Search Results (39)

This study addresses the need for thermomechanically robust materials for high-temperature environments by investigating fabric-reinforced composites produced through polymer infiltration and thermal pressing using phenol-formaldehyde (PF) and epoxy (ER) resins. Experimental validation was required due to the lack of comparative data across different textile reinforcements under identical conditions. Seven technical fabrics—carbon, aramid, basalt, silica, fiberglass, asbestos, and a carbon/aramid hybrid—were used as reinforcements. Mechanical testing revealed that carbon- and hybrid fiber composites exhibited the highest tensile (up to 465 MPa) and compressive strengths (up to 301 MPa), particularly when combined with ER. Conversely, the use of PF generally resulted in a 30–50% reduction in mechanical strength. However, PF-based composites demonstrated superior thermal resistance, with the silica/PF combination showing the lowest back-face temperature (401 °C), up to 37% lower than other pairings. Thermal conductivity ranged from 0.041 to 0.51 W/m·K, with PF-based systems offering 6–12% lower values on average compared to ER-based analogs. Morphological analysis confirmed better interfacial bonding in ER composites, while PF systems showed higher structural integrity under thermal loading. Overall, the results emphasize the trade-offs between mechanical strength and thermal protection depending on the fabric–resin combination. Among all variants, the silica fabric with PF demonstrated the most balanced performance, making it a promising candidate for thermomechanical applications. Full article

Traditional concrete has low tensile strength, is prone to cracking, and has poor durability, which limits its scope of application. Basalt Fiber Textile–Reinforced Concrete (BTRC), a new type of fiber-reinforced cement material, offers advantages such as light weight, increased strength, improved crack resistance, and high durability. It effectively addresses the limitations of traditional concrete. However, the tensile properties of BTRC have not been fully studied, especially with fine aggregate concrete as the matrix, and there are few reports on this topic. Therefore, this study conducted uniaxial tensile tests of Basalt Textile–Reinforced Fine Aggregate Concrete (BTRFAC) and systematically investigated the effects of two mesh sizes (5 mm × 5 mm and 10 mm × 10 mm) and two to four layers of fiber mesh on the tensile strength, strain hardening behavior, crack propagation, and ductile tensile mechanical properties of BTRFAC thin slabs. The tests revealed that an increase in the number of fiber mesh layers significantly reinforced the material’s tensile strength and ductility. The tensile strength of the 5 mm mesh specimen (four-layer mesh) reached 2.96 MPa, which is 193% higher than plain concrete, and the ultimate tensile strain increased by 413%. The tensile strength of the 10 mm mesh specimen (four-layer mesh) was 2.12 MPa, which is 109% higher than plain concrete, and the ultimate tensile strain increased by 298%. The strength utilization rate of the 5 mm and 10 mm mesh fibers was 41% and 54% respectively, mainly due to the weakening effect caused by interface slippage between the fiber mesh and the matrix. An excessively small mesh size may lead to premature debonding from the matrix, but its denser fiber distribution and larger bonding area exhibit better strain hardening characteristics. More than three layers of fiber mesh can significantly improve the uniformity of crack distribution and delay propagation of the main crack. A calculation formula for the tensile bearing capacity of BTRFAC thin slabs is proposed, and the error between the theoretical value and the experimental value was very small. This research provides a theoretical basis and reference data for the design and application of basalt fiber mesh–reinforced concrete thin slabs. Full article

The present work constitutes the initial experimental effort to characterise the dynamic tensile performance of basalt fibre grids employed in TRM systems. The tensile behaviour of a bi-directional basalt fibre grid was explored using a high-speed servo-hydraulic testing machine with specialised grips. Deformation and failure modes were captured using a high-speed camera. Tensile strain values were extracted from the recorded images using the MATLAB computer vision tool, ‘vision.PointTracker’. The specimens, consisting of one and four rovings, were tested at intermediate (1–8/s) and quasi-static (10⁻³/s) strain rates. After the tensile tests, scanning electron microscopy (SEM) analyses were performed to examine the microscopic failure of the material. Linear and non-linear stress–strain behaviours were observed in the range of 10⁻³ to 1/s and 4 to 8/s, respectively. Tensile strength, ultimate strain, toughness, and elastic modulus increased at intermediate strain rates. Overall, the dynamic increase factors for these properties, except for the latter, were between 1.4 and 2.3. At the macroscopic level, the grid failed in a brittle manner. However, microscopic analyses revealed that the failure modes of the fibre and polymer coating were strain-rate sensitive. The enhanced tensile performance of the grid under dynamic loading conditions rendered it suitable for retrofitting structures prone to extreme loading conditions. Full article

The article presents the results of research on the impact of the use of an original, innovative method of deposition of Parylene C on the functional properties of fabrics with various potential applications (e.g., thermal and chemical protective clothing, packaging, covers and others). Verification of the effects of the method used was based on interdisciplinary research taking into account the impact of coating fabrics on changes in their structure (micro-CT), surface properties (contact angle), barrier properties (water and chemical liquid wetting), electrostatic properties (charge decay), biophysical properties describing heat and mass transfer (by the Alambeta system and thermal imaging) and flammable properties. Four fabrics made of synthetic organic fibres (meta-aramid, para-aramid) and natural inorganic fibres (basalt) were selected for testing. Given the complex structure of textile substrates, the results confirmed that the two assumed thicknesses of the Parylene C coating were consistent with the actual measurements. The findings indicated that the coatings significantly reduced water and acid absorption in the fabrics compared to unmodified ones. Thermal insulation property tests revealed that coated fabrics exhibited higher thermal conductivity than unmodified fabrics. Additionally, the presence of Parylene C on aramid fabrics resulted in a modest increase in their ignition resistance. Full article

This paper presents the results of research on conductive layers dedicated to flexible photovoltaic cells based on semiconductors integrated with a textile substrate. The presented work is part of a broader project aimed at producing flexible solar cells based on the CdTe semiconductor component and manufactured directly on textiles. The research focuses on the selection of textile substrates and contact materials, as well as the methods of their application. This study compares three types of fabrics (basalt, glass, and silicone fibers) and three metals (copper, molybdenum, and silver), evaluating their mechanical and electrical properties. During the experiments, flexible metallic layers with a thickness ranging from 160 to 415 nm were obtained. Preliminary experiments indicated that metallic layers deposited directly on textiles do not provide adequate conductivity, reaching the levels of several hundred Ω/sq and necessitating the introduction of intermediate layers, such as screen-printed graphite. The results show that molybdenum layers on basalt fabrics exhibit the lowest increase in resistance after dynamic bending tests. The obtained relative resistance changes in Mo layers varied from 50% to as low as 5% after a complete set of 200 bending cycles. This article also discusses current challenges and future research directions in the field of textile-integrated photovoltaics, emphasizing the importance of further technological development to improve the energy efficiency and durability of such solutions. Full article

Most historical buildings and structures in Oman were built using unreinforced stone masonry. These structures have deteriorated due to the aging of materials, environmental degradation, and lack of maintenance. This research investigates the physical, chemical, and mechanical properties of the local building materials. It also presents the findings of an experimental study on the in-plane shear effectiveness of a modern strengthening technique applied to existing stone masonry walls. The technique consists of the application of a textile-reinforced mortar (TRM) on one or two faces of the walls. Shear loading tests of full-scale masonry samples (1000 mm width, 1000 mm height, and 350 mm depth) were carried out on one unreinforced specimen and six different cases of reinforced specimens. The performances of the unreinforced and reinforced specimens were analyzed and compared. We found that strengthened specimens can resist in-plane shear stresses 1.5–2.1 times greater than those of the unreinforced specimen; moreover, they demonstrate ductility rather than sudden failure, due to the presence of fiberglass and basalt meshes, which restrict the opening of cracks. Full article

In this investigation, the effects of different fabrics with 0.20% carbon fiber textile (CFT), 0.21% glass fiber textile (GFT), and 0.25% basalt fiber textile (BFT) on the properties of TR-UHPC were investigated by axial tensile tests. A bending test of the BFT-UHPC pavement slab was carried out. In terms of axial tensile performance, the fiber textiles ranked in the following sequence: CFT, BFT, and GFT. Additionally, the corresponding increases in the initial cracking strength and ultimate tensile strength were 18.0% and 21.9% for the CFT, 12.0% and 16.0% for the BFT, and only 9.1% and 8.0% for the GFT, respectively. Increasing the textile reinforcement ratio of the BFT from 0.25% to 0.50% improved the cracking stress and peak stress of the specimen by 12.0% and 15.9%, respectively. Moreover, the ultimate strain of the 0.50%-BFT reinforcing case was 1.4 times that of the 0.25%-BFT reinforcing case and 2.6 times that of the unreinforced specimen in terms of ductility. The results of the stacking test on the BFT reinforced UHPC pedestrian slab indicate that the mid-span deflection of the test slab under normal use load is 0.775 mm, which is only 19.8% of the deflection limit. Additionally, the test slab remained in the elastic stage without any cracking. The BFT effectively enhanced the toughness of the UHPC thin slab after cracking. It is expected to be applied as a novel structure to bridge pedestrian slabs, bridge decks, and other thin UHPC members, thereby improving the durability and mechanical properties of bridge structures. Full article

This work aims to evaluate experimentally different fibers and resins in a topologically optimized composite component. The selected ones are made of carbon, glass, basalt, flax, hemp, and jute fibers. Tailored Fiber Placement (TFP) was used to manufacture the textile preforms, which were infused with two different epoxy resins: a partly biogenic and a fully petro-based one. The main objective is to evaluate and compare the absolute and specific mechanical performance of synthetic and natural fibers within a component framework as a base for improving assessments of sustainable endless-fiber reinforced composite material. Furthermore, manufacturing aspects regarding the different fibers are also considered in this work. In assessing the efficiency of the fiber-matrix systems, both the specific stiffness and the specific stiffness relative to carbon dioxide equivalents (${\mathrm{CO}}_2^{\mathrm{eq}.}$) as measures for the global warming potential (GWP) are taken into account for comparison. The primary findings indicate that basalt and flax fibers outperform carbon fibers notably in terms of specific stiffness weighted by ${\mathrm{CO}}_2^{\mathrm{eq}.}$. Additionally, the selection of epoxy resin significantly influences the assessment of sustainable fiber-plastic composites. Full article

The majority of historical buildings and structures in Oman were built using unreinforced stone masonry. These structures have deteriorated due to ageing of materials, environmental degradation, and lack of maintenance. This research investigates the physical, chemical, and mechanical properties of local building materials and the results of an experimental study on the out-of-plane bending effectiveness of an innovative strengthening method applied to existing masonry walls. The technique consists of the application of a basalt textile-reinforced sarooj mortar (TRM) on one face of the walls. Bending tests of masonry wall samples (1000 mm width, 2000 mm height, and 350 mm depth) were carried out on one unreinforced specimen and three different cases of reinforced specimens. The performance of unreinforced and reinforced specimens was analyzed and compared. The strengthened specimens were able to resist moments of out-of-plane bending 2.5 to 3 times greater than those of unreinforced specimen (160–233% increase). Moreover, the strengthened walls were able to sustain higher deformations (deflections) than the unreinforced specimen ranging from 20 to 130%. The results showed that using TRM was effective for the out-of-plane strengthening of stone masonry using a local material (sarooj) that is compatible with existing stone masonry building materials. Full article

The use of fabrics in the form of grids embedded in cementitious matrices—usually termed as textile-reinforced mortar, fiber-reinforced cementitious matrix, or textile-reinforced concrete—demonstrate a more stable performance in elevated temperature conditions compared with fiber-reinforced polymers. This study investigated the residual tensile properties of bare yarns and fabrics in the form of grids embedded in a cementitious mortar after exposure to 100 °C, 200 °C, and 300 °C. Three different coated fabric textiles were used as reinforcement: carbon, basalt, and glass. Additionally, scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermos-gravimetric analysis (TGA) were conducted to evaluate potential changes in the internal structure of the fibers and the mortar. The cracking stress, the tensile strength, and the ultimate strain of the composite specimens were increased after exposure to 100 °C, while only carbon and glass fiber grids retained their effectiveness up to 200 °C. At 300 °C, the coupons reinforced with carbon and basalt fibers deteriorated rapidly. Only the glass counterparts showed an improved overall performance due to fiber contraction and the differences in the coating material. The results highlight the differences in the performance of the three fiber types and the important role of the coating material in the overall composite behavior. Full article

This paper presents an experimental study to strengthen flexure-deficient reinforced concrete beams using textile-reinforced mortars (TRMs). A set of seven reinforced concrete beams were strengthened using basalt and carbon TRMs. The current study utilised textiles with almost similar physical properties to strengthen reinforced concrete (RC) beams. All the studied beams were strengthened at their soffit to evaluate the effectiveness of textile fibres, the number of layers and the strengthening configuration. The experimental results showed that beams strengthened using carbon and basalt textile-reinforced mortar performed equally better in terms of overall performance with inherent textile slippage after the peak load. The flexural load capacities of the beams were strengthened with one layer, and three layers were higher when compared to the control beam. For the basalt TRM one, three and five layers registered an increment of 8.3%, 20.7% and 30.3% of ultimate strengths over the unstrengthened specimen. Similarly, for the carbon TRM one, three and five layers recorded an increment of 14.2%, 15.3% and 32.3% of ultimate strengths over the control specimen. Five-layered specimens with end U-wraps successfully mitigated premature debonding, along with registering maximum load capacity, and digital image correlation (DIC) was performed to monitor real-time crack width, crack patterns and spacing and to compare the load and displacement responses from all the tested specimens. Full article

The proposed study combines sprayed glass fiber-reinforced mortar and basalt textile-reinforcement to harness the favorable properties of each component to obtain a composite material that can be used for strengthening of existing structures. This includes crack resistance and a bridging effect of glass fiber-reinforced mortar and the strength provided by the basalt mesh. In terms of weight, mortars containing two different glass fiber ratios (3.5% and 5%) were designed, and tensile and flexural tests were conducted on these mortar configurations. Moreover, the tensile and flexural tests were performed on the composite configurations containing one, two, and three layers of basalt fiber textile reinforcement in addition to 3.5% glass fiber. Maximum stress, cracked and uncracked modulus of elasticity, failure mode, and average tensile stress curve results were compared to determine each system’s mechanical parameters. When the glass fiber content increased from 3.5% to 5%, the composite system without basalt textiles’ tensile behavior slightly improved. The increase in tensile strength of composite configurations with one, two, and three layers of basalt textile reinforcement was 28%, 21%, and 49%, respectively. As the number of basalt textile reinforcements increased, the slope of the hardening part of the curve after cracking clearly increased. Parallel to the tensile tests, four-point bending tests showed that the composite’s flexural strength and deformation capacities increase as the number of basalt textile reinforcement layers increase from one to two. Full article

Recently, innovations in textile-reinforced concrete (TRC), such as the use of basalt textile fabrics, the use of high-performance concrete (HPC) matrices, and the admixture of short fibers in a cementitious matrix, have led to a new material called fiber/textile-reinforced concrete (F/TRC), which represents a promising solution for TRC. Although these materials are used in retrofit applications, experimental investigations about the performance of basalt and carbon TRC and F/TRC with HPC matrices number, to the best of the authors’ knowledge, only a few. Therefore, an experimental investigation was conducted on 24 specimens tested under the uniaxial tensile, in which the main variables studied were the use of HPC matrices, different materials of textile fabric (basalt and carbon), the presence or absence of short steel fibers, and the overlap length of the textile fabric. From the test results, it can be seen that the mode of failure of the specimens is mainly governed by the type of textile fabric. Carbon-retrofitted specimens showed higher post-elastic displacement compared with those retrofitted with basalt textile fabrics. Short steel fibers mainly affected the load level of first cracking and ultimate tensile strength. Full article

This paper presents an investigation into the ultimate and serviceability behavior of concrete beams strengthened in flexure with basalt-textile-reinforced polymer mortar (BTRM). The bond performance at the interface between the BTRM and concrete was studied by performing single shear tests, and the effectiveness of using an adhesion promoter and impregnated resin for bond enhancement was explored. The results suggested that using an adhesion promoter and impregnated resin can improve the interfacial stress transfer and ensure the tensile failure of the basalt textile in BTRM. Afterward, four-point bending tests were conducted to study the flexural performance of strengthened beams. It was found that the flexural strength of strengthened beams increased with the amount of textile, and the strength increase was more prominent for the strengthened beams with end anchorages. The increase in the failure force was up to 37% for the beam strengthened with five layers of the textile and an end anchorage. The calculated flexural strength exhibited a percentage error of no more than 7% compared to the test results. In addition, the Bischoff-I Equation can closely estimate the effective moment of inertia and provide an accurate prediction of deflection for strengthened beams. Full article

Under corrosive environments, concrete material properties can deteriorate significantly, which can seriously affect structural safety. Therefore, it has important engineering applications to improve the durability performance at a lower economic cost. This paper proposes a new, highly durable concrete using inexpensive construction materials such as basalt fiber, sodium methyl silicate, and inorganic aluminum salt waterproofing agent. With the massive application of sewage treatment projects, the problem of concrete durability degradation is becoming more and more serious. In this paper, five types of concrete are developed for the sewage environment, and the apparent morphology and fine structure of the specimens after corrosion in sewage were analyzed. The density, water absorption, and compressive strength were measured to investigate the deterioration pattern of concrete properties. It was found that ordinary concrete was subject to significant corrosion, generating large deposits of algae on the surface and accompanied by sanding. The new concrete showed superior corrosion resistance compared to conventional concrete. Among other factors, the inorganic aluminum salt waterproofing agent effect was the most prominent. The study found that the strength of ordinary concrete decreased by about 15% in the test environment, while the new concrete had a slight increase. Comprehensive evaluation showed that the combination of basalt fiber and inorganic aluminum salt waterproofing agent had the best effect. Its use is recommended. Full article