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Highlights S2‐glass fiber reinforced plastics (S2‐GFRP) and basalt fiber reinforced plastics (BFRP) have emerged as crucial materials due to their exceptional mechanical properties, and milling of composite materials plays an important role in achieving desired properties. However, they have proven challenges due to relative inhomogeneity compared with metals, resulting unpredictability in quality of milling operations. The objective of this work is to investigate the effect of cutting parameters, tool geometry and tool surface materials on the surface quality of composites using burrs as a metric. S2‐GFRP and BFRP composites were produced by the vacuum infusion method. Helical and straight flute end mills were manufactured from high‐speed steel (HSS) and carbide rounds, and half of them were coated with titanium nitride using reactive magnetron sputtering technique. Taguchi L18 orthogonal array is used to determine the effect of tool material, tool angle, coating, cutting direction, spindle speed, and feed rate on the machining quality of S2‐GFRPs and BFRPs with respect to burr formations. Milling experiments were conducted under dry conditions and then the burrs were imaged to calculate the total area and length. Statistical analysis was also performed to optimize the machining parameters and tool type for ensuring the structural integrity and performance of the final composite parts. The results showed that the selection of tool material has the most significant impact on the burr area and length of the machined surface. The novel image analysis allows to analyze the extent of the burr size with a desirable operation speed for industrial applications. Aerospace grade S2‐Glass (S2‐GFRP) and basalt fiber reinforced plastics (BFRP) were manufactured. Carbide and HSS end mills were fabricated and coated with titanium nitride protective layer. FRPs were machined at various process parameters designed by Taguchi method. Distinctive image processing was firstly used to compute milling induced Burr area and length. Statistical analysis was performed to quantify the contribution of parameters and optimize milling. [ABSTRACT FROM AUTHOR]

To expand the applications of hybrid fiber composites in structural engineering applications, it is essential to study their fatigue behavior. The tensile and fatigue performance of unidirectional hybrid basalt/glass epoxy composites made with vacuum‐assisted resin infusion molding are investigated in this research. The sequencing influence on tensile properties was assessed using the two configurations of basalt/glass fiber epoxy hybrid fiber composites, namely GBBBG and BGBGB, having nearly equal volume fractions. According to the test results, hybrid fiber composites showed a positive hybrid effect on their tensile strength. Both hybrid layups showed higher tensile strengths (3.5% to 10.5%) than GFRPs and BFRPs. The GBBBG laminate has slightly higher fatigue resistance than BGBGB laminate under tension–tension (T–T) fatigue. Scanning electron microscopy (SEM) images verify the fatigue failure modes, which include fiber, matrix cracking, delamination, and debonding. The DMA analysis showed the lower adhesion efficiency of hybrid fiber composites, signifying lower damping properties. Highlights: The basalt/glass fiber hybrid fiber composites were fabricated using VARIM.The static and fatigue properties of basalt/glass fiber hybrid fiber composites were studied.The stiffness degradation and hysteresis were calculated for the composites tested.The DMA was performed, and Tg, storage modulus, and adhesion efficiency factor were calculated. [ABSTRACT FROM AUTHOR]

In the present research, glass and basalt fiber-reinforced polypropylene composites' behaviour in quasi-static and dynamic conditions is studied. Composites were fabricated by vacuum assisted Compression molding method. Composites failure under quasi-static tension and compressive conditions was studied along with its failure behaviour under low-velocity impact and super-sonic shock loading under dynamic conditions. The study results showed that basalt fiber-reinforced polypropylene (Basalt/PP) composite's tensile and compressive strength is higher than glass fiber-reinforced polypropylene (Glass/PP). The Basalt/PP showed no penetration against low velocity impact (LVI) with negligible deformations till 50 J. However, the Glass/PP perforated at 50 J with various failure patterns occurring at back side. The fiber-matrix interface adhesion plays an important role in super-sonic shock loading by absorbing shock wave energy due to ductile nature of polypropylene and the two composites absorbed energy via matrix and fibers failure, no brittle failure of laminates occurred under shock loading. [ABSTRACT FROM AUTHOR]

This paper presents a study regarding the obtaining, characterizing and mechanically testing a new laminar composite material, consisting of epoxy resin reinforced with basalt plain fabric. The composites were obtained by manual lay-up, cross-link stage being developed by pressure molding in a hydraulic press. Rectangular plates were obtained and cut into samples with specific shapes, for the mechanical tests (tensile, three-point bending and compression). After testing, the fracture zone was analyzed using optical microscopy to observe the behavior of the composite following the mechanical stresses applied (fracture mechanism, voids presence and fiber delamination identification). Due to the low costs and non-hazardous nature, basalt fibers can be a serious competitor in the production of laminar composites that could successfully replace ordinary glass fiber composites. The mechanical properties in tensile, three-point bending, and compression of epoxy-resin-impregnated basalt fiber composites are comparable and even exceed those of widely used epoxy-resin-impregnated fiberglass composites. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Textiles & Engineers / Tekstil ve Mühendis is the property of Union of Chambers of Turkish Engineers & Architects, Chamber of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the real anchorage performance of basalt and glass hybrid fiber reinforced plastic (FRP) anchors in external corrosive environments. In this paper, a combination of experimental studies and finite element analysis was used. By carrying out pull‐out tests of basalt and glass hybrid FRP anchors under the synergistic effect of freeze–thaw cycles and alkaline environment, the effects of factors such as hole diameter, anchorage length, and mortar strength on their anchorage performance and durability were investigated. Critical corrosion time was introduced to determine the degree of corrosion of the anchor rods. After that, it combined with numerical simulation to reveal the degradation mechanism of the anchorage performance of hybrid anchors. The results showed that the best anchorage performance of basalt/glass hybrid FRP anchors was achieved when the hole diameter was 24 mm, the anchorage length was 175 mm, and the mortar strength was 45.5 MPa. The ultimate pull‐out load was up to 122.16 kN. When the time did not exceed the critical corrosion time, the ultimate load‐carrying capacity of basalt and glass hybrid FRP anchors increased by 9.3% compared to the uncorroded environment. Beyond the critical corrosion time, the ultimate load‐carrying capacity was reduced by 23.3% and the anchorage performance was degraded. In addition, the contact interface between the anchor and the mortar is the weak area of the anchoring structure, which should be focused on in the later design of the actual project. Highlights: Basalt/glass hybrid FRP anchors have good corrosion resistance.The anchoring performance of hybrid FRP anchors under the coupled environment is studied.Hole diameter and anchoring length have more influence on the anchor performance.The concept of critical corrosion time is put forward.The failure mechanism and coupling environment influence are revealed by FES. [ABSTRACT FROM AUTHOR]

A growing concern of climate change and waste pollution is causing a shift in products towards green materials. The automotive industry is exploring environmentally friendly alternatives to glass fibers (GF). This research focuses on understanding interactions between constituents of biocomposites made up of basalt fiber (BF) and hemp hurd particle fiber (HF) reinforced polypropylene (PP), and statistically comparing the mechanical properties. The addition of a coupling agent has significantly improved the performance and fiber-matrix interactions in the biocomposite blends. The elastic modulus of some BF/HF/PP mixtures were comparable to the GF/PP composite; however, the GF still outperformed in strength. Rotational and capillary rheometer analysis determined the viscosities of all formulations displaying that basalt composites were consistently lower in viscosity than the glass fiber composite, indicating easier processing conditions. [ABSTRACT FROM AUTHOR]

Recycling concrete with reinforcement made of basalt fibre polymers: investigations on the composite and tensile load‐bearing behaviour The use of recycling concrete is subject to restrictions in Germany, which prevent its use in environmental conditions containing de‐icing salt of exposure classes XD3 and XS3. To overcome these normative barriers, the Munich UAS is conducting research on the use of alternative reinforcement materials that completely eliminate reinforcement corrosion induced by chlorides. In this regard, non‐corrosive fibre composite bars, made of basalt, are employed, which offer ecological advantages over reinforcements made of stainless steel, glass fibre or carbon. The investigations presented here on the composite and tensile load‐bearing behaviour of basalt fibre‐reinforced polymers have arisen as part of a current research project examining the use of this type of reinforcement in bridge caps made of recycling concrete. In addition to preliminary concrete technology studies on the use of up to 100 % recycled aggregates, composite specimens made of recycled concrete and basalt fibre reinforced polymer were tested to provide insights on the load‐bearing behaviour under static and cyclic conditions. [ABSTRACT FROM AUTHOR]

Cemented soil commonly faces issues regarding strength, cracking resistance, and water stability when used in airstrip pavements. Three kinds of soil samples (low-liquid limit clay, high-liquid limit clay, and clayey sand), four kinds of fibers (basalt fiber, glass fiber, fine polypropylene fiber, and coarse polypropylene fiber), and one curing agent (cement) were analyzed in a systematic investigation of the compressive strength of fiber-reinforced cemented soil based on unconfined compressive strength (UCS), water stability, and failure mode. When 38 mm coarse polypropylene fiber at 0.3% content was mixed with 12 mm fine polypropylene fiber at 0.3% content, the hybrid fiber-reinforced cemented soil prepared after 7 d of saturated curing achieved UCS values of 4.18 (low-liquid limit clay), 4.36 (high-liquid limit clay), and 4.16 MPa (clayey sand), which satisfied airstrip requirements for the strength of base course. In this study, coarse polypropylene fiber was adopted and mixed with fine fiber to give full play to their respective advantages and effectively enhance the mechanical properties of cemented soil. The research results improved the understanding of the mechanical properties and reinforcement mechanism of coarse and fine fiber reinforced cemented soil in theory, and enriched the materials and methods of airstrip construction in engineering. [ABSTRACT FROM AUTHOR]

Several researches are going on the hybridization of natural composites by adding SiC as a filler and epoxy due to its higher thermal and physical properties, biodegradable, economic and excellent mechanical properties as compared to synthetic fibers such as glass, Kevlar etc. Jute fiber is an important natural fiber which is abundantly found in India, whereas Basalt fiber is obtained from basalt rock, which is also present in India in a high percentage. Jute fibers are used in geotextiles and agrotextiles for sustainable development in agriculture. The Eco-friendly basalt fibers are used in agriculture and biological applications for soil improvement and fabrication of stucco fireproof netting for animal housings etc. In this paper, basalt and jute fiber reinforced green composites were fabricated using hand layup technique by addition of SiC as filler material in different wt% (0%, 5%, and 10%). The properties of composite material such as impact strength, tensile strength, and flexural strength along with the water absorption test were investigated as per the ASTM standards. Significant improvements were obtained in their mechanical behavior by addition of different wt% of SiC. SEM images showed improved microstructures of green composites with less fractured surfaces at 10% addition of SiC. [ABSTRACT FROM AUTHOR]

Basalt fibres are gaining interest in the fibre-reinforced thermoplastic industries around the world. In this work, basalt and glass short fibres reinforced polypropylene composites were produced using twin-screw extrusion and followed by injection molding. To carry out a comprehensive study on physical and mechanical properties, the composites were produced with different proportions of fibre loadings (for both fibres 5, 10, and 20 wt %). Composites were characterized and studied for tensile (at different strain rates), flexural (at different speeds), impact, dynamic mechanical analysis, density, tensile-relaxation, melt flow index test, and rheometric properties. Results indicate that tensile, flexural, dynamic mechanical analysis, and tensile-relaxation properties increased with increasing fibre proportions in the polypropylene matrix. The melt flow and rheometric behaviors of polypropylene decreased significantly with the addition of short fibres into the matrix. The overall results showed that basalt fibres can be potentially used as replacements for glass fibre to develop these thermoplastic composites. [ABSTRACT FROM AUTHOR]

In this paper, Unsaturated Polyester Resin (UPR) composites with an optimum weight percentage of Basalt fibre(BF), Glass Fibre (GF), Hemp fibre (HF) and hybridization of Basalt with Glass (BG) and with Hemp (BH) and with a varying weight percentage of Nano Silica (0,1,2,3,4,5) were developed using VARI technique. The effects of different fibres, hybridization and percentage of Nano Silica in Mechanical Properties (Tensile, Flexural, Izod Impact and Hardness) and Water absorption characteristics of composites were investigated and discussed. The maximum tensile strength and Tensile Modulus were found for UPR + BF + 2% Nano Silica (316.5 MPa & 11.29 GPa, respectively). The hybrid composites showed intermediate results between the neat fibres composites. It was found that all the mechanical properties were enhanced till 2% Nano Silica loading, and after that, the values started declining. Water absorption behavior was studied till the water uptake percentage attained a constant value, and it was found that equilibrium water uptake decreased till 3% of Nano Silica loading. The fractured surface of the composites was studied for fibre pull out, fibre breakage, interface and uniformity using Scanning Electron Microscopy (SEM). [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the bearing capacity-settlement behavior of strip footing settling on sand soil randomly reinforced with glass fiber, basalt fiber, macromesh fiber, and four different hybrid fiber additives in which these fibers are used together. Model tests were carried out in the laboratory on the strip footing and placed on the unreinforced and reinforced sand with different fibers. In the study, model tests were carried out on seven types of randomly reinforced soils by using glass, basalt, macrame, and mixtures of these fibers as reinforcement. In the model tests, two different fiber contents, 1% and 2%, and two different fiber lengths, 24 mm and 48 mm, were used. Tests were carried out with Dr = 30% and 50% relative density, and reinforcement depths 1B, 2B, and 3B were selected. In addition, the photographs taken during the test were analyzed with the particle image velocimetry (PIV) method and the displacements on the soil were examined. As a result of the reinforced and unreinforced model tests, the highest ultimate bearing capacity was measured as 680 kPa from the tests with Dr = 50% relative density, 48 mm length, 2% contents, and 3B depth macromesh fiber reinforced. In hybrid fibers, the highest ultimate bearing capacity was measured as 495 kPa, with Dr = 50% relative density, 48 mm length, 2% contents, and 2D depth micromesh and basalt fiber-reinforced tests. In the reinforced tests, it was concluded that the most effective fiber on bearing capacity is macromesh fiber. It can be seen that in the PIV analysis, as the fiber additive increased, the settlements made by the foundation decreased under the same pressure. It has also been observed that adding reinforcement to the soil transfers the stresses occurring in the soil to a wider area. [ABSTRACT FROM AUTHOR]

This study aims to analyze strength properties and low-cycle dynamic tests of composite materials modified with glass and basalt fibers. Biopolyamide 4.10 was used as the matrix, and the fiber contents were 15, 30, and 50% by weight. Static tensile tests, impact tests, and determination of mechanical hysteresis loops were carried out as strength tests. The length of the fibers in the produced composites and their processing properties were determined. The composite materials were compared with commercially available glass fiber-reinforced composites with 30 and 50% fiber contents. The results showed that such composites can successfully replace composite materials based on petroleum-based polymeric materials, providing high strength properties and reducing the negative environmental impact by using renewable sources. Composites with 30% basalt fiber composition were characterized by higher tensile strength by about 60% compared to commercially available composites with 30% glass fiber composition and an almost doubly increased Young's modulus. Increasing the content of basalt fibers to 50% results in a further increase in strength properties. Despite the lower tensile strength compared to polyamide 6 with 50% glass fiber content, basalt fibers provided an approximately 10% higher modulus of elasticity. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This present study demonstrates the applicability of basalt fibre-reinforced polymer (BFRP) composite materials in thermal shielding. Basalt fibres are produced from natural, sustainable sources and obtain comparable mechanical performance to commercial glass fibres. In addition to their mechanical strength, BFRPs have excellent chemical and heat resistance. Basalt fibres tend to have a higher thermal stability than their competitor glass fibres. The heat resistance of basalt fibres derives from the volcanic origin of the raw material basalt gabbro. These favourable features make BFRP composites an attractive group of materials for application in several industries. To test the fire resistance of the materials, we produced mono and hybrid composite plates from different types of basalt reinforcement structures (milled fibres, chopped fibres and woven fabric) and epoxy resin. Surface treatment with silane coupling agents significantly improved the mechanical and thermomechanical properties of BFRPs by up to 70%. Three-point bending tests were performed to determine the flexural properties of the composite specimens, and their fire behaviour was evaluated with a horizontal burning test, and a novel jet fire test assisted with infrared thermal imaging. Higher fibre content in hybrid laminates decreased the linear burning rate by 8%, and the maximum surface temperature was approximately 80 °C lower after jet fire impingement compared to woven reinforcement structure. [ABSTRACT FROM AUTHOR]

In this work, basalt fibers (BF) have been investigated as possible natural and sustainable replacements for the common synthetic mineral filler—glass fibers (GF)—used in polyamide 66 matrix (PA66). Composites have been prepared at two different fiber concentrations (15 and 25 wt.%, respectively) by melt blending. The developed systems have been mainly characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), capillary rheology, and scanning electron microscopy (SEM). The kinetic parameters to thermal degradation through the Coats–Redfern method allowed us to attest a negligible effect of fiber type on thermal stability of the developed systems. Composites incorporating 15 wt.% of fiber content possessed the highest activation energy (≥230 kJ/mol). The introduction of BF and GF in PA 66 polymer, regardless of content, always led to an increase in crystallization and melting temperatures, and to a similar reduction in crystallinity degree and glass transition temperature. The shear viscosity of the basic polymer increased by the addition of fillers, particularly at low shear rate, with a pronounced effect in the case of basal fibers. A slightly higher shear thinning behavior of BF/PA66 with respect to GF/PA66 composites was confirmed by fitting the flow curves through the power law model. Finally, a worsening in fiber dispersion, by increasing the content in the matrix, and a weak compatibility between the two phases constituting the materials were highlighted through SEM micrographs. [ABSTRACT FROM AUTHOR]

In this research, the effect of different water aging effect on the crashworthiness of intraply glass/basalt fiber-reinforced composite pipes made using the wet filament winding process was examined. Using both theoretical and practical methods, the water uptake behavior of pipes with winding angles of ±55° and ±70° was examined in the initial section of the investigation. In the later division of this research, crushing tests for composite samples exposed to hydrothermal aging were performed and compared with their dry state. According to the practical results for the water sorption curves, the group that absorbs the most water was non-hybrid basalt fiber reinforced pipes. However, the presence of glass which absorbs water relatively less in hybrid composites, caused basalt fibers to absorb less water in both water types. In quasi-static axial compression experiments, non-hybrid glass pipes exhibited the highest specific energy absorption compared to others. Aging leading to material degradations resulted with decreases in crashworthiness indicators such as energy absorption, load-bearing capability. However, hybridized pipes having more progressive crushing behavior contributed to fixing crushing stability compared to non-hybrid glass fiber reinforced pipes. Also, the increase in the winding angle, whether dry or aged, showed a decrease in the energy absorption values. [Display omitted] • The water type causes different water absorptions in the hydrothermal aging process. • Crushing parameters in terms of load-displacement response, loading characteristics and energy absorption were characterized by quasi-static axial compression tests. • Additionally, the crushing parameters of composite pipes are affected differently by seawater and distilled water. [ABSTRACT FROM AUTHOR]

Cement is an essential material for concrete, which is mostly used worldwide second to the consumption of water. Due to the emission of CO2 into the atmosphere, the alternative material of geopolymer concrete was used. In this research work, silica and alumina content such as ground granulated blast furnace slag (GGBS), fly ash, and triggered by alkali activator solutions were used in geopolymer concrete. Due to the dwindling of river sand, alternative material of manufactured sand (M-Sand) was considered. To avoid corrosion problems in reinforced concrete structures, glass fibre reinforced polymer (GFRP) and basalt fibre-reinforced polymer (BFRP) bars were used as an alternative material for steel reinforcement in this work. As per the code, IS: 10262, the concrete mix design of M30 grade has arrived for the control mix and the same proportion was adopted for geopolymer concrete. Six beams of geopolymer and a concrete control beam of 100 × 160 × 1700 mm were cast and examined under a four-point cyclic load. Cyclic load results were compared with static load under ambient curing. Residual deflection, moment capacity, energy dissipation, and stress–strain behaviour results were compared and discussed. A sudden shear and premature failure were observed in FRP beams under static and cyclic bending tests. [ABSTRACT FROM AUTHOR]

Steel fiber is the most common metal fiber used due to its cost‐effectiveness, high performance, and availability despite its heavyweight. This study is an attempt to evaluate the mechanical properties of steel/glass fiber and steel/basalt fiber‐reinforced epoxy composites. The symmetric hybrid laminates were produced by replacing the innermost 1, 2, 3, and 4 layers of steel fiber (200 mesh size) with basalt and glass fiber layers. The specimens were subjected to tensile, flexural, and Charpy impact tests in accordance with relevant ASTM standards. Moreover, fracture surfaces were analyzed, and the micrographs were obtained using a scanning electron microscope. The results showed that a high improvement in tensile strength was achieved with BS1–E (1 layer steel mesh–8 layers basalt) and GS1–E (1 layer steel mesh–8 layers glass) hybrid composites, with an increase of 528% and 233%, respectively, compared to steel fiber reinforced epoxy composites. Similarly, BS1–E and GS1–E hybrid composites showed the highest flexural strength increase of 82.2% and 66.8%, respectively, compared to steel fiber reinforced epoxy composites. Consequently, the potential to hybridize steel fiber with glass fiber and basalt fiber could create new materials with unique physical structures and synergistic effects on mechanical properties. [ABSTRACT FROM AUTHOR]

Fiber-reinforced soil boasts fewer cracks, higher energy absorption, and higher residual strength. With the well-established concept of carbon neutralization, it is necessary to reduce the dependence on high carbon-emitting reinforcement materials such as cement and concrete. The need for resource recycling has led to the development of reusing construction waste as the raw material for slope and embankment reinforcement. The purpose of this study is to analyze the reinforcement performance and environmental feasibility of glass and basalt fiber on granite residual soil with the content of 3%, 4%, and 5% and the length of 6 mm, 9 mm, and 12 mm. The reinforced samples were subjected to static impact load tests and SEM analysis to study its mechanical properties, microcharacteristics, and structure before and after reinforcement. Results show that the incorporation of 3% glass fibers of 6 mm has the best reinforcement effect on GRS, while the incorporation of 4% basalt fibers of 6 mm also has a good reinforcement ability. Glass fiber performs better than basalt fiber under the optimal content and length. SEM results indicate that glass fibers bind the soil particles more closely, thereby increasing their friction and leading to higher compressive strength. When the length and content of fiber exceed a certain range, the fibers are prone to cross and knot and fail to fill between soil particles, so the fiber and soil particles are separated, which lowers the strength of the soil. It is concluded that both glass fiber and basalt fiber can be well used for reinforcing GRS for higher bearing capacity and fewer cracks at the given proportion and length. Fiber length and content were considered when reinforcing GRS with different fibers in this study. [ABSTRACT FROM AUTHOR]

As basalt fiber has better mechanical properties and stability than glass fiber, cross arms made of continuous basalt-fiber-reinforced epoxy matrix composites are capable of meeting the mechanical requirements in the event of typhoons and broken lines in coastal areas, mountainous areas and other special areas. In this paper, continuous basalt-fiber-reinforced epoxy matrix composites were used to fabricate the core rods and composite cross arms. The results verified that basalt fiber composite cross arms can meet the strict requirements of transmission lines in terms of quality and reliability. In addition to high electrical insulation performance, the flexural modulus and the flexural strength of basalt fiber core rods are 1.8 and 1.06 times those of glass fiber core rods, respectively. Basalt fiber core rods were found to be much better load-bearing components compared to glass fiber core rods. However, the leakage current and the result of scanning electron microscopy (SEM) analysis reveal that the interface bonding strength between basalt fibers and the matrix resin is weak. A 3D reconstruction of micro-CT indicates that the volume of pores inside basalt fiber core rods accounts for 0.0048% of the total volume, which is greater than the 0.0042% of glass fiber rods. Therefore, improving the interface bond between basalt fibers and the resin can further improve the properties of basalt fiber core rods. [ABSTRACT FROM AUTHOR]

Lightweight aggregate concrete (LWC) and fiber reinforced polymer (FRP) reinforcement are potentially more sustainable alternatives to traditional steel-reinforced concrete structures, offering several important benefits. To further the knowledge in this area, the physical–mechanical properties of LWC produced with 0%, 50%, and 100% expanded clay aggregate were assessed. Subsequently, the flexural behavior of LWC beams reinforced with steel reinforcement and glass and basalt FRP bars was tested. The results of the experimental program allowed quantifying of the effect of expanded clay aggregate incorporation on LWC properties. The use of FRP reinforcement was also compared to steel-reinforced concrete beam behavior. The results of this study can provide additional support for the use of innovative materials such as LWA and FRP reinforcement. [ABSTRACT FROM AUTHOR]

The textile-reinforced mortar (TRM) combines high-strength fabric textiles with cementitious mortar matrix to enhance mechanical behaviour and durability, especially at high temperatures. The current study investigated how basalt, carbon, and glass textile grids and TRM composites respond under direct tensile and thermal loading up to 800 ℃. Changes in microstructure were analyzed using scan electron microscopy (SEM), thermo-gravimetric analysis (TGA), and ultrasonic pulse velocity (UPV). The results indicated that temperature significantly affected the coating material and cementitious mortar, weakening the grids and composite specimens. Carbon and glass fibre grids proved more resilient, and the carbon and glass TRM reduced 50% of their ultimate stress at 500 ℃, while for basalt TRM is 200 ℃. A slight gain of strength was observed for all TRM specimens at 300 ℃, and SEM analysis revealed critical changes in the mortar matrix and interfacial transition region. The results were further utilized to calibrate the Gibson model considering humidity and early-stage coating material changes, and yielding results consistent with experimental data. • The thermomechancial tensile behaviour of basalt, carbon, and glass fabric TRM and textiles were presented. • The experimental results were further investigated with the use of a analytical model. • The micro-level experiments were conducted to study the variation under high temperatures. [ABSTRACT FROM AUTHOR]

Basalt fibre is derived from volcanic rocks and has similar mechanical properties as glass fibre. However, poor fibre-matrix compatibility and processing issues are the main factors that have restricted the mechanical performance of basalt fibre-reinforced thermoplastic composites (BFRTP). In this work, basalt continuous fibre composites with polypropylene (PP) and polycarbonate (PC) matrices were studied. The composites were processed by compression moulding, and a processing study was conducted to achieve good quality composites. For the BF-PC composites, the optimisation of material preparation and processing steps allowed the polymer to impregnate the fibres with minimal fibre movements, hence improving impregnation and mechanical properties. For BF-PP composites, a compatibiliser was required to improve fibre-matrix compatibility. The compatibiliser significantly improved the tensile and impact strength values for short BF-PP composites and continued to increase at 40 wt%. Furthermore, the analytical modelling of the Young's moduli indicated that the induced fibre orientation during processing for short BF-PP composites and unidirectional (UD) BF-PC composites had better stress transfer than that of UD BF-PP composites. [ABSTRACT FROM AUTHOR]

Both basalt fibers and glass fibers can be used as reinforced material in fiber-reinforced polymer (FRP) composites. In this paper, the tensile strength, elastic modulus, and hardness of basalt fibers and E-glass fibers are studied by fiber tensile tester and nanoindentation. The crystalline phase and structural feature of fibers are conducted by X-ray diffraction (XRD) and Fourier transform infra-red (FTIR) spectroscopy. The results show that the mechanical properties of basalt fibers are higher than those of E-glass fibers. The density of basalt glasses is higher than that of E-glass and increases with increasing iron content. XRD patterns show that both basalt fibers and E-glass fibers are totally amorphous. Fe3+ mainly exists in the form of [FeO6] in the glass network. It indicates that iron oxide plays a key role in improving the mechanical properties of basalt fibers. [ABSTRACT FROM AUTHOR]

This paper investigates the behaviour of the hybrid fibre, i.e. a combination of E glass and basalt fibre, added in the reinforced concrete column. A total of 6 columns were cast with Conventional Concrete (CC) and Hybrid Fibre Reinforced Concrete (HFRC) to study the structural performance of the column. The concrete was made of cement, manufacturing sand (m-sand), coarse aggregate as major ingredients. In the column, 2% of Basalt fibre along with the E-Glass fibre of 1% were added to the concrete to make the HFRC. Column was tested under universal testing machine with static axial load and deflectometer was placed at the sides of the column to measure the displacement. The axail and laterall deformation of the column was measured using the deflectometer. The strain of the column was determined with the recorded data. The stiffness of the column with respect to the loads was calculated. The lateral buckling of the CC and HFRC columns were calculated and compared. Both CC and HFRC shows a similar mode of failure with the application of the load. The experimental results of the columns were compared with theoretical value and concluded with the performance column with and without fibre added. [ABSTRACT FROM AUTHOR]

In this study, the fresh properties, fracture energy, compressive strength, and flexural strength of self-compacting concrete including glass or basalt fibers were examined, and the effect of fibers on these properties were studied comparatively. For this purpose, fibers having three different lengths (6, 12, and 24 mm) were used in two different contents (2 and 4 kg/m3). The workability of concrete mixtures decreased with fiber addition. The negative effect of basalt fibers on workability was greater than that of the glass fibers. The reduction in flow diameter was up to 40% and 44% as well as the reduction in L-box ratio was up to 41% and 48% in glass and basalt fiber mixtures, respectively. While the fiber addition generally reduced the compressive strength, it increased the flexural strength and fracture energy significantly. Increase in flexural strength was up to 58.6% in glass fiber and 43.5% in basalt fiber mixtures. The fracture energies of glass and basalt fiber mixtures were up to 55.1% and 30.4% higher than that of the control mixture, respectively. [ABSTRACT FROM AUTHOR]

In the present study, the effect of thermal cycling and stacking sequence on the tensile behavior of fiber metal laminate (FML) composites containing glass and basalt fibers was investigated. To fabricate the FML samples, fibers reinforced epoxy composite were sandwiched between two layers of 2024-T3 aluminum alloy sheet. 55 thermal cycles were implemented at a temperature range of 25–115°C for 6 min. The tensile tests were carried out after the thermal cycling procedure, and the results were compared with non-thermal cycling specimens. Scanning electron microscopy (SEM) was employed for the characterization of the damage mechanisms. The FMLs containing four basalt fibers' layers showed higher values of tensile strength, modulus, and energy absorption. On the other hand, the lowest strength and fracture energy were found in the asymmetrically stacked sample containing basalt and glass fibers, due to weak adhesion between composite components (basalt and glass fibers). The lowest tensile modulus was found in the sample containing glass fibers that was due to the low modulus of the glass fibers compared to basalt fibers. In the case of the samples exposed to thermal cycling, the highest and the lowest thermal stabilities were observed in basalt fibers samples and asymmetrically stacked samples, respectively. In accordance with the experimental results, a non-linear damage model using the Weibull function and tensile modulus was employed to predict the stress-strain relationship. The simulated strain–strain curves presented an appropriate agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Geopolymer composites containing refractory, chopped basalt fibers and low‐melting glass were made and systematically heat‐treated at higher temperatures. Potassium‐based geopolymer of stoichiometric composition K2O·Al2O3·4SiO2·11H2O was produced by high shear mixing from fumed silica, deionized water, potassium hydroxide, (i.e., water glass) and metakaolin. With the addition of low‐melting glass (Tm ~815°C) the flexure strengths of the composites increased to ~6 MPa after heat treatment above 900°C to 1100°C. A Weibull statistical analysis was performed showing how the amorphous self‐healing effect of the glass frit significantly improved the flexure strength of the geopolymer and ceramic composites after high‐temperature exposure. At temperatures up to 900°C, the geopolymer‐basalt composite remained amorphous and the low‐melting glass frit flowed into the dehydration cracks in the geopolymer matrix. This type of composite could be described as amorphous self‐healed geopolymer (ASH‐G). At ~1000°C, the geopolymer converted to primarily a crystalline leucite ceramic, but the basalt fiber remained intact, and the melted glass frit flowed and sealed the cracks developed at that temperature. This type of composite could then be described as amorphous self‐healed ceramic (ASH‐C). A temperature of 1150°C was determined to be optimum as at 1200°C the basalt fibers melted and the strength of the reinforcement was lost in the composites. The amorphous self‐healing effect of the glass frit significantly improved the room temperature flexure strength of the heat‐treated geopolymer‐based composites. [ABSTRACT FROM AUTHOR]

Aramid (AF), glass (GF), carbon (CF), basalt (BF), and flax (FF) fibers in the form of fabrics were used to produce the composites by hand-lay up method. The use of fabrics of similar grammage for composites’ manufacturing allowed for a comprehensive comparison of the properties of the final products. The most important task was to prepare a complex setup of mechanical and thermomechanical properties, supplemented by fire behavior analysis, and discuss both characteristics in their application range. The mechanical properties were investigated using tensile and flexural tests, as well as impact strength measurement. The investigation was improved by assessing thermomechanical properties under dynamic deformation conditions (dynamic mechanical–thermal analysis (DMTA)). All products were subjected to a fire test carried out using a cone calorimeter (CC). [ABSTRACT FROM AUTHOR]

An experimental study on tensile, flexural and impact properties of flax-basalt-glass reinforced epoxy hybrid composites is presented in this paper. Test specimens were fabricated by vacuum bagging process. The effects of reinforcement hybridization, fiber relative amounts and stacking sequence on the mechanical properties were investigated. Morphological studies of the fabricated and fractured surfaces through thickness were performed using scanning electron microscopy. Results showed that the developed hybrid composites display enhanced tensile, flexural and impact performance as compared with flax reinforced epoxy composite. The flexural strength increases when partial laminas from flax/epoxy laminate are replaced by basalt/epoxy and/or glass/epoxy laminas. Also, it is realized that incorporating high-strength fibers, i.e. glass or basalt, to the outer layers of the composite leads to higher flexural resistance, whilst the opposite was noticed for tensile properties. The fabricated hybrids were found to have economical and specific mechanical properties benefits. Fiber-relative amounts and stacking sequence have great effects on the mechanical properties. The mechanical properties of hybrid laminates are proven to be highly dependent on the position of the flax layers within the hybrid composite. The Hybridization with basalt and/or glass fibers is an effective method for enhancing the mechanical properties of flax/epoxy composites. [ABSTRACT FROM AUTHOR]

This research article presents the comparative investigation of physical, mechanical, and abrasive wear behavior of chopped glass and basalt fiber‐reinforced epoxy composites. The composites were fabricated by hand lay‐up technique. The fiber (glass and basalt) was varied in the range of 10 to 40 wt.% in the composite at an interval of 10 wt.% to find out the physical (density and void content), mechanical (tensile strength, flexural strength, and impact strength), and steady state abrasive wear rate, respectively. The Taguchi's design of experiment method was used for designing of experimental runs having input controlling variables like sliding distance, normal load, fiber content, and abrasive size. This study clearly demonstrated that with increase the fiber content, the density and void content of both fiber (glass and basalt) reinforced composite were increased. The basalt fiber‐reinforced composites show lesser voids than glass fiber‐reinforced composites. The tensile strength, flexural strength, and impact strength of both composites increased with increase the fiber content whereas glass fiber‐reinforced composites show slightly lower tensile strength, flexural strength, and impact strength than basalt fiber‐reinforced composites. However, as far as basalt fiber‐reinforced composites show better wear resistance than glass fiber‐reinforced composites. [ABSTRACT FROM AUTHOR]

When used as an internal reinforcement, fiber-reinforced-polymer (FRP) composite bars are exposed to a highly alkaline (pH > 12.5) concrete environment. This study evaluated the durability of 24 types of FRP bars in a simulated alkaline concrete environment, specifically with respect to reinforcing-fiber type (carbon, basalt, and glass), fiber sizing, resin chemistry, and manufacturer. A total of 10 types of glass fibers, including two types of E-glass fibers and eight types of electrical corrosion resistance (ECR)-glass fibers, four types of basalt fibers, two types of carbon fibers, six types of resin systems based on vinyl ester, polyurethane, and epoxy resins, and five types of proprietary fiber sizings were used in manufacturing the bars. The study focused on assessing the tensile, transverse-shear, and interlaminar-shear properties of FRP bars subjected to 3 months of accelerated alkaline conditioning at 60°C, as per Canadian Standards Association (CSA) and American Society for Testing and Materials (ASTM) standards. The strength retention and failure of these bars were evaluated as a measurement of the durability and long-term performance of the FRP bars currently available on the market and for quality control by manufacturers. Statistical analysis using independent samples t-test and one-way analysis of variance revealed that the manufacturing parameters have a significant effect on the mechanical characteristics and alkaline resistance of FRP bars. In particular, the results show that the FRP bars manufactured with the same parameters and fiber types but by different fiber manufacturers with different fiber sizings and resin systems produced bars with totally different strength properties and durability performance in an alkaline environment. Vinyl ester resin and silane-sized fiber was the most compatible resin system and produced a more durable glass-FRP bar, while the epoxy resin yielded more durable basalt- and carbon-FRP bars. This paper also describes a procedure for and a criterion of the optimum manufacturing parameters to achieve specific mechanical properties and durability performance with FRP bars. [ABSTRACT FROM AUTHOR]

One of the major drawbacks of fiber reinforced composite laminates is the poor impact damage resistance. Several effective techniques to improve impact damage resistance have been proposed in the literature and among those, fiber hybridization technique takes substantial attention. However, little attention has, as yet, been received for the improvement of impact behavior of basalt fiber reinforced composite laminates by interplyfiber hybridization. The objective of this study is to assess the effect of glass fiber hybridization on Charpy impact behavior of basalt fiber reinforced composite laminates. For this purpose, a series of Charpy impact tests have been performed on composite laminates made of basalt and glass fiber reinforced epoxy resin matrix in five different stacking sequences. Hybrid composite laminates have been fabricated using vacuum assisted resin transfer molding method. The test results show that the absorbed impact energy and impact strength are significantly influenced by the hybridization. [ABSTRACT FROM AUTHOR]

One of the most important fields of research dealing with the use of carbon-, basalt-, and glass-fiber composites in the civil construction industry is their behavior under various chemical exposure conditions. Fiber-reinforced-polymer composites used as internal and external reinforcement in various structural applications can be subjected to widely differing pH situations. This study investigated the chemical durability of various carbon, basalt and glass fibers. The fibers were immersed in four types of solutions with acid, saline, alkaline, and deionized-water conditioning schemes. The fiber mass loss and surface damage along with changes due to chemical reactions were observed through weight-loss measurements and scanning electron microscopy. A criterion was developed to characterize the performance of fibers as very good, good, fair, and poor. This methodology can also be used by manufacturers as a quick quality-control tool for evaluating the chemical resistance of different fibers prior to large-volume production. The results reveal that the carbon fibers exhibited higher chemical resistance than the basalt and glass fibers based on weight loss and evidence of chemical reactions. Moreover, the determination of the fiber chemical composition before and after conditioning in acid and alkaline solutions clearly shows that the E-glass fibers, which are known to contain boron, were very sensitive to chemical corrosion. The ECR-glass fibers showed excellent chemical durability, even better than the basalt fibers. [ABSTRACT FROM AUTHOR]

In the present study the effectiveness of two different biodegradable polymers, namely Polylactic acid (PLA) and ECOVIO (EC), a blend of a copolyester and PLA, as matrix materials for basalt fiber composites, prepared with the "film stacking method" has been investigated. Comparison with composites based on glass fiber mat has also been performed. The addition of basalt fibers, leads to a significant improvement in tensile and flexural strength and stiffness. The ECOVIO/basalt fiber composites exhibited the highest percentage enhancement, while the failure strain decreased dramatically. Therefore, the basalt fabrics appear to have a competitive mechanical performance with the glass fiber mats employed. [ABSTRACT FROM AUTHOR]

[Display omitted] • The current study evaluates the fracture energy of HMA when basalt and glass fibers are used. • The fracture energy of the mixtures was determined via the SCB test method. • The effect of the basalt and glass fibers on the fracture energy of HMA was compared. • The maximum fracture energy was attained from the groups with a 0.50% basalt fiber rate. This paper has focused on the effect of basalt and glass fibers in HMA in terms of crack formation and damage mechanisms. The experimental study was carried out under two stages; i) defining optimum fiber lengths and rates based on Marshall Stability performances using three different fiber lengths (4 mm, 12.5 mm, 22.5 mm) and three different fiber rates (0.75%, 1.00% and 1.5% by weight), ii) examining of fracture tests by using the optimum fiber values (4 mm fiber length and 0.50%, 0.75%, 1.00% fiber content by weight) obtained from the first stage. Fracture energy characteristics of HMA mixtures were examined via Semi-Circular Bending (SCB) test. A total of 24 SCB test specimens from 6 different series, B-0.50, B-0.75, B-1.00, G-0.50, G-0.75, and G-1.00, were used in the experiments. Experimental results were discussed based on some basic physical properties, fracture energy (Gf), dissipated energy (DE), flexibility index (FI), and crack resistance index (CRI) values of HMA mixtures. When 0.50% basalt fiber is utilized in asphalt mixtures, the maximum peak load and Gf value are achieved. Moreover, using 1.00% basalt and 0.75% glass fiber in asphalt mixtures yielded the highest values of FI and CRI, respectively. Nevertheless, when 1.00% glass and 0.75% basalt fiber were added to asphalt mixtures, the minimum values of FI and CRI were obtained, respectively. [ABSTRACT FROM AUTHOR]

Fiber reinforced polymers (FRPs) require a good match of fiber reinforcement and polymer matrix facilitating excellent thermal and mechanical properties. This contribution combines the mineral fibers glass and basalt with a novel silicatic hybrid polymer matrix formed during twin polymerization of 2‐(3‐Amino‐n‐propyl)‐2‐methyl‐4H‐1,3,2‐benzodioxasiline (APSI) as a novel amine hardener and the bisphenol A‐based epoxide BADGE. The resulting ternary hybrid material consists of a nanostructured and crosslinked epoxide, phenolic resin and polydialkylsiloxane network. In comparison to conventionally cured BADGE with IPDA (isophorone diamine), the glass and basalt fiber reinforced twin polymers showed a retarded combustion with a higher residual mass after oxidation. Moreover, the reinforcing effect with glass respective basalt was pronounced in case of APSI cured BADGE. The increased inorganic ratio in the composites due to in situ formation of polysiloxane species seems to affect beneficially FRPs thermal and mechanical properties by increasing the stiffness by 25% and the storage modulus by 260%. POLYM. COMPOS., 40:3115–3121, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

• The sample which has the largest permeability, had the minimum value of draindown. • The effect of glass fiber in reducing the permeability is far greater than that of the basalt. • The tensile strength of asphalt mixtures increases by adding fiber. • The effect of nano-silica in reducing abrasion and reduction of sensitivity to oxidation is considerable. Open-graded friction course (OGFC) is a mixture having gap graded aggregate which is used in pavement surfacing. Asphalt mixtures were modified by Nano silica, polymer, basalt fiber and glass fiber. A draindown test, Cantabro test, permeability test and an indirect tensile strength test and moisture susceptibility were used to evaluate the performance of OGFC mixtures. Test results revealed optimum compounds for 0.2% basalt fiber with 2% nano-silica and 4.5% Styrene-Butadiene Styrene (SBS) Polymer. The minimum air voids content of fiber-reinforced OGFC mixtures modified with nanomaterial should be 13% for 6% bitumen. The results showed the effect of nano-silica in reducing abrasion and reduction of sensitivity to oxidation is considerable and the effect of basalt fiber per 0.2% in the asphalt mixture to be greater than that of glass fiber in reducing the draindown phenomenon; and for controlling the level of draindown phenomenon, nano-silica compound should also be used with basalt fiber. It was also found that although the use of basalt fiber is more effective in decreasing draindown in comparison with glass fiber, the effect of glass fiber in reducing the permeability of the asphalt mixture is far greater than basalt fiber. [ABSTRACT FROM AUTHOR]

Abstract This research investigates experimentally and analytically a novel one-way slab system reinforced with either basalt fiber-reinforced polymer (BFRP) or glass fiber-reinforced polymer (GFRP) longitudinal bars embedded in fiber-reinforced concrete (FRC) incorporating basalt macro-fibers (BMF). Twelve one-way concrete slab strips were prepared and tested to failure under four-point loading configuration. The investigated parameters included the type of fiber-reinforced polymer bars (BFRP and GFRP), the longitudinal reinforcement ratio ρ f (1.4 and 2.8 ρ bf , where ρ bf is the balanced reinforcement ratio), and the volume fraction of the fibers added (0, 0.5, 1, and 2% per volume). The test results demonstrated the promise of BMF to enhance the flexural performance of the tested slab strips in terms of ductility and load-carrying capacities. The formulations of different available codes and design guidelines were used to predict the test results. Comparison between the experimental and predicted results showed the adequacy of the models to predict the flexural performance of the tested slab strips. The findings of this study demonstrated the potential of using the BMF as alternatives to conventional fibers in flexural concrete members. [ABSTRACT FROM AUTHOR]

• Experimental analysis to study the thermal properties of basalt composites. • In-depth thermal diffusivity measurements by pulse thermography. • In-plane thermal diffusivity by space resolved method. In recent years, there is a great demand for ecofriendly, light weight and cost effective composites. Basalt fiber is one such naturally available fiber which offers exceptional properties over glass fibers. In this study a Basalt fiber reinforced composites were fabricated by vacuum bagging technique. Thermal properties of these composites were determined using infrared thermography. In-depth and in-plane thermal diffusivity were determined by using pulse thermography and space resolve method, respectively. The in-plane thermal diffusivity was determined in the transmission and reflection modes. In-depth thermal diffusivity was validated with Light flash method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fiber hybridization technique was used to improve performance of recycled concrete. • Multicriteria analysis was used to rank performance of single and hybrid fiber MRC. • MRC-0.5BF0.5GF showed the highest strength improvement and freeze–thaw resistance. • MRC prepared with BF only had the highest net cost increase (121.7%) of all mixes. Fiber hybridization is a new and effective way of altering the inherent low mechanical properties and durability issues of recycled concrete by using a multi-fiber approach. Research conducted thus far is majorly focused on studying the effects of hybrid fibers on the basic mechanical properties of recycled concrete and no attention is given to the multicriteria-based performance assessment, which is highly important from the perspective of practical applications. The current study is an effort in this regard that intends to evaluate, compare, and rate the multicriteria-based performance of a total of eleven mix formulations prepared with a single and hybrid usage of basalt fiber (BF), polypropylene fiber (PPF) and glass fiber (GF). In addition, two mineral admixtures namely pulverized flyash (PFA) and ground granulated blast furnace slag (GGBFS) were used. From the results of mechanical properties, it is determined that mix formulations comprising hybrid 0.75 %BF-0.25 %PPF and 0.5 %BF-0.5 %GF had the highest strength improvement of 16–21% in compressive strength, 36–49% in splitting tensile strength, and 54–71% in flexural strength. The freeze–thaw assessment revealed that the use of hybrid fibers together with PFA and GGBFS resulted in superior durability performance of recycled concrete specifically in terms of lower length variation (0.055%), lower mass loss (0.39%) and higher UPV (4137 m/s) after 300 cycles. From the cost analysis, it is observed that MRC-1BF had the highest net cost increase of 121.7% of all mixes. Lastly, the multicriteria analysis revealed that the hybrid BF-GF and BF-PPF based MRC had the best performance score and ranking of all formulations, thus implying that their practical use would be highly beneficial in terms of mechanical performance as well as cost-effectiveness. [ABSTRACT FROM AUTHOR]

In this paper, the effect of salt-fog exposition on the mechanical behavior of sandwich panels having cork agglomerate core was investigated. In particular, the aim of this research work is to assess the shield function of unidirectional basalt and E-glass reinforced polymer on the aging and failure mechanism of the core when such class of material are destined to operate in hostile environments (e.g., marine environment). To do this, the manufactured sandwich panels were exposed up to 60 days to salt-fog environment, according to ASTM B 117 standard. Unaged and aged specimens were analyzed through three point bending tests after aging time of 10, 25 and 60 days. Digital Image Correlation (DIC) was carried out to perform a strain field analysis of the longitudinal cross-sections. The differences in the mechanical behavior of the synergistic cooperation of the cork core with basalt and glass fiber were highlighted thorough this technique. Moreover, the failure mechanisms related to each combinations for different aging times were described. The experimental results showed that, the intrinsic conditions of the composites (e.g., presence of defects, poor fiber-matrix adhesion), that are strictly linked to the fiber-matrix compatibility and to the impregnation quality, may induce to differences in the local mechanical behavior of the sandwich panels and to a faster aging process of the cork core in the case of basalt fiber skinned sandwich, especially in the first phases of the exposition. [ABSTRACT FROM AUTHOR]

Recently, in responding to the resource shortage and steel corrosion, the combination of seawater and sea sand concrete (SWSSC) and fibre reinforced polymer (FRP) bars was proposed to replace the traditional reinforced concrete structures in civil engineering. For FRP bars in the real service condition of concrete structure, the synergistic effect of sustained load and corrosion environment needs to be considered. This paper presents an investigation on the durability of basalt- and glass-fibre reinforced polymer bars exposed to a SWSSC environment under different sustained stress levels. Scanning electron microscopy was employed to study the degradation mechanism of FRP bars. [ABSTRACT FROM AUTHOR]

Interfacial adhesion of basalt and glass fibre reinforced polypropylene composites was studied using microdebond testing technique. A focus was put on a simple approach of applying extruded thermoplastic films as a matrix material for microdroplet formation. The ability of different viscosity and thickness polypropylene films to form symmetrical droplets under a temperature range of 200–240℃ was evaluated. Emphasis was put on polypropylene matrix chemistry, silane fibre surface treatment and testing loading rate impact on interfacial performance change in polypropylene-basalt fibre and polypropylene-glass fibre microcomposites. It was found that it was possible to obtain high symmetrical droplet yield out of polypropylene films of melt flow rate 50 and 125 g/10 min and 55–85 µm thickness at 240℃. The presence of maleic anhydride grafted polypropylene coupling agent increased the interfacial shear strength significantly. Microcomposites with glass fibre had higher interfacial shear strength in comparison with the used basalt fibre, mainly due to the difference in their sizing. Various silane-based fibre surface coatings did not result in significant interfacial adhesion changes. Polypropylene-glass fibre microcomposite interfacial shear strength at 0.5, 3.0 and 10.0 mm min–1 loading rates had similar values with high maximum pull-out force scatter at 0.5 and 3.0 mm min–1 loading rates and low scatter at 10.0 mm min–1. [ABSTRACT FROM AUTHOR]