Addition Of Fibers Research Articles

Experimental Investigation on Partial Replacement of Cement by Silica Fume and Fine Aggregate by Quarry Dust with Addition of Basalt Fibre

The main aim of this project is to found a suitable alternative for the natural river sand, which is reaching maximum level of scarcity. M-sand is used along with the addition of natural basalt fibres in to the concrete. In this study, the experimental investigation on basalt fibre silica fume concrete (BFSFC) was discussed. The variables of study include the Basalt fibre content (0.25%, 0.3%, 0.35% and 0.4%). The 30% of quarry dust as replacement for sand and 10% of Silica fume as cement replacement are incorporated in all the concrete mix proportions considered in this study. The test results indicate that physical properties of materials such as sieve analysis, specific gravity and water absorption. The mix design is done for the grade of M30 concrete. The mechanical properties of concrete such as compressive strength, split tensile strength and flexural strength will be obtained and the strength of control concrete and basalt fibre silica fume concrete will be compared.

An experimental study on the strength values of resin added sand samples with different types of fiber reinforcements

In this study, uniaxial compressive strength values of a sand type soil reinforced with polypropylene fiber and silicate-based resin additives with different amounts were investigated. Micro grid fiber (MGF) was tested as a new polypropylene fiber additive in the experiments to compare it with a widely used polypropylene fiber type geosynthetic product used in soil fill improvement applications. According to the findings obtained from the uniaxial compressive strength (unconfined compressive strength) tests, it was determined that the new MGF type fiber usually increased the strength values at higher rates in comparison with the conventional fiber product. As another outcome, it was found that target strength values can be supplied by using less resin amounts for the specimens with fiber additives. It was determined that proper strength improvements can be obtained more economically by the fiber additive use together with the resin, rather than the resin added mixtures without the fiber.

Sokasi Commodity Production: The Utilization of Bamboo Stem Fiber Composite to Create Balinese Local Products

This research aims to determine the optimal combination of a mixture containing bamboo fibre and polyester resin, with the addition of coconut fibre as a reinforcing material. The main objective of this research is to test tensile tests to determine the most suitable strength factor. In addition, this research aims to evaluate how changes in specific parameters affect the tensile characteristics of composite materials. The parameters observed include the proportion of the matrix to the volume of coconut fibre, the percentage of alkali concentration, and the length of the coconut fibre. The composite fabrication stage involves using the hand lay-up and Taguchi methods. The reason for choosing the L4(23) orthogonal experimental design is that there are three process parameters, each with two levels. The trial was duplicated five times. Important factors studied include the ratio of matrix and volume of coconut fibre, alkali concentration, and length of coconut fibre. Based on the results obtained from this research, it has been proven that the most effective combination to achieve the highest tensile strength is a matrix that accounts for 60% of the composition, coconut fibre occupies 20% of the volume, and an alkali concentration of 5.%, and coconut fibre strands measuring 30 mm long. The tensile strength test result of this particular composition was 54.34 MPa. Apart from that, the length of coconut fibre is the most significant factor in increasing tensile strength, with a contribution of 42.560%.

Fractal Characteristics of Natural Fiber-Reinforced Soil in Arid Climate Due to Cracking

Fractal geometry is a geometry that focuses on irregular geometric forms and can quantitatively describe rough and uneven surfaces and interfaces. As the main material for making natural fiber geotextile, rice straw fiber can reduce the direct impact of rainfall on soil and reduce the intensity of hydraulic erosion. This study investigates whether the use of rice straw fiber as an additive to reinforce arid soil can inhibit moisture evaporation and prevent cracking. Samples with different fiber contents added (0%, 1%, 2%, and 4%) are placed in an environmental chamber to simulate the effects of an arid climatic condition and control the temperature and humidity levels. The cracking process of the samples is recorded by using a digital camera, and the parameters of the evaporation and cracking processes are quantitatively examined through digital image processing. The results show that all of the samples with fiber have a higher residual water content and can retain 31.4%, 58.5%, and 101.9% more water than without the fibers, respectively. Furthermore, both the primary and secondary cracks as well as crack networks are inhibited in samples with a higher fiber content, that is, 2% or 4% fiber contents. The samples reinforced with fiber also have a smaller crack ratio. Compared with the samples without straw fiber, the final crack ratio of the samples with 1%, 2%, and 4% fiber is reduced by 8.05%, 24.09%, and 35.01% respectively. Finally, the final fractal dimensions of the cracks in samples with fiber contents are also reduced by 0.54%, 5.50%, and 6.40% for the samples with 1%, 2%, and 4% fiber, respectively. The addition of natural fiber as an additive to reduce evaporative cracking in soil can: (1) reduce the soil porosity; (2) enhance the binding force between the soil particles; and (3) block the hydrophobic channels. Therefore, the addition of rice straw fiber to soil can effectively reduce soil evaporation and inhibit soil cracking.

Application of waste rice straw as fibre or filler in asphalt mixtures: materials characterisation and performance evaluation

ABSTRACT This study investigated the application of agricultural waste rice straw as fibre or filler in asphalt mixtures. Initially, the physical, chemical, mineralogical and morphological characterisation of rice straw products were analysed. Subsequently, the performance of stone matrix asphalt (SMA) mixtures containing rice straw fibre was evaluated in terms of rutting, crack resistance and moisture susceptibility, compared to cellulose fibre. Additionally, the properties of asphalt concrete (AC) mixtures incorporating rice straw filler to replace conventional mineral filler partially were examined. The findings revealed that rice straw products exhibited similar characteristics to cellulose fibre or mineral filler, indicating their suitability for use in asphalt mixtures. The appropriate addition of rice straw fibre or filler demonstrated enhancement in the high-temperature performance, low-temperature crack resistance and moisture stability of asphalt mixtures. Through experimental tests, the optimum content of rice straw fibre in SMA-13 mixtures was determined to be 0.4%, while for the rice straw filler in AC-13 mixtures, it was 20%. The mechanisms of rice straw fibre and filler added in asphalt mixtures to strengthen their road performance were binder adsorption and reinforcement effect through scanning electron microscope (SEM) images. Furthermore, rice straw filler also contributed to void filling within asphalt mixtures.

Structural Behavior of Circular Concrete Columns Reinforced with Longitudinal GFRP Rebars under Axial Load

This paper presents experimental and theoretical assessments of the structural behavior of circular steel fiber-reinforced concrete (SFRC) columns reinforced with glass fiber-reinforced polymer (GFRP) bars subjected to a concentric axial compressive load. Laboratory experiments were planned to evaluate and compare the effect of different design parameters on the structural behavior of column specimens based on experiments and finite element (FE) analysis. The experimental variables were (i) concrete types, i.e., conventional concrete (CC) and fiber-reinforced concrete (FC), (ii) longitudinal reinforcement types, i.e., steel and GFRP bars, and (iii) transverse rebar configurations, i.e., tied and spiral with different pitches. Sixteen column specimens were fabricated and categorized into four groups with respect to rebar configurations and concrete types. The results showed that the failure modes and cracking patterns of those four column groups were comparable, particularly in the pre-peak branches of load-deflection curves. Even though the average ultimate load of the columns with longitudinal GFRP bars was 17.9% less than that with longitudinal steel bars, the ductility index (DI) was 10.2% greater than their counterpart on average. The addition of steel fibers (SF) to concrete increased the axial peak load by up to 3.1% and the DI by up to 6.6% compared to their counterpart CC columns without SFs. The DI of specimens was increased by higher volumetric ratios (up to 12%) and spiral types (up to 5.5%). The concrete damage plastic (CDP) model for FC columns was updated in the finite element software ABAQUS 6.14. Finally, a new simple equation was theoretically proposed to predict the axial capacity of specimens by considering the inclusion of longitudinal GFRP rebars, volumetric ratio, and steel spiral/hoop ties. Good agreement between the proposed model predictions and the experimental/numerical results was observed.

Effect of Fire Exposure on the Properties of Self-Compacting Concrete reinforced by Glass Fibers

The optimal design of any structural elements requires examining all environmental risks, emergency accidents, and standard load cases. Exposure to fire is one of the most common safety threats. Nowadays wide developments are achieved in the field of concrete technology, therefore, experimental and theoretical investigations should be performed on the characteristics of such developed materials under different loading conditions. This study investigates the impact of fire exposure on the mechanical characteristics of self-compacting concrete, specifically compressive and tensile strength, modulus of elasticity, and stress-strain relation. The adopted fire exposure consisted of six steady-state temperatures (300, 400, 500, 600, 700, and 800°C) for one hour and a sudden cooling method. Four glass fiber volume fractions were adopted: 0, 0.5, 1, and 1.5%. The glass fiber volume fractions considered (0.5-1.5%) improved the mechanical properties investigated. Two states were detected for the effect of fire exposure. The effect of fire exposure was inversely proportional to fiber content in burning temperatures of 300-700°C, while the reduction in mechanical properties of 1.5% fiber content was greater than those of 0.5 and 1% when the temperature increased to 800°C. Furthermore, the addition of glass fiber changed the brittle mode stress-strain relation to semi-ductile for the non-burned and burned up to 600°C specimens, whereas a brittle behavior was detected when the temperature increased above 600°C. In general, a similar effect was noticed for all the glass fiber ratios considered regarding the slope of the stress-strain linear stage compared to the non-burned specimens, which was more salient when the burning temperature increased.

Investigation of Maximum Mid-Span Displacement and Reaction Forces in Fiber-reinforced Concrete Beams subjected to Impact

Self-Compacting Fiber-Reinforced Concrete (SCFRC) is a specialized type of concrete that combines the properties of Self-Compacting Concrete (SCC) with the addition of fibers for reinforcement. SCFRC is designed to have excellent flowability and self-leveling characteristics while providing enhanced tensile strength, ductility, and crack resistance. This paper presents a discussion on the topic of SCFRC and the impact load behavior of SCFRC beams reinforced with Waste Plastic Fibers (WPFs). A comparison with reinforced concrete beams without fibers is also conducted. This study aims to predict the maximum mid-span displacement and the maximum reaction force of the fiber concrete beams under impact load. Twelve beams that represent the total adopted parameters were tested under impact loading. The beams were divided into three main groups according to the longitudinal steel ratio. The steel ratio was varied by using steel bars of 10, 8, and 6 mm diameter, with PET waste fibers with different volume ratios Vf% of 0, 0.5, 0.75, and 1%. The results showed that the use of beams is reinforced with ρmax, ρmax< ρ< ρmin, and ρmin having reduced maximum deflection by 24.23%, 35.9%, and 46.28%, respectively, when using WPFs with a volumetric value of 1%. This paper also covers work steps, model details, and the tests that were carried out on the specimens, which were made from materials available in local markets.

Experimental study and modelling of flexural behaviour of continuous fibre-reinforced lightweight aggregate concrete one-way slab at ambient and elevated temperatures

An experimental study on the flexural behaviour of six fibre-reinforced lightweight aggregate concrete (FRLWAC) one-way slab strips under ambient and elevated temperatures is presented in this paper. Two slabs, one simply-supported and one continuous, were loaded to failure at ambient temperature as references for the fire tests, while another simply-supported and three continuous slabs with varying degrees of design moment redistribution were loaded and exposed to elevated temperatures until failure. The ambient tests showed that the steel fibre addition prevents premature flexural-compression failure commonly observed in lightweight aggregate concrete structures. The rotations of FRLWAC plastic hinges were concentrated in a single crack under ambient temperature and a few cracks under fire exposure. The fire tests revealed significant moment redistribution towards the hogging moment area in the continuous slabs due to restrained thermal-induced deflection. Furthermore, the reinforcement configuration that catered for moment redistribution towards the hogging area was found to enhance the fire resistance of continuous FRLWAC slabs. A fibre-reinforced concrete (FRC) plastic hinge model, based on the rigid-body rotation concept, was proposed and validated. This model predicts the moment-rotation behaviour of FRC hinges at ambient temperature and the fire resistance of FRLWAC one-way slabs with good accuracy.

Mechanical characteristics of waste-printed circuit board-reinforced concrete with silica fume and prediction modelling using ANN.

The use of electronic waste in cement concrete as a fibre additive has proven to be very promising for improving mechanical characteristics and developing sustainable construction materials to reduce the waste dumped in landfills. The following study investigated the effect of electronic waste (printed circuit boards (PCBs)) on the mechanical properties of concrete and predicted the same properties with an appropriate machine learning technique. PCB fibres 45mm in length and 1.5mm in width were manufactured and added as fibre additions to two sets of concrete mixes with and without silica fume. A 10% volume replacement of cement was substituted with silica fume (SF) to enhance the characteristics of PCB fibre-reinforced concrete and minimize cement consumption. The study included an evaluation of the fresh properties and mechanical characteristics after a 28-day curing period; thereafter, the results were compared and studied using the Levenberg-Marquardt backpropagation algorithm for predictions. The results show that the mechanical properties improved up to a 5% addition of PCB fibres, resulting in strengths of 63.55MPa and 69.92MPa for mixtures of PCB5% and SFPCB5%, respectively. A similar trend was achieved for other properties, such as the tensile and flexural strengths. The results of the ANN model predicted values with R2 values ranging from 0.94 to 0.99, indicating the efficacy of the model.

False banana fiber reinforced geopolymer composite – A novel sustainable material

A new geopolymer composite material was produced using low-calcium fly ash and false banana plant fiber. The effect of fiber content and length on the mechanical and microstructural properties of the resulting composite material was investigated. Results showed that the addition of alkali-treated false banana fiber significantly improved the compressive and splitting tensile strength of the composites. In particular, incorporating a 10 mm length fiber at a 1.4 % volume fraction increased compressive and splitting tensile strength by 31 % and 33 %, respectively, when compared to the pure geopolymer paste specimens. Furthermore, unlike the neat geopolymer paste specimens, all composites failed gracefully. In addition to this, FTIR absorption peaks and SEM micrographs demonstrated that alkali treatment effectively changes fiber morphology and chemical characteristics. Additionally, fiber pull-out, fiber bridging, and fiber fracture were identified as energy-absorbing mechanisms responsible for increasing the mechanical properties of the composites. In general, the results showed that using natural false banana fiber as reinforcement enhances the mechanical properties of geopolymer composites, making them a more environmentally friendly alternative to synthetic fibers in composite production.

Corrosion Resistance of Reinforcing Steel in Concrete Using Natural Fibers Treated with Used Engine Oil

The addition of natural fibers in the elaboration of concrete pastes has increased as an innovative alternative for the development of more ecological and environmentally friendly constructions. The objective of this research is to incorporate natural fiber residues from palm leaves and mango stone impregnated with used engine oil (UEO) in the cement matrix to improve the mechanical and electrochemical properties of reinforced concrete. Samples with fiber percentages of 0.2% and 0.4% with respect to the weight of the sand with a length of 10 mm were fabricated. Their properties, such as workability, air content, porosity, and compressive and flexural strength, were analyzed. To understand the corrosion rate of the steel bars, electrochemical techniques of corrosion potential, electrochemical noise, linear polarization resistance, and electrochemical impedance spectroscopy were applied to cubic samples exposed in a 3% sodium chloride saline environment for 365 days. The experimental results showed a positive effect on the corrosion phenomenon with the UEO and mango fiber treatment, decreasing the corrosion rate due to the formation of a protective film at the steel/concrete interface. Doi: 10.28991/CEJ-2024-010-04-02 Full Text: PDF

A Study of the Effect of Addition of Nano SiO2 and Polyamide Fiber toward Swelling Potential Expansive Clay

Expansive clay with great swelling potential requires improvement or stabilization of the soil. It can be successfully done by mechanical and chemical stabilization techniques. This study aims to determine the effect of adding Polyamide (PA) fibre as the material for mechanical stabilization and nano SiO2 as the material for chemical stabilization. The expansive clay used in this study deployed a sample of clay containing mineral montmorillonite with the USCS classification in the high plasticity (CH) category. The mixed materials used include PA fibre with variations of 0.5%, 0.75% and 1% by weight of dry soil and nano SiO2 with variations of 1%, 2% and 3% by dry soil weight. To prove the effectiveness of using nano SiO2, this study compares the treatment with the use of micro SiO2 materials under the same comparison variations. This result indicates that the expansive clay that has been stabilized using PA fibre and nano SiO2 is capable of preventing the swelling potential.

Feasibility Study on the Use of Iron Ore Tailings as Fine Aggregate with Glass Fibre in Concrete

Concrete is the most widely used building material in the world, but its production has significant environmental consequences, including high carbon emissions and natural resource depletion. As a result, there is an increasing interest in the development of sustainable concrete technologies that reduce concrete’s environmental footprint while maintaining its performance and durability. Partially replacing fine aggregate with industrial waste is one such approach. It is a great practice for developing sustainable concrete that can help with environmental problems caused by the dumping of these waste materials at the same time maintaining the performance of concrete. It also provides economic and social benefits in addition to the environmental benefits. iron ore tailings is one such industrial waste that is the by-product of iron ore beneficiation process which has shown the potential for partial replacement of fine aggregate in concrete. In addition, glass fibre is added to improve the tensile property of concrete. A concrete mix of M20 grade were prepared by replacing fine aggregate with iron ore tailing at replacement level 15%, 25%, and 35% and the optimum replacement percentage was obtained. Further, glass fibre was added at the dosage of 0.5% by the weight of cement to the mix with optimised replacement of iron ore tailings and tests were conducted. This work also examines concrete’s physical, mechanical and durability properties with partial replacement of fine aggregate with iron ore tailings and glass fibre by conducting tests on strength and durability. Results obtained indicates incorporation of iron ore tailing with concrete reduces the workability of concrete, and the addition of glass fibre improved the compressive strength and split tensile strength. Durability tests show an increase in water absorption with the addition of iron ore tailings and a medium level of chloride penetration. The study showed the use of iron ore tailing as a sustainable alternative to fine aggregate in concrete.

Stress Analysis on Mesiolingual Cavity of Endodontically Treated Molar Restored Using Bidirectional Fiber-Reinforced Composite (Wallpapering Technique).

Endodontically treated teeth (ETT) undergo extensive structure change and experience high stress during biomechanical function. Stress distribution is influenced by the restoration material and the type of bond between material and tooth structure. The selection of materials that can distribute stress will affect the resistance and retention of ETT to mastication forces, thus biomechanical functions were achieved. Composite has mechanical properties similar to dentin, it can transmit and distribute stresses throughout the tooth surface. The disadvantage of composites in large cavities is their lack of toughness. The addition of fiber to composites can increase their toughness. This research is to determine the stress distribution of a fiber-reinforced composite made of polyethylene and e-glass on the mesiolingual cavity of ETT. A three-dimensional model of the mandibular molar was prepared for cavity preparation and the formation of restorations using SolidWorks 2021. The models were analyzed with Abaqus 2020 to determine stress concentrations after given vertical and oblique loading. The maximum and minimum principal stress data were obtained to assess material resistance and interfacial damage criterion. Polyethylene fiber shows a more homogeneous stress distribution because the modulus of elasticity is close to the dentin and has a thickness that can reduce the volume of the composite. The E-glass shows the stress concentration on the circumferential fiber and cavity floor. The stress distribution of fiber-reinforced composite on the buccolingual cavity of ETT using the finite element method did not show structural failure in the polyethylene group because the maximum and minimum principal stresses were lower than the strength of the material. Interfacial bond failure occurs at the enamel portion. The maximum and minimum principal values of e-glass indicate structural failure in the circumferential fiber and the base fiber because the stress exceeds the strength of the material. Interfacial bond failure occurred on the circumferential and the cavity floor.

Highly porous carbon-SiC composites with continuous carbon fibers for the production of radioisotopes in ISOL facilities

New C/SiC composites with continuous fibers were produced through impregnation of carbon fiber preforms and consolidation by hot pressing. The resulting sintered material was investigated as a potential target for nuclear applications, such as radioisotope production. Desired properties include high porosity and high thermal conductivity to allow isotope release from the targets while working at high temperature. To this end, porosimetry and thermal and mechanical characterizations were conducted up to 1250°C. It was shown that the addition of fibers resulted in high porosity, about 40%, while maintaining a very high thermal conductivity, 40 W/m∙K at 1250°C, a value particularly attractive for the intended application. Emissivity at 1250°C was 0.76, compressive strength at room temperature was 134 MPa, and flexural strength passed from about 90 MPa before thermal conductivity measurements to 50 MPa after the tests.

Engineering Properties of Cement-Paste with Polypropylene and Carbon Fibres

Concrete has strong compressive strength, but it is brittle and vulnerable to tension-induced failure. To address the issue, this research investigated the effect of the addition of fibre on the engineering properties of cement paste. There were two fibres examined in this study, which include polypropylene fibre (PF) and carbon fibre (CF). The engineering properties that were studied include flowability, hardened density, compressive strength, and flexural strength at 7, 28, and 56 days. The results indicated that the addition of fibre had only subtle effects on workability, attributed to a judiciously chosen low-volume fraction of fibres. Notably, a consistent increase in hardened density, compressive strength, and flexural strength was observed over the curing period, driven by ongoing hydration processes. Therefore, it can be concluded that the incorporation of PF and CF significantly improved cement paste engineering properties, outperforming the control specimen in hardened density, compressive strength, and flexural strength.

SOUND AND THERMAL INSULATION PROPERTIES OF SANDWICH COMPOSITES MADE OF WASTE KEVLAR® MATERIALS

This paper examines the thermal and acoustic insulation characteristics of sandwich composites with waste Kevlar® fiber-reinforced face materials and polyurethane/paper cardboard cores. Waste Kevlar® short fibers (carding waste) were reinforced into the sandwich composites’ core part in varying ratios (2%, 5%, and 10%). Kevlar® fabric edge waste (waste of weaving process) was used to produce the face materials of sandwich composites. Sandwich composites were also stitched using Kevlar® yarns to observe the effect of the through-thickness reinforcement on sound and thermal insulation properties. The sound insulation test results showed that reinforcement of short Kevlar® fibers into the core parts of sandwich composites somewhat raised their sound absorption coefficients. Because the stitching holes created air spaces for sound vibrations, the sound absorption coefficient values improved. The sound transmission losses of sandwich composites were also increased up to 30 dB after short Kevlar® fiber addition. The thermal conductivity coefficient of sandwich composites decreased, indicating that the addition of Kevlar® fibers increased their insulation properties.

Experimental Study of Compressive Strength and Tensile Strength of Foam Mortar with the Addition of Polyethylene Fibers

Mortar is a building material of sand, cement, and water that is stirred until homogeneous. So that a light mortar can be obtained, this can be done by mixing the mortar with a foaming agent. Adding polyethylene fiber increases the compressive strength, tensile strength, modulus of elasticity, and brittleness of lightweight mortar. The percentage of added fiber is 0%, 0.25%, 0.5%, 0.75% and 1%. The average density of lightweight mortar added with polyethylene fiber is 895.316 kg/m3. The optimal compressive strength with a fiber ratio of 0.5% polyethylene fiber is 3461.429 kPa, an increase of 172.906% compared to 0% polyethylene fiber. The optimal tensile strength of 0.5% polyethylene fiber is 1218.384 kPa, an increase of 364.917% compared to 0% polyethylene fiber. Based on the results of foam mortar experiments using a foam agent with polyethylene fiber, this is classified as type O mortar, not recommended for interior and exterior walls that do not support structural loads.

Study on stress–strain relationship and constitutive model of recycled aggregate concrete under axial cyclic compression

AbstractThe effects of dry or saturated state, water–cement ratio, coarse aggregate type and steel fiber on the stress–strain relationship of RAC under cyclic loading were studied. What is more, the characteristics of stress–strain curve, plastic strain, stress degradation and stiffness degradation of RAC under cyclic loading were analyzed. The microstructure of RAC was analyzed. Based on the principle of surface energy, the reason for the decrease in compressive strength of wet concrete was analyzed. In addition, the envelope equation of stress–strain curve under cyclic loading, unloading and reloading curve was established. The test results showed that the peak stress of the envelope line of RAC under cyclic loading was affected by dry or saturated state, water–cement ratio and coarse aggregate type, but the addition of steel fiber could reduce the degradation rate of stress and stiffness of RAC after peak strain. The plastic strain accumulation of RAC before and after the peak stress was quite different, but dry or saturated state, water–cement ratio, coarse aggregate type and steel fiber have no obvious influence on the plastic strain accumulation of RAC. The pores and cracks of RAC provide space and channels for the moisture absorption and water absorption. The Weibull–Lognormal statistical distribution envelope model, unloading curve model and reloading curve model established were in good agreement with the experimental curves. The research results provided a reference for the study of the full curve constitutive model of RAC under cyclic loading.