Despite being strong under compression, concrete is rather weak when subjected to tensile stress. Concrete has been reinforced with a variety of materials over time in order to resist tensile stresses. Among various types of fibers, polypropylene fiber, which is available in a range of sizes, is being used to strengthen concrete. The fiber also increases the concrete’s toughness, durability, and low permeability. Polypropylene fibers may be utilized in place of conventional reinforcement, according to a number of researchers. The aim of this study is to collect information from already carried out research on polypropylene fibers. Important characteristics of concrete, such as workability, compressive, tensile, and flexural strength, are reviewed. The review also explores cracking behavior and failure modes of polypropylene fiber reinforced concrete. Furthermore, durability aspects, such as water absorption, porosity, dry shrinkage, and microstructure study (scan electronic microscopy), were also reviewed. Results indicate that polypropylene fiber improved the mechanical strength and durability of concrete (particularly tensile capacity) but decreased the flowability of concrete. The optimum dose is important, as a higher dose adversely affects strength and durability due to a lack of flowability. Scanning electronic microscopy results indicate that the polypropylene fibers restrict the propagation of cracks, which improves the strength and durability of concrete. The review also indicates that shrinkage cracks are considerably reduced with the addition of polypropylene fibers. Finally, the review also provides future research guidelines for upcoming generations to further improve the performance of polypropylene fibers that reinforce concrete.
The low tensile capacity of concrete often results in brittle failure without any warning. One way to cope with this issue is to add fibers and essentially improve the tensile strength (TS) behavior of concrete and offset its undesirable brittle failure. In recent investigations, basalt fibers (BFs), as compared to a variety of other kinds of fiber, have attracted the attention of researchers. In that respect, BFs exhibit several benefits, such as excellent elastic properties, great strength, high elastic modulus, higher thermal stability, and decent chemical stability. Although many researchers have reported that BFs can be embedded in concrete to improve the tensile capacity, a more profound understanding of its contribution is still needed. However, the information is scattered and it is difficult for the reader to identify the benefits of BFs. Therefore, a detailed assessment is essential to summarize all relevant information and provide an easy path for the reader. This review (part Ⅰ) summarizes all the relevant information, including flow properties, strength properties, and failure modes. Results reveal that BFs can greatly enhance the strength properties and change the brittle nature of concrete to one of ductility. However, it unfavorably impacts the flowability of concrete. Furthermore, the optimal proportion is shown to be important as a higher dose can adversely affect the strength of concrete, due to a deficiency of flowability. The typical range of the ideal incorporation of BFs varies from 0.5 to 1.5%. Finally, the review also indicates the research gap for future research studies that must be cautiously explored before being used in the real world.
The creation of sustainable composites reinforced with natural fibers has recently drawn the interest of both industrial and academics. Basalt fiber (BF) stands out as the most intriguing among the natural fibers that may be utilized as reinforcement due to their characteristics. Numerous academics have conducted many tests on the strength, durability, temperature, and microstructure characteristics of concrete reinforced with BF and have found promising results. However, because the information is dispersed, readers find it problematic to assess the advantages of BF reinforced concrete, which limits its applications. Therefore, a condensed study that provides the reader with an easy route and summarizes all pertinent information is needed. The purpose of this paper (Part II) is to undertake a compressive assessment of basalt fiber reinforced concrete’s durability features. The results show that adding BF significantly increased concrete durability. The review also identifies a research deficiency that must be addressed before BF is used in practice.
The use of glass-fiber-reinforced polymer (GFRP) bars as an alternative to steel bars for reinforcing concrete (RC) structures has gained increasing attention in recent years. GFRP bars offer several advantages over steel bars, such as corrosion resistance, lightweight, high tensile strength, and non-magnetic properties. However, there are also some challenges and uncertainties associated with the behavior and performance of GFRP-reinforced concrete (GFRP-RC) structures, especially under compression and bonding behavior. Therefore, there is a need for comprehensive experimental investigations to validate the effectiveness of GFRP bars in concrete columns. This paper presents a study that aims to address these issues by conducting experimental tests on GFRP-RC columns. The experimental tests examine the mechanical properties of GFRP bars and their bond behavior with concrete, as well as the axial compressive behavior of GFRP-RC columns with different reinforcement configurations, tie spacing, and bar sizes. The findings reveal that GFRP bars demonstrate a comparable, if not superior, compressive capacity to traditional steel bars, significantly contributing to the load-bearing capacity of concrete columns. The study concludes with a set of recommendations for further exploration, underscoring the potential of GFRP bars in revolutionizing the construction industry.
10 January 2023 in Journal of Engineered Fibers and Fabrics
Numerous scientists have studied basalt fiber (BF) reinforced concrete and found encouraging results. However, information is scattered, and compressive assessment is yet necessary to collect the data from prior research on BF, present research advancement, and future research guidelines of BF reinforced concrete. Furthermore, mostly research focus to review on strength and durability aspects of BF reinforced concrete while no researched focus on thermal properties, microstructure analysis and environmental benefits of BF reinforced concrete. Therefore, the primary focuses of this paper are BF treatment, BF reinforced concrete performance at high temperatures, microstructure analysis, environmental advantages, and application in civil engineering. Results show that BF-reinforced concrete performs much better than traditional concrete at high temperatures. Additionally, the use of BF enhanced the heat conductivity of concrete. BF addition to concrete seems to have reduced interfacial transition zone (ITZ) fractures, according to a microstructure study. When opposed to traditional steel fibers, BFs may be thought as reinforcements that are less harmful to the environment. The study also highlights the significance of BFs in the building industry. The assessment also identified research gap research for further studies.