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Intra-ply hybridization of two different braided yarns can enhance flexural and shear strength compared to conventional yarn properties. Hybrid braids offer the potential to reduce costs and boost industrial productivity. An impregnated textile with resin coating exhibits more cohesive behavior, ensuring stress distribution throughout the yarns and preventing a reduction in the composite’s ultimate tensile capacity due to telescopic failure. This study aimed to develop new coated hybrid braided textiles made from sisal/PET for reinforcement employment in cementitious composites and to evaluate their bonding effect with the matrix through pullout tests. Materials were selected for tensile strength properties, thickness, and bonding characteristics. The braided fibers were chosen based on their strength and elongation (549N and 29.2%) and diameter (2.41 mm). They were coated with green epoxy resin and subjected to the pullout method for further evaluation. The results indicated that the best sample of the developed sisal/PET braided textile comprised 43% sisal and 57% PET, due to its higher elongation (29.17%), tenacity (216 cN/Tex), and tensile strength (549 N). The pullout properties demonstrated high energy absorption, reaching 2100.0 N.mm, which is 2.8 times higher than steel, exhibiting a pseudo-ductile behavior. This indicates its potential for use in cementitious composite reinforcement. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymers (FRPs), which are resistant to corrosion, are used as reinforcement material for concrete. However, the flexural behavior of concrete members reinforced with FRPs can vary depending on the properties of FRPs. In this study, the flexural behavior of one-way concrete slab specimens reinforced with a new grid-type carbon-fiber-reinforced polymer (CFRP) (carbon grid) manufactured by bonding pultruded CFRP strands to an adhesive was investigated. The experimental results indicated differences in the load–deflection relationships of the specimens depending on the carbon grid reinforcement amount. Specimens in which the carbon grids were over-reinforced or reinforced close to the balanced reinforcement ratio reached the maximum load due to concrete crushing and exhibited ductile failure. The specimen under-reinforced with the carbon grid exhibited brittle failure. Specimens with carbon grid reinforcement close to a balanced reinforcement ratio exhibited maximum loads ranging from 0.43 to 0.61 times the calculated flexural strength, which resulted in becoming 0.86–1.00 lower in the specimens with a wider width of the CFRP strands. This study proposes coefficients to estimate the stiffness of carbon-grid-reinforced concrete flexural members after cracking. Applying these coefficients resulted in stiffness calculations that reasonably simulated the behavior of the specimens reinforced with carbon grids after crack formation. [ABSTRACT FROM AUTHOR]

As a high-performance composite material in construction, textile-reinforced concrete has been of interest in recent years. This study significantly contributes to the characterization of textile-reinforced concrete through an extensive experimental and analytical investigation, focusing on impregnated textile-reinforced concrete under flexural loading. For this purpose, two sets of experiments were conducted. The first set involved model input parameters tests, including the tensile test of epoxy resin and E-glass yarn, as well as the compression and flexural tests of concrete. The second set is related to validation tests, specifically focused on the flexural behavior of textile-reinforced concrete. Micromechanical frameworks were employed to model the flexural behavior of textile-reinforced concrete and a multiscale micromechanical model based on the classical lamination theory was developed to predict the load-deflection diagram of textile-reinforced concrete in the three-point bending test setup. The modeling results demonstrated a remarkable agreement between predictions and experimental data. Key performance indicators, including the first crack force, ultimate force, flexural modulus, and maximum deflection, were accurately predicted with errors of 2.4%, 6.1%, 11.1%, and 6.3%, respectively. Furthermore, from a parametric study, it is perceived that the flexural modulus of elasticity in textile-reinforced concrete is predominantly influenced by concrete properties, while the ultimate strength of textile-reinforced concrete is significantly affected by the properties of the impregnated fabric. [ABSTRACT FROM AUTHOR]

Textile-reinforced concrete (TRC) is a composite concrete material that utilizes textile reinforcement in place of steel reinforcement. In this paper, the efficacy of the partial replacement of steel reinforcement with textile reinforcement as a technique to boost the flexural strength of reinforced concrete (RC) beams was experimentally investigated. To increase the tensile strength of concrete, epoxy-coated carbon textile fabric was used as a reinforcing material alongside steel reinforcement. Beams were cast by partially replacing the steel reinforcement with carbon fabric. Partially replaced carbon fabric-reinforced concrete beams of size 1000 × 100 × 150 mm3 were cast by placing the fabrics in different layers. A four-point bending test was used to test cast beams as simply supported until failure. Then, 120 ohm strain gauges were used to study the stress–strain behavior of the control and TRC beams. Based on this experimental study, it was observed that 50% and 25% of the steel replaced with carbon fabric beams performed better than the conventional beam. ABAQUS software was used for numerical investigation. For the load deflection characteristics, a good agreement was found between the experimental and numerical results. Based on the experimental analysis carried out, a prediction model to determine the ultimate load-carrying capacity of TRC beams was created using an Artificial Neural Network (ANN). [ABSTRACT FROM AUTHOR]

Over the past decade, the textile-reinforced concrete (TRC) composite was gradually used to replace the fibre-reinforced polymer in the strengthening or repairing of existing reinforced-concrete structures, thanks to many criteria of sustainable development. The reinforcement ratio of textiles within TRC composites emerges as a crucial factor significantly impacting their reinforcement effectiveness, altering the material’s mechanical behaviour and properties. This study presents both experimental and numerical findings concerning the tensile behaviour of carbon TRC composites, exploring reinforcement ratios ranging from 0.5 to 1.5%. As experimental results, the carbon TRC specimens exhibited a strain-hardening behaviour with the cracking phase. The ultimate strength improved by 95 and 146% compared to that of non-reinforced specimens, respectively, with the reinforcement ratio of 0.92 and 1.32%. As numerical results, the model reached the strain-hardening curve with three distinct phases when the reinforcement ratio was higher than a critical value (0.7%). The effect of reinforcement ratio ranging from 0.5 to 1.5% on the mechanical behaviour and properties of carbon TRC was also highlighted and analysed.

Development of a wrapping process for building components made of glassfiber and textile‐reinforced concrete In the research project WiFaPu (wrapping process for highly fiber‐reinforced concrete using the example of a pump sump), a wrapping process was developed that combines the advantages of glassfiber‐reinforced concrete and textile‐reinforced concrete in terms of manufacturing processes and composite load‐bearing behavior. In the developed process, the fine‐grained concrete together with blown in short fibers is sprayed on a carrier sheet as well as on the textile reinforcement to produce a thin glassfiber and textile‐reinforced concrete layer of defined thickness, which is wrapped up in a quasi‐continuous process to form a component of any cross‐sectional thickness. The article reports on the challenges in the development of the wrapping process and the associated coordination of the material components in order to produce durable components with simple geometries, acceptable surfaces and a reduced CO2 footprint. Pump sumps are produced as demonstrator components of the process and their load‐bearing capacity and suitability for use are analyzed. According to the experimental load tests of critical component areas, components with a high load‐bearing capacity are produced. Filling tests show that serviceable pump sumps can be produced using the wrapping process. The overall high water impermeability of the thin‐walled components is made possible by fine‐grained concrete with low water penetration depth and very small crack widths with high self‐healing potential. [ABSTRACT FROM AUTHOR]

Textile-reinforced concrete (TRC) has gained a lot of attraction in recent years. Adequate bond between the phases in this system allows to transfer high loadings, thus enabling high performance. The terminus textile reinforcement, however, comprises many different types of fabrics, which differ in their chemical composition, geometry, surface properties etc., and thus exhibit substantially different bond properties. In the course of RILEM’s Technical Committee 292 work on TRC it was found that a comprehensive understanding of the complex interactions between individual parameters is still lacking. This is amplified by the fact that different types of textile reinforcement are preferably used in different regions of the world. This paper therefore attempts to compile findings from literature on the bond in TRC. The database used was created in the course of the TC work. Additional papers of relevance were identified by scanning scientific web databases. The different influencing parameters are given in this paper in a hierarchical order, starting from the level of the individual constituents (filament and matrix) to impregnated fabrics and the influence of textile manufacturing and architecture on the bond. Finally, by mapping all the cited literature used in this paper based on grouped keywords the complex intercorrelations are visualised. [ABSTRACT FROM AUTHOR]

To examine the flexural toughness characteristics of textile-reinforced lightweight aggregate concrete (TRLC), a four-point bending test was conducted to assess the impact of varying numbers of textile layers and the inclusion of hydroxypropyl methylcellulose on the ultimate load-bearing capacity and deformation capacity of TRLC thin plates. Six groups of specimens were prepared for the experiment, and the bending capacity of the thin plates in each group was evaluated. The flexural toughness index was utilized to quantify the bending performance of TRLC thin plates. The findings revealed that increasing the number of textile layers improved the initial cracking load, initial cracking deflection, ultimate load, ductility, and flexural toughness of the thin plates. For the specimens without HPMC, the initial cracking load was increased by up to 36.1%, the ultimate load by up to 40.9%, and the flexural toughness index by up to 292% as the number of textile layers was increased. For specimens doped with HPMC, the initial cracking load was increased by up to 61.7%, the ultimate load by up to 246.7%, and the flexural toughness index by up to 65%. The TRLC thin plate containing hydroxypropyl methylcellulose exhibited a reduced initial cracking load yet displayed a stronger matrix consistency and good flexural toughness. Moreover, the enhancement in the ultimate load of TRLC thin plates with hydroxypropyl methylcellulose was more pronounced with an increased number of textile layers, resulting in a significantly higher number of cracks compared to TRLC without hydroxypropyl methylcellulose and an 11.40-fold increase in the flexural toughness index. [ABSTRACT FROM AUTHOR]

In the case of solid slabs made of reinforced concrete that are usually subjected to bending, large areas of the structure are stressed well below their load-bearing capacity. Contrary to this are shell structures, which can bridge large spans with little material if designed according to the force flow. To improve the efficiency of ceiling slabs, we want to utilize the shell load-bearing behavior on a smaller scale by resolving the solid interior accordingly. In order to study a wide range of such constructions virtually, a parametric multi-objective simulation environment is being developed in an ongoing research project. The basic analysis approaches that were implemented are presented in this paper. The basic workflow, the used programs and material models, and their calibration on the tests on textile-reinforced concrete (TRC) samples are described.

In recent years, the use of natural flax fibres as a reinforcement in composite building structures has witnessed a growing interest amongst research communities due to their green, economical, and capable mechanical properties. Most of the previous investigations on the load-bearing behaviour of concrete components reinforced with natural flax fibres include inorganic impregnations (or even no impregnation) and exclude the use of textile fabrics. Also, the mechanical behaviour of textiles made of natural flax fibres produced as leno fabrics remains to be investigated. In this paper, the results of tensile tests on concrete components reinforced with bio-based impregnated leno fabrics are presented. For comparison, multilayer non-impregnated and impregnated textiles were considered. The results demonstrated that reinforced textiles yielded an increase in the failure loads compared to the concrete cross-sections without reinforcement. The stress-strain diagrams showed that the curves can be divided into three sections, which are typical for reinforced tensile test specimens. For the impregnated textiles, a narrowly distributed crack pattern was observed. The results showed that impregnated textiles tend to support higher failure stresses with less strains than non-impregnated textiles. Moreover, an increase in the reinforcement ratio alongside larger opening widths of the warp yarns enables higher failure loads. [ABSTRACT FROM AUTHOR]

In this study, the flexural bearing behavior of corroded reinforced concrete (RC) beams reinforced with U-type Textile Reinforced Concrete (TRC) was investigated using a four-point bending loading method. Nine test beams were produced: one original beam, three RC beams with corrosion alone, and five corroded beams strengthened with U-type TRC. The analysis focuses on assessing the impacts of the steel corrosion degree and the number of textile layers on various aspects of the bending behavior, such as failure modes, bearing capacity, and load displacement curves, in U-type TRC-strengthened corroded beams. The experimental results revealed three distinct failure modes in the U-type TRC-strengthened corroded beams. TRC effectively enhanced the bearing capacity. With sufficient textile layers, it can be restored to the level of the original RC beams. Moreover, in the cases of severe corrosion in RC beams, the bearing capacity increased more significantly. The TRC also enhanced the ductility. Finally, a calculation equation for the ultimate bearing capacity of U-type TRC-strengthened corroded beams was presented and validated, demonstrating consistent alignment with the experimental data. [ABSTRACT FROM AUTHOR]

In the case of solid slabs made of reinforced concrete that are usually subjected to bending, large areas of the structure are stressed well below their load-bearing capacity. Contrary to this are shell structures, which can bridge large spans with little material if designed according to the force flow. To improve the efficiency of ceiling slabs, we want to utilize the shell load-bearing behavior on a smaller scale by resolving the solid interior accordingly. In order to study a wide range of such constructions virtually, a parametric multi-objective simulation environment is being developed in an ongoing research project. The basic analysis approaches that were implemented are presented in this paper. The basic workflow, the used programs and material models, and their calibration on the tests on textile-reinforced concrete (TRC) samples are described. [ABSTRACT FROM AUTHOR]

Textile-reinforced concrete not only has many advantages that lead to less consumption of primary resources, but also enables the creation of thin and subtle elements. The high performance of such elements allows us to create interesting architectural features, such as translucent concrete. This article focusses on the possibility of reinforcing translucent concrete panels.

Textile-reinforced concrete (TRC) is a composite material consisting of a concrete matrix with a high-performance reinforcement made of technical textiles. TRC offers unique mechanical properties for the construction industry, enabling the construction of lightweight, material-minimized structures with high load-bearing potential. In addition, compared with traditional concrete design, TRC offers unique possibilities to realize free-form, double-curved structures. After more than 20 years of research, TRC is increasingly entering the market, with several demonstrator elements and buildings completed and initial commercialization successfully finished. Nevertheless, research into this highly topical area is still ongoing. In this paper, the authors give an overview of the current and future trends in the research and application of textiles in concrete construction applications. These trends include topics such as maximizing the textile utilization rate by improving the mechanical load-bearing performance (e.g., by adapting bond behavior), increasing design freedom by utilizing novel manufacturing methods (e.g., based on robotics), adding further value to textile reinforcements by the integration of additional functions in smart textile solutions (e.g., in textile sensors), and research into increasing the sustainability of TRC (e.g., using recycled fibers).

Textile-reinforced concrete not only has many advantages that lead to less consumption of primary resources, but also enables the creation of thin and subtle elements. The high performance of such elements allows us to create interesting architectural features, such as translucent concrete. This article focusses on the possibility of reinforcing translucent concrete panels. [ABSTRACT FROM AUTHOR]

Textile-reinforced concrete (TRC) is a composite concrete material that utilizes textile reinforcement in place of steel reinforcement. In this paper, the efficacy of the partial replacement of steel reinforcement with textile reinforcement as a technique to boost the flexural strength of reinforced concrete (RC) beams was experimentally investigated. To increase the tensile strength of concrete, epoxy-coated carbon textile fabric was used as a reinforcing material alongside steel reinforcement. Beams were cast by partially replacing the steel reinforcement with carbon fabric. Partially replaced carbon fabric-reinforced concrete beams of size 1000 × 100 × 150 mm3 were cast by placing the fabrics in different layers. A four-point bending test was used to test cast beams as simply supported until failure. Then, 120 ohm strain gauges were used to study the stress–strain behavior of the control and TRC beams. Based on this experimental study, it was observed that 50% and 25% of the steel replaced with carbon fabric beams performed better than the conventional beam. ABAQUS software was used for numerical investigation. For the load deflection characteristics, a good agreement was found between the experimental and numerical results. Based on the experimental analysis carried out, a prediction model to determine the ultimate load-carrying capacity of TRC beams was created using an Artificial Neural Network (ANN).

The flexural behavior of corroded reinforced concrete (RC) beams strengthened with textile reinforced concrete (TRC) was analyzed and discussed in this work. Thirteen beams, including one reference beam, three corrosion-only beams, and nine TRC-strengthened corroded beams, were tested under four-point bending. The failure modes, cracks, bearing capacity, load–displacement curves and ductility of the tested beams were analyzed. The results showed that the TRC played a role in increasing the number of cracks and decreasing the width of the cracks in the corroded RC beams. In terms of improving the bearing capacity, TRC can improve the bearing capacity of corroded beams even more than the reference beams, and the strengthening after removing the concrete cover of corroded RC beams is better than direct strengthening. The corroded beams after TRC strengthening exhibited improved ductility. The energy absorption index of the TRC-strengthened corroded RC beams increased with the increase in the number of textile layers. [ABSTRACT FROM AUTHOR]

Textile-reinforced concrete (TRC) is a composite material consisting of a concrete matrix with a high-performance reinforcement made of technical textiles. TRC offers unique mechanical properties for the construction industry, enabling the construction of lightweight, material-minimized structures with high load-bearing potential. In addition, compared with traditional concrete design, TRC offers unique possibilities to realize free-form, double-curved structures. After more than 20 years of research, TRC is increasingly entering the market, with several demonstrator elements and buildings completed and initial commercialization successfully finished. Nevertheless, research into this highly topical area is still ongoing. In this paper, the authors give an overview of the current and future trends in the research and application of textiles in concrete construction applications. These trends include topics such as maximizing the textile utilization rate by improving the mechanical load-bearing performance (e.g., by adapting bond behavior), increasing design freedom by utilizing novel manufacturing methods (e.g., based on robotics), adding further value to textile reinforcements by the integration of additional functions in smart textile solutions (e.g., in textile sensors), and research into increasing the sustainability of TRC (e.g., using recycled fibers). [ABSTRACT FROM AUTHOR]

Of all industrial sectors, the construction industry accounts for about 37% of carbon dioxide (CO2) emissions. This encompasses the complete life cycle of buildings, from the construction phase to service life to component disposal. The main source of emissions of climate-damaging greenhouse gases such as CO2, with a share of 9% of global emissions, is the production of ordinary cement as the main binder of concrete. The use of innovative approaches such as impregnated carbon yarns as non-corrosive reinforcement embedded in concrete has the potential to dramatically reduce the amount of concrete required in construction, since no excessive concrete cover is needed to protect against corrosion, as is the case with steel reinforcement. At the same time, architectural design options are expanded via this approach. This is achieved above all using novel robotic manufacturing technologies to enable no-cut direct fiber placement. This innovative technological approach to fabricating 2D and 3D biologically inspired textiles, including non-metallic structures for textile-reinforced concrete (TRC) components, will promote an automatable construction method that reduces greenhouse gas emissions. Furthermore, the impregnated yarn which is fabricated enables the production of load-adapted and gradual non-metallic reinforcement components. Novel and improved design strategies with innovative reinforcement patterns allow the full mechanical potential of TRC to be realized. The development of a robotic fabrication technology has gone beyond the state of the art to implement spatially branched, biologically inspired 3D non-metallic reinforcement structures. A combined robotic fabrication technology, based on the developed flexible 3D yarn-guiding and impregnation module and a 3D yarn fixation module, is required to implement this sophisticated approach to fabricate freely formed 3D non-metallic reinforcement structures. This paper presents an overview of the development process of the innovative technological concept. [ABSTRACT FROM AUTHOR]

Textile-reinforced concrete (TRC) is a composite made with bi-directional non-metallic fabric embedded in a fine-grained cementitious matrix. When engineered appropriately, these composites can reduce material usage for the desired performance, resulting in slimmer sections and enhanced material efficiency, which in turn lowers the CO2 footprint. To facilitate the widespread application of TRC in practice, it is crucial to comprehend the material and structural behavior of these composites, which can pave the way toward an optimized design methodology. In this paper, the tensile response of TRC is studied with different textile geometries, volume fractions and matrix strengths. The influence of the coating impregnation on the effectiveness of the textile to enhance the response of the composite is discussed, with complementing evidence from microstructural observations. The results of tests with different textile configurations indicate a transition in the type of stress–strain response from tri-linear to bi-linear, beyond a certain effective volume fraction. The paper also presents a simplified model to predict the bi-linear response from the efficiency factor-based approach. The insights gained can assist in achieving composite designs with optimized sections and limited tensile stress cracking, ensuring the targeted performance in slender elements. [ABSTRACT FROM AUTHOR]

Thin-walled concrete structures with textile reinforcement have a number of advantages over conventional reinforced concrete. This article discusses the manufacturing method and investigates the structural behavior of the arch made of textile-reinforced concrete (TRC). The possibility of manufacturing an experimental arched structure with textile reinforcement is demonstrated. This study includes the arch design, mold preparation and loading test. With the use of a 3D printer, the mold of the arched structure was printed, which made it possible to implement a distributed loading scheme. Three concrete arches including a reference non-reinforced arch and two concrete arches reinforced with glass textiles were designed and tested. The test results showed a slight increase in the strength of the reinforced arch compared to the control non-reinforced arch. The effectiveness of the reinforcement of the arch structure amounts to about 10 % increase in contrast to arches with external reinforcement, where the increase in strength reaches 40–85 %. However, the main advantage of such reinforcement is the significant residual strength of the arch structure, which prevents catastrophic collapse of it. The textile reinforcement continued to hold the failed concrete matrix in contrast to the external reinforcement, where the loss of cohesion leading to delamination could cause the fracture of parts of the concrete.

In this article, a partial selection of experiments on enhancing the impact resistance of structural components with non-metallic, textile-reinforced concrete is discussed. The focus is on the experimental investigations in which the impact resistance of thin, textile-reinforced concrete plates is characterized. The article discusses the materials, fabrics and test setup used. For the experimental work, a drop tower from the Otto Mohr Laboratory, which belongs to the Technische Universtät Dresden, was used. Furthermore, the experimental results are presented and evaluated using different methods. Based on the collected data, a suitable approach to determining the perforation velocity of an impactor through the investigated thin, textile-reinforced concrete plates is shown. [ABSTRACT FROM AUTHOR]

This paper describes a work that examines a new solution to the problem that arises from the relatively high amount of transverse reinforcement required in HSC columns. It presents an alternative to common transverse steel reinforcement, a dual system comprising steel ties and a carbon-fiber mesh (CFM) applied internally together with steel ties. The behavior of the proposed system was examined in this work in a series of twelve laboratory tests of circular stub column specimens. The experiments performed in this work focused on the columns' load and displacement capacities. The tests were planned with the aid of an analytical model that was originally developed for a hybrid system of external fiber-reinforced polymer (FRP) sheets and internal steel, and was adapted for the current system. An analysis of the results shows that for a given amount of conventional transverse steel, the application of the carbon-fiber meshes adds efficiency to the rebar confinement system, in terms of both the load bearing capacity and the ductility, and for specimens with the hybrid confinement system, the higher the carbon fiber amount the larger the ductility improvement. Furthermore, fair to good agreement was observed between the model and the measured stress–strain curves, especially those of the peak stresses. Based on the above findings and the added benefit of fire resistance, the hybrid method appears to be promising for confining HSC columns. [ABSTRACT FROM AUTHOR]

Thin‐walled textile‐reinforced concrete beams have recently emerged as a promising approach for material‐efficient design. However, the increased complexity of the formwork is a major challenge in implementing such elements for broader use in the construction industry. This study presents a novel type of stay‐in‐place flexible formworks with integrated textile reinforcement. The use of weft‐knitted textiles allows the integration of continuous high‐strength rovings as shear reinforcement and the introduction of spatial features within the fabric to guide bending‐active rods to shape the complex cross‐section geometry. The manufacturing procedure and the structural performance were investigated in an experimental campaign consisting of four concrete beams with I‐profile cross sections tested in three‐point bending, where aramid rovings were used for the shear and conventional deformed steel bars for the flexural reinforcement. The transverse reinforcement ratio proved to be essential in increasing the shear strength. Thereby, the use of digital image correlation measurements of the surface deformations allowed the direct assessment of the strains and, thus, the mechanical activation of the textile reinforcement. The full tensile capacity of all the aramid rovings crossing the governing crack could not be exploited due to the brittle material behavior, resulting in a progressive failure once the first roving reached its tensile strength. Compatibility‐based stress fields were used to predict the load‐deformation and failure behavior of the tested beams, which resulted in an excellent agreement of the ultimate loads and failure modes obtained from the model with the observations and results from the experiments. [ABSTRACT FROM AUTHOR]

This work focused on material and Global Warming Potential (GWP) savings for the construction of textile-reinforced concrete (TRC) beams made of carbon fabrics (without steel rebars), which were characterized by their flexural behavior. Two beam design approaches were explored for material and GWP savings: (1) regular TRC beam designs, in which the steel rebars were replaced by a carbon textile, which eliminated the need for a thick concrete protective layer that is required in steel reinforcement; and (2) optimized truss-like TRC beams that were based on topology optimization, which distributed the concrete and fabric at their optimal locations. The aim was to minimize concrete consumption through the development of lightweight structural concrete elements with irregular shapes. This exploited the ability of the fabrics to conform to complex shapes and their corrosion resistance. Examples of concrete beams with optimal configurations that were demonstrated in this work showed the potential for significant savings in concrete and reinforcement and the related GWP. In addition, weight was significantly reduced when the textile was used as reinforcement instead of steel. [ABSTRACT FROM AUTHOR]

In this study, a self-compacting high-strength concrete based on ordinary and sulfate-resistant cements was developed for use in textile-reinforced structural elements. The control concrete was made from quartz sand and tap water, and the sea concrete was made from sea water and sea sand for the purpose of applying local building materials to construction sites in the coastal area. The properties of a self-compacting concrete mixture, as well as concrete and textile-reinforced concrete based on it, were determined. It was found that at the age of 28 days, the compressive strength of the sea concrete was 72 MPa, and the flexural strength was 9.2 MPa. The compressive strength of the control concrete was 69.4 MPa at the age of 28 days, and the flexural strength was 11.1 MPa. The drying shrinkage of the sea concrete at 28 days exceeded the drying shrinkage of the control concrete by 18%. The uniaxial tensile test showed the same behavior of the control and marine textile-reinforced concrete; after the formation of five cracks, only the carbon textile reinforcement came into operation. Accordingly, the use of sea water and sea sand in combination with a cement with reduced CO2 emissions and textile reinforcement for load-bearing concrete structures is a promising, sustainable approach. [ABSTRACT FROM AUTHOR]

The growing global energy demand requires solutions that improve energy efficiency in all sectors. The civil construction sector is responsible for a large part of global energy consumption. In this context, phase change materials (PCMs) can be incorporated into construction materials to improve the energy efficiency of buildings. The purpose of this study was to incorporate a PCM to jute fabric, applying it in civil construction as a reinforcement for cement matrices. In order to do that, a method of immersing jute fabric in liquid phase change material, and then coating it with a polymer, was proposed. Treated jute fabric was then used to produce a laminated composite with a cementitious matrix. Morphological, mechanical and chemical characterization of jute textiles was performed, as well as an analysis of the composites’ mechanical and thermal behavior. The results verified that jute textiles absorbed 102% PCM in weight, which was successfully contained in the capillary porosity of jute. The PCM was able to delay the composite’s temperature increase by up to 24 °C. It was concluded that this method can be used to incorporate PCM to natural textiles, producing composites with thermal energy storage properties.

Textile-reinforced concrete (TRC) is highly anticipated as an alternative to reinforced concrete due to its ability to enable lightweight design, free formability, and improved ductility. In this study, TRC panel test specimens were fabricated and four-point loading flexural tests were performed to examine the flexural characteristics of TRC panels reinforced with carbon fabric, and to investigate the effect of the fabric reinforcement ratio, anchorage length, and surface treatment of fabric. Furthermore, the flexural behavior of the test specimens was numerically analyzed using the general section analysis concept of reinforced concrete and compared with the experimental results. Due to bond failure between the carbon fabric and the concrete matrix, the TRC panel showed a large decrease in flexural performance in terms of flexural stiffness, flexural strength, cracking behavior, and deflection. This low performance was improved by increasing the fabric reinforcement ratio, anchoring length, and sand–epoxy surface treatment of the anchorage. Comparing the numerical calculation results with the experimental results, the deflection of the experimental results was approximately 50% larger than the numerical calculation results. This is because the perfect bond between the carbon fabric and the concrete matrix failed, and slip occurred. [ABSTRACT FROM AUTHOR]

To examine the flexural toughness characteristics of textile-reinforced lightweight aggregate concrete (TRLC), a four-point bending test was conducted to assess the impact of varying numbers of textile layers and the inclusion of hydroxypropyl methylcellulose on the ultimate load-bearing capacity and deformation capacity of TRLC thin plates. Six groups of specimens were prepared for the experiment, and the bending capacity of the thin plates in each group was evaluated. The flexural toughness index was utilized to quantify the bending performance of TRLC thin plates. The findings revealed that increasing the number of textile layers improved the initial cracking load, initial cracking deflection, ultimate load, ductility, and flexural toughness of the thin plates. For the specimens without HPMC, the initial cracking load was increased by up to 36.1%, the ultimate load by up to 40.9%, and the flexural toughness index by up to 292% as the number of textile layers was increased. For specimens doped with HPMC, the initial cracking load was increased by up to 61.7%, the ultimate load by up to 246.7%, and the flexural toughness index by up to 65%. The TRLC thin plate containing hydroxypropyl methylcellulose exhibited a reduced initial cracking load yet displayed a stronger matrix consistency and good flexural toughness. Moreover, the enhancement in the ultimate load of TRLC thin plates with hydroxypropyl methylcellulose was more pronounced with an increased number of textile layers, resulting in a significantly higher number of cracks compared to TRLC without hydroxypropyl methylcellulose and an 11.40-fold increase in the flexural toughness index.

The potential of textile-reinforced concrete is broad: it can be used in new structures and in the retrofitting of existing structural components. Designing textile-reinforced concrete requires knowledge about the mechanical properties of different textile types. To this, a standardised tensile test for fibre strands was used. The test aims to statistically characterise two material properties needed in design: ultimate tensile strength and the modulus of elasticity. To this, the influence of length and number of fibre strands were evaluated. The results show that the ultimate tensile strength can be statistically modelled by a Gumbel distribution and the modulus of elasticity can be characterised by a Normal distribution. These findings can be used to derive appropriate partial safety factors for the design value of tensile strength using probabilistic methods, or to directly determine the failure probability of textile-reinforced concrete components.

Textile-reinforced concrete is becoming more and more popular. The material enables the realization of very thin structures and shells, often with organic shapes. However, a problem with this reinforcement occurs when the structure is bent (contains a corner), and the flexural stiffness around this bent area is required. This article presents the design, solution, and load-bearing capacity of an L-shaped rigid frame made of textile-reinforced concrete. Basic material parameters of concrete matrix and carbon textile reinforcement were supplemented by a four-point bending test to calibrate fracture energy Gf, critical compressive displacement Wd, solver type, and other parameters of a numerical model created by Atena Engineering in specialized non-linear structural analysis software for reinforced concrete structures. The calibrated numerical model was used to evaluate different variants of carbon textile reinforcement of the L-shaped frame. The carbon textile reinforcement was homogenized using epoxy resin to ensure the interaction of all fibers, and its surface was modified with fine-grained silica sand to increase the cohesion with the concrete matrix. Specimens were produced based on the most effective variant of the L-shaped frame reinforcement to be experimentally tested. Thanks to the original shaping and anchoring of the reinforcement in the corner area, the frame with composite textile reinforcement is rigid and can transmit the bending stresses in both positive and negative directions. The results of the mechanical loading test on small experimental specimens correspond well to the results of numerical modeling using Atena Engineering software. [ABSTRACT FROM AUTHOR]

Tensile load‐bearing behaviour of concrete components with impregnated textile reinforcement made of natural fibres Recently, the use of natural fibres as a reinforcement in composite building materials have witnessed a growing interest amongst researchers due to their ecological, economical and mechanical properties. In civil engineering, however, they have not been considered in extensive investigations or the development of design guidelines for concrete members with textile reinforcement made of synthetic fibres. In this paper, the uniaxial tensile load‐bearing behaviour of concrete members reinforced with flax fibre textiles (impregnated leno fabrics) is investigated. Therefore, test specimens were casted and tested, varying parameters of the textiles, e. g., the spacing of the weft threads. For a reference, both test specimens reinforced with non‐impregnated textiles and without any reinforcement were investigated. The suitability of this type of reinforcement for concrete members under uniaxial tension is shown by an increase in the ultimate load compared to members without or with less reinforcement. The curves of the stress‐strain diagrams can be divided into three stages typical for reinforced tensile test specimens (state I – uncracked, state IIa – process of cracking and state IIb – completed crack pattern). The differentiation of the areas is clearer with an increasing reinforcement cross‐section. Further, a finely distributed crack pattern with uniform crack widths was observed which supports the findings of the diagrams. [ABSTRACT FROM AUTHOR]

This paper discusses the state of the art in research on the use of textile-reinforced concretes in structural maintenance. Textile-reinforced concretes can be used in structural maintenance for various purposes, including the sealing and protection of the existing building structures, as well as for the strengthening of structures. The first-mentioned aspects are explained in this paper on the basis of example applications. A special focus is placed on the maintenance of heritage-protected structures. The development, characterization, and testing of a textile-reinforced concrete system for a heritage-protected structure are presented. Examples of the application of textile-reinforced concrete for strengthening highway pavements and masonry are also given. In particular, the possibility of adapting the textile-reinforced concrete repair material to the needs of the individual building is one advantage of this composite material. [ABSTRACT FROM AUTHOR]

The flexural behavior of corroded reinforced concrete (RC) beams strengthened with textile reinforced concrete (TRC) was analyzed and discussed in this work. Thirteen beams, including one reference beam, three corrosion-only beams, and nine TRC-strengthened corroded beams, were tested under four-point bending. The failure modes, cracks, bearing capacity, load–displacement curves and ductility of the tested beams were analyzed. The results showed that the TRC played a role in increasing the number of cracks and decreasing the width of the cracks in the corroded RC beams. In terms of improving the bearing capacity, TRC can improve the bearing capacity of corroded beams even more than the reference beams, and the strengthening after removing the concrete cover of corroded RC beams is better than direct strengthening. The corroded beams after TRC strengthening exhibited improved ductility. The energy absorption index of the TRC-strengthened corroded RC beams increased with the increase in the number of textile layers.

Of all industrial sectors, the construction industry accounts for about 37% of carbon dioxide (CO2) emissions. This encompasses the complete life cycle of buildings, from the construction phase to service life to component disposal. The main source of emissions of climate-damaging greenhouse gases such as CO2, with a share of 9% of global emissions, is the production of ordinary cement as the main binder of concrete. The use of innovative approaches such as impregnated carbon yarns as non-corrosive reinforcement embedded in concrete has the potential to dramatically reduce the amount of concrete required in construction, since no excessive concrete cover is needed to protect against corrosion, as is the case with steel reinforcement. At the same time, architectural design options are expanded via this approach. This is achieved above all using novel robotic manufacturing technologies to enable no-cut direct fiber placement. This innovative technological approach to fabricating 2D and 3D biologically inspired textiles, including non-metallic structures for textile-reinforced concrete (TRC) components, will promote an automatable construction method that reduces greenhouse gas emissions. Furthermore, the impregnated yarn which is fabricated enables the production of load-adapted and gradual non-metallic reinforcement components. Novel and improved design strategies with innovative reinforcement patterns allow the full mechanical potential of TRC to be realized. The development of a robotic fabrication technology has gone beyond the state of the art to implement spatially branched, biologically inspired 3D non-metallic reinforcement structures. A combined robotic fabrication technology, based on the developed flexible 3D yarn-guiding and impregnation module and a 3D yarn fixation module, is required to implement this sophisticated approach to fabricate freely formed 3D non-metallic reinforcement structures. This paper presents an overview of the development process of the innovative technological concept.

The article describes measurements of strains of concrete, steel and textile reinforcement with distributed fiber optic sensors (DFOS). The technology of distributed strain measurements gains currently increasing attention within the civil engineering field and indeed the DFOS can be applied in various measurement scenarios providing results and insights which were not possible before. Within this article, the fibers and adhesives that are most commonly used are compared and several measurement scenarios and their results are described, including precise strain measurements with high resolution as well as measurements on large‐scale specimens. Concrete strains were measured in a multiaxial compression stress state and also during setting and hardening and in flexural tests. Strains of the steel and textile reinforcement were monitored along the bond zone and also in flexural tests. Finally, cracking patterns were observed and compared with digital image correlation methods. Validated examples of applications of DFOS in laboratory work are described. [ABSTRACT FROM AUTHOR]

Textile-reinforced concrete (TRC) has many advantages, including corrosion resistance, but TRC is a novel composite material and there is limited experimental research on the flexural behavior of TRC members. This paper aims to experimentally evaluate the flexural behavior of TRC slabs reinforced with nine types of grid-type carbon fiber-reinforced plastic (CFRP) (hereafter referred to as carbon grid) with varying cross-sectional areas, spacings, tensile strengths, and elastic moduli of longitudinal strands. The experimental results show that the maximum load tends to be higher in specimens reinforced with carbon grids with small cross-sectional areas and spacings of strands but high tensile strength. Cross-sectional area and spacing were also revealed to influence the crack-formation stage behavior. On the other hand, stiffness decreased to approximately 8% or lower than the initial stiffness, with cracking in all carbon grid-reinforced specimens; post-peak behavior also exhibited dependency on tensile stress acting on the carbon grids under the maximum load, based on 80% of the tensile strength. [ABSTRACT FROM AUTHOR]

The use of non-metallic, textile reinforcement structures in place of steel reinforcement is a key component in making concrete constructions more sustainable and durable than they currently are. The reason for this is the corrosion resistance of textile reinforcements, which makes it possible to reduce the thickness of the concrete cover and at the same time extend the service life of concrete structures. This reduces the amount of cement required and thus also the emission of the greenhouse gas carbon dioxide (CO2). By means of textile manufacturing technologies, customized, load-adapted reinforcement topologies can be adjusted to the requirements of highly stressed and well-designed concrete components. The objective of this paper is to give an overview of recent research literature dedicated to textile reinforcement structures that are already used for concrete applications in the construction industry as well as those currently under development. Therefore, textile reinforcement structures, which are divided into one-, two- and three-dimensional topologies, as well as common materials used for textile-reinforced concrete (TRC) are reviewed. Most research has so far been devoted to two-dimensional textile reinforcement structures. Furthermore, novel approaches to the fabrication of textile reinforcement structures for concrete applications based on robotic yarn deposition technologies are addressed. [ABSTRACT FROM AUTHOR]