelling of precast reinforced concrete and conventional concrete subassemblies in ABAQUS software. Comparison of load displacement diagram of RCC and precast beam column joint subjected to monotonic loading by using ABAQUS software and nonlinear modeling of connections are represented. It is observe that the precast beam column connection is giving good load displacement behaviour than conventional connection.

2025, Journal For Basic Sciences

The fabricated nanocomposites using epoxy/polyester and epoxy/vinylester systems 1 & 2 combined with various weight ratios of nanoiron particles (1, 2, 3, 5, and 7 wt.%). Chemical reduction produced the nanoiron particles, which were then manually laid up with ultrasonication and mechanical stirring to ensure homogeneity. Mechanical properties including hardness, tensile strength, flexural strength, impact strength, and compression strength were measured. Nanoiron particle incorporation improved mechanical properties due to uniform chemical bonding and diffusion within the polyester matrix, resulting in enhanced magnetic hardness. ANOVA analysis compared machine-generated mechanical property values with system-produced ANOVA values for specimens across varying nanoiron particle weights.

2025, Academia Materials Science

Sandwich panels provide a platform for integrating bio-based materials without compromising mechanical performance. This study investigates the physical and bending properties of sandwich panels composed of glass fibre composite skins and a bio-based castor oil foam core. Synthetic (epoxy) and bio-based (castor oil polyurethane) polymer systems are assessed as the matrix phase and as the adhesive between the skin and core, resulting in three experimental conditions. The panels constructed entirely from epoxy polymer achieved a flexural modulus of 1.61 GPa, while those made with castor oil polymer achieved 1.32 GPa. An intermediate panel, combining epoxy composite skins with castor oil adhesive, reached a flexural modulus of 1.41 GPa. Additionally, the absolute and specific properties, including the yield stress, flexural strength, and ultimate mean strain, were calculated and analysed. The fracture behaviour was characterised by localised core crushing with no skin delamination or fracture, indicating strong adhesion between the skin and core. These findings highlight the potential of sustainable sandwich structures as viable alternatives to traditional epoxy-based panels.

2025, Unknow

OMBNo 0704-0188 Esp Dare Jun30, 1986 la, REPORT SECURITY CLASSIFICATION lb RESTRICTIVE MARKINGS UNCLASSIFIED None 2a SECURITY CLASSIFICATION AUTHORITY 3. DISTRIBUTION/AVAILABIUTY OF REPORT N/A Approved for public release; 2b. DECLASSIFICATION /DOWNGRADING SCHEDULE N/A distribution is unlimited. 4 PERFORMING ORGANIZATION REP'--RT NUMBER(S) 5. MON.ITORING ORGANIZATION REPORT NUMBER(S) TR-RD-RE-90-3 64. NAME OF PERFORMING ORGANIZATION 6b. OFFICE SYMROL 7a. NAME OF MONITORING ORGANIZATION Research Directorate i applicabe) Res., Dev.. and Eng. Center AMSMI-RD-R _ 6c. ADDRESS (0ty, State, and ZIP Code) 7b. ADDRESS(Cityo Stare, and ZIP Code) Commander, U. S. Army Missile Command ATITN: AMSMI-RD-RE-OP Redstone Arsenal, AL 35898-5248 va NAME OF FUNDING ISPONSORING 8b. OFFICE SYMBOL 9 PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER CAANIZATION Of applicable) 8C. ADDRESS (City, State, and ZDP Code) 10. SOURCE OF FUNDING NUMBERS PROGRAM PROJECT TASK WORK UNIT ELEMENT NO. NO NO. ACCESSION NO 11, TITLE (include Secunty Clasification) Diffraction Pattern Analysis as an Optical Inspection Technique 12. PERSONAL AUTHOR(S) Gregory, Don A. and Alexander, Helga A. 13&. TYPE OF REPORT 113tU. TIME COVERED A.t "ATE Otr F EPORT (Year, Month, Day) I'5 " PAGE COUNT Final I FR0MJlaILe_ TO. Oct 89 IAugust 1991 2 27 16. SUPPLEMENTARY NOTATION 17. COSATI CODES 15. SUBJECT TERMS (Continue on revere if necessary and identify by block number) FIELD GROUP SUB-GROUP I IDiffraction, Optical inspection 19. ABSTRACT (Continue on reverse if necessary and identify by block number) A few examples are presented which illustrate the usefulness of optical inspection techniques. Diffraction patterns produced by defects are often distinctive and can be used to examine objects nonde'tructively. It was also found that if the defect is minor and occupies only a small fraction of the illumination area, the defect diffraction pattern cannot be distinguished from the bright background.

2025

: The U.S. Army makes worldwide use of high-performance ballistic-resistant fiberglass composite panels for force protection and other applications. This widespread use creates a need for an improved panel material that offers better bullet resistance at a lighter weight while still meeting existing ballistic resistance standards. The team s work to solve the Army s need included conceiving, developing, and validating a new nanocomposite material that is made of epoxy resin blended with functionalized carbon nanotubes (CNTs) that exhibits highly improved flexural strength and electrical conductivity for improving ballistic resistance in lighter weight glass fiber reinforced polymer (GFRP) ballistic panels. In addition, the team s work tested various options for adding self-healing, CNT reinforcement, EMI shielding, and self-decontaminating properties for GFRP panels. Results of separate studies included in this report are: loading panels with CNTs by using different mass fractions a...

2024, Composites Part B-engineering

Fiber reinforced Polymer (FRP) composites are currently employed in the civil engineering industry as externally bonded reinforcement (EBR) of existing reinforced concrete (RC) and masonry structures and as internal re-inforcement of concrete elements as an alternative to steel reinforcing bars. Carbon FRP (CFRP) composites are mainly used for EBR applications whereas glass FRP (GFRP) bars are employed as internal reinforcement of concrete elements. This paper sheds light into the effect of different aggressive environments on the tensile behavior of reinforcing GFRP bars. 356 results of tensile tests of GFRP bars subjected to hot dry and humid air, different alkali environments, salt solutions with various concentrations, and plain and distillated water were collected from the literature. According to the "design by testing" procedure provided by EN 1990, a statistical analysis of the results was carried out to calibrate environmental reduction factors able to provide reliable estimations of the long-term behavior of GFRP bars subjected to different exposure conditions. For a given aggressive environment, a clear and unique degradation trend could not be identified, which points out the need of a standard testing procedure able to provide reliable and repeatable results.

2024

A common bad characteristic expansive soil which is randomly located in hot terrorism areas located in the middle of Iraq. This is required to improve the soil , then implement a flexible roads for reaching to those areas quickly. A copper coated micro steel fiber (CCMSF) is chosen to stabilize the sub grade soil of flexible roads. An experimental study focused on the physical properties of the resulting stabilized soil has been achieved. Various percentages fiber/soil of (1, 2, 3, 4 &5%) are tested for CBR, Indirect Tensile Strength & Linear Shrinkage percent to investigate the improvements and due to the suggested addition and the physical manipulations obtained by comparing with a control samples (zero fiber content). It is found that a 3% fiber/soil offers the best fit with engineering specification and economic feasibility coast. Accordingly, 3% of CCMSF increases the CBR and Indirect Tensile Strength values with 114% and 122% respectively, whereas Linear Shrinkage value reduces with 70%. However, the increment in CBR reduces the design thickness of the flexible pavement constructed above such stabilized sub grade soil with 39% comparing with non-stabilization soil of similar circumstances. Thus in turn leads to shorten the implementation time of flexible pavement by the same percentage and saving the implementation road cost by about 24%.

2024

Kenaf reinforced polyethylene composites for ballistic protection was produced in this work. The samples of alkaline treated and silane-coupled non-woven matted kenaf fibers were cut to the required dimensions and oriented vertically and horizontally in combinations with a virgin high density polyethylene (VHDPE). The composite panels were produced using Box-Behnken 3-variables settings. The following factors settings were used (molding temperature: 160C to 200C; molding time: 60minutes to 80minutes; fiber volume fraction: 10% to 30%) based on dry mass in a two-piece mild steel compression molding set. The pressure for heating and cooling was controlled at 12MPa. The responses as tensile and flexural values were determined and optimized. The composite sample of VHDPE ballistic test were blended based on the optimum settings of temperature: 200C; molding time: 80minutes and fiber volume fraction:30%) and tested with Jojeff Magnum riffle gun. The mechanical and ballistic properties of...

2024

AB.S_IXA.CE A new type of braided fiber seal has been developed for high temperature engine applications. Development work performed in this study includes seal design, fabrication, leakage flow testing, and flow resistance modeling. This new type of seal utilizes the high flow resistance of tightly packed fibers and the conformability of textile structures. The seal contains a core part with aligned fibers, and a sheath with braided fiber layers. Seal samples are made by using the conventional braiding process. Leakage flow measurements are then performed. Mass flow rate versus the simulated engine pressure and preload pressure is recorded. The flow resistance of the seal is analyzed using the Ergun equation for flow through porous media, including both laminar and turbulent effects. The two constants in the Ergun equation are evaluated for the seal structures. Leakage flow of the seal under the test condition is found to be in the transition flow region. The analysis is used to predict the leakage flow performance of the seal with the determined design parameters.

2024, Iconic Research And Engineering Journals

2024, Fibers

Understanding the strength degradation of glass and carbon fibers due to exposure to liquids over time is important for structural applications. A model has been developed for glass fibers that links the strength reduction in water to the increase of the Griffith flaw size of the fibers. The speed of the increase is determined by regular chemical dissolution kinetics of glass in water. Crack growth and strength reduction can be predicted for several water temperatures and pH, based on the corresponding dissolution constants. Agreement with experimental results for the case of water at 60 • C with a pH of 5.8 is reasonably good. Carbon fibers in water and toluene and glass fibers in toluene do not chemically react with the liquid. Subsequently no strength degradation is expected and will be confirmed experimentally. All fiber strength measurements are carried out on bundles. The glass fibers are R-glass.

2024, Fibers

Understanding the strength degradation of glass and carbon fibers due to exposure to liquids over time is important for structural applications. A model has been developed for glass fibers that links the strength reduction in water to the increase of the Griffith flaw size of the fibers. The speed of the increase is determined by regular chemical dissolution kinetics of glass in water. Crack growth and strength reduction can be predicted for several water temperatures and pH, based on the corresponding dissolution constants. Agreement with experimental results for the case of water at 60 °C with a pH of 5.8 is reasonably good. Carbon fibers in water and toluene and glass fibers in toluene do not chemically react with the liquid. Subsequently no strength degradation is expected and will be confirmed experimentally. All fiber strength measurements are carried out on bundles. The glass fibers are R-glass.

2024, journal of metallurgical and materials engineering

In this research, aluminum matrix reinforced with continuous carbon and glass fibres composite were produced using A356 aluminum alloy as the matrix, and T300 carbon fiber and E-glass as the reinforcement during the squeeze casting process. Carbon fibers were first coated with a layer of nickel-phosphorus using the electroless method. Then, aluminum alloy 356 pipe and composite pipes with 30 weight percent of carbon fibers and 30,40,50 and 60 weight percent of glass fibers were cast at 75 MPa and 500 °C. After casting, the microstructure, and mechanical properties of composite samples were investigated. Nickel-phosphorus coating on carbon fibers has a significant effect on the wettability of carbon fibers with aluminum melt and thus the penetration of aluminum melt into carbon fibers. The hardness of composite pipes reached approximately 2 times that of alloy pipe and the density decreased to 9.5% with increasing weight percent of fibers. The highest bending strength was obtained at 340.82 MPa, which is related to the reinforced composite pipe with40 weight percent of glass fibers. Tensile strength was measured by the nol ring test, in which a composite tube with 30 weight percent of carbon fiber had the highest tensile strength with a 76% increase over the alloy pipe. The predominant mechanism in the failure of carbon fiber-reinforced composite pipe was fiber pull-out and in the failure of glass-fiber-reinforced composite pipes, the fibers were cut.

2024, CRC Press eBooks

The development of permanent lunar bases is constrained by performance of construction materials and availability of in-situ resources. Concrete seems a suitable construction material for the lunar environment, but water, one of its major components, is an extremely scarce resource on the Moon. This study explores an alternative to hydraulic concrete by replacing the binding mix of concrete (cement and water) with sulfur. Sulfur is a volatile element on the lunar surface that can be extracted from lunar soils by heating. Sulfur concrete mixes were prepared to investigate the effect of extreme environmental conditions on the properties of sulfur concrete. A hypervelocity impact test was conducted, having as its target a 5-cm cubic sample of sulfur concrete. This item consisted of JSC-1 lunar regolith simulant (65%) and sulfur (35%). The sample was placed in the MSFC Impact Test Facility's Micro Light Gas Gun' target chamber, and was struck by a 1-mm diameter (~1.4e-03 g) aluminum projectile at 5.85 km/s. In addition, HZTERN code, provided by NASA was used to study the effectiveness of sulfur concrete when subjected to space radiation.

2024, International Journal of Scientific & Technology Research

Steel fibers are added to concrete due to its ability to improve the tensile strength and control propagation of cracks in reinforced concrete members. Steel fiber reinforced concrete is made of cement, fine, water and coarse aggregate in addition to steel fibers. In this experimental work, flexural cracking behavior of reinforced concrete beams contains different percentage of hooked-end steel fibers with length of 50 mm and equivalent diameter of 0.5 mm was studied. The beams were tested under third-point loading test at 28 days. First cracking load, maximum crack width, cracks number, and load-deflection relations were investigated to evaluate the flexural cracking behavior of concrete beams with 34 MPa target mean strength. Workability, wet density, compressive and splitting tensile strength were also investigated. The results showed that the flexural crack width is significantly reduced with the addition of steel fibers. Fiber contents of 1.0% resulted in 81% reduction in maxim...

2024, Polymers for Advanced Technologies

The natural fibers such as jute, coir, hemp, sisal etc. are randomly used as reinforcements for composite materials because of its various advantages such as low cost, low densities, low energy consumption over conventional fibers. In addition, they are renewable as well as biodegradable, and indeed wide varieties of fibers are locally available. In this study, glass–jute fiber reinforced polymer composite is fabricated, and the mechanical properties such as tensile, flexural and impact behavior are investigated. The materials selected for the studies were jute fiber and glass fiber as the reinforcement and epoxy resin as the matrix. The hand lay‐out technique was used to fabricate these composites. Fractured surface were comprehensively examined in scanning electron microscope (SEM) to determine the microscopic fracture mode. A numerical procedure based on the finite element method was then applied to evaluate the overall behavior of this composite using the experimentally applied ...

2024, Construction and Building Materials

h i g h l i g h t s The behavior of spliced GFRP and steel bars in normal concrete (NC) and self-consolidated concrete (SCC) are presented. Failure modes of spliced GFRP and steel bars in NC and SCC are presented and discussed. The effect of splice length and section height along with the type of concrete on the bond capacity were discussed. The accuracy of the current design provisions is assessed based on the test results.

2024

Aluminium alloys lack resistance to wear when subjected to erosive conditions. A solution has been the development of ceramic coatings on the surface of the alloy to sustain wear. This work reports the study conducted to evaluate the resistance to abrasion by sand of plates of an aluminium alloy processed to develop ceramic coatings of different thicknesses used in the manufacture of silica sand cores. The samples were subjected to erosion by either silica sand or with the mixture of sand and binder that were blown on the surface of the coated plates to reproduce the conditions to which core moulds are subjected to during sand-core manufacturing. The experimental design contemplated changing the angle of impingement of the plate as well as the pressure and velocity of the sand stream. The results of the tests show the feasibility of replacing traditional tool steel moulds by aluminium coated ones.

2024, VEGETABLE POLYURETHANE RESIN BIOCOMPOSITES WITH TITICA VINE FIBER TEXTILE REINFORCEMENT: A REVIEW (Atena Editora)

Given the growing need for alternative products to synthetic fibers to obtain more sustainable and environmentally friendly products, natural fibers are proving increasingly promising when applied as reinforcement in polymer composites. Taking into account the pollution generated by the exploration of oil and derivatives and the increasingly present threat of their depletion, the academic and industrial sectors are progressively investing in alternative solutions to these non-renewable sources like the use of polymers based on plant resources, such as castor oil-based polyurethane resin. Therefore, this study aimed to analyze, based on a brief literature review, the application of plant resources in composites, both for reinforcement and for the polymeric matrix . This process is proving an increasingly present and urgent trend in the most diverse industrial sectors, adding significant gains to both the environment and society, based on the review study of biocomposites reinforced with titica vine fiber and polyurethane matrix derived from a plant resource.

2024, 16Th International Conference on Composite Structures

This study aims to investigate the influence of stitch density and stitch thread thickness on compression after impact (CAI) strength of stitched composites. Unstitched laminated composites and specimens stitched with varying stitch density and stitch thread thickness are subjected to impact damage and then compressive loading. It is shown that stitched composites have higher CAI strength than unstitched counterpart due to smaller impact-induced delamination area, where local buckling occurs during compressive failure. However, it is revealed that the effectiveness of stitching in suppressing delamination growth and inhibiting sublaminate buckling under compressive loading is intimately related to stitch density. It is also found out that stitch thread thickness has little influence on CAI strength at low impact energy level, but has considerable effect at high impact energy level.

2024

In recent years, great attention has been devoted towards the use of natural fibers as reinforcement for polymer composites due to the fact that this material possesses characteristics that are comparable to conventional materials. Among various natural fibers, bamboo has been widely used for many such applications due to its availability and low cost. In the present research work, the mechanical behavior of short bamboo fiber reinforced epoxy composites filled with alumina particulate has been evaluated. Attempts have been made not only to explore the potential utilization of bamboo fiber in polymer matrix composites but also to study the effect of various parameters on the performance of these composites. Finally, the scanning electron microscope (SEM) of fractured surfaces has been done to study their surface morphology.

2024, Journal of Non-Crystalline Solids

In the development of high bit-rate capacity in telecom systems, fiber technology and/or integrated glass waveguides provide a means to implement low cost active optical devices with low insertion losses and fiber compatibility. Presently glassbased devices are limited in efficiency and it is of the utmost importance to increase the non linear optical response. In this context the present investigation compares the induced second-order optical nonlinearity generated after electro-thermal poling process in a series of borophosphate glasses of molar compositions 0.3[(0.9x) Ca(PO 3) 2-x Zn(PO 3) 2-0.1 CaB 4 O 7 ]-0.3 Nb 2 O 5 (x = 0-0.4). The mechanisms involved are tentatively explored.

2024, Procedia Engineering

International Symposium on "Novel structural skins-Improving sustainability and efficiency through new structural textile materials and designs" A study on the durability properties of textile membranes for architectural purposes

2024, AIP Conference Proceedings

Extensive use of composite materials for different structures imposes a thorough study of this type of materials. Of interest in structural design, like tailoring the composite wing box beam to increase performances while preserving proper airworthiness, are the failure mechanisms and delamination of common composite materials. Since the fracture testing of fiber reinforced composites is still an open research domain, the present paper investigates the delamination of unidirectional carbon-fiber reinforced composite material. The opening-mode interlaminar fracture toughness is studied using the simple beam theory and the corrected beam theory. Quasi static tests are made on double cantilever beam according to the standards. In order to measure the crack growth, a high resolution camera was used. The test data and the video recorder measurements have proved that the corrected beam theory is more useful for energy release rate calculation.

2024, Journal of Textiles and Polymers

In the first part of this series, a straight-line geometrical model was generated for Queen's Cord warpknitted fabrics as reinforcement of the composite. In this part, the Rule of Mixture (ROM) was modified to calculate the elastic modulus of composites reinforced with Queen's Cord fabrics using the straight-line model. For this purpose, the geometrical model was divided into different segments, and their angle with the direction of applied force was obtained. Considering the alignment of each segment, the effective length of different segments of the unit-cell of fabrics was calculated. Using the effective length, an orientation coefficient was defined for tensile modulus of fibers in ROM. In order to evaluate the modified ROM, nine types of composites were fabricated using produced Queen's Cord fabrics. The results showed that modified ROM is closer to experiments than previous modifications.

2024, Material Design & Processing Communications

The nonlinear, anisotropic, and multiscale mechanical behavior of knitted textiles is investigated experimentally in this article. The approach is motivated by recent computational work by the authors that revealed, for the first time to their best knowledge, local-global mechanical behavior effects related to the hierarchical, three-dimensional structure of this type of materials. The investigation is carried out on single jersey knitted textile specimens. Mechanical testing consisting of tensile loading along the two principal directions was coupled with a noncontact, optical metrology method capable of providing deformation measurements. The effect of globally applied loading on yarn-to-yarn interactions was explored using measured data. The results validate the previously obtained computational findings that include the anisotropic behavior between course and wale directions, the pronounced out-of-plane motion observed when in-plane loading is applied, as well as the characteristic nonlinear mechanical behavior of knitted textiles. These effects were linked to direct observations of the loop structure that demonstrated the coupling between local kinematics and kinetics with global mechanical behavior.

2024, Optics Express

All solid-state PbS quantum dot (QD)-doped glass precursor fibers avoiding crystallization during fiber-drawing process are successfully fabricated by melt-in-tube technique. By subsequent heat treatment schedule, controllable crystallization of PbS QDs can be obtained in the glass precursor fibers, contributing to broad near-infrared emissions from PbS QD-doped glass fibers. Nevertheless, we find that element-migration and volatilization of sulfur simultaneously happen during the whole fiber-drawing process, because of the huge difference between the melting temperature of core glass and the fiberdrawing temperature. Element-migration pathways along the fiber length were revealed. Such PbS QD-doped glass fiber with broadband emissions will be a potential application as gain medium of broadband fiber amplifiers and fiber lasers.

2024, Journal of Non-Crystalline Solids

The development of a new generation of chalcogenide infrared glass fibers allows making an IR sensor that permits recording the fingerprints of biomolecules in the mid infrared (MIR) range. The measurements are based on the general concept of evanescent wave spectroscopy. To improve the detection, the diameter of the fiber is locally reduced. To test this optical sensor, we measured metabolic anomalies in relation with hepatic pathologies. Mouse liver tissues have been used and MIR spectra have been recorded by a mere contact between tissues and the surface of the fiber. Spectral differences reflect metabolic alterations, these can be identified and assigned. Furthermore, histologic studies confirm these results.

2024, International Journal of Engineering Science (IJES)

2024

Busin e s s a n d Econom ic s J o urn al

2024

The objective of the investigation is to explore a new approach for high sensitivity structural health monitoring of continuous glass fiber reinforced polymer composites (GFRPs). Conductive nanofillers were used for tailoring the anisotropic conductivity of GFRP. Carbon nanotubes and carbon blacks were anisotropically networked using dielectrophoretic manipulation during processing. Smaller, low-aspect-ratio nanofillers (carbon black) in low concentrations were superior to high-aspect-ratio nanofillers (nanotubes) for electrical tailoring purposes. Networking of carbon black nanoparticles through the thickness increased the detectability of delamination.

2024, IAEME PUBLICATION

2024

The present research aimed to investigate the effect of stitching angle and stacking sequence of stitched layers on high velocity impact behavior of composites reinforced by glass woven fabrics. To study the effect of stitching angle on ballistic impact behavior, six different angles of (0), (90), (45), (0 ,90), (AE45) and (0 ,90 ,AE45) were chosen as stitching angles. These stitching angles were applied on eight layers of glass woven fabric. To study the effect of stacking sequence of stitched layers, a different number of layers were stitched together with the angle of 0. Unstitched and stitched composites were exposed to high velocity impact with 180 m/s using a spherical projectile. The residual velocity of projectile and dimensions of damage area on the composites' front and back sides were measured. It was found that the sample with the 45 stitching angle had the best behavior against ballistic impact and its energy absorption was significantly higher than the other samples. Stitching also reduces damage area in front and back sides of the composites and inhibits delamination.

2024, Procedia structural integrity

Ceramics matrix composites are rather expensive due to the demanding processing as well as costly raw materials. Modification of the surface of the fibre is the most common but expensive technique to maximise toughness of CMCs. The prospective method can be a modification of a matrix as was demonstrated for the SiOC matrix reinforced by basalt fibres recently. The partially pyrolysed SiOC matrix based composites at 650°C were used for this study. All production parameters remain the same only reinforcing fibres were different. This work aims at the fibre chemical composition effect on the mechanical properties of composites. The strong effect of the fibres used is observed on the flexural strength values where basalt fibres reaching the level of 800 MPa. The composites reinforced by carbon and R Glass reached 200 MPa and E Glass only 125 MPa. The fracture toughness values correspond well with the flexural strength results which are in a good agreement with the expectations when the defect size is on the comparable level. Two silicate glass fibres with similar chemical composition as basalt fibres, differing mainly in the presence of iron oxides what indicates that iron oxide is responsible for an optimal fibre-matrix bonding in case of basalt fibre reinforced composite.

2024, Composites Part B-engineering

Composites utilising long fibres as reinforcement are the most effective from the point of view of the toughening effect. A brittle matrix reinforced by brittle fibres was investigated in this work. Polysiloxane resin was used as matrix precursor in the studied composite, while continuous basalt fibres served as reinforcement. An optimised pyrolysis process conducted at 650°C under nitrogen atmosphere turned the polymeric precursor into the so-called hybrid matrix consisting of nano-domains of pyrolytic SiOC glass and of non-transformed polysiloxane polymer. The pyrolysis temperature of 650°C was found to be optimal, resulting in the fracture toughness attacking the level of 20 MPa.m 1/2 and the strength the value of 1 GPa. The main aim of this paper is to investigate microstructural changes occurring during long-term (1000 hours = 41.7 days) exposition to an oxidative air atmosphere at temperatures from 250°C to 600°C and to describe the effect on the mechanical properties of the studied hybrid-matrix composite. The increasing exposition temperature leads to a significant embrittlement of the composite, while the elastic properties (modulus) remain unchanged. Chemical or microstructural changes in the basalt fibres were not detected after the long-term exposition to the tested high temperatures. Nevertheless, fibre embrittlement can be estimated from the tests. Both matrix and fibre-matrix interface were found to suffer from the applied exposition. Distinct changes in chemical composition as well as in microstructure were observed for the matrix. Hence, the observed embrittlement of the composite can be ascribed partially to the changes in the hybrid matrix and the fibre-matrix interface, and partially to fibre embrittlement.

2024, Composites Part B: Engineering

2024, Zenodo (CERN European Organization for Nuclear Research)

While Glass Fibre-Reinforced Polymer (GFRP) decks offer a competitive solution for bridge construction and renovation, their application is constrained by the absence of feasible, fatigueresistant connection technologies. Current methods, including bolted, bonded, and cementitious groutbased connections, exhibit various limitations. The emerging injected Steel Reinforced Resin (iSRR) connector technology promises enhanced performance. However, its behaviour within a realistic bridge deck scenario, particularly under the influence of web direction, remains under-explored. This paper scrutinises these connectors in a sandwich web core panel setup, subjected to fully reversed loading cycles and post-fatigue static tests, with the aid of Finite Element modelling.

2024

Fiber reinforced polymer composites has been used in a variety of application because of their many advantages such as relatively low cost of production, easy to fabricate and superior strength compare to neat polymer resins. Reinforcement in polymer is either synthetic or natural. Synthetic fiber such as glass, carbon etc. has high specific strength but their fields of application are limited due to higher cost of production. Recently there is an increase interest in natural fiber based composites due to their many advantages. In this connection an investigation has been carried out to make better utilization of coconut coir fiber for making value added products. The objective of the present research work is to study the physical and mechanical behaviour of coir/glass fiber reinforced epoxy based hybrid composites. The effect of fiber loading and length on mechanical properties like tensile strength, flexural strength, hardness of composites is studied. Also, the surface morphology of fractured surfaces after tensile testing is examined using scanning electron microscopy (SEM).

2024, Business and Economics Journal

The kenaf plant is eco-friendly, renewable, low in cost and not meant to be a food source, owing to its potential commercial value in Malaysia, the government has allocated millions of ringgit for research to develop a viable kenafbased industry. This study is an attempt to assess the financial and technical performance of kenaf cultivation to produce fiber usage in automotive components. The financial data were collected through interviews with kenaf growers and from group discussions as well as production data collected from CMPC (Kenaf Processing and Marketing Centre) Bachok-Kelantan. The financial data were analyzed using Microsoft Excel software while Eview8 was used to analyze the production data. Three scenarios of kenaf production per hectare were assumed which were 15, 12 and 10 ton. According to the data analysis; the results revealed when kenaf production was 15 ton/ha, the farmer made a maximum profit of 37% from the subsidy provided by the Lembaga Kenaf Dan Tembakau Negara (LKTN) or National Kenaf and Tobacco Board, which was more than double the profit margin without subsidy. The financial analysis illustrated that all the three scenarios were viable when using the Benefit Cost Ratio (BCR) as an indicator. However, the production of 15 ton per hectare was the best of the three scenarios due to the five-year payback period, which was equal to half the period run on the model of the financial analysis. Additionally, the analysis of the production input (labor and chemicals) showed a significant effect on kenaf production as indicated in the analysis of Ordinary Least Square (OLS). Business and Economics Journal B us ines s a n d E cono m ic s Jo urna l

2024

An automatic flat knitting machine MATSUYA-M100 with 14 gauge was used for fabric knitting.