Hybrid Fiber Research Articles

Mechanical properties of steel fiber RPC, basalt fiber RPC, and hybrid fiber RPC: A review of research progress

AbstractBased on an analysis of the literature on fiber‐reinforced concrete (FRC), especially the development and formation of various types of FRC combined with reactive powder concrete (RPC) in recent years, this paper systematically expounds the research progress, particularly the mechanical properties, of steel fiber RPC, basalt fiber RPC and hybrid fiber RPC. This paper concludes the improvement in the mechanical properties of RPC under common curing methods, elaborates on the influence of steel fiber on the compressive, tensile, and flexural strength of RPC, and outlines the principle of fiber enhancing the mechanical properties of RPC. Additionally, it discusses the research progress in basalt FRC, and further examines the impact of basalt fiber on the mechanical properties of RPC. Referring to the research on single fiber reinforced RPC, the mechanical properties of hybrid fiber RPC are analyzed and summarized; based on the characteristics of steel fiber and basalt fiber, research on steel‐basalt hybrid fiber RPC is proposed.

Effect of hybridization and composite architecture symmetry in the bonded joint performance of jute/carbon fibre-reinforced composites

This study investigates the effect of hybridization and composite architecture symmetry in the bonded joint performance of jute/carbon fibre-reinforced composites. Jute and carbon fibre bidirectional fabrics were used as reinforcement fibres for interlaminar hybrid epoxy composite adherends. The effect of the number of carbon fibre layers (1 and 2) as well as layup symmetry on the mechanical performance of the bonded joints was studied by testing single lap joints (SLJs) bonded with two adhesive types (a structural ductile bi-component epoxy adhesive and a brittle one). It was found that the hybridization of jute fibre reinforced composites with carbon fibres significantly improved the bonded joint performance for all tested specimens, when compared to the neat jute fibre reinforced composites (maximum of approx. 69 %). However, when compared to the neat carbon fibre (CFRP) adherend joints, the hybrid jute/carbon adherend joint configurations studied here achieved up to approximately 94 % (ductile adhesive system) and 97 % (brittle adhesive system) of maximum joint load efficiency of the CFRP synthetic joint. The effect of composite architecture symmetry was more pronounced for the brittle adhesive joints, whereas the failure loads of the ductile adhesive joints exhibited a plateau-like trend (ductile adhesives accommodate better the bending moments during SLJ loading, while brittle adhesives are more sensitive to adherend stiffness). A jute/carbon fibre hybrid composite bonded structure presents a potentially cost-effective and efficient alternative for reducing the structural carbon footprint, without a significant compromise in mechanical properties.

Discontinuous Deformation Monitoring of Smart Aerospace Structures Based on Hybrid Reconstruction Strategy and Fiber Bragg Grating.

A hybrid enhanced inverse finite element method (E-iFEM) is proposed for real-time intelligent sensing of discontinuous aerospace structures. The method can improve the flight performance of intelligent aircrafts by feeding back the structural shape information to the control system. Initially, the presented algorithm combines rigid kinematics with the classical iFEM to discretize the aerospace structures into elastic parts and rigid parts, which will effectively overcome structural complexity due to fluctuating bending stiffness and a special aerodynamic section. Subsequently, the rigid parts provide geometric constraints for the iFEM in the shape reconstruction method. Meanwhile, utilizing the Fiber Bragg grating (FBG) strain sensor to obtain real-time strain information ensures lightweight and anti-interference of the monitoring system. Next, the strain data and the geometric constraints are processed by the iFEM for monitoring the full-field elastic deformation of the aerospace structures. The whole procedure can be interpreted as a piecewise sensing technology. Overall, the effectiveness and reliability of the proposed method are validated by employing a comprehensive numerical simulation and experiment.

Free and Forced Vibration Analysis of Carbon/Glass Hybrid Composite Laminated Plates Under Arbitrary Boundary Conditions

This paper presents the theoretical investigations on the free and forced vibration behaviours of carbon/glass hybrid composite laminated plates with arbitrary boundary conditions. The unknown allowable displacement functions of the physical middle surface are expressed in terms of standard cosine Fourier series and sinusoidal auxiliary functions to ensure the continuity of the displacement functions and their derivatives at the structural boundaries. Arbitrary boundary conditions are achieved through the introduction of an artificial spring technique. The first shear deformation theory and Lagrange equations are utilized to derive the energy expression, and the eigenvalue equations associated with free and forced vibration are obtained by Rayleigh-Ritz variational operations. Subsequently, these equations are then solved to determine the natural frequency, mode of vibration, and the steady-state displacement response under forced excitation. The new results are compared with those from references and finite element methods to verify the convergence, accuracy and efficiency of the analytical method. The effects of hybrid ratios, stacking sequences, lamination schemes, fibre orientation, boundary conditions and excitation force on the free and forced vibration behaviours of the carbon/glass hybrid composite laminated plates are analyzed in detail.

Enhancement of Perlite Concrete Properties containing Sustainable Materials by Incorporation of Hybrid Fibers

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

Retrofitting of heat-damaged fiber-reinforced concrete cylinders using welded wire mesh configurations

Abstract Fire damage poses a significant risk to reinforced concrete structures throughout their lifespan. Fire exposure influences the stress-strain properties and durability of concrete, despite its non-flammability. Therefore, the strengthening approach is an economic option for lengthening their lifespan. This paper aims to conduct an experimental investigation into retrofitting heat-damaged fiber-reinforced concrete cylinders using welded wire mesh (WWM) configurations. Four concrete mixes were investigated. In total, 48 concrete cylinders were tested under axial compression until failure. The primary variables considered in the testing program consisted of (i) the influence of various fiber types (steel fiber (SF), polypropylene (PP), and hybrid fibers (SF+PP)); (ii) exposure temperature (26°C and 600°C); and (iii) WWM strengthening. Exposure to a temperature of 600°C led to a significant reduction in the compressive strength, ranging from 23.7% to 53.3%, while the inclusion of fibers has a substantial effect on the compressive strength of concrete, regardless of fiber type, with an increased ratio reaching up to 34.7%. The finding also clearly shows that the strengthening of heat-damaged specimens with WWM jacketing resulted in a 38.8%, 4.9%, and 9.4% increase in compressive strength for SF, PP, and SF+PPF specimens, respectively, compared to unheated control specimens. The suggested approaches to strengthening, which involve the use of WWM jacketing with two layers, successfully restored and surpassed the initial concrete compressive strength of the specimens that were damaged due to exposure to high temperatures.

Behavior of Reactive Powder Concrete reinforced with Hybrid Fibers containing Sustainable Materials

Behavior of Reactive Powder Concrete reinforced with Hybrid Fibers containing Sustainable Materials

Interface bonding characteristics of 3D printed ultra-high performance concrete after elevated temperatures

This study explored the influence of elevated-temperature exposure and interlayer time intervals on the interface bonding strength of hybrid-fibre 3D printed ultra-high-performance concrete (3DP-UHPC), and analysed the potential mechanisms driving these observed results. A relationship model for the bonding strength of hybrid fibre 3DP-UHPC in elevated-temperature environments was proposed. Results revealed that at 800 °C, localized damage occurred in 3DP-UHPC, but the addition of 0.5 % polypropylene fibres delayed the occurrence of spalling behaviour and enhanced its elevated-temperature resistance. Furthermore, as the time interval increased, the bonding strength of 3DP-UHPC gradually decreased, particularly at temperatures above 400 °C, where the melting and volatilization of polypropylene fibres negatively affected the bonding strength. The study suggested that polypropylene fibres inhibited spalling behaviour of 3DP-UHPC after elevated temperatures through moisture loss and thermal stability. However, they may also lead to interface weakening, resulting in a decrease in bonding strength. These findings provide important guidance for further development and design of 3DP-UHPC structures in elevated-temperature environments.

Experimental study on strength and carbonation performance of hybrid fibre lightweight aggregate concrete in precast structures

To improve the brittle failure characteristics and carbonation performance of lightweight aggregate concrete, basalt fibre, and polyacrylonitrile fibre were incorporated. The effects of the two fibres on the compression strength and carbonation depth were studied through compression tests and rapid carbonation tests. The effects of mineral admixture proportion were also studied. The results show that when the mass content of basalt fibre and polyacrylonitrile fibre is 2.8 kg/m3 and 0.9 kg/m3, respectively, the average increase of compression strength for different ages is approximately 40%, and the average decrease of carbonation depth for different ages is approximately 8%. Furthermore, when the mass content of mineral admixture is 30%, the higher proportion of slag contributed to the greater compression strength, but smaller carbonation depth. As supported by the experimental results, the improvements in strength and carbonation performance of lightweight aggregate concrete will make it more competitive in the application of precast buildings and long-span bridges.

Experimental Study of Structural Crack Monitoring for Ocean Platform Based on a Hybrid Fiber Sensing Technique

Experimental Study of Structural Crack Monitoring for Ocean Platform Based on a Hybrid Fiber Sensing Technique

Mechanical behaviour analysis for banana/coir natural fiber hybrid epoxy composites through experimental modelling

Mechanical behaviour analysis for banana/coir natural fiber hybrid epoxy composites through experimental modelling

Scratch resistance of glass‐basalt fiber reinforced epoxy hybrid composites: A comparative study

AbstractThis research explores the scratch resistance of polymer composites reinforced with hybrid glass and basalt fibers under repeated loadings. By examining the behavior across 1–10 repetitions using Rockwell and Vickers indenters, the study delves into the complex interplay between composite matrices and the fibers' configurations. Through Scanning Electron Microscope (SEM) imaging and 3D profilometry, it reveals how different fibers influence the composite's surface post‐scratch tests. Basalt fibers are found to offer superior scratch protection over glass fibers, although both types' of effectiveness declines with increased loading cycles, showing significant material loss and surface damage respectively. Composites with these fibers display enhanced resistance, especially when basalt fibers are optimally positioned on the surface. The study underscores the critical role of fiber‐matrix bonding in scratch resistance and the significant impact of mechanical stress. It was found that the scratch hardness values reduced with more repeats in the scratch tests utilizing Vickers and Rockwell indenters. The sample with the label G4B6G4 has the greatest hardness values, which is noteworthy. After 10 repeats, the scratch hardness values for this sample reduced to 225 N/mm2 and 75 N/mm2, respectively, from roughly 340 N/mm2 and 225 N/mm2 at both ends for a single repetition. In addition, ANOVA for penetration depth is dominated (66.01%) by the repetition factor. The most common kind is indenter (42.79%), with low p‐values. Despite material and indenter effects, groove area study confirms the significance of repetition (65.72%).Highlights Basalt fibers enhance scratch resistance more than glass fibers. Increased scratch repetitions lead to fiber breakage and material loss. Hybrid fiber layers distribute load and minimize surface damage. Strong fiber‐matrix adhesion is crucial for reducing damage severity. Research informs the design of durable, fiber‐reinforced composites.

Parametric optimization in drilling of sisal–glass reinforced epoxy composites using Taguchi grey relational analysis method

This research work intends to study the effect of hybridization of glass and sisal fiber, stacking sequence and tensile properties of the composite. The sisal-glass fiber hybrid composites laminates are prepared using reinforced plain woven sisal fabric (unidirectional) and plainwoven glass fabric. In this research study, 27 experiments are conducted as per L27 orthogonal array. Five process parameters are selected and three responses are considered in this work. The drilling of the composite specimen is considered and the drilling process parameters such as speed, feed rate, drill diameter, material thickness, and drill point angle are selected. The responses considered in this work are delamination factor, thrust force, and torque. Taguchi analysis is performed and the response table for means for the responses is determined, and the most influencing parameter in the drilling of the composite specimen is analyzed. The grey relational coefficients are computed and followed with the computation of the grey relational grade. The grey relational grades are calculated for determining the highest contributing parameter in the drilling of the sisal fiber and glass fiber reinforced hybrid composite specimen. The optimum drilling process parameters are ranked and the ranks presented represent the sequence of run resulting in optimum solutions.

On the bending behavior of hybrid fiber–metal laminates (HFMLs) based on aluminum and glass/Kevlar fibers reinforced epoxy

In this work, the mechanical behaviors under flexural loading of fiber–metal laminates (FMLs) comprised of an aluminum alloy reinforced with glass fibers (GFs) and Kevlar fibers (KFs) embedded in an epoxy composite are experimentally investigated. For this purpose, non-FMLs, FMLs, and hybrid FMLs (HFMLs) are tested and their results are compared in terms of the flexural strength and modulus, strain to failure, toughness, interlaminar shear strength (ILSS), and specific properties. Results show that the incorporation of GFs on the compression side and KFs on the tensile side improves the bending properties of the HFMLs compared to the KF-based FMLs, which enhances the laminates’ resistance to bending loads. The HFMLs exhibit improvements of 24%, and 5% in flexural strength and modulus, respectively, compared to the KF-based FMLs. Moreover, hybridization significantly improves strain to failure by up to 115% compared to the GF-based FMLs. Additionally, the ILSS analysis reveals improved values in FMLs compared to non-FML samples, when GF-based FMLs demonstrate higher ILSS than KF-based ones, which can be attributed to GFs’ stiffness and high-quality bonding with the aluminum sheets. HFMLs attain a 19% improvement in ILSS compared to the KF-based FMLs. The failure mechanism depends on the intrinsic features of the studied fibers, while the studied FMLs display better damage tolerance. In this context, the HFMLs present enhanced toughness, delamination resistance, and the ability to prevent crack propagation, positioning them as promising candidates for lightweight structural applications where a balance between strength, stiffness, and toughness is required.

Experimental investigation on impact strength of hybrid fibre reinforced concrete containing steel and polypropylene

Experimental investigation on impact strength of hybrid fibre reinforced concrete containing steel and polypropylene

Compact hundred-watt level picosecond laser system based on tapered double cladding fiber-single crystal fiber hybrid amplifier

This paper introduces a compact picosecond laser system using tapered double cladding fiber-single crystal fiber hybrid amplification technology for the first time. By modifying the Ginzburg-Landau equation, we established a simulation model and designed a passive mode-locked picosecond oscillator based on a semiconductor saturable absorber mirror. The oscillator outputs laser with a pulse width of 7.75 ps, a center wavelength of 1030.55 nm, and a spectrum width of 0.58 nm. The seed laser is stretched and amplified by the all-fiber front stage, and then injected into the tapered double cladding fiber-single crystal fiber hybrid amplifier. The laser power is amplified from 820 mw to 103.1 W, obtaining a gain of 21 dB. We used zero-phonon line pumping technology in single crystal fiber amplifier to reduce the thermal effects caused by quantum loss, thereby increasing the length of the crystal and increasing the power loading capacity. We designed a single crystal fiber amplification module using Yb:YAG with 60 mm long, 1 mm diameter and a 1 at.% doping rate for the first time. Finally, a hundred-watt level picosecond laser output with a repetition frequency of 26.33 MHz, an average power of 103.1 W, a pulse width of 244.72 ps, a spectrum width of 1.16 nm, and a beam quality of M2 x = 1.368 and M2 y = 1.511 was obtained. To the best of our knowledge, this is the highest picosecond laser output power for an all-fiber front-stage combined with a single-stage single crystal fiber amplifier.

Highly Stable Heating Fibers of Ti3C2Tx MXene and Polyacrylonitrile via Synergistic Thermal Annealing.

Nanohybrid assemblies provide an effective platform for integrating the intrinsic properties of individual components into microscale fibers. In this study, a novel approach for creating mechanically and environmentally stable MXene fibers through the synergistic assembly of MXene and polyacrylonitrile (PAN), is introduced. Unlike fibers generated via a conventional stabilization process, which relies on air-based stabilization to transform the PAN molecules into ring structures fundamental to carbon fibers, the hybrid fibers are annealed in an Ar atmosphere. This unique approach suggests MXene can serve as an oxygen provider that is essential for stabilizing PAN. As a result, significantly improved interfiber compactness is achieved and the oxidation stability of MXene is enhanced under atmospheric conditions. The resulting fibers exhibit exceptional stability, even after extended exposure to high humidity and elevated temperatures. This highlights the suitability of the thermally annealed MXene-PAN (T-MX-PAN) fibers as robust electric heating elements. Notably, these fibers consistently generate heat over 1800 bending cycles. When integrated into fabrics, they demonstrate the capability to generate sufficient heat for melting ice and rapid evaporation. This study highlights the potential of T-MX-PAN fibers as next-generation wearable heaters and offers valuable insights into advancing wearable technology in demanding environments.

Thermal Properties of Natural and Hybrid Fiber Reinforced Composites

Thermal Properties of Natural and Hybrid Fiber Reinforced Composites

Permeability testing and mechanism analysis of aramid fiber hybrid fabrics

Aramid fiber composites have exceptional mechanical and insulating properties and are used in ultra-high-voltage power transmission. Fabric permeability is crucial for controlling composite defects. At present, the effective method to improve the permeability of aramid fibers is the hybridization of fiber fabrics. This study investigates permeability tests and impregnation mechanisms of aramid fiber fabric and its hybrid fabric. The permeability of the aramid fiber fabric and the hybrid fiber fabric was measured using a camera and a pressure sensor. The permeability of the fabric was analyzed by observing the structure, surface topography, dynamic contact angle, and surface free energy. The results show that the dynamic contact angle can be reduced and the surface free energy can be increased by hybridizing the fibers and the wettability of the fiber fabric is improved. Compared to an aramid fiber fabric, the in-plane permeability of aramid/glass fiber interlayer hybrid fabric increases by 36.19%, while the in-plane permeability of aramid/glass fiber intralayer hybrid fabric increases by 64.97%. The out-of-plane permeability of aramid/glass fiber interlayer hybrid fabric increases by 16.79%, while the in-plane permeability of aramid/glass fiber intralayer hybrid fabric increases by 30.1%. This study offers theoretical guidance for aramid fiber composite manufacturing and simulation input parameters.

Experimental investigation on the mechanical properties of cement mortar containing recycled tire crumbs reinforced with polypropylene, oil palm and banana fibers

The automotive industry discards a large number of end-of-life tires annually, creating a growing global environmental hazard. The incorporation of crumb rubber derived from waste tires into construction materials is considered one of several alternatives for sustainably reusing these waste materials. The addition of fibers as reinforcements would address the typical degradation caused by the crumb rubber in cement composites. Fibers sourced from plants and recycled synthetics offer a practical and eco-friendly reinforcement material that is both cost-effective and easy to procure. However, two challenges emerge from these choices. Firstly, natural fibers exhibit substantial regional variations, resulting in differences in their properties and inconsistent performance. Secondly, recycled materials also demonstrate variation due to disparities in production and manufacturing processes. As a result, incorporating these fibers into cement-based materials has produced conflicting outcomes due to these inherent variations, rendering practical application unfavorable. Therefore, this study attempts to promote the adoption of sustainable practices by addressing the lack of available performance-based data for the utilization of these fiber variants in the design of cement mixtures. The data would allow engineers to integrate these mixtures into commercial designs for practical in-situ construction. A total of 18 novel cement-based mixtures containing different types of fibers, chemical admixture, and discarded crumb waste were formulated and evaluated in fresh and hardened properties. A multifaceted approach was also undertaken to further hybridize the fibers and quantify the synergistic effects within the investigated cement matrice. The results indicate that the incorporation of polypropylene and oil palm fibers enhances compressive and tensile strength, although there is a general weakening observed in flexural strength. In the case of hybrid fibers, a successful combination of polypropylene and banana fibers is evident, showing a positive hybrid effect coefficient compared to a negative coefficient for polypropylene-oil palm fiber combinations.