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·m^1/2 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.

Fiber–cement composites have been increasingly studied for sustainable construction applications, but durability issues—particularly fiber degradation in alkaline environments—remain a challenge. This study aimed to evaluate the individual and combined effects of furfurylated sisal fibers and nanoclay additions on the physical and mechanical performance of autoclaved fiber–cement composites, seeking to enhance fiber durability and matrix compatibility. All the composites were formulated with CPV-ARI cement and partially replaced with agricultural limestone to reduce the environmental impact and production costs. Sisal fibers (2 wt.%) were chemically modified using furfuryl alcohol, and nanoclays—both hydrophilic and surface-functionalized—were incorporated at 1% and 5% of cement weight. The composites were characterized for physical properties (density, water absorption, and apparent porosity) and mechanical performance (flexural and compressive strength, toughness, and modulus). Furfurylation significantly improved fiber–matrix interaction, leading to higher flexural strength and up to 100% gain in toughness. Nanoclay additions reduced porosity and increased stiffness, particularly at 5%, though excessive content showed diminishing returns. The combination of furfurylated fibers and functionalized nanoclay provided the best results in maintaining a compact microstructure, reducing water absorption, and improving mechanical resilience. Optical microscopy confirmed improved fiber dispersion and interfacial bonding in composites containing furfurylated fibers and functionalized nanoclay. These findings highlight the effectiveness of integrating surface-treated natural fibers with pozzolanic additives to enhance the performance and longevity of fiber–cement composites.

This study explores the use of thermally treated granite slurry waste to mitigate the mineralization of sisal fibers in fiber‐cement composites. Granite waste was thermally treated at 600°C and 900°C, and the treated materials were analyzed using X‐ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Sisal fibers, alkali‐treated with 1.7% NaOH, were incorporated into fiber‐cement composites, where 15% and 30% of the cement was replaced by treated and untreated granite. Composites with 15% of granite treated at 600°C and 900°C showed improvements in compressive strength of up to 12% and 18%, respectively, compared to the control. The flexural strength increased by 10% with 15% granite treated at 900°C. However, the untreated granite at 30% replacement increased porosity by 25% and water absorption by 18%, negatively affecting the mechanical properties. Aging tests showed a 40% loss in compressive strength, while composites with 30% granite treated at 900°C maintained their flexural strength, making them more durable. These findings highlight the potential of thermally treated granite waste to enhance the sustainability and performance of fiber‐cement composites in construction.

This study investigates the potential of Fourier-transform infrared spectroscopy combined with chemometric modelling to predict mechanical properties of thermally modified Pinus elliottii wood. Specimens were subjected to three thermal treatments (160 °C, 200 °C and 240 °C) and analysed using second-derivative Fourier-transform infrared spectra. Principal component analysis revealed clear spectral separation among treatments, while partial least squares regression partial least squares regression was employed to model bending modulus, bending strength, and hardness (radial and tangential). In addition to regression modelling, spectral–mechanical relationships were examined through Pearson correlation analysis across all wavenumbers, enabling the identification of highly predictive spectral regions and their correspondence with structural wood compounds. Fourier-transform infrared spectra captured consistent chemical changes, especially in regions associated with cellulose (∼1030 cm ⁻¹ ), lignin (∼1230 cm ⁻¹ ) and hemicelluloses (∼1730 cm ⁻¹ ). Partial least squares regression models exhibited high predictive accuracy for bending modulus ( R ² = 0.93; RPD = 2.18) and tangential hardness ( R ² = 0.91; RPD = 2.05), indicating excellent robustness. In contrast, bending strength and radial hardness presented lower performance ( R ² = 0.81 and 0.74, respectively), attributed to greater mechanical variability and weaker spectral contrast. Therefore, this study demonstrates that Fourier-transform infrared spectroscopy, supported by chemometric tools such as variable importance in projection scoring and spectral correlation, enables fast, non-destructive and accurate prediction of wood mechanical behaviour of thermally modified pine woods. This approach represents a viable strategy for sustainable quality assessment of engineered wood products.