Waste Fibers Research Articles

Investigation of the Rheological Characteristics of Asphalt Modified from Medical Mask Waste Fibers

Masks are essential for preventing people from breathing in dangerous compounds and airborne pollutants. On the other hand, incorrect mask disposal presents a serious environmental risk. Medical masks are mostly made of polypropylene and are formed of three layers: a central layer of melt-blown material, an outer layer of waterproof non-woven fabric, and an interior layer. This research aims to determine the effect of medical mask waste fiber on the rheological characteristics of asphalt. In terms of the rheological characteristics of asphalt, the addition of asphalt will decrease the penetration, ductility, specific gravity, and lost on heating, and increase the viscosity, softening point, and flash point. The positive impact is that the inclusion of mask waste results in increased asphalt hardness, enhancing resistance to rutting. On the other hand, the negative impact is that the inclusion of masking waste will reduce the resistance to cracking due to the reduced elasticity.

Investigating interphase bond behavior of waste badminton string fiber in composite matrix

ABSTRACT Recently moving towards the usage of sustainable and renewable construction materials, the badminton strings are identified as alternate material for commercial fibers. These recycled badminton strings once discarded from the racquets become a waste and cannot be reused. Hence investigation of the interphase bond behavior of these fibers with the cement and epoxy polymer matrix plays a major role. Therefore, the pullout mechanism between the fibers with the epoxy matrix is examined using the photoelasticity technique with a 40 mm embedment length. Whereas the pullout mechanism between the fibers with the cementitious matrix is examined for a single string of fiber using a pullout test with varied embedment lengths of 10, 20, 30, 40, 50, 60, 70, and 80 mm. From the study, the minimum and maximum bond stress between the fiber and epoxy interface is 3.23 MPa and 11.59 MPa respectively. Whereas between the fiber and cementitious interface, the minimum and maximum bond stress is 1.02 MPa and 2.15 MPa respectively. The experimental results are validated by the Weibull modulus approach which shows less variability. Thus, the results of the pullout test in composite matrix recommend the usage of waste badminton strings in fiber-reinforced concrete applications.

Advancements in precast concrete sandwich panels for load bearing structures

Concrete sandwich panels consist of two concrete layers separated by an insulating foam core, offering thermal insulation, structural strength, and fire resistance. This study investigates sustainable precast concrete sandwich panels made with industrial waste materials like limestone slurry, quarry waste, and basalt fiber as shear connectors. The research evaluates the flexural and axial strength behavior of these panels and explores strategies to improve their structural performance. The panels were fabricated with outer concrete layers, an expanded polystyrene (EPS) insulation core, and basalt fiber connectors. Flexural tests using four-point bending and axial compression tests were conducted on panels with varying concrete layer thicknesses and basalt fiber widths. Findings revealed panels with thicker outer concrete layers (35mm) and wider basalt fiber connectors (11.5mm) exhibited higher cracking loads, load-hardening behavior, and increased ductility compared to thinner layers and narrower connectors. The axial test showed premature failure at the top and bottom quarters. Thicker concrete layers and wider basalt fiber connectors enhanced crack control, load distribution, and ductile behavior under flexural loading. Strengthening measures like additional reinforcement, proper anchorage detailing, and increased shear reinforcement at the end regions are recommended to improve axial load-bearing capacity and prevent premature end failures. The PCSP demonstrated up to 40% cost savings over commercial products while providing better thermal insulation than conventional brick masonry due to the EPS core. Overall, the study promotes developing sustainable, energy-efficient, and cost-effective load-bearing sandwich panel systems.

Cellulose-Based Waste in a Close Loop as an Adsorbent for Removing Dyes from Textile Industry Wastewater

In an attempt to reuse fibrous textile waste and, at the same time, to address dye pollution in textile wastewater, waste cotton-based yarn was utilized as a cheap and sustainable adsorbent, as well as a row material for carbon adsorbent production. Unmodified yarn and cotton-based carbon adsorbents were used as adsorbents for dye removal from water. Cotton and cotton/polyester yarn samples underwent thermal modification through carbonization followed by chemical activation with KOH. Various techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, nitrogen adsorption–desorption isotherms, and surface charge determination, were employed to analyze the morphological and surface characteristics of the cotton-based adsorbents. Adsorption properties were evaluated by testing the removal of selected cationic and anionic dyes from water. The impact of temperature, initial pH and concentration of the dye solution, and contact time on adsorption were investigated, and experimentally obtained data were analyzed using theoretical models. While carbonization alone did not significantly enhance adsorption properties, activated samples exhibited high efficacy in removing both cationic and anionic dyes from water. Despite the negative influence of the polyester component in the carbon precursor on the efficiency of activated samples in removing methyl orange, the results indicated that activated cotton and cotton/polyester yarn could be used to prepare highly efficient adsorbents for the rapid removal of methylene blue from real wastewater samples.

Fire safe and sustainable lightweight materials based on Layer-by-Layer coated keratin fibers from tannery wastes

The increasing consciousness about the depletion of natural resources and the sustainability agenda are the major driving forces to try to reuse and recycle organic materials such as agri-food and industrial wastes. In this context, keratin fibers, as a waste from the tannery industry, represent a great opportunity for the development of green functional materials. In this paper, keratin fibers were surface functionalized using the Layer-by-Layer (LbL) deposition technique and then freeze-dried in order to obtain a lightweight, fire-resistant, and sustainable material. The LbL coating, made with chitosan and carboxymethylated cellulose nanofibers, is fundamental in enabling the formation of a self-sustained structure after freeze-drying. The prepared porous fiber networks (density 100 kg m–3) display a keratin fiber content greater than 95 wt% and can easily self-extinguish the flame during a flammability test in a vertical configuration. In addition, during forced combustion tests (50 kW m–2) the samples exhibited a reduction of 37 % in heat release rate and a reduction of 75 % in smoke production if compared with a commercial polyurethane foam. The results obtained represent an excellent opportunity for the development of fire-safe sustainable materials based on fiber wastes.

Influence of Alkali Treatment on Bamboo/Coconut Husk Hybrid Fibre Polyester Composite

This research addresses the importance of hybrid composites in material science, specifically, demonstrating the effective reinforcement of unsaturated polyester with bamboo and coconut husk fibre through alkali treatment. The primary problem this work aims to solve is the improvement of the mechanical properties of unsaturated polyester by combining it with bamboo and coconut husk fibres which contain both lignocellulosic and cellulose fibres. Alkali treatment, particularly, sodium hydroxide (NaOH) solution, was used in this study due to its cost-effective nature and its ability to enhance the strength of both individual fibres and resulting composite. The effect of NaOH treatment with concentrations ranging from 2 – 10 wt.% on dried hybrid fibres was investigated. Chemically treated fibre composites were discovered to have improved mechanical characteristics as both tensile tests and thermogravimetric analysis (TGA) showed higher strength and thermal stability after being treated. Notably, findings identified an optimal content of 8 wt.% NaOH solution for surface modification, showcasing the potential for using NaOH-treated waste fibres to reinforce polyester resin. The implications of this study extend to a promising avenue for enhancing the performance and application of natural fibre-reinforced composites. The insights provided here offer a foundation for advancing the utilization of hybrid composites.

Design, Cultivation, and Acoustic Analysis of a Building-Sized Mycelium Sculpture

Abstract This paper describes novel computational design, simulation, and fabrication techniques employed in the production of a large sound-absorbing sculpture called Phoenix, made entirely from mycelium-composite materials (myco-materials). Myco-materials are composites made of lignocellulosic agricultural waste fibers bound by fungal mycelium and are produced at commercial scale as alternatives for plastics, insulation foam, or styrene. Mycelium composite materials have known acoustical properties that can be tuned according to variables such as growing time, substrate type, substrate size, and density. The fabrication method for producing the Phoenix sculpture revisits how we build performative and formal complexity in the most economic and sustainable way. The results indicate the potential for grown materials to be used in retrofit projects, allowing rooms to be customized in various acoustical situations, such as music or speech.

The Thermo-Phase Change Reactivity of Textile and Cardboard Fibres in Varied Concrete Composites

The building and construction industry heavily relies on the use of concrete and cementitious composites due to their exceptional attributes, including strength and durability. However, the extensive use of these materials has led to significant environmental challenges, including resource depletion, carbon emissions, and waste accumulation. In response to these challenges, recent advancements in fibre cementitious composites have shown promise in mitigating these detrimental effects. The integration of waste materials to supplement manufactured fibres represents a promising development in reinforced concrete composite materials. Waste materials like textiles and cardboard are emerging as potential fibre supplements in cementitious composites. While these materials have primarily been investigated for their mechanical characteristics, understanding their thermal properties when applied in construction materials is equally crucial. Incorporating fibres within composite designs often requires matrix modification to reduce degradation and enhance fibre longevity. This study aims to investigate the thermo-phase change properties of both textile and cardboard fibres within varied concrete matrices. Additive materials offer a range of advantages and challenges when used in composite materials, with additional complexities arising when incorporating fibre materials. Understanding the thermal reactivity of these materials is crucial for optimizing their application in construction. This study demonstrates the potential of waste fibres used with gypsum, metakaolin, and silica fume as matrix modifiers in concrete. This research provides valuable insights for future studies to explore specific material combinations and investigate complex fire testing methods, ultimately contributing to the development of sustainable construction materials.

Utilizing Waste Cotton/Pigeon Pea Stalk Fibers Composites for Enhanced Sound Absorption and Insulation in Automotive Interiors

ABSTRACT This study investigates the synthesis and characterization of composite materials, pigeon pea stem, and cotton fibers blended in different ratios such as 100/0, 70/30, 60/40, 50/50, 30/70, and 0/100. These composite materials were produced using a compression molding technique. According to ASTM standards, the acoustics, thermal conductivity, and physical characteristics of the composite samples were tested to assess their qualities. The impedance tube method detailed in ASTM E1050 was used to determine the sound absorption coefficients (SAC) for acoustics. The SAC values were measured at six frequencies such as 125, 250, 500, 1000, 2000, and 4000 Hz. The results showed that composite samples made from waste cotton and pigeon pea demonstrated sound absorption values of greater than 80%. Superior sound insulation and absorption, moisture absorption, fiber properties have also been demonstrated by waste composites. Especially, the waste cotton/pea stalk waste fiber composites achieved over 75% sound absorption, while the waste 28% composites performed well in terms of sound absorption, moisture absorption, and fiber properties. Even in humid conditions, the composite samples constructed from used cotton and pigeon pea stalks demonstrated good moisture resistance without reducing their insulating qualities. Soundproofing barriers are composite layers of foam or pigeon pea/cotton.

Electrically conductive cementitious composites for marine applications

Conductive cement-based materials have attracted particular attention due to their potential to enable low-cost continuous monitoring of next-generation smart structures. This feature is relevant in highly energetic marine environments, where structural damage due to excessive loads and remote locations are critical to the performance of structures. However, to the best of the authors knowledge the literature exploring this feature in the context of marine environment is inexistent. To fill this gap, an electrically conductive cementitious composite (E3C) was developed for marine applications by introducing waste materials and fibers. Six mixtures were studied, incorporating the same matrix but varying the amount and fiber type, and water content. E3C, which conducts electricity underwater, was successfully developed, demonstrating the capacity to exhibit intelligent properties in marine environments. Self-sensing capability, assessed through electric current measurements during load application, demonstrated sensitivity to mechanical loading. This research presents promising outcomes, reshaping the paradigm of marine structures.

Performance evaluation of stone mastic asphalt reinforced with shredded waste E-cigarette butts

The recycling of waste materials in asphalt pavements is pivotal for advancing the road industry, offering numerous environmental, economic, and societal benefits. This study explores the recycling potential of waste electronic cigarette butts (E-CBs) within stone mastic asphalt (SMA) mixtures, serving as a substitute for cellulose fibres and enhancing mechanical performance. Considering the critical role of fibre size in asphalt mixtures, two different E-CB shredding sizes (10 and 15 mm) were selected for examination. Additionally, the influence of the plastic component within E-CBs was investigated. The stabilizing effects of using the shredded E-CBs were evaluated via drain-down tests, followed by a series of standard laboratory tests aimed at assessing physical and mechanical properties. Results demonstrate acceptable drain-down properties, volumetric properties, and moisture susceptibility for the use of all four shredded E-CBs. Among the four mixtures incorporating the waste fibres, the utilization of 15 mm shredded E-CBs without plastic constituents yielded the highest values for indirect tensile strength (ITS) and indirect tensile stiffness modulus (ITSM), coupled with excellent water susceptibility and rutting performance. It can be considered a promising alternative to the traditional cellulose fibre. Larger shredded E-CBs exhibited potential for improving mechanical properties, encompassing cohesion, stiffness modulus, and rutting resistance. Although plastic inclusion can enhance rutting resistance, the higher thermal susceptibility associated with plastic warrants careful consideration. Future research may focus on investigating the fatigue and low-temperature cracking properties, as well as the reinforcing mechanisms of shredded E-CBs in asphalt mixtures using micro-characterization techniques.

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.

Fly Ash and Fiber Waste As Principal Geopolymer Mortar Material: A Review

Geopolymer mortar is an innovative mortar using fly ash waste as an alternative to cement. The development of advanced fiber geopolymer mortar materials is an alternative solution to the weaknesses and shortcomings of conventional materials so that they have the ability to reduce and even absorb sound intensity and prevent noise propagation in overcoming noise problems in the field of building construction. Many factors can affect sound absorption, including the type of aggregate, modification of material composition that has a density level in fiber geopolymer mortar. The development of fiber geopolymer mortar can be developed in the construction field to reduce sound frequency and improve sound insulation. There are also different measurement mechanisms to determine the performance of the material in improving sound quality. This paper aims to review the performance of sound-absorbing fiber geopolymer mortar. This review is expected to provide insight into the development of fiber geopolymer mortar in building construction to improve comfort and reduce noise pollution.

The Effect of Adding Coconut Coir Fiber on Compressive Strength, Tensile Strength, and Concrete Flexural Strength in Eco-Friendly Tetrapod Planning in Coastal Areas of IKN Supporting Cities

Beaches often experience erosion or abrasion problems caused by various factors, such as climate change which triggers rising sea levels, high waves, human activities such as beach reclamation, and infrastructure construction that is not environmentally friendly, triggering erosion on the coast. In the coastal area of the city that supports IKN, which is located in the Balikpapan area, Manggar Beach, also experiences abrasion which causes land to narrow in that area. The abrasion that occurs erodes the coastal area around 7-8 meters every year. To produce environmentally friendly infrastructure, this research carried out the addition of coconut fiber waste components to tetrapod concrete used for breakwater construction. In this research, variations in the addition of coir used were 0%, 1%, 2%, 3%, 4% and 5%. The aim was to find out how much influence the addition of coconut coir waste to the concrete mixture had on the compressive strength, tensile strength and flexural strength of the concrete in tetrapods. and produce concrete that uses coconut fiber waste as an alternative material for tetrapod concrete as breakwater armor. Based on the analysis results, the quality of the concrete was 23 Mpa. This value was determined based on wave generation analysis. In addition, it is known that variations in coconut fiber affect the slump, compressive strength, flexural and split tensile test values of concrete. Based on the slump test results, it was found that the greater the variation of coconut fiber in the concrete, the lower the resulting slump test value. In testing the compressive, flexural and split tensile strength, it was found that the optimal composition for adding coconut fiber was 3%, in this composition the amount of coconut fiber fiber was able to improve the mechanical properties of tetrapod concrete compared to other compositions.

Optimization of date palm waste fiber content and length in sand concrete using the factorial design approach

The valorization of some agri-food industry by-products, particularly plant waste, in a number of countries may be significantly interesting in the field of civil engineering because they can be used to prepare low-cost biomaterials that consume low amounts of energy and are environmentally friendly. Recently, it has been revealed that the valorization of date palm fibers (DPFs) waste and incorporating them into concrete may be one of the promising solutions that can be adopted in order to reduce or eliminate the huge amounts of this type of waste from our environment and to improve the properties of concrete. The present work aims primarily to investigate the effect of incorporating date palm waste fibers into sand concrete on the properties of this concrete in the fresh and hardened states. For this, two DPF contents were considered. First, 0.1% of DPFs with lengths 2cm and 6cm, and second 0.2%of DPFs with lengths 2cm and 6cm. Furthermore, a factorial design was used for the purpose of analyzing the influence of varying these two parameters, i.e. fiber content and fiber length, on the physico-mechanical properties of the sand concrete produced. In addition, it should be noted that the response to be considered in this design is the compressive and flexural strengths. Moreover, the JMP statistical software was utilized for analyzing the interactions observed and examining the responses that is predicted by the model generated using the factorial design. The findings showed that the expected responses obtained from the adopted model are in good agreement with the experimental data. Further, it was found that the fiber length factor has a positive effect on the response (strength). However, increasing the DPF content in the formulation of sand concrete has a negative effect on his compressive strength.

The Growing Problem of Textile Waste Generation—The Current State of Textile Waste Management

The textile industry is global, and most brands export their products to many different markets with different infrastructures, logistics, and regulations. A textile waste recovery system that works in one country may fail in another. European Union legislation (Directive (EU) 2018/851) mandates that post-consumer textile waste must be separately collected in all associated countries. This directive has also stated that, in January 2025, the rate of textile waste recycling in Europe should be increased. Local governments will be under pressure to improve the collection, sorting, and recycling of textiles. Supporting local governments could be part of a more long-term approach to managing high-value textile waste by implementing Extended Producer Responsibility, which would increase the recycling rate of textile companies. This would enable reuse of over 60% of recovered clothes, recycling into fibers of 35%, and only throwing away 5%. Today, most textile waste (85%) is disposed of as solid waste and must be disposed of through municipal or local waste management systems that either landfill or incinerate the waste. To increase reuse and recycling efficiency, textile waste should be collected and sorted according to the relevant input requirements. The dominant form of textile waste sorting is manual sorting. Sorting centers could be a future solution for intensifying the recycling of textile waste. Advances in textile waste management will require digitization processes, which will facilitate the collection, sorting, and recycling of textiles. It is very important that digitization will help to guide used products to recycling and encourage manufacturers to participate in the use and collection of product data. Currently, both the digitization of textile waste management and fiber recycling technologies are at the level of laboratory research and have not been implemented. The aim of this publication is to analyze the state of textile waste management, especially the various forms of recycling that involve a local governments and the textile industry.

Micromechanical Modelling of the Deformation Mechanisms of Friction-Spun Yarn from Recycled Carbon Fibres

The growing use of carbon fibre-reinforced polymers (CFRP) results in an increased amount of CF waste from offcuts or end-of-life components. A promising method to reuse the waste fibre materials in a structural component with excellent mechanical properties is the processing of recycled CF (rCF) and thermoplastic fibres into hybrid yarns. Spinning of friction spun yarns consisting of more than 90% rCF and containing almost no thermoplastic fibres that are suitable for thermoset composites, currently leads to high fibre damage and low yarn quality and is, therefore, addressed in this project. The technology is reported in another paper. One of the limiting factors for drapability of textiles is the stretchability of continuous fibres and draping of the semi-finished textile products for complex geometries is still error-prone. Friction spun yarns exhibit significantly higher yarn elongations due to sliding mechanisms between the fibres. The deformation properties of friction spun yarns are significantly influenced by fibre-fibre interactions and depend on a variety of process and material parameters. In the following, micromechanical finite element models of the spun yarns are created by using beam elements. Monte Carlo method is used to model local variabilities in the yarns. The models are then used to simulate yarn behaviour under deformation and to investigate the influence of various process parameters.

Sustainable design and carbon-credited application framework of recycled steel fibre reinforced concrete

Waste tires pose significant environmental, health, and fire risks. Creative waste management solutions, including reuse, recycle and repurpose, are necessary to mitigate those impacts while enriching their valorisation. An innovative solution is the upcycling of recycled steel fibre (RSF) from waste tires to enhance strength and durability of concrete. This study thus experimentally examines dynamic and mechanical behaviours of high-strength concrete with varying proportions of RSF, from 0% to 1.2% by volume. The results reveal that high-strength concrete with 1.2% RSF exhibits the best improvement in strengths. In addition, the damping ratio, dynamic modulus of RSF concrete and SEM images confirm valorisation potentials of waste fibres. Via a robust critical lifecycle analysis, the new insights form a new sustainable design and carbon credited application framework for RSF. Our results portray that innovative recycling practices for end-of-life tires yield substantial environmental benefits, including a significant carbon emission reduction.

Impact of treated red-algae fibers on physico-mechanical behavior of compressed earth bricks for construction

Red algae, abundant along the Moroccan coast, have fostered an agar-agar industry. However, industrial processing of red algae produces significant fibrous waste, posing environmental challenges. A new challenge is to find sustainable methods for repurposing this fibrous waste. Valorizing red-algae fibers in building materials promotes sustainable development and eco-construction. This study aims to valorize these red-algae residues as fiber reinforcements in compressed earth bricks (CEB). Various mass ratios of red-algae fibers (0.5%–3%) were incorporated into CEB. The addition of raw red-algae fibers to mixtures slightly increased the Atterberg limit values of the earth mixture. A slight adjustment in manufacturing water content was also observed with fiber addition. The incorporation of red-algae fibers did not improve the mechanical strengths of the CEB. Nevertheless, at a 1.5% addition ratio, CEB exhibited compressive and flexural strengths of 4.07 and 0.77 MPa respectively. To enhance mechanical properties, fibers were pre-saturated and subjected to alkaline and double coating treatments. Untreated and treated fibers were added to CEB at an optimal mass addition rate of 1.5%. Pre-saturated fibers showed a slight improvement of 5% in mechanical strength. However, alkali-treated and double-coated fibers offer a significant improvement of 20% in the mechanical strengths of CEB, demonstrating the efficacy of treatments.

Physicochemical properties of oil palm biomass waste fibres and its cellulose for engineering applications: a review

Physicochemical properties of oil palm biomass waste fibres and its cellulose for engineering applications: a review