Amount Of Fibers Research Articles

Flexural Strength of Light-Weight Steel Fiber Reinforced Concrete Containing Biodegradable LDHs Microparticles: Experimental Study and Multiscale Finite Element Model

This study investigates the influence of LDHs (Layered Double Hydroxides) microparticles and steel fibers on the mechanical properties of lightweight concrete. Through a combination of experimental analysis and finite element modeling, the effects of LDHs and steel fibers on flexural strength and crack resistance were evaluated. The experimental results demonstrate a significant increase in flexural strength and toughness with the incorporation of LDHs microparticles and steel fibers. The finite element model corroborates these findings, highlighting the synergistic enhancement of mechanical properties due to LDHs and steel fibers. Additionally, the study discusses the frontier applications of LDHs in improving fracture characteristics and highlights the potential of hybrid reinforcement strategies in lightweight concrete. The findings reveal that both the quantity of microparticles and steel fibers significantly impact the concrete's residual strength. In scenarios without steel fibers, an optimal weight fraction of approximately 1 wt.% LDHs demonstrate a 39% increase in bearing capacity. Notably, under comparable conditions, the influence of LDHs microparticles on enhancing concrete mechanical characteristics appears to surpass the effects induced by steel fibers. However, at 2 wt.% LDHs usage, a decrease in load capacity by 3.3% is observed compared to the 1 wt.% LDHs configuration. This research provides valuable insights into optimizing concrete properties through novel material combinations and paves the way for future advancements in structural engineering.

Evaluation the Ingredients and Influence of Thermal Treatment on Physicochemical Properties and Bioactive Compounds of Evernia prunastri from Algeria

Background: Lichen is a symbiotic organism with unique structure composed of a fungal partner and an algal partner. It has been utilized in folk foods and medicines. The objective of the present study was to analyze the ingredients and the impact of heating on various physicochemical and phytochemical characteristics of a 500 g sample of lichen Evernia prunastri from Jijel, Algeria collected in May 2021. Methods: The nutritional value of the lichen was determined by studying various parameters. The metal contents were analyzed using an Atomic Absorption Spectrophotometer. The effect of heating (70 and 100 °C) on the physicochemical parameters, and bioactive compounds of aqueous extracts obtained by maceration in distilled water was studied. Statistical analysis was performed using ANOVA. Results: A high percentage of carbohydrates (64.00%) were observed in the lichen material. Pectin, fats, and crude proteins levels were low. High ash content (10.85%) was obtained with the presence of metal elements. Preliminary phytochemical analysis indicated the presence of polyphenols and flavonoids with 51.13 mg Gallic Acid Equivalent (GAE)/100 g and 17.87 mg Quercetin Equivalent (QE)/100 g of lichen, respectively. The lichen sample subjected to 70 °C demonstrated an increase in the parameters examined, with the exception of proteins and vitamin C. Conversely, the lichen sample treated at 100 °C exhibited a reduction in vitamin C, protein, and bioactive compound content, as well as an increase in sugar content. Titratable acidity and pH parameters were unaffected. Conclusion: The appreciable quantities of carbohydrates, crude fibers, and other compounds in this lichen suggest a potential use for these active ingredients in the preparation of functional food. Heating to 70 °C produces a preparation enriched in bioactive substances and sugars. However, heating to 100 °C, exposes the various tissues to degradation, potentially leading to a decrease in nutrients

Preparation and Engineering properties of Slurry Infiltrated Fibrous Concrete (SIFCON) -A Review

This paper discusses the preparation of SIFCON and its important characteristics . Previous studies have shown that SIFCON has improved ductility , strength and durability . The paper also highlights different material that can replace cement ,such as silica fume ,fly ash with different percentage and different of steel fiber of over 4% can be used .Many previous investigation have shown that there is a significant relationship between the strength of concrete and the mortar and fiber mixture used in term of size and type .It has also been found that when using an amount exceeding 5% of fibers, certain steps should be followed in casting specimens . These steps including using fine sand less than 1 mm in size to create suitable cement slurry and replacing up to 30% of the cement with pozolana material to create cement slurry that can penetrate and interlock with fibers of all forms and volumes . Finally, the research offers a concise overview of concrete properties and their significance in addition analyzed the impact of fiber quantity increase on the density and various properties of concrete , including its compressive and tensile strength as well as energy absorption Additionally , its inspected how concrete responds to external element like exposure to sulfate attack , acids and fire.

Ponašanje tijekom sloma izvana pojačanih armiranobetonskih greda s primjesom krutih vlakana

In recent decades experimental investigations on fibre reinforced polymer (FRP) laminate-strengthened reinforced concrete (RC) beams have been extensively conducted. It has been found effective in flexural and shear strengthening perspectives. On the other hand, a primary problem frequently encountered in such technique is the separation of FRP laminate with the concrete bonded surface. Such failures are due to the formation of localized flexural and otherwise shear cracks in the fragile region of the FRP-concrete interface. The debonding occurrence also significantly affects the strength enhancement of the laminated beams. The emphasis of the study is to enhance the potential performance of externally FRP strengthened RC beams by incorporating an effective crack controlling agent, that is ‘rigid hooked-end steel fibres’ in the matrix. Nine RC beams were cast and tested in this study with variables including different quantities of hooked-ends steel and glass fibre reinforced polymer (GFRP) thickness. The pre-cracking and post-cracking behaviour of the externally FRP strengthened RC beams mixed with the short fibres were systematically evaluated and improved performance at various stages of cracking was found. Another finding is the transformation of failure pattern from brittle to ductile due to exceptional strain-hardening phenomenon caused by steel fibres in the strengthened RC beams, in comparison to that of other beams without steel fibres. The formations and propagations of the cracks at different stages were numerically modelled for all the beams using the ANSYS and compared the numerical design validation with the experiment.

The Different Properties of Geopolymer Composites Reinforced with Flax Fibers and Carbon Fibers.

The main motivation for this research was to improve the properties of geopolymers by reinforcement using synthetic and natural fibers, and to gain new knowledge regarding how the nature and/or the quantity of reinforcement fibers influences the properties of the final geopolymers. The main objective was to investigate the effects of different types of reinforcement fibers on the properties of the geopolymers. These reinforcement fibers were mainly environmentally friendly materials that can be used as alternatives to ordinary Portland cement. The authors used fly ash and river sand as the raw materials for the matrix, and added carbon fibers (CF), flax fibers (FF), or a hybrid of both (CFM) as reinforcements. The samples were prepared by mixing, casting, and curing, and then subjected to various tests. The main research methods used were compressive strength (CS), flexural strength (FS), water absorption (WA), abrasion resistance (Böhme's disk method), microstructure analysis (SEM), chemical composition (XRF), and crystal structure analysis (XRD). The results showed that the addition of fibers partially improved the mechanical properties of the geopolymers, as well as reducing microcracks. The CF-reinforced geopolymers exhibited the highest compressive strength, while the FF-reinforced geopolymers showed the lowest water absorption. The authors, based on previous research, also discussed the factors that influence fiber-matrix adhesion, and the optimal fiber content for geopolymers.

Dietary fibre profiling of various edible parts of winged bean (Psophocarpus tetragonolobus L.): Pods, whole seeds, endosperms, seed coats, and cooked seeds

This study aimed to identify the dietary fibre profiles of various winged bean components (green pods, whole seeds, endosperms, seed coats, and canned whole seeds). Soluble dietary fibre (SDF), insoluble dietary fibre (IDF) (hemicellulose, cellulose, and lignin), total dietary fibre (TDF), and oligosaccharide components (raffinose, stachyose, and verbascose), were analyzed. The various winged bean components had a higher IDF content than SDF content (21.12–50.11% and 0.83–1.25%, respectively), with the highest TDF content observed in the seed coat (51.81%). Raffinose was the most dominant oligosaccharide component in green pods (2.7 mg/g), while verbascose was the most dominant component in all seed form samples, including seed coats (1.41–3.65 mg/g). The IDF in all samples was dominated by cellulose (5.07–39.34%), followed by hemicellulose (1.5–27.19%), and lignin (0.09–0.98%). Seed dehusking led to significant decreases in all types of dietary fibre analyzed, except for stachyose. Soaking and sterilization processes resulted in an increase in SDF, but decreased IDF, stachyose, verbascose, and hemicellulose compared to raw whole seeds. Principal component analysis (PCA) revealed that raw whole seeds still exhibit similarities in dietary fibre composition with canned seeds, but differ from green pods, endosperms, and seed coats. These findings imply that all edible parts of winged beans offer a large quantity of dietary fibre, especially whole seeds, which have potential benefits as prebiotic sources to improve health.

The Use of Plastic Bottle Fibers in the Geotechnical Improvement of Tropical Soils from the Municipality of Viçosa - Brazil

Motivated by the environmental issues generated by the accumulation of waste from discarded plastic bottles and recognizing the utility of plastic properties in engineering, this research aimed to evaluate the application of plastic bottle fibers in the geotechnical improvement of tropical soils. In this context, the influence of quantity, roughness, and width of plastic bottle fibers on the shear strength parameters of soil- fiber mixtures, of two tropical residual soils, was analyzed. The fibers used in this study are made of Polyethylene Terephthalate (PET), generated from soft drink bottles, and added to the soil in different widths, textures, and contents. Results of the direct shear test showed higher shear strength for all soil-fiber systems compared to fiber-free mixtures. Additionally, the findings indicated that the systems with rough fibers presented better performances for clayey soil, whereas those with smooth fibers obtained better behavior for sandy soil. The cohesion results highlighted the better performance of mixtures with 0.5% fibers when compared to mixtures with 1% fibers. The enhancement of mechanical properties obtained in the studied soil-fiber systems demonstrates the potential application of these composites in geotechnical works.

Acoustic-Emission Criterion for Optimizing the Quantity of Fibers in the Concrete Matrix

Acoustic-Emission Criterion for Optimizing the Quantity of Fibers in the Concrete Matrix

Dynamic compressive behavior of steel fiber synergistically reinforced cellular concrete under high strain-rate loading

To better understand the reinforcement and toughness effects of steel fibers, a 75-mm split Hopkinson pressure bar (SHPB) device was used to test the uniaxial dynamic compression properties of steel fiber synergistically reinforced cellular concrete (SFSRCC) under high strain rates. The dynamic compression performance characteristics of the SFSRCC, including the stressstrain curve, dynamic strength, impact toughness and failure mode, were analyzed. The results showed that the dynamic strength, peak strain and impact toughness of SFSRCC increase with increasing strain rate. Compared with that of cellular concrete (SAP10S0), a higher steel fiber volume ratio corresponded to a greater enhancement in the dynamic performance characteristic indices of the SFRCC. The maximum increases were 138.4%, 180.0% and 280.0% for the DIF, peak strain, and impact toughness, respectively. The damage degree of the SFSRCC specimen decreased with increasing fiber content, and a larger area of residual "core retention" was observed, which indicated that the impact resistance of the SFSRCC with a high fiber content was improved. An empirical formula that can accurately characterize the dynamic strength increase factor (DIF) of SFSRCC with high strain rates was proposed, and the prediction results obtained by using the DIF of the SFSRCC were highly consistent with the test results, which confirmed its effectiveness. To further quantify the strain rate enhancement effect and fiber content for the reinforcement and toughening ability of SFSRCC, the relationships between the peak strength/peak strain/impact toughness and strain rate and between the DIF increment ratio/strain energy density increment ratio and fiber volume fraction were determined. In conclusion, the dynamic compression performance characteristics of SFSRCC can be enhanced by incorporating an appropriate quantity of steel fibers with a dynamic impact load.

Dietary Fiber in Inflammatory Bowel Disease: Are We Ready to Change the Paradigm?

Accumulating evidence from pre-clinical and clinical studies demonstrate the benefit of dietary fibers for inflammatory bowel disease (IBD). However, the majority of patients avoid or limit their consumption to manage their symptoms during the active and remission phases, although limited research supports these long-term dietary habits. Although recent evidence-based dietary guidelines highlight the importance of promoting an adequate intake of dietary fiber in IBD patients, intervention trials have not yet clearly clarified the quality and quantity of dietary fiber that should be consumed to be equally tolerated by and provide benefit for patients with IBD. This narrative review describes dietary fibers and their characteristics, analyzes the real-word studies on the impact of dietary fiber consumption in IBD in different clinical settings, and concludes with potential future directions in fiber research, focusing on the real-world needs of characterizing the consumption of fiber-rich foods and promoting their adequate intake.

Effect of Nylon Fiber Reinforcement on Mechanical Behavior of Expanded Perlite/Sodium Silicate Composites

In this research, expanded perlite/sodium silicate composites reinforced with nylon fibers were manufactured with varying percentages of nylon fibers without changing the quantity of expanded perlite and sodium silicate solution. The composites were made by compression molding and cured at a temperature of 120 degrees Celsius for 48 hours. The flexural and compression tests were conducted according to the ASTM standards in the universal testing machine. The maximum flexural and compressive properties are found for 1.62 percent nylon fiber reinforcement. The addition of a higher quantity of nylon fiber in the composites deteriorates the compressive and flexural properties. The energy absorption during flexural and compression tests is improved significantly due to nylon fiber reinforcement. The fiber-reinforced composites show the ability to carry a significant amount of load even after crack initiation.

A Review of Non-wood Lignocellulose Waste Material Reinforced Concrete for Light-weight Construction Applications

In recent decades, non-wood lignocellulosic materials have gained significant attention, particularly in concrete applications for construction purposes. This study delves into utilising non-wood lignocellulosic materials for reinforcing concrete in construction applications. Lignocellulosic material emerges as a promising option for formulating new fibre cement compositions, thereby enhancing the sustainability, affordability, and performance of construction materials. Moreover, this research broadens the horizons of recycling agricultural waste by facilitating rational disposal and optimal utilisation. Through a comprehensive review, the study reveals that flax fibres, coir pith, prickly pear fibres, and rice husk ash waste exhibit superior workability compared to their counterparts. Furthermore, the strength of non-wood lignocellulosic reinforced concrete, incorporating bagasse ash, rice husk ash, and nutshell ash, peaked when fine aggregate replacement reached 15%, surpassing other types of non-wood lignocellulosic reinforced concrete. Adding a small quantity of prickly pear fibre to cement enhances the thermal conductivity of concrete, consequently improving compressive strength, flexural strength, tensile strength, and elastic modulus. This research is relevant to international research as it advances sustainable construction materials with desirable properties, benefiting society and various industries.

The pioneer of intelligent and sustainable construction in tunnel shotcrete applications: a comprehensive experimental and numerical study on a self-sensing and self-heating green cement-based composite

In this study, a self-sensing and self-heating natural fibre-reinforced cementitious composite for the shotcrete technique was developed using Kenaf fibres. For this purpose, a series of Kenaf fibre concentrations were subjected to initial chemical treatment, followed by integration into the cement-based composite containing hybrid carbon nanotubes (CNT) and graphene nanoplatelets (GNP). The investigation encompassed an examination of mechanical, microstructural, sensing, and joule heating performances of the environmentally friendly shotcrete mixture, with subsequent comparisons drawn against a counterpart blend featuring a conventionally synthesized polypropylene (PP) fibre. Following the experimental phase, a comprehensive 3D nonlinear finite difference (3D NLFD) model of an urban twin road tunnel, completed with all relevant components, was meticulously formulated using the FLAC3D (fast lagrangian analysis of continua in 3 dimensions) code. This model was subjected to rigorous validation procedures. The performances of this green shotcrete mixture as the lining of the inner shell of the tunnel were assessed comparatively using this 3D numerical model under static and dynamic loading. The twin tunnel was subjected to a harmonic seismic load as a dynamic load with a duration of 15 s. The laboratory findings showed a reduction in the composite sensing and heating potentials in both cases of Kenaf and PP fibre reinforcement. Incorporating a specific quantity of fibre yields a substantial enhancement in both the mechanical characteristics and microstructural attributes of the composite. An analysis of digital image correlation demonstrated that Kenaf fibres were highly effective in controlling cracks in cement-based composites. Furthermore, based on the static and dynamic 3DNLFD analysis, this green cement-based composite demonstrated its potential for shotcrete applications as the lining of the inner shell of the tunnel. This study opens an appropriate perspective on the extensive and competent contribution of natural fibres for multifunctional sustainable, reliable and affordable cement-based composite developments for today’s world.

Finite Element Analysis of Polymeric Matrix Composites with Sisal Fiber Reinforcement

Recently, there has been a growing interest in investigating the mechanical properties of plant fibers, particularly in developing nations. This surge is primarily fueled by the escalating environmental concerns, which are becoming more evident and alarming. Against this backdrop, various sectors of materials engineering are actively seeking alternatives to mitigate the environmental impact across the entire lifecycle of products - from production to use and disposal. This study aims to conduct a computational analysis to examine the influence of fiber quantity on the tensile strength of composites containing sisal fibers. It compares the findings with existing experimental test results and demonstrates the outcomes using the finite element method. The research reveals that greater tensile strength in the composites is achieved with higher volumetric fractions of sisal fiber, as observed in both experimental and computational analyses. These results underscore a strong correlation between finite element analysis and experimental tests documented in the literature.

Effect of olive-pruning fibres as reinforcements of alkali-activated cements based on electric arc furnace slag and biomass bottom ash

In this work, alkali-activated composites using electric arc furnace slag (50 wt%) and biomass bottom ash (50 wt%) were manufactured, adding olive-pruning fibres as reinforcement. The objective of adding fibres is to improve the flexural strength of composites, as well as to prevent the expansion of cracks as a result of shrinkage. For this reason, composites reinforced with olive-pruning fibres (0.5–2 wt%) untreated and treated with three different solutions to improve matrix–fibre adhesion were manufactured. Treatments developed over fibres were a 10 wt% Na2SiO3 solution, 3 wt% CaCl2 solution and 5 wt% NaOH solution. Mechanical properties, physical properties, thermal properties and the microstructure of composites by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were studied to demonstrate the improvement. Alkaline treatment degraded fibre surface, increasing the matrix–fibre adhesion, and as a consequence, flexural strength increased up to 20% at 90 days of curing. Optimal results were obtained with composites reinforced with 1 wt% of olive-pruning fibre treated by a 10 wt% Na2SiO3 solution. Higher quantity of olive-pruning fibre leads to local agglomeration, which weakens the matrix–fibre adhesion. The effect on the compressive strength is less evident, since the addition of fibres produces an admissible decrease (between 0 and 9% using 0.5 or 1 wt% of fibres), except in composites that use olive pruning treated with 10 wt% Na2SiO3 solution, where values remain stable, similar or better to control paste. A greater ductility of the matrix in all composites was observed. Furthermore, the alkali-activated cement matrix was bonded to olive-pruning fibre better than untreated fibre, as it is shown in SEM images. Thus, the results showed that olive-pruning fibres could be used as reinforcement in the manufacturing of alkali-activated materials when they are treated with alkali solutions.

Experimental Study of Cast in Anchors Embedded in UHPFRC

This paper describes an experimental investigation of the behaviour of anchors precast in Ultra High-Performance Fiber-Reinforced Concrete (UHPFRC) under static loading. Initially, the current state of the art and related experimental studies are briefly mentioned. The next part of the paper is devoted to an experimental program aimed at describing the anchorage in cement composite UHPFRC in more detail. A total of 45 pull-out tests were performed. The tests investigated the effect of the fiber quantity in volume in the UHPFRC matrix (vf), the effective embedment depth of the anchor (hef) and the position of the anchor in the mould during concreting. Finally, the results are documented, the failure mode and the shape of the concrete cone, load-displacement curves and summary tables are presented. The paper concludes with a discussion of the results and further directions for solving the problem.

Influence of Recycled High-Density Polyethylene Fibers on the Mechanical and Electrochemical Properties of Reinforced Concrete

The quantity of different plastics generated after consumption is an impact factor affecting the environment, and the lack of recycling generates solid waste. The purpose of this work is to incorporate high-density recycled polyethylene fibers (HDPE) for possible use as concrete reinforcement. Physical and mechanical properties from recycled fibers were analyzed, such as density, absorption, and stress resistance, as well as workability, air content, porosity, concrete compression, and flexural strength properties. Samples were prepared with a low fiber content of 0.2% and 0.4%, as a substitution for sand weight, and lengths of 10 and 30 mm. To study corrosion phenomena, the specimens were exposed to a saline environment containing 3% sodium chloride for 365 days, and the electrochemical techniques including half-cell potential (HCP), electrochemical noise (EN), linear polarization resistance (LPR), and electrochemical impedance spectroscopy (EIS) were applied. The results showed a 4.8% increase in compressive strength with a low fiber percentage and short geometries, while flexural strength increased marginally by 2.3% with small quantities of HDPE fibers. All these factors contribute to greater material durability, less permeability, and crack control. A positive effect of fibers with short dimensions on the corrosion processes of a steel bar was observed, with the fibers acting as a physical barrier against the diffusion of chloride ions.

Changes in frontal aslant tract tractography in selected types of brain tumours.

To present differences in frontal aslant tract (FAT) tractography among patients diagnosed with primary brain tumours and metastatic brain tumours. The analysis included 38 patients diagnosed with a frontal brain tumour. A control group of 30 healthy patients was also considered. The FAT was delineated, taking into account ROI 1 - the superior frontal gyrus, and ROI 2 - SMA. Endpoints were determined on the pars opercularis and pars triangularis of the inferior frontal gyrus. FAT was delineated in four different ways for each patient. In the group of patients with a brain tumour, a lower volume of FAT and a reduced quantity of fibres were observed compared to the control group. Comparison of the examined parameters between patients with glioblastoma and metastasis revealed statistically significant differences for MD (p < 0.001) regardless of the selected projection. The difference in MD (mean diffusivity) among patients with metastatic tumours may be related to an increased oedema zone.

Sustainable reclamation of synthetic materials as automotive parts replacement: effects of environmental response on natural fiber vulnerabilities.

Sustaining the resilience of the environment against climate change volatilities is fast becoming a herculean task considering the vulnerabilities of the ecosystem and disruption of the global value chain. Environmental crisis emanating from improper containment of synthetic materials is a major impediment facing the world today, and the situation could get worse if urgent measures are not devised to mitigate the quantity of waste synthetic materials that find its ways to the environment. These wastes are released in the form of toxins, posing danger to the environments, causing biodiversity loss and the degradation of already battered-climate. In this paper, the authors apprise existing containment measures of synthetic waste materials taking a preliminary and on-the-spot assessment of their impacts and effectiveness of their application leading to their operation. The prospect of waste glass fiber in automotive part replacement is given utmost interest in this paper, in which, a significant quantity of glass fiber could be used as part of automotive materials to reduce their overbearing environmental carnage. By this approach, the emerging automotive parts may have their strength and durability enhanced against impact and corrosion. Mindful of the non-biodegradable properties of glass fibers, the paper captures how effective these fibers could be used as automotive parts against the traditional materials. This paper also reflects on the response of the natural fiber in terms of their sustainability, as natural forest faces severe extinction occasioned by anthropogenic activities.

A Feasible and Efficient Monitoring Method of Synthetic Fibers Released during Textile Washing

Microfibers (MFs) are one of the most common and hazardous forms of microplastic found in the aquatic environment. The methods of collecting and analyzing MFs released during washing have to be developed and standardized to understand and model the process of microfibers’ emission better. This study tests a new, innovative method to check if laundry fiber sampling can be approached comprehensively. Pieces of synthetic materials (aged and new polyester, polyester-cotton blend) were placed in chromium-nickel filters envelope-like folded. Then, textile weathering during washing was monitored by the quality and quantity of fibers found directly on the filter surface. Laundry parameters like temperature, detergent presence, and filter size were changed, and results were monitored by Fourier-transform infrared spectroscopy (FTIR), a well-known standard in microplastic identification. In addition, ATR spectra were collected to characterize the materials in detail and evaluate their aging level. Spectroscopy can be used to detect and examine both mechanical and chemical degradation, and the collected microfibers can be assigned to the material they come from. Finally, a quantitative comparison of fibers released during different washing conditions can be used for the process optimization to minimize its environmental impact.