Crimped Steel Fibres Research Articles

Effect of steel fibers on the interfacial shear strength of flyash and GGBS based geopolymer concrete activated with water glass

Concrete, a fundamental construction material, heavily relies on cement, manufacturing process of cement results in significant CO2 emissions, posing environmental concerns. Hence, exploring substitutes for cement becomes imperative to mitigate CO2 emissions. Geopolymer materials emerge as promising alternatives capable of entirely replacing Ordinary Portland Cement (OPC). However, these materials necessitate activators to initiate the polymerization reaction. While Na2SiO3 and NaOH are commonly utilized as activators, their cost-effectiveness is questionable. Moreover, when Ground Granulated Blast Furnace Slag (GGBS) reacts rapidly with these activators. To address these issues and streamline concrete production, “water glass” is employed as an activator, offering a solution to avoid rapid setting and economize the production process. In other hand the production of mass concrete structures, interfaces and joints critical points where cracks may develop. To ensure monolithic behavior, shear ties were advised at the interface in order to establish strong bond strength. However, the efficiency of construction could be decreased by adding more shear ties. The purpose of this study is to evaluate the interfacial shear strength of Geopolymer concrete (GPC), With the addition of different percentages of steel fibers 0.5, 1%,and 1.5%, with shear ties at the interface of push-off specimens. The findings reveal that it is viable to replace two shear ties with one 8 mm-2L shear tie and 1% crimped steel fibers of 30 mm length.

Experimental study on effective utilization of industrial solid wastes in developing Ultra-High Performance Geopolymer Concrete

<p><a><span style="font-size:12.0pt"><span style="line-height:115%"><span style="font-family:"Times New Roman",serif">This experimental study explores the use of Ground Granulated Blast Furnace Slag(GGBS) and dolomite as alkali activated binders and copper slag as aggregate to achieve a cost-effective and sustainable Ultra-High-Performance Geopolymer Concrete(UHPGC). Several concrete compositions utilizing copper slag as a substitute for natural aggregates were formulated. Tests have shown that the inclusion of 100% copper slag fine aggregate leads to significant improvements in the mechanical properties and density of geopolymer concrete. Specifically, the compressive strength increased by 56.8% and the density increased by 17.5%. To understand the influence of dolomite in GGBS binder, several mixes varying dolomite proportion in GGBS were examined. The compressive strength of the 80% GGBS/20% dolomite geopolymer matrix is 32.8% higher compared to the compressive strength of UHPGC with 100% GGBS. The UHPGC mixture containing 1% crimped steel fibers showed the highest compressive strength, measuring 146.6 MPa. The split tensile and flexural strengths of the 20% dolomite matrix show a significant increase of 30.55% and 30.24% respectively compared to the 100% GGBS matrix. The water absorption and porosity of the 100% GGBS specimen were found to be lower compared to the 20% dolomite UHPGC specimen. The microscopic study reveals the positive impact of dolomite and GGBS on enhancing the bonding of the geopolymer matrix along with decreasing permeability. This study highlights the potential of geopolymer technology in producing ultra-high-performance concrete using GGBS, dolomite, and copper slag.</span></span></span></a></p>

Investigation on the flexural behavior of high‐strength fiber‐reinforced concrete

AbstractThe present research investigated the flexural behavior of high‐strength fiber‐reinforced concrete (HSFRC) with six different types of fiber: hooked‐end and crimped steel fibers, chopped and pultruded glass fibers; monofilament and twisted polymeric fibers. An extensive experimental program with 108 specimens for 3‐point bending tests was carried out and the parameters analyzed were the fiber content (0.50%, 0.75% and 1.00% in volume), the fiber type and the compressive strength of the concrete (60 and 90 MPa). Statistical analyses were performed and showed that regardless of the fiber material, increasing the amount of fibers added to concrete increases residual strength and toughness. Limit of proportionality is not affected by the addition of fibers, while postcracking behavior, on the other hand, is controlled by the fibers. Increasing the compressive strength of the concrete matrix affect mainly the limit proportionality of all mixes and the postcracking behavior of the concrete reinforced with hooked‐end steel fibers. The classification of HSFRC and the conditions required for HSFRC for use in structural applications according to the fib Model Code 2010 were also discussed, and it was verified that such conditions are not consistent with the experimental results and should be revised for high‐strength fiber‐reinforced concrete.

Experimental Investigation of the Behavior of SlFCON Column under Eccentric Monotonic Load

Abstract This research delves into the performance of Slurry Infiltrated Fibrous Concrete (SIFCON) columns when subjected to eccentric monotonic loading, through the examination of twenty columns until their point of failure. The research addresses gaps in existing literature by examining the effects of various parameters, including fiber type, volume fraction, and eccentricity ratio, on SIFCON column performance. Results reveal significant correlations between the studied parameters and the structural behavior of SIFCON columns. The investigation shows how the ultimate load affect by the eccentricity ratio, for instance, the hook end steel fiber with a volume fraction of 6%, where the ultimate load decreased by a factor of 0.25 when the eccentricity ratio changed from 0.1 to 0.5. Furthermore, increasing the volume fraction of steel fibers significantly enhances the energy absorption of SIFCON columns. For instance, with the hook-end steel fiber and an eccentricity ratio of 0.3, the energy absorption increased by a factor of 2.76 when the volume fraction of steel fiber changed from 4% to 9%. The type of fibers used plays a pivotal role in the material behavior of SIFCON, with the straight micro fiber exhibiting an ultimate load 2.17 times greater than flat crimped steel fiber types when the volume fraction was 9% and the eccentricity ratio was 0.3. Finally, based on the experimental results, an interaction diagram has been established for three types of SIFCON: straight micro steel fiber with a volume fraction of 12%, hook end steel fiber with volume fractions of 6% and 4%.

Enhancing M30 Grade Concrete: A Comparative Study of Hooked vs. Crimped Steel Fibers in Fly Ash Mixes

The realm of concrete offers vast opportunities for inventive applications, design, and construction methodologies, given its adaptability and cost-effectiveness. Its versatility in meeting diverse requirements has established it as a highly competitive building material. To address escalating structural demands and harsh environmental factors, new cementitious materials and concrete composites are continually being developed, followed by the need for enhanced durability and performance, as well as pressure to utilize industrial waste materials. The research explores the impact of incorporating fly ash and steel fiber into M30-grade concrete, alongside cement, coarse, and fine aggregate, through experimental methods, with the primary aim of determining optimal ingredient proportions for achieving desired strength. The study evaluates compressive strength variations with fly ash ranging from [10%] to [30%] while hooked and crimped steel fibers [ranging from 0% to 1.5%] in concrete, alongside cement, fine and coarse aggregate. Environmental considerations and the imperative to utilize industrial waste have significantly contributed to advancements in concrete technology and sustainability. Through meticulous analysis of results, meaningful inferences are made in relation to the strength attributes of fly ash fiber-reinforced concrete. Two sets of experiments were conducted, one altering fly ash content while maintaining fixed steel fiber content, and the other varying steel fiber content while keeping other parameters constant. The study aims to provide practical insights for engineers seeking cost-effective and sustainable building construction methods, adhering to specified norms (IS Code: 456-2000).

Effect of Elevated Temperature on the Lightweight Aggregate Fibre Reinforced Self-Consolidating Concrete

This study comprehensively investigates fiber-reinforced self-compacting concrete (FRSCC) behavior across multiple grade variations, namely M20, M30, and M40. The study encompasses substituting conventional natural aggregate with sintered fly ash, exploring replacement percentages of 10%, 20%, and 30%. The primary objective of this study is to identify the optimum Strength achieved through a 20% replacement ratio. The assessment of fresh properties of FRSCC was undertaken through rigorous testing protocols involving the L box, J ring, and V funnel tests, following the guidelines stipulated by the European Guidelines for Self-Compacting Concrete (EFNARC). Furthermore, the research extensively analyzed vital mechanical properties, including compressive Strength, split tensile Strength, and flexural Strength. These evaluations provided insights into the influence of sintered fly ash incorporation on the structural performance of FRSCC. The investigation extended to a post-curing temperature study, subjecting the concrete specimens to varying temperatures of 100 °C, 300 °C, 600 °C, and 900 °C, followed by exposure to a 1000 °C heating furnace for 3 hours at each designated temperature. The outcomes of this research yield valuable insights into the potential improvements in the mechanical and thermal properties of FRSCC by integrating sintered fly ash. This study is pertinent for professionals and researchers engaged in optimizing the formulation and utilization of fiber-reinforced self-compacting concrete, with implications for sustainable construction practices and enhanced resilience in diverse thermal conditions. Index Terms: Fibre reinforced lightweight self-compacting concrete, Fly Ash, Sintered fly ash Aggregate, Lightweight Sintered fly ash aggregate concrete, lightweight self-consolidating concrete, Crimped steel fiber.

An Evaluation of Mechanical and Fracture Characteristics of Geopolymer Concrete Incorporating Steel Fibers.

The present research aims to examine the impact of steel fiber inclusion (ranging from 0% - considered as reference, 0.08%, 0.16%, 0.24%, to 0.32%) on the mechanical and fracture characteristics of notched geopolymer concrete unreinforced beams (GCUB). These beams are prepared using fly ash and GGBFS (Ground Granulated Blast Furnace Slag), and the findings are compared with those from plain cement concrete unreinforced beams. The investigation encompasses various parameters including compressive strength, bending strength, split tensile strength, fracture energy (GF), crack mouth opening displacement (CMOD), and stress intensity factor (KIC). The primary focus is to assess how the inclusion of crimped steel fibers influences the ability of geopolymer concrete to arrest cracks. The outcomes obtained from the study underscore the effectiveness of crimped steel fibers in mitigating crack propagation and averting brittle fractures within notched geopolymer concrete unreinforced beams. The results indicate notable enhancements across all fracture and mechanical parameters upon the introduction of steel fibers. This points towards the positive impact and efficiency of steel fibers in augmenting the behavior of geopolymer concrete, making it more resistant to crack propagation and brittle failure.

Investigation on residual bond strength and microstructure characteristics of fiber-reinforced geopolymer concrete at elevated temperature

Fiber-reinforced geopolymer concrete has been attracting attention and interest worldwide due to its sustainable properties. However, few studies have reported the pull-out behaviour of fiber-reinforced geopolymer concrete (GPC) at elevated temperatures. In order to bridge this knowledge gap, a series of detailed investigations aimed to investigate the effect of elevated temperatures on the mechanical and microstructure properties of fiber-reinforced geopolymer concrete. In the present investigation, crimped steel fibers (SF), polypropylene fibers (PF), basalt (BF), and hybrid fibers such as SF:PF and PF:BF is employed to develop the GPC. Alkaline activators such as sodium hydroxide (NaOH) of 8 M and 10 M and Na2SiO3/NaOH ratios of 2.5 are used in the production of M35 and M40 grade GPC. Compressive strength, weight loss, crack pattern, bond strength, and microstructure of fiber-reinforced GPC specimens have been evaluated, after exposing to higher temperature following ISO 834 standard fire curve. Results from the conducted tests show that adding various types of fibers improves the compressive strength and bond strength of the GPC specimens. More specifically, amongst all tested specimens, the exposed GPC-BF shows lesser weight loss and higher residual compressive strength with fewer cracks on the surface of the specimens. on the other hand, GPC with SF shows higher residual bond strength than other fiber-reinforced GPC specimens. Microstructure analysis (SEM/EDAX) confirms the extent of damage and contribution of fiber in the temperature-exposed GPC. A statistical relationship and correlation has been obtained between compressive and bond strength.

Strengthening Stainless Steel Tubular Beams using Fibre-reinforced Concrete incorporating Sugarcane Bagasse Ash

Stainless steel tubular beam sections have been increasingly utilised for structural applications due to the enhanced properties of stainless steel over conventional mild steel. However, thin-walled stainless steel sections are not effectively used for several practical applications due to the higher costs and its response to easily undergo local buckling under flexural loading. Consequently, to overcome these effects, concrete infilling is a generally preferred strengthening mechanism that enhances the overall capacity and makes the sections economic. Earlier research studies on the flexural behaviour of various concrete-infilled stainless steel composite beam specimens are highly limited. Therefore, this study mainly focuses on the flexural behaviour of bare stainless steel tubular beams, sugarcane bagasse ash blended concrete-infilled stainless steel composite beam, and fibre-reinforced sugarcane bagasse ash blended concrete-infilled stainless steel composite beam. The study uses sugarcane bagasse ash as a pozzolan in the infill concrete to produce durable and sustainable concrete. In the same manner, crimped steel fibres are incorporated to enhance the ductility of the beam specimen. The parameters such as ultimate strength, maximum flexural deformation, initial stiffness, failure modes, ductility, and moment-rotation profiles were comprehensively investigated for all the beam specimens. Furthermore, numerical modelling was performed for the fibre-reinforced sugarcane bagasse ash blended concrete-infilled stainless steel composite beam specimen and was validated with the experimental results. It was witnessed that adding infill concrete to the stainless steel tube enhanced the beam specimens' load-carrying capacity, stiffness and ductility.

Impact resistance of micro and macro crimped steel fibre reinforced self-compacting concrete with SCM

This paper aims to investigate the impact resistance of micro and macro crimped steel fibre-reinforced self-compacting concrete (SFRSCC) with the volume fractions of 0.25%, 0.50%, and 0.75%. A total of seven mixtures were investigated with different volume fractions of steel fibres considering in terms of fresh, mechanical properties and impact resistance. The total binder contains 60% cement and 40% supplementary cementitious materials (SCM) with a combination of 30% fly ash and 10% silica fume. The addition of steel fibre decreases the workability of SCC. However, the inclusion of SCM compensates and increases its workability. Mechanical behaviour of micro and macro steel fibre reinforced SCC outperforms the conventional SCC in terms of compressive strength, split tensile strength and flexural strength. The impact resistance of SFRSCC is determined through a modified testing procedure derived from the guidelines provided by ACI 544.2 R. It is observed that the volume fraction of both 0.75% micro and macro steel fibre has improved impact resistance with increase percentage of energy absorption of 180% and 240%. The relationship between UPV and impact test results found that the number of blows can be predicted using the UPV values from the regression equations. The results of the Weibull distribution (WD) and reliability analysis indicate that 80% (τ = 0.8) of the SFRSCC samples are reliable enough to survive 14 blows at first crack and 20 blows at failure crack. The incorporation of crimped steel fibres into the concrete matrix led to the even distribution of impact loading throughout the concrete specimen with the help of steel fibres, thereby improving the impact resistance of SCC.

Computational Fracture Evolution Analysis of Steel-Fiber-Reinforced Concrete Using Concrete Continuous Damage and Fiber Progressive Models.

The process of concrete cracking is a common problem because the first micro-cracks due to the loss of moisture may appear even before the concrete is loaded. The application of fracture mechanics allows for a better understanding of this problem. Steel-fiber-reinforced concrete (SFRC) samples with a notch were subjected to a three-point bending test, and the results for crack energy were used to analyze the concrete's material properties. In this paper, an experimental and numerical analysis of SFRC with rapid changes in the force (F) crack mouth opening displacement (CMOD) curve (F-CMOD) is presented. In order to obtain the relevant F-CMOD diagrams, three-point bending tests were carried out with non-standard samples with a thickness equal to one-third of the width of standard samples. For analysis purposes, crimped steel fibers were adopted. A probabilistic analysis of the most important parameters describing the material in question, such as peak strength, post-cracking strength, crack mouth opening displacement (CMOD), fracture energy, and the post-cracking deformation modulus, was conducted. The tests and the analysis of their results show that the quasi-static numerical method can be applied to obtain suitable results. However, significant dynamic effects during experiments that influence the F-CMOD curves are hard to reflect well in numerical calculations.

Effect of Steel Fibers on the Properties of Refractory Free Cement Concrete

Free cement refractory concrete is a type of refractory concrete with replacing alumina cement by bonding materials such as white kaolin, red kaolin and fumed silica. The free cement refractory concrete used in many applications like Petrochemicals, iron furnaces and cement production industries. The research clarifies the effect of steel fibers with two types crimped steel fibers and hooked steel fibers with percentages 0.5%, 1% and 1.5% by volume from weight of bauxite aggregates. The additions of steel fibers with two types gave good properties in high temperatures where the specimens keep the dimension without failure and the properties made the best. the percentage of increasing for thermal conductivity was 44% for 1.5% crimped fibers and 42.8% for 1.5% hooked end fibers and the percentage increasing in bulk density of free cement refractory concrete was 30% for 1.5% crimped fibers and 27% for 15% hooked end fibers . From this study can be concluded that the best types of steel fibers which used in free cement refractory concrete is the crimped type with percentage 1.5%.

Post-fire investigation on the mechanical properties and physical characteristics of fibre-reinforced geopolymer concrete

PurposeThe construction industries at present are focusing on designing sustainable concrete with less carbon footprint. Considering this aspect, a Fibre-Reinforced Geopolymer Concrete (FGC) was developed with 8 and 10 molarities (M). At elevated temperatures, concrete experiences deterioration of its mechanical properties which is in some cases associated with spalling, leading to the building collapse.Design/methodology/approachIn this study, six geopolymer-based mix proportions are prepared with crimped steel fibre (SF), polypropylene fibre (PF), basalt fibre (BF), a hybrid mixture consisting of (SF + PF), a hybrid mixture with (SF + BF), and a reference specimen (without fibres). After temperature exposure, ultrasonic pulse velocity, physical characteristics of damaged concrete, loss of compressive strength (CS), split tensile strength (TS), and flexural strength (FS) of concrete are assessed. A polynomial relationship is developed between residual strength properties of concrete, and it showed a good agreement.FindingsThe test results concluded that concrete with BF showed a lower loss in CS after 925 °C (i.e. 60 min of heating) temperature exposure. In the case of TS, and FS, the concrete with SF had lesser loss in strength. After 986 °C and 1029 °C exposure, concrete with the hybrid combination (SF + BF) showed lower strength deterioration in CS, TS, and FS as compared to concrete with PF and SF + PF. The rate of reduction in strength is similar to that of GC-BF in CS, GC-SF in TS and FS.Originality/valuePerformance evaluation under fire exposure is necessary for FGC. In this study, we provided the mechanical behaviour and physical properties of SF, PF, and BF-based geopolymer concrete exposed to high temperatures, which were evaluated according to ISO standards. In addition, micro-structural behaviour and linear polynomials are observed.

Influence of engineering fibers on fresh and mechanical properties of geopolymer concrete

Geopolymer concrete (GPC) is gaining popularity due to its sustainable nature, and therefore it is called as “green” concrete, but it is more brittle than conventional concrete. To reduce the brittleness in GPC, the fibers must be added. Fiber-reinforced concrete (FRC) is gaining popularity for practical engineering applications due to its excellent tensile strength, flexural strength, durability, and fracture properties. However, applying FRC to infrastructure projects and construction requires a thorough understanding of FRC's workability and mechanical properties. In the current study, the primary objective is to determine the optimum amount of fiber such as basalt fiber (BF), crimped steel fiber (SF), and polypropylene fiber (PF) required for the development of GPC (M35 and M40 grade GPC). The present work is divided into two stages. The slump test, tensile strength test (TS), and flexural strength test (FS) are used in the first stage to obtain optimized fiber dosage after 7 and 28 days of ambient curing. In the second stage, the optimized fibers are used to evaluate the compressive strength (CS) of GPC. The alkaline binder includes FA and GGBS, and the concentration of NaOH is 8 M and 10 M, respectively. The test results demonstrate that as the volume of fiber content increases, each fiber's workability decreases gradually. In the case of 8 M and 10 M of NaOH, as compared to GPC-BF and GPC-PF, the TS and FS of GPC-SF showed maximum strength, ranging between 120.71% and 109.77%. In the case of CS, the BF-based GPC exhibited the highest strength in 8 M and 10 M, with a range of 16%.

Impact Resistance of Micro and Macro Crimped Steel Fibre Reinforced Self-Compacting Concrete with Scm

Impact Resistance of Micro and Macro Crimped Steel Fibre Reinforced Self-Compacting Concrete with Scm

Investigation of Impact Resistance of High-Strength Portland Cement Concrete Containing Steel Fibers.

Impact resistance of Portland cement concrete (PCC) is an essential property in various applications of PCC, such as industrial floors, hydraulic structures, and explosion-proof structures. Steel-fiber-fortified high-strength concrete testing was completed using a drop-weight impact assessment for impact strength. One mix was used to manufacture 320 concrete disc specimens cured in both humid and dry conditions. In addition, 30 cubic and 30 cylindrical specimens were used to evaluate the compressive and indirect tensile strengths. Steel fibers with hooked ends of lengths of 20, 30, and 50 mm were used in the concrete mixtures. Data on material strength were collected from impact testing, including the number of post-first-crack blows (INPBs), first-crack strength, and failure strength. Findings from the results concluded that all the steel fibers improved the mechanical properties of concrete. However, hooked steel fibers were more effective than crimped steel fibers in increasing impact strength, even with a smaller length-to-diameter ratio. Concrete samples containing hybrid fibers (hooked + crimped) also had lower compressive strength than the other fibers. Comparisons and analogies drawn between the test results and the static analyses (Kolmogorov–Smirnov and Kruskal–Wallis) show that the p-value of the analyses indicates a more normal distribution for curing in a humid environment. A significant difference was also observed between the energy absorptions of the reinforced mixtures into steel fibers.

The Impact Resistance and Mechanical Properties of Recycled Aggregate Concrete with Hooked-End and Crimped Steel Fiber.

The utilization of recycled coarse aggregate (RCA) from construction and demolition waste (CDW) is a sustainable solution to protect the fragile natural environment and save the diminishing natural resources. The current study was aimed at exploring the impact resistance and mechanical properties of recycled aggregate concrete (RAC) affected by hooked-end steel fiber (HF) and crimped steel fiber (CF). Fifteen concrete mixtures considering different RCA substitution ratio, steel fiber dosage, and steel fiber shapes were designed. Meanwhile, a statistical analysis method-based Weibull distribution was introduced to evaluate the variations of impact test results, presented using a reliability function. Lastly, the microstructural morphologies of interfacial transition zones at the cement paste/aggregate and cement paste/fiber interfaces were observed using a scanning electron microscope (SEM). The experimental results showed that the impact resistance and mechanical properties mildly decreased with the increase in substitution ratio of RCA, whereas they conclusively increased with the increase in steel fiber content. Steel fiber recycled aggregate concrete (SFRAC) with 1.5% steel fiber content had the best impact resistance, and its initial cracking times and final failure times were 3.25–4.75 and 8.78–29.08 times those of plain RAC, respectively. HF has better impact resistance than CF. The SEM observations of microstructures indicated that the hardened cement paste of natural aggregate concrete (NAC) was more compact than that of RAC. Steel fiber had a better connection with the cement paste interface than that of aggregate and cement paste owing to better thermal conductivity. This research could be a guide for SFRAC as a structural material in practical engineering, steering the construction industry toward the circular economy.

Investigation of mechanical and durability properties of brick powder-added White Cement composites with three different fibers

• 5% brick powder increased the strength results of White Cement composite production. • The highest results were obtained with the crimped steel fiber for fiber-reinforced mortar. • The lowest results were obtained with the copper-coated steel fiber for fiber-reinforced mortar. • The brick powder and fiber added composites resisted the durability tests. Traditional Portland Cement is used extensively in the construction industry today. Portland Cement has a gray color and has been explored with numerous substitutes. With the increasing interest in concrete technology, the interest in composite materials with higher performance and strength has gained more importance. White Cement (WC) is an important cement type in this field. However, studies of substitute materials for White Cement are limited and more research is needed. In this study, while White Cement and clay brick powder (CBP) were substituted at three different rates (5%, 10%, and 15%), three different fibers (copper-coated (CC) steel fiber, crimped (C) steel fiber, and basalt (B) fiber) were used at the ratio of 0.4% to examine the effect of fibers at the same time. The compressive and flexural strengths of the prepared series were investigated for 28 and 90 days. Three different durability tests were applied after 90 days: elevated-temperature test (250, 500, and 750 °C), freezing-thawing test (90 cycles), and sulfate effect (90 days). Following the durability tests, weight and strength values were compared. In addition, SEM and XRD analyzes were made while making comparisons before and after the durability test of the samples and a visual examination was made in the durability conditions. The use of 5% brick powder increased the strength values due to the formation of C-A-S-H and C-S-H gels due to its higher Al 2 O 3 and SiO 2 content, while the use of higher brick powder caused a decrease in strength. While the fibers contributed positively to the strength values, the highest increase was in the longer crimped steel fiber added sample and the lowest increase was in the shorter copper-coated steel fiber added sample. While there was a 13% increase in compressive strength in the crimped steel fiber and 5% brick dust added sample compared to the control sample, there was a 21% increase in flexural strength. As a result of the durability tests, the samples behaved in similar order and maintained their stability despite significant losses.

Mechanical and Microstructural Analysis of Waste Ceramic Optimal Concrete Reinforced by Hybrid Fibers Materials: A Comprehensive Study

Combining different types of fibers inside a concrete mixture was revealed to improve the strength properties of cementitious matrices by monitoring crack initiation and propagation. The contribution of hybrid fibers needs to be thoroughly investigated, considering various parameters such as fibers type and content. The present study aims to carry out some mechanical and microstructural characteristics of Waste Ceramic Optimal Concrete (WOC) reinforced by hybrid fibers. Reinforcement materials consist of three different fiber types: hook-ended steel fiber (HK), crimped steel fiber (CR) and polyvinyl alcohol (PVA) fibers and the effect of their addition on the waste ceramic composites’ mechanical behaviour. Furthermore, a microstructural analysis was carried out to understand the waste ceramic matrix composition and its bonding to hybrid fibers. Results showed that the addition of hybrid fibers improved the strength characteristics of the ceramic waste composites. For instance, the existence of PVA-CR increased the tensile and flexural strength of the waste ceramic composite by 85.44% and 70.37%, respectively, with respect to the control sample (WOC). As well as hybrid fiber exhibits improved morphological properties as a result of increased pore filling with dense and compact structure, as well as increased C–H crystals and denser structure in pastes as a result of the incorporation of hybrid fibers into the concrete mix. The present experimental research shows the choice of using steel fiber with PVA as a reinforcement material. The idea of adding hybrid fiber is to prepare the economic, environmental, and technological concrete. Moreover, it offers a possibility for improving concrete’s durability, which is vital. Finally, it was concluded that steel fiber is more durable, and stiffer and provides adequate first crack strength and ultimate strength. In contrast, the PVA fiber is relatively flexible and improves the post-crack zone’s toughness and strain capacity.

A Review: “Experimental Study on Steel Fiber Reinforced Concrete Using flat Crimped & Round Crimped Type Steel Fiber.”

Abstract: Steel Fibre Reinforced Concretes are characterized by high tensile and flexural strengths and high ductility, as well as by a high compressive strength and a very good workability. Ductility and strength of concrete can be improved at lower fiber contents, where fibers are used in combination rather than reinforcement with a single type of fiber. Durability problems concerning one type of fiber may be offset with the presence of a second type of fiber. Steel Fiber is added by 1% volume of concrete. The different concrete mixesalong with control mix proportions as 100% round crimped type fiber, 50% round crimped type fiber -50% flat crimped type fiber and 100% flat crimped type fiber. Two types of crimped steel fiber i.e. round crimped type steel fiber and flat crimped steel fiber are used of length having 50mm. An extensive experimental investigation consisting of 12 specimen of size 50 x 10 x 10cm for determining flexural strength, 12 specimen for compressive strength and 12 specimen for split end test are used.In the experiment, an combination of steel fibre with concrete is used, which improved various mechanical properties and the strength. This review study is a trial of givingsome highlights for inclusion of steel fibers especially in terms of using them with new mix ratio combinations with concrete.