Environmentally-friendly monofilament cellulosic fibres have been widely used as alternatives for conventional steel reinforcement within concrete. Recently, the use of cellulosic fibre fabrics and their fabric reinforced polymer composites as reinforcement materials within and/or outside of construction materials (e.g. concrete) has gained popularity due to their inexpensive cost and favourable specific mechanical properties compared with synthetic fibre fabrics (e.g. E-glass). This review presents a summary of recent development on cellulosic fibre Fabric Reinforced Cementitious (FRC) and Fabric Reinforced Geopolymer (FRG) composites, as well as their cellulosic Fabric Reinforced Polymer (FRP) composites as reinforcements of concrete, masonry and timber structures for civil engineering applications. This review covers: (1) properties (i.e. chemical composition, microstructure, mechanical properties and cost) of monofilament cellulosic fibres and their comparison with synthetic fibres, the relationship between fibre chemical composition and fibre mechanical properties, parameters affect fibre properties; (2) properties (e.g. fabrication of monofilament fibres to fabrics and structures) of cellulosic fibre fabrics, properties of polymer matrices, and properties (i.e. flexural, tensile, impact, insulation and fire properties) of cellulosic fabric FRP composites; and (3) properties (compressive, flexural and tensile and impact properties) of cellulosic FRC and FRG composites, and the properties of cellulosic FRP composites reinforced concrete, masonry and timber structures. In addition, the degradation mechanisms of cellulosic FRC and FRP are discussed. Furthermore, the durability of FRC, FRG and FRP composites are reviewed and the methods to improve the durability of FRC, FRG and FRP composites from the aspects of fibre modification and matrix modification are reviewed and summarized.

A review of recent research on the use of cellulosic fibres, their fibre fabric reinforced cementitious, geo-polymer and polymer composites in civil engineering

Use of geopolymer concrete for a cleaner and sustainable environment – A review of mechanical properties and microstructure

The anchorage of fiber-reinforced polymer (FRP) composites when applied to reinforced concrete (RC) structures as externally bonded reinforcement is an effective means to achieve higher levels of fiber utilization prior to premature debonding failure. Commonly documented anchorage methods for FRP-to-concrete applications demonstrating encouraging results include FRP U-jackets, FRP anchors (also known as spike anchors, among other names), patch anchors (utilizing unidirectional and bidirectional fabrics), nailed metal plates (also known as hybrid bonding), near-surface mounted rods, mechanical fastening, concrete embedment, and mechanical substrate strengthening. Anchorages applied to FRP systems have been verified through experimental testing and numerical modeling to increase the ductility, deformability, and strength of the member and also prevent, delay, or shift the critical mode of FRP debonding failure. Although the benefits of anchorage solutions have now been widely acknowledged by researchers, further studies are required in order to establish reliable design formulations to negate the requirement for ongoing laboratory verification by industry. The present paper is a state-of-the-art review of experimental studies conducted in the area of FRP anchorage systems applied to FRP-strengthened RC flexural members. Available experimental data are compiled and catalogued and an anchorage efficiency factor for each anchorage type under investigation is assigned in order to quantify the anchor’s efficiency. Finally, current shortcomings in knowledge are identified, in addition to areas needing further investigation.

Anchorage Devices Used to Improve the Performance of Reinforced Concrete Beams Retrofitted with FRP Composites: State-of-the-Art Review

Demands for reducing energy consumption and environmental impacts are the major driving factors for the development of natural fiber–reinforced composites (NFRCs) in many sectors. Compared with synthesized fiber, natural fiber provides several advantages in terms of biodegradability, light weight, low price, life-cycle superiority, and satisfactory mechanical properties. However, the inherent features of plant-based natural fibers have presented challenges to the development and application of NFRCs, such as variable fiber quality, limited mechanical properties, water absorption, low thermal stability, incompatibility with hydrophobic matrices, and propensity to agglomeration. Substantial research has recently been conducted to address these challenges for improved performance of NFRCs and their applications. This article reviews the recent advancements of plant-based NFRCs, focusing on strategies and breakthroughs in enhancing the NFRCs’ performance, including fiber modification, fiber hybridization, lignocellulosic fillers incorporation, conventional processing techniques, additive manufacturing (3D printing), and new fiber source exploration. The sustainability of plant-based NFRCs using life-cycle assessment and the burgeoning applications of NFRCs with emphasis on the automotive industry are also discussed.

Recent advancements of plant-based natural fiber–reinforced composites and their applications

Textile reinforced mortars (TRM), also known in the international literature as textile reinforced concrete (TRC) or fabric reinforced cementitious matrix (FRCM) materials, have been widel...

https://ascelibrary.org/doi/pdf/10.1061/%28ASCE%29CC.1943-5614.0000882

Strengthening of Concrete Structures with Textile Reinforced Mortars: State-of-the-Art Review

Flexural analysis of reinforced concrete beams strengthened with a cement based high strength composite material

The paper analyzes the structural behavior of concrete beams reinforced with hybrid fiber-reinforced polymer (FRP)-steel reinforcements. The analysis refers to concrete beams reinforced with FRP rebars placed near the outer surface of the tensile zone, with low cover thickness values, and steel rebars placed at the inner level of the tensile zone, with high cover thickness values, able to protect the steel from the corrosion. Such reinforcement allows one to optimize the structural behavior of beams and guarantees a good level of ductility and rigidity. Results of an experimental and theoretical investigation are presented and discussed. Significant features of the structural behavior regarding deflection, curvature, ductility, crack width, and spacing are pointed out. Ultimate and serviceability conditions are examined, highlighting the influence of mechanical and geometrical parameters affecting the behavior of hybrid reinforced-concrete beams.

Structural Performances of Concrete Beams with Hybrid (Fiber-Reinforced Polymer-Steel) Reinforcements

The paper is devoted to the analysis, both experimental and theoretically, of the bond between a cement based fiber reinforced strengthening material and the concrete substrate. Results of tests on concrete specimens strengthened with the PBO-FRCM system, made by PBO (short of Polypara-phenilene-benzo-bisthiazole) fiber meshes embedded into a cementitious mortar (FRCM, Fabric Reinforced Cementitious Mortar), are presented and discussed. Tests were carried out varying both the bond length, the amount of the strengthening system and the service temperature. Obtained results furnish useful information (i) to determine the loss of bond between the PBO-FRCM system and the concrete, (ii) to define the failure modes and (iii) to evaluate both the influence of environmental conditions (service temperature) and mechanical and geometrical parameters on the loss of bond PBO-FRCM-to-concrete. Test results were, then, utilized to calibrate a local bond-slip relation. A comparison between experimental results and theoretical predictions of the bond-slip law PBO-FRCM-to-concrete is, finally, presented and discussed.

Luciano Ombres

Papers

Flexural analysis of reinforced concrete beams strengthened with a cement based high strength composite material

Structural Performances of Concrete Beams with Hybrid (Fiber-Reinforced Polymer-Steel) Reinforcements

Analysis of the bond between Fabric Reinforced Cementitious Mortar (FRCM) strengthening systems and concrete

Structural performances of reinforced concrete beams strengthened in shear with a cement based fiber composite material

Concrete confinement with a cement based high strength composite material