Fiber Cement Composites Research Articles

The Compatibility of Cement Bonded Fibreboard Through Dimensional Stability Analysis: A Review

Natural fibre in cement matrix was used to reinforce, increase tensile strength, and protect against matrix cracking. The various properties of the matrix, which were introduced by the shrinkage and thermal stresses, can be attributed to the microcracks on the composites. The composites experienced significant negative changes due to the spread of microcracks. Changes in moisture have an impact on the dimensional stability of cement-bonded fibreboards. The increasing moisture content caused the expansion of cement-bonded fibreboard, whereas shrinkage was caused by the moisture being evaporated. Since natural fibres connect ineffectively with the cement matrix due to their hydrophilicity, fibre-cement composites are dimensionally unstable. Hot water treatments operate by clearing the fibre’s surface of volatile compounds, impurities, and waxy elements and facilitating water absorption. Numerous variables, including the mixing ratio, the targeted density, and the pre-treatment technique used on natural fibre, influence the dimensional stability of cement-bonded fibreboard. The compatibility of cement-bonded fibreboard increases with increasing cement/fibre mixing ratio, density of cement-bonded fibreboard, hot water treatment temperature and duration.

Effect of Graphene Oxide on the Electrothermal and Pressure-Sensitive Properties of Carbon Fiber Cementitious Composites.

The application of carbon fiber in cement matrix has some disadvantages, such as poor dispersion and poor interfacial adhesion. In order to improve the interaction between carbon fiber and cement matrix and improve the properties of cement-based composites, carbon fiber was modified by electrophoretic deposition of nano-graphene oxide (GO). In this paper, the effects of doping CF into the cement matrix before and after GO modification are studied comparatively in terms of electrical conductivity, electrothermal warming effect, and pressure-sensitive properties of the cement matrix. It was found that the GO-modified CF reduces both the electrical resistivity of cementitious composites and the required level of fiber incorporation compared to CF. The percolation threshold is 0.7 wt% for CF and 0.5 wt% for GO-CF. The GO-modified CF is more effective than CF as a conductive filler to enhance the electrothermal warming performance of the cement matrix. When the GO-CF doping rate is 0.5%, the specimen temperature increases most rapidly, and the temperature rise value reaches a maximum of up to 30.45 °C, which is twice that of the CF group. When the fiber content is 0.7%, the pressure sensitivity of the sample was the best. When the fiber content is 0.5%, GO-CF can improve the pressure sensitivity of cement mortar specimens, and increase the resistance change rate of the cement mortar specimens by 5.7%.

Mechanical performance study of PVA fiber-reinforced seawater and sea sand cement-based composite materials

Due to the swift progress in the construction sector, there is a global concern about the potential scarcity of river sand and freshwater resources. The development of new construction materials is considered an inevitable trend for industry growth. PVA fibers, known for their strong corrosion resistance, cost-effectiveness, and high toughness, have the potential to enhance the corrosion resistance and seismic performance of structures in marine environments. However, their mechanical properties and durability in the seawater and sea sand environment are not well understood. Therefore, the investigation of the impact of seawater and sea sand on the mechanical properties and durability of PVA fiber-reinforced cement composites is considered crucial. A mechanical performance analysis of PVA fiber-reinforced seawater and sea sand fiber cement composites was conducted in this study. PVA fiber volume fractions of 0%, 0.75%, and 1.5%, cement composite matrix strength grades of C30 and C50, and curing periods of 28 days, 90 days, and 180 days were examined, investigating their influence on the bending toughness of PVA fiber-reinforced seawater and sea sand cement composites. Specific conclusions include the addition of fibers increased the peak bending load, had a less corrosive effect in seawater, and improved the flexural toughness of the material. The most significant improvement was observed at 1.5% fiber content, where the load-deflection curve was fuller and the energy absorption capacity of the material increased by 33–109%, maintaining good bending toughness. Furthermore, higher fiber contents are required for high-strength cementitious composites to improve flexural toughness and durability. The formulation of calculation formulas for predicting bending strength and corresponding deflection, which fit well with the experimental results; and the development of a calculation model for the bending toughness index of PVA fiber-reinforced seawater and sea sand cement composites, providing an effective prediction of material bending toughness.

A feasibility study of oil palm empty fruit bunch pulp as a substitution for radiata pine pulp for autoclave fibre cement composite production

The main objective of this study was to investigate the feasibility of using unbleached pulp from oil palm empty fruit bunches, produced via the Ethanolamine pulping process, to replace Radiata Pine pulp in autoclave fibre cement composite (AFCC) manufacturing. The Ethanolamine pulping process was chosen for its silica retention capability on empty fruit bunch surfaces. The research involves three key phases: an initial characterization of RPP and EFBP properties, including kappa numbers and pulp aspect ratios; subsequent AFCC production with varying RPP content levels (0%–13%) and different cement-to-silica (C/S) ratios (0.2–1.0); and the introduction of EFBP as a partial or complete substitute for RPP at a fixed C/S ratio. Results reveal RPP excels in fibre quality attributes like length, coarseness, fineness, width, and wet/dry zero span, while EFBP offers advantages in fibre count and macro fibrillation index. X-ray diffraction confirms silica presence on EFBP. The highest modulus of rupture (MOR), at 15.5 MPa, is achieved with 9% RPP and a C/S ratio of 1.0. Subsequent analysis, with 1% EFBP interval substitutions to total 13% pulp content, yields the highest MOR values under dry (16.7 MPa) and wet (9.9 MPa) conditions using recipes with 6% RPP and 3% EFBP. XRD confirms the presence of silica on EFBP, forming a crystalline flake layer post-autoclaving. Thus, EFBP proves suitable as a partial AFCC substitute.

Impact of mineralization in Hevea brasiliensis fibers on the production of extruded fiber-cements with cellulosic micro/nanofibrils (MFC/NFC) and quartzite residues

New processes and applications for waste generated in forestry and mineral activities favor the circular economy and reduce pressure on conventional raw materials, thus promoting the sustainability of activities. This research aimed to apply quartzite powder to replace limestone and fibers and cellulosic micro/nanofibrils (MFC/NFC) from Hevea brasiliensis as reinforcement in extruded fiber-cement. To improve fiber/matrix compatibility, some fiber treatments with NaOH and Aℓ2(SO4)3 + C6H8O7 were also evaluated. The fiber cements were produced by an extrusion process using a formulation of 66.5 % of CPV-ARI Portland cement, 28.5 % of quartzite powder and 5 % of fiber reinforcement. The physical (apparent density, water absorption, and porosity), mechanical properties (modulus of rupture, modulus of elasticity, limit of proportionality, and toughness), thermal conductivity, and microstructural properties of the fiber-cements were evaluated after 28 days of curing. Treatments with 5 % fibers exhibited better mechanical performances. It was possible to improve the microstructure and physical-mechanical performance of the composites using small amounts of MFC/NFC (0.5 %). Quartzite positively affected the properties and provided thermal comfort (∼0.11 W/mK). Therefore, the materials showed promise for producing extruded fiber-cement composites.

Innovative utilization of agro-industrial by-products: Bamboo leaf ash as a pozzolanic material for extruded fiber cement composites

This study aims to promote the valorization of agro-industrial waste and sustainability in the construction industry by evaluating the potential of bamboo leaf ash (BLA) as a partial replacement for Portland cement in extruded fiber cement. Squeeze flow, physical, mechanical, and microstructural analyses (Scanning Electron Microscopy and X-ray microtomography) were conducted. The results showed that the incorporation of fibers and BLA leads to an increased water demand and, consequently, an increase in porosity and pore connectivity. However, the mix design with 10 % replacement exhibited improved mechanical behavior for modulus of rupture (10.2 %) and limit of proportionality (4.5 %), when compared to a formulation without BLA. For the other parameters, the mix design with 10 % BLA showed mechanical behavior with no statical difference to the mix design without ash. Thus, the use of BLA as a partial replacement for Portland cement represents an alternative with technical and environmental improvements for fiber cement.

Effect of Adding Oil Palm (Elaeis guineensis Jacq.) Mesocarp Fibers to Cement Composites

The construction industry's ongoing pursuit of eco-friendly materials has led to extensive research into fiber cement composites (FCC), particularly those utilizing natural fibers such as oil palm (Elaeis guineensis Jacq.) mesocarp fiber (OPMF) from Peru. This study examined the physical, mechanical, and chemical effects of adding different proportions of OPMF (0, 3, 6, and 9%) in manufacturing FCCs. This addition resulted in reduced values regarding density, porosity, and modulus of rupture, as well as in increased moisture content and thickness reduction. The FCC containing 3% OPMF exhibited the most favorable performance thanks to its higher density and its lower water absorption and porosity when compared to the control board (0%-OPMF). Micro-images revealed minor microcracks and interfacial gaps, indicative of debonding, which compromises the properties of the FCC. Furthermore, an infrared spectrum analysis demonstrated an increase in hydroxyl group vibrations with an increased fiber proportion.

Comparative performance of M-S-H cement vs. portland cement in fiber cement incorporating bamboo leaf ash and cellulosic fibers

This study evaluates the potential of alternative materials such as Hydrated Magnesium Silicate (M-S-H) cement, bamboo leaf ash (BLAsh), and cellulose fibers to enhance the sustainability and performance of fiber cement composites. Innovative in its approach, the research incorporates BLAsh and cellulose fibers into M-S-H and Portland cement (OPC) matrices using an innovative production process: extrusion. For the characterization of different formulations, a comparative analysis was conducted on samples with M-S-H and Portland cement matrices, with BLAsh replacing limestone and the addition of unbleached pine cellulose fibers. The analysis covered the physical, mechanical, and microstructural properties of the composites. After a 7-day curing period, they were subjected to 200 cycles of accelerated aging to evaluate durability. Microstructural analysis revealed the binding potential of the M-S-H matrix used in this study due to the pronounced formation of M-S-H gel and reduced content of Mg(OH)2 over time. The formation of C–S–H and M-S-H gel as the main phase for each type of cement is even more evident in samples incorporating BLAsh, indicating the interaction between both types of matrices and bamboo leaf ash. The study demonstrated that adding BLAsh to the composites significantly improved the modulus of rupture of the OPC samples (approximately 32 %), while considerably reducing water absorption for the M-S-H samples (around 50 %). Aging affected water absorption differently in OPC and M-S-H samples, with OPC showing decreased absorption and the M-S-H showing increased absorption post-aging. The study proved both types of cement suitable for producing composites that meet NBR 15498 standards for external applications. This demonstrates the technical feasibility of these compounds for their production by 3D printing.

Effect of Hybridization of Carbon Fibers on Mechanical Properties of Cellulose Fiber–Cement Composites: A Response Surface Methodology Study

Fiber-reinforced cement composites, particularly those incorporating natural fibers like cellulose, have gained attention for their potential towards more sustainable construction. However, natural fibers present inherent deficiencies in mechanical properties and can benefit from hybridization with carbon fibers. This study focuses on the incorporation of cellulose and carbon fibers, in varying contents, into fibrocement composites, employing a Response Surface Methodology (RSM) to optimize the material characteristics. The methodology involves testing, encompassing flexural tensile, compression, and fracture toughness tests. The results indicate an increasing trend in flexural strength for higher carbon fiber content, peaking near 5%. A plateau in flexural strength is observed between 1.2% and 3.6% carbon fiber content, suggesting a range where mechanical properties stabilize. Compressive strength shows a plateau between 1.2 and 3.6% and reaches its highest value (≈33 MPa) at a carbon fiber content greater than 4.8%, and fracture toughness above 320 MPa·m1/2 is achieved with carbon fiber content above 3.6%. This study offers insights into optimizing the synergistic effects of cellulose and carbon fibers in fibrocement composites.

Enhancement of Flexural Strength in Fiber–Cement Composites through Modification of Sisal Fiber with Natural Rubber Latex and Expanded Perlite

This study presents a novel approach in enhancing the flexural strength of sisal fiber cement composites by employing a dual coating technique with natural rubber latex and expanded perlite to the sisal fibers. The effects of different fiber content (0.25, 0.5, 0.75, 1, 1.25, and 1.5 wt%) and fiber length (1, 2, and 3 cm) on the physical and mechanical properties of sisal fiber cement were also studied. The physical properties, including bulk density and water absorption, were evaluated via the Archimedes method. Flexural strength was measured using the 3-point bending method, and microstructure was observed using a scanning electron microscope (SEM) and an optical microscope (OM). As the fiber content and length increase, the bulk density of the sisal fiber cement decreases. However, composites utilizing coated fibers consistently exhibit a higher bulk density than those utilizing uncoated fibers, attributed to enhanced adhesion and reduced porosity. The water absorption of sisal fiber cement increases with fiber content, but it is mitigated by the natural rubber latex coating, which prevents fiber–water absorption, and by expanded perlite, which reduces voids in the matrix. Composites containing coated fibers consistently exhibit superior flexural strength compared to those with uncoated fibers. The highest flexural strength values of 5.58 MPa were observed in composites utilizing 3 cm of coated fiber with 0.25 wt% fiber content. Microstructure analysis reveals a well-bonded interface in coated fibers, emphasizing the positive impact of coating on mechanical performance. The incorporation of coated sisal fibers effectively improves adhesion, water resistance, and flexural strength, offering sustainable and durable construction materials. The achieved results can serve as the guidelines for the development of a high-performance bio-based construction materials with improved durability and reduced environmental impact.

A critical review on the effect of graphene oxide in fiber reinforced cementitious systems

The most widely used building materials nowadays are aggregates and cementitious material composites. Recently, the Graphene Oxide (GO) nanomaterial has grabbed a lot of attention in the material science of building materials. These graphene oxide-based cementitious composites have been studied in terms of their effect on microstructure, hydration mechanisms, mechanical and durable properties, as well as the performance of GO-cement composites, which transform ordinary cement materials into intelligent, sturdy, and long-lasting composites. An overview of the contemporary state-of-the-art effect of cementitious composites containing GO with fiber addition is presented in this paper. The main purpose of this paper is to critically review GO's performance with fibers in cementitious composites. In this review, we examined the properties like Workability, mechanical properties, and durability of cement-based materials along with the microstructural characterization. The tailored property of cementitious composite made with graphene oxide and fibers controls not only the secondary hydration mechanism but also improves the material’s mechanical performance, robustness and other multifunctional properties. The interaction of GO nanomaterial with fiber results in a remarkable and unique performance, such as the improvement of gel pores, the decrease of bigger capillary pores, the bridging of microcracks and the resistance to their spread, and the overall performance improvement of cementitious composites. Thus, this article aims to provide a substantial critical review of the impact of GO and fibers in cementitious composites.

Influence of drying temperature on coconut-fibers

The use of natural fibers in cementitious composites has been gaining prominence in engineering. The natural lignocellulosic fibers (NLFs) used in these composites have advantages such as reduced density, reduced fragmentation and concrete cracking, thus improving flexural performance and durability. Coconut-fiber is one of those natural fibers and its use presents technical, ecological, social and economic benefits, as it is improperly disposed of, representing a large waste of natural resources, in addition to causing environmental pollution.. Thus, composites reinforced with natural fibers are promising materials for the construction industry, as in addition to meeting the sustainability of buildings, there will also be a reduction in urban solid waste generated and gains for structures with the use of environmentally friendly materials that meet to active efforts and with greater durability. This work aims to evaluate the tensile behavior of green coconut-fibers subjected to different drying temperatures through chemical, thermal (TG/DSC), morphological, visual and mechanical analysis. Drying temperatures of 70 °C, 100 °C and 130 °C were analyzed and the results indicated that the drying temperature at 70 °C was satisfactory, providing fiber-reinforced composites with good tensile strength, combined with good ductility.

Seismic performance and damage analysis of steel-PVA hybrid fiber cementitious composites encased CFST columns

Using axial compression ratio, core concrete strength, steel tube thickness, and SPC strength as research variables, cyclic loading tests were conducted on 12 steel-polyvinyl alcohol (PVA) hybrid fiber cementitious composites (SPC) encased concrete-filled steel tube（CFST）columns to study the seismic performance of specimens under earthquake action, including failure mode, strength, stiffness, ductility, energy dissipation, and second-order effects. According to the study's findings, fiber bridging enabled SPC-encased CFST columns to effectively prevent cracks and maintain high integrity even after failing. The axial compression ratio, core concrete strength, and lateral bearing capacity were positively correlated, with a maximum bearing capacity increase of 46.9%, but their deformation capacity had decreased to varying degrees. The thickness and SPC strength of the steel tube exhibited excellent performance in terms of deformation capacity and energy consumption, with a maximum ductility coefficient of 6.21. In the overall statistical analysis of research variables, it was found that composite columns with core concrete strength grades higher than outer SPC strength had better seismic performance compared to other specimens. This article proposed an improved Park-Ang damage model that effectively evaluates the damage status of SPC-encased CFST columns. The model complies with the boundary conditions of the composite column, and the damage development trend reflected is consistent with experimental phenomena.

Feasibility of Recycled Carbon Fiber-Reinforced Polymer Fibers in Cementitious Composites: An Experimental Investigation

Feasibility of Recycled Carbon Fiber-Reinforced Polymer Fibers in Cementitious Composites: An Experimental Investigation

The effect of controlled fiber alignment of carbon fibers on the electrical properties of carbon fiber-cement composite under cyclic flexural loading

The desirable mechanical properties of fiber-reinforced cementitious composite (FRCC) have been proven in the past. In addition to the advancement of the material and material tailoring that significantly enhances the wide applications of FRCC, the fiber alignment control has been used to enhance the flexural strength recently. However, the investigation on the effect of aligned carbon fiber on the electrical properties especially under loading conditions is rare. In the study, an extrusion-based technology was applied to control the fiber alignment, and the effect of aligned carbon fibers on the electrical properties was studied under elastic and plastic conditions of the cyclic flexural loading. The results revealed the high sensitivity of the carbon fiber-cement composites with aligned fibers to the plastic deformation while all the composites with/without aligned fibers presented similar sensitivity to the elastic deformation.

Effect of aluminum hybrid additive on water absorption of fiber-cement composites

Effect of aluminum hybrid additive on water absorption of fiber-cement composites

Enhancing mechanical performance of green fiber cement composites: Role of eco-friendly alkyl ketene dimer on surfaces of hemp fibers

Fiber composites reinforced natural fibers have attracted more attention in sustainable building materials due to the high Young's modulus, availability, and biodegradability. However, poor interfacial bonding of the fiber-reinforced cement composites attributed to the intrinsically swelling-shrinkage behavior of the hydrophilic natural fibers, seriously limits the strength development of the composite. Here, an eco-friendly and low-cost surface treatment agent, alkyl ketene dimer (AKD), is innovatively introduced for reinforcing the combined effect of hemp fiber (HF)/cement matrix. The experimental approach includes the chemical modification of hemp fibers, followed by the direct preparation of fiber cement composites. Fourier transformation infrared spectroscopy (FTIR) and water absorption test analyses confirmed that the modified HF surface was successfully grafted with AKD, leading to superior hydrophobic characterization and reduced swelling-shrinking behavior. Adding the modified HF to the cement composites effectively enhanced their mechanical properties and toughness capacity by strengthening the interfacial bond of modified HF/Mortar. The modified fiber-reinforced mortar has the highest increment (28 % in compressive strength and 24 % in flexural strength, respectively) from 7 d to 28 d among all investigated mortars. Furthermore, the micro-observation of fractured mortar composites supports the strengthened interface of the modified fibers/cement matrix. The study provides a feasible and practical approach to improving the comprehensive strength properties of hemp fiber-reinforced cement composites. It benefits the practical industrial-scale application of biomaterials in low-cost housing, thus enhancing sustainability.

Simultaneously enhanced mechanical and electromagnetic interference shielding properties of steel slag-recycled carbon fiber cementitious composites via wet-grinding process

Simultaneously enhanced mechanical and electromagnetic interference shielding properties of steel slag-recycled carbon fiber cementitious composites via wet-grinding process

Novel surface functionalization of cellulose fibers with polyurethane prepolymers in fiber cement composites: Impact on final properties and potential benefits for the production process

The objective of this research was to perform a deep exploration of cellulose polyurethane (PU) fibers used in fiber cement boards for usage in building applications. Grafting treatment was performed on cellulose fibers with PU-pre-polymers, through a synthesis method using propylene carbonate solvent medium, followed by a cleaning step. Fiber cement boards were prepared thorough cement and limestone dispersion followed by a dewatering process, to roughly mimic the Hatschek production process. The experiments confirmed that grafted cellulose fibers can present lower water absorption (∼10 %) and greater fiber preservation, when embedded in alkaline matrix. Although the mechanical performance of fiber cement composites prepared with cellulose-PU fibers were not appreciably different, superior ability to drain water from the green cement sheet was demonstrated, which can provide great benefits during the production process. It’s worth mentioning that cellulose fiber is added in the air cured fiber cement formulation as a process aid agent to retain fine aggregates, and mechanical reinforcement is mainly carried out by the synthetic fibers. From the fiber cement production perspective, the reduced water retention showed in the green sheet can be beneficial in different production processes, e.g. the Hatschek or flow-on, in two ways: First, by possibly reducing the number of stops, as a lighter green sheet would be less prone to drop from the machine, and second, due to lower vacuum applied, possibly avoiding segregation and producing more homogeneous boards.

Interfacial properties of high-strength, limestone-calcined clay cement (LC3) matrix and PE fibers, surface-modified using dopamine and tannic acid

Polyethylene (PE) fibers exhibit superb mechanical and geometrical properties with respect to their use as dispersed reinforcement in cement-based materials. However, the fiber–matrix interaction in such composites is known to be poor due to the lack of active functional groups on the fibers’ polymeric backbones, leading to the limited affinity of PE fibers toward water-based, cementitious matrices. Therefore, to exploit the reinforcing effect of PE fibers in cementitious composites fully, fiber–matrix interactions need to be enhanced by functionalizing the fibers with hydrophilic polar groups. In the article at hand, the effects of dopamine (DA) and tannic acid (TA) surface functionalization and their combinations on interfacial properties with a high-strength, limestone-calcined clay cement (LC3) matrix have been explored. To assess the morphological changes as well as the physical–chemical properties of the fibers under investigation, they were characterized by environmental scanning electron microscopy (ESEM), Energy-dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and zeta-potential (ZP). The presence of a DA and TA (DA/TA) coating layer was confirmed by ESEM and AFM images for modified samples, which showed rougher surfaces along with uniform coating distributions, proven via mapping images as well. TGA results yielded coating amounts of 7.8, 1.5, 1.5, 2.3 and 1.0 wt% for samples with DA/TA portions of 100/0, 70/30, 50/50 and 30/70 and 0/100, respectively. Compared with the pristine PE fiber, the DA/TA surface modification of PE fibers improved the tensile strength and modulus of elasticity values by 29% and 36%, respectively. According to micromechanical investigations, maximum pullout force and interfacial shear strength in specimens with modified fibers were three times higher than for the reference fibers, while fiber pullout energy was as much as six times higher