Aug 2026· Materials· Vol 19· 0 citations· 38 references
Medicine
Abstract
This study investigates the strength development, crack evolution and toughening mechanism of basalt fiber-reinforced desert sand high-strength concrete. An L9(33) orthogonal design was first used to optimize the reference mixture, after which basalt fibers with volume fractions of 0, 0.3%, 0.4% and 0.5% were incorporated. Mechanical testing, digital image correlation, SEM, XRD, TG and FTIR were combined to clarify the relationship among fiber dosage, crack propagation and microstructural reinforcement mechanisms. The optimized matrix mixture was obtained with a water-to-binder ratio of 0.32, a desert sand replacement ratio of 40% and a fly ash content of 20%. The incorporation of basalt fiber had little influence on the 28 d compressive strength, whereas the splitting tensile strength was markedly improved. The highest splitting tensile strength was observed in the 0.4% fiber group, reaching 5.46 MPa, which was 12.81% higher than that of the reference mixture. DIC results showed that basalt fiber reduced strain localization and limited crack opening. The 0.5% group had the lowest COD, while the 0.4% group showed a better balance among tensile strength, strain redistribution and crack-opening control. SEM observations showed fiber bridging and fiber–matrix interaction near the fracture region. Meanwhile, XRD, TG-DTG and FTIR showed no obvious changes in the main phases or functional groups, indicating that the improvement was mainly related to the physical crack-control effect of basalt fibers rather than chemical modification of the matrix. Overall, 0.4% basalt fiber was identified as the preferred dosage for the present system.
This study investigates the effects of alkali-treated rice straw fibers on the mechanical performance and interfacial characteristics of concrete. To address the limited understanding of the combined influence of fiber length and dosage in rice-straw-fiber-reinforced concrete, rice straw fibers with lengths of 1, 2, and 3 cm were pretreated in a 2% sodium hydroxide solution and incorporated into concrete at volume fractions of 0.3%, 0.5%, and 0.7%. Compressive strength was evaluated at 3, 7, and 28 days to characterize early-age strength development and the standard 28-day mechanical performance, whereas splitting tensile strength and flexural strength were measured at 28 days because these tests were intended to assess the mature crack-bridging and toughness-related behavior of the fiber-reinforced concrete. Scanning electron microscopy was used to observe the surface morphology of the fibers and the fiber–matrix interface. The results show that the incorporation of rice straw fibers generally decreased compressive strength, although the trend depended on fiber length and dosage. In contrast, fiber addition improved the tensile and flexural performance of concrete. The maximum increase in splitting tensile strength was about 17.4%, and the flexural strength increased by up to 58% compared with plain concrete. Microscopic observations indicated that alkali treatment roughened the fiber surface and improved mechanical interlocking with hydration products, thereby promoting crack bridging and energy dissipation during fracture. This study clarifies the trade-off between compressive-strength reduction and tensile/flexural toughening in alkali-treated rice straw fiber concrete.
Yating Zheng, Jiawen Huang, Zhibin Ye et al.· Frontiers in Materials· 0 citations
Coal gangue fine aggregate (CGFA) can reduce the consumption of natural sand, but its high water absorption and heterogeneous pore structure may compromise concrete performance. This study investigates whether basalt fiber (BF) can improve the mechanical response and damage resistance of spontaneous-combustion CGFA concrete. Seventeen concrete mixtures were prepared by replacing natural fine aggregate with CGFA at 0, 10, 20, 40, and 50% and incorporating BF at 0, 0.10, 0.15, and 0.20 vol%. Cube compressive, axial compressive, splitting tensile, flexural, and dynamic elastic-modulus tests were conducted, and the microstructural mechanisms were examined using scanning electron microscopy. Strength and stiffness generally increased first and then decreased with increasing CGFA content, with the most favorable overall response at approximately 20% replacement. BF improved crack control and deformation capacity, and 0.15 vol% produced the highest strengthening efficiency, particularly for splitting tensile and axial compressive strength. Excessive BF reduced the reinforcing benefit because of poorer dispersion and fiber agglomeration. Moderate CGFA replacement and optimized BF dosage produce a synergistic enhancement through interfacial densification, crack bridging, and improved stress transfer. Empirical strength models are proposed for trend-level prediction within the investigated material system.
This study investigates the flexural behaviour of concrete made with wooden ash (WA) as a partial cement replacement and the addition of nylon fibres (NF) as a fiber reinforcement. Four concrete mixes containing 0%, 5%, 10%, and 15% WA replacement and 1% constant NF were casted. Beam specimens (150 × 100 × 500 mm) were tested under four-point bending to evaluate comprehensive flexural behaviour, including strength, crack resistance, stiffness degradation, ductility, deformation capacity, energy absorption, toughness, and flexural performance (FP) factor. The results indicate that mix-10% achieved the highest flexural strength of 4.8 MPa with a 50% improvement compared to the control mix (3.19 MPa). Furthermore, it also shows the highest crack resistance ratio (0.644), indicating improved resistance to crack initiation. Also, mix-15% shows the highest peak load (23.30 kN), post-cracking SR (1.9), total toughness (30.60 kN·mm), and FP factor (89.79 kN·mm). Furthermore, the stiffness response showed a reduction in initial stiffness from 32.22 kN·mm−1 to 3.65 kN·mm−1, suggesting a transition from brittle to ductile structural behaviour. The improved performance is attributed to the pozzolanic reactivity of WA, combined with the crack-bridging mechanism of NF. The findings concluded that concrete made with 10%–15% WA with NF provides an optimal balance between strength, toughness, and deformation capacity. Therefore, it can be used for structural applications requiring enhanced durability, impact resistance, and damage tolerance.
Muhammad Sheraz, Jawad Ahmad· Materials Research Express· 0 citations
Recycled aggregate concrete (RAC) offers an effective approach to reducing the environmental burden associated with construction and demolition waste. In this study, a fiber-reinforced RAC was developed by replacing part of the cement with fly ash and ground granulated blast-furnace slag, while glass fibers or basalt fibers were incorporated as reinforcing materials. A systematic experimental program was conducted to evaluate the mechanical behavior of the proposed concrete under different saturation conditions. The results show that the best toughness performance was achieved in the natural moisture state. In comparison, compressive and flexural strengths reached their maximum values under dry conditions, whereas splitting tensile strength peaked in the natural state. Based on the experimental data, prediction equations were established for the splitting tensile and flexural strengths by considering both saturation degree and fiber content. A stress–strain model under uniaxial compression was also developed. In addition, scanning electron microscopy (SEM) was employed to examine the fiber–matrix interface and hydration products, thereby clarifying the microstructural characteristics of the concrete at different saturation levels.
Jie Zhou, Tengfei Guo, Xiang Li et al.· Buildings· 0 citations
ABSTRACT Concrete is brittle substance whose tensile strength and flexural strength are low and may easily crack and its lifespan is limited. The proposed research aims at assessing how the addition of nylon fiber affects the mechanical and workability of M30 grade reinforced cement concrete (RCC). The originality of this study is that the nylon fibers used are used at optimal dosage (0.25% and 0.5% by volume) in order to improve both strength and durability without impairing the workability. Six series of specimens were cast and experimented on compressive, split tensile and flexural strength, and slump cone testing of fresh concrete workability. The findings showed that the compressive, split tensile and flexural strengths were increased by 11, 14 and 17 percent respectively by the addition of 0.5 percent nylon fiber over plain M30 concrete. The enhancement in mechanical performance is attributed to improved fiber matrix interfacial bonding and crack-bridging mechanisms provided by the dispersed nylon fibers. The fibers effectively delay crack propagation and redistribute tensile stresses within the concrete matrix. Engineering wise, the nylon fiber-reinforced concrete is a cost-effective and structural-friendly substitute of structural application in which enhanced tensile and flexural strengths are needed.
Dharmaraj Rajalinggam, Sri Aiswarya Devadass, Saravanan Ramasamy et al.· Matéria· 0 citations
This study examines the fracture and mechanical performance of hybrid fiber-reinforced high-strength concrete (HFRHSC) with different water-to-binder (W/B) ratios. Six mixtures incorporating hybrid combinations of steel, polymer, glass, and basalt fibers were investigated at W/B ratios of 0.42, 0.31, and 0.25. The synergistic effects of the fiber systems were evaluated in terms of compressive strength, splitting tensile strength, flexural behavior, fracture energy, residual strength, and toughness indices. Fracture properties were assessed using three-point bending tests on notched beams, where load-crack mouth opening displacement (CMOD) and load–deflection curves were used to characterize post-cracking behavior. In addition, bilinear softening and multi-exponential models were applied to reproduce the experimental load–CMOD response and estimate fracture energy. The multi-exponential model provided a more accurate representation of the nonlinear post-peak response, with coefficients of determination generally exceeding 0.95, whereas the bilinear model remained simpler and more suitable for practical engineering interpretation. The results show that hybridization substantially improved fracture resistance, particularly at lower W/B ratios. The steel–glass fiber system achieved approximately 54% higher fracture energy, a 40% improvement in toughness index, and 35% higher peak load-carrying capacity compared to the control mixture. The steel-polymer system at W/B = 0.31 exhibited the highest energy absorption capacity, with a 124% increase in total energy absorbed up to 10 mm deflection. These findings demonstrate that properly selected hybrid fiber systems can significantly improve crack resistance and post-cracking energy dissipation in HFRHSC, while analytical modeling provides a useful tool for interpreting load-CMOD behavior and fracture energy.
P. Smarzewski, T. A. Tawfik, Mohamed Abdellatief· International Journal of Civ...· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.
