Fiber-reinforced Concrete Research Articles

Experimental investigation on the mechanical characteristics of ultra-high-molecular-weight polyethylene (UHMWPE) based fiber-reinforced concrete

This study investigates the static and dynamic mechanical properties of ultra-high-molecular-weight polyethylene (UHMWPE) fiber-reinforced concrete (FRC). The properties were assessed by conducting compressive strength, flexural strength, split tensile strength, and impact resistance. The pneumatic dispersion method was used for the UHMWPE fiber pretreatment. The concrete mix was prepared with a water-to-cement ratio of 0.6 and an aggregate fineness modulus of 5.39. UHMWPE fibers, measuring 6 mm and 12 mm in length and incorporated at addition rates of 5 wt‰, 10 wt‰, 15 wt‰, and 20 wt‰ of the fiber-to-cement weight ratio, were added to the concrete specimens for testing. The results showed that the FRC with 12 mm UHMWPE fiber and 15 wt‰ fiber-to-cement weight ratio achieved the best performance in the compressive strength test, and it increase 51.92 % compared with benchmark specimen. For the flexural test results, the 6 mm UHMWPR fiber performed best at a 15 wt‰ addition ratio, and it increase 18.77 % compared with benchmark specimen. Moreover, the FRC with 12 mm UHMWPR fiber excelled at a 20 wt‰ addition ratio in split tensile strength test, and it increase 92.14 % compared with benchmark specimen. The drop weight test indicated that a 15 wt‰ addition ratio with 12 mm UHMWPE fiber significantly enhanced performance, with an average impact number improvement of 5527 % under a 50 Joule impact energy, compared to the benchmark specimens. The study concludes that incorporating UHMWPE fiber into concrete significantly boosts its static and dynamic performance.

Effectiveness evaluation of different steel fibers on the shear strength of reinforced SFRC slender beams without web rebars

Current studies have mainly focused on the effect of specific steel fibers on the shear performance of steel fiber-reinforced concrete (SFRC) slender beams. However, there has been a lack of in-depth research evaluating the effectiveness of different steel fibers through a statistically comparative analysis of experimental data from various researchers. Existing design methods do not fully account for the impact of all types of steel fibers on the shear capacity of SFRC slender beams, providing very limited guidance on selecting appropriate steel fibers. This highlights the need for research to verify the strengthening effectiveness of different steel fibers. This paper establishes databases comprising 232 shear-failed reinforced SFRC beams with four other types of steel fibers straight wire, deformed wire, deformed cut-sheet and ingot mill, based on a comprehensive review of published literature. These databases complement an existing database of 280 reinforced SFRC beams using hook-end wire steel fibers as shear reinforcement. The databases are used to evaluate the validity of several well-known existing formulas for predicting the shear capacity of beams and to determine the fiber bond factor values that reflect the diverse strengthening effects of different steel fibers. Utilizing a simi-empirical synergetic prediction model for the shear strength of reinforced SFRC slender beams with hook-end wire steel fibers, the shear resistances of test beams in databases with the other four types of steel fiber are analyzed. The primary contributors to shear capacity are identified as the uncracked shear-compression SFRC and the dowel action of longitudinal tensile steel bars. The contribution of steel fibers is linked to the shear resistance of uncracked shear-compression SFRC. From a practical design perspective, a conservative prediction formula is verified, aligning with the lower boundary of the tested shear strength obtained from the database of beams. Finally, suitable steel fibers for s enhancing the shear strength of reinforced SFRC beams without web rebars are suggested based on their effectiveness.

Advancements in light-gauge steel rectangular CFST columns: A comprehensive experimental study

This research examines the structural performance of rectangular Concrete-Filled Steel Tube (CFST) columns produced from light-gauge steel tubes. The study aimed at improving their strength, stiffness, and ductility via a combination of external confinement, internal stiffeners, and hybrid fiber-reinforced concrete (HFRC) infill. An axial compression test was carried out on a total of 18 samples, comprising of unconfined hollow steel tubes, bracing-confined tubes, ring-confined tubes, unconfined CFST, bracing-confined CFST, and ring-confined CFST columns. To restrict lateral expansion, external restraints including bracing and ring-type steel rods, were spot-welded to the outer steel tube. To optimize the column’s load carrying capacity and mitigate buckling effects, the spacing of the confinements were systematically designed. HFRC infill and alterations in the inner profile with and without vertical strips and studs, were also taken into consideration. The experimental results plus the failu re modes, axial load-deflections and load-deflection curves were analyzed to understand the behavior of the CFST columns. Performance indicators such as strength and stiffness ratios, and confinement effect ratio, were assessed for the various sample types. This research accentuates the efficiency of external confinement techniques in improving strength and ductility. Existing design codes were adopted for the theoretical estimations of the axial compression capacity, highlighting variations in predictions. This study significantly contributed beneficial understandings of the structural performance of rectangular CFST columns, stressing the importance of both internal and external confinements and HFRC infill.

Study on impact resistance performance of MSWIFA-based low-carbon fiber-reinforced concrete

The accumulation of carbide slag (CS), red mud (RM), and municipal solid waste incineration fly ash (MSWIFA) has led to significant environmental pollution issues, necessitating urgent resource utilization. Building upon the previously developed CS-MSWIFA synergistic activation RM-slag cementitious system, this study aims to further incorporate iron tailings sand and polypropylene fibers to prepare fiber-reinforced concrete. The systematic investigation focuses on the influence of cementitious material types, aggregate types, fiber shapes, lengths, and dosages on the impact resistance of concrete. Furthermore, an impact damage evolution equation and life prediction model were developed based on the two-parameter Weibull distribution. Results indicate that the type of cementitious material and aggregate has minimal influence on the impact resistance of concrete, while the addition of fibers significantly enhances its impact resistance, shifting the failure mode from brittle to ductile. Mesh polypropylene fibers with a length of 12 mm and a volume dosage of 1.0 % demonstrate excellent impact resistance, with initial and final crack numbers reaching 78 and 105, respectively. This represents an increase of 136.4 % and 200.0 % compared to the control concrete without fibers. The findings of this study offer new avenues for the resource utilization of solid waste and provide theoretical foundations and technical support for the potential application of solid waste based fiber-reinforced concrete in structural engineering.

A finite element analysis method for random fiber-aggregate 3D mesoscale concrete based on the crack bridging law

Mesoscale modeling is an emerging analytical method that can be used to study fiber-reinforced concrete. However, fine fibers with micrometer diameters are distributed in millions in a standard specimen, so it is impossible to establish a mesoscale model and further analyze it, which severely limits the investigation of the reinforcement mechanism of fine fibers on concrete. This paper efficiently established a highly applicable mesoscale analytical model for random fiber-polyhedral aggregate concrete in Abaqus software based on a comprehensive examination of the crack bridging law and the supplementation of the fiber spacing theory, combined with the improvement of the algorithms of aggregate generation, fiber arrangement, and the judgment of the fiber-aggregate contact by the secondary development method of Python, as well as the matrix-dual arrangement method. Additionally, basalt fiber concrete and mortar specimens were prepared and tested, and the parameters of the model were calibrated to verify the model's authenticity. The result shows that the method proposed in this paper can accurately and efficiently perform mesoscale concrete analysis with fine fibers. In the peak load stage, the fiber has the strongest alleviation effect (Δ = 0.033) on the matrix damage, 10 times that of the crack initiation stage (Δ = 0.003). With the development of damage, fiber stress increases gradually from the crack initiation stage (0.68 σfu), and the growth rate (41.53 %) is the largest at the peak load stage (σfu), which reveals the complex dynamic bridging effect of fiber on the matrix. This investigation proposes a novel and broad applicability methodology for the finite element analysis of fiber-reinforced aggregate mesoscale concrete.

Flexural behaviour of bamboo concrete beams

Bamboo plants can be found in both tropical and non-tropical locations of the world, it is thought of as a naturally occurring, quick-growing, and renewable resource. Bamboo is seen as a good alternative for construction due to the high energy requirements of current building materials and the limited availability of other naturally occurring materials like wood., bamboo is considered a good alternative for construction. To minimize carbon footprints in the environment, the research illustrates the flexural properties of Bamboo reinforced concrete to be able to use it as a successful replacement for steel bars. To study the flexural behavior, the total reinforcement constant and partially replaced steel with bamboo at 0%, 25%, 50%, 60%, 75% & 100%. Bamboo is a versatile material that can be used in a variety of construction applications, and it can also be employed in a variety of housing applications, notably roofing, and flooring. Moreover, bamboo culms are often used directly as structural members such as beams, slabs, and columns without any alteration. Bamboo can also be used as reinforcement in concrete as a replacement for steel. The shear and flexural behavior of bamboo-reinforced concrete beams is significantly better than that of plain concrete beams. Furthermore, bamboo fiber-reinforced concrete is a good alternative to existing fiber-reinforced concrete, such as glass and steel fibers.

Rubber concrete reinforced with macro fibers recycled from waste GFRP composites: Mechanical properties and environmental impact analysis

With the rapid growth of the automotive industry, a huge amount of tires have been produced, which inevitably led to the accumulation of scrap tires. A typical disposal routine is using scrap tires as a partial substitute for fine aggregate in concrete, producing so-called rubber concrete. However, the detrimental effects of rubber particles on concrete properties have been identified, which, to some content, hinders their broader application. The discrete fiber addition is shown to be effective in minimizing this detrimental effect, and this paper has therefore attempted to introduce macro fiber produced from waste glass fiber reinforced polymer (GFRP) into the rubber concrete system. Three series of specimens for compression, splitting, and flexural testing were tested. The test variables include concrete type (i.e., normal concrete, rubber concrete, and modified rubber concrete); and macro fiber content (i.e., 0–2 %). In addition, the inverse analysis is performed to transform the flexural test response into the tensile constitutive law of the fiber-reinforced concrete (FRC). The test results revealed macro fibers have little effect on the compressive strength of normal concrete and rubber concrete and a detrimental effect on that of modified rubber concrete. Incorporated fibers notably improve the splitting and flexural performance of normal concrete and rubber concrete. In addition, the cost and environmental impact analysis revealed that the addition of recycling products increases the concrete cost and results in a maximum reduction of carbon emissions by 17.3 % and embodied energy emissions by 80 %.

Analysis of synergistic effect of bending energy absorption capacity of fiber reinforced concrete based on fiber distribution characteristic

Macro fibers could contribute to absorb energy through fiber sliding, which significantly enhance the energy absorption capacity of concrete beams. In this research, the synergistic effect of macro steel fibers and polypropylene (PP) fibers on the energy absorption capacity of concrete under bending is under investigated. The three-point bending test is adopted to compared the residual flexural strength and energy absorption capacity of fiber reinforced concrete (FRC) beams. Besides traditional Load-deflection curves, the energy absorption-crack mouth opening displacement (CMOD) curves are adopted to reflect the toughness of FRC beams. The synergistic effect of steel fibers and PP fibers on the residual flexural strength and energy absorption capacity is evaluated. A linear function is proposed to describe the relationship between energy absorption and CMOD for FRC beams. In addition, fiber distribution on cracking surface of FRC beams is analyzed through fiber distribution density and fiber spacing to explain the synergistic effect. Experimental results indicate that the behaviors of FRC beams, that is, residual flexural strength and energy absorption, are improved by adding macro fibers, in particular macro steel fibers. Besides, the relationship between energy absorption and CMOD of FRC beams can be fitted very well by the linear function. The slope of the energy absorption and CMOD relationship is adopted to analyze the contribution of macro fibers to energy absorption. The uniformity of fiber distribution is improved by increasing of fiber dosage for SFRC and PFRC beams. The hybrid use of macro steel fibers and PP fibers demonstrates a positive synergistic effect on the energy absorption capacity and flexural strength of concrete. The improved fiber spacing and fiber distribution density of hybrid fiber on cracking surface contribute to the positive synergistic effect observed in hybrid fiber reinforced concrete (HyFRC) beams.

Predicting shear strength of fiber-reinforced concrete beams reinforced with longitudinal FRP bars with machine learning techniques

ABSTRACT This study investigates the shear strength prediction of Fibre-Reinforced Concrete (FRC) beams reinforced with Fibre-Reinforced Polymer (FRP) bars and without stirrups through the application of Machine Learning (ML) techniques. The utilisation of FRP bars, particularly Glass Fibre-Reinforced Polymer (GFRP) and Basalt Fibre-Reinforced Polymer (BFRP) bars, has emerged as a promising alternative to traditional steel reinforcement due to their superior mechanical properties and corrosion resistance. Moreover, the incorporation of macro- and micro-discrete fibres into concrete compositions enhances both shear and flexural behaviour while reducing crack propagation induced by tensile stresses. The primary objective of this research is to develop accurate predictive models for the shear capacity of FRP-reinforced concrete beams, considering various influential parameters. Six different ML techniques, namely Multiple Linear Regression (MLR), Gaussian Process Regression (GPR), k-Nearest Neighbors (KNN), Support Vector Machines (SVMs), Artificial Neural Networks (ANNs) and Random Forest Regression (RFR), are employed to analyse the complex interactions between input variables, such as fibre type, bar diameter, concrete compressive strength, beam dimensions and the resulting shear strength. By leveraging these computational approaches, we aim to overcome the limitations of conventional analytical methods and provide robust predictions for structural design and optimisation.

Three dimensional simulations of FRC beams and panels with explicit definition of fibres-concrete interaction

High performance concrete (HPC) is a quite novel material which has been rapidly developed in the last few decades. It exhibits superior mechanical properties and durability comparing to normal concrete. HPC can achieve also superior tensile performance if strong fibres (steel or carbon) are implemented in the matrix. Thus, there exist the unabated interest in studying how the addition of different types of fibres modifies the behaviour of HPC. Nowadays, a standard numerical approaches to model the behaviour of fibre reinforced concrete (FRC) are carried out by means of the smeared or discrete crack modelling of homogenous media with appropriately changed stress-strain relationships. The objective of this paper is to develop a new and efficient mesoscale modelling approach for steel fibre reinforced high-performance concrete. The main idea of presented approach is to assume the fully 3D modelling with taking into account explicitly the distribution and orientation of the steel fibres. As a benchmark, results obtained from experimental campaign on beams and panels made from high-performance concrete with steel fibres of different sizes and dosages were taken. Results of numerical simulations were directly compared with experimental outcomes in order to validate and calibrate FE-model and to introduce the efficient numerical modelling tool.

Improvements in the Characteristics of Plant Fiber Reinforced Concrete

Plant Fiber is lightweight, has a high specific strength, and the ultimate elongation is high and can improve the shortcoming of concrete. Concrete is easy to crack and break, and its tensile strength and other mechanical properties are not high. The chemical composition and mechanical properties of some plant Fibers that are often used are analyzed first. The modification of plant Fiber will also be discussed. Firstly, the chemical composition and mechanical properties of some plant Fibers are analyzed, and the modification methods of plant Fibers are also discussed; then, the mechanical properties of plant Fiber-reinforced concrete, hydration properties, heat preservation properties, durability, and other properties of plant Fiber-reinforced concrete are analyzed and summarized in detail. The conclusions are as follows. When the strength of concrete is increased by plant Fiber, the long Fiber is the best tensile strength method, the short Fiber is the most practical, and the length and content of the Fiber. The influence of factors such as water-cement ratio; plant Fiber can delay the release of the heat of hydration of cement by changing the hydration characteristics of cement, thereby improving the anti-cracking ability of mass concrete; concrete plant Fiber can improve the thermal stability and durability, and the lyotropic effect of plant Fiber on concrete Affect the flowability of paste. Plant Fibers can improve the thermal insulation and durability of concrete and reduce the thermal cracking of concrete. The plant Fiber is used as a reinforcement in the concrete of the railway foundation, which can enhance its tensile strength, impact strength, and flexural strength. The optimal loading range is 0.6-0.9%, and the long Fiber lay-flat method is the best. In the mixed method, these five physical reverse effects can be prepared in the range of 1.2-2.0%. The single tensile squeezing capacity of 30 plants using the mixed method is up to 3.69 MPa, which is the only chemical evaluation capacity of 46.5%.

Study of the mechanical properties, durability, and microstructure of an ultra-high-performance fiber-reinforced concrete containing recycled fillers

Abstract In this article, a specific mix design of the ultrahigh-performance fiber-reinforced concrete (UHPFRC) was proposed and applied for Algerian materials that are currently in use. In the absence of a general mix design that limits their use and reuses waste materials, the present mix design can help reduce the high manufacturing cost of this type of concrete and make it more environmentally friendly. Here, we have looked for a reference mix design based on local ordinary aggregates, and then, we introduced the recycled fillers from ceramic waste and granulated blast furnace slag into our mix design, and we studied their effects on the properties of the fresh state (density, workability, and air content) and in the hardened state, namely compressive and flexural tensile strength, modulus of elasticity, ultrasonic and sclerometer resistance, as well as durability tests (capillary and immersion absorption, porosity, and chemical resistance). The microstructure analysis was carried out using scanning electron microscopy, complemented by energy-dispersive X-ray spectroscopy. Comparison of the results of UHPFRC using ceramic waste and slag fillers with the control UHPFRC after 28 days shows an increase in compressive strengths of approximately 8 and 7%, respectively, as well as an increase in flexural tensile strengths of 17 and 2%, respectively. In addition, there was a decrease in porosity of 17 and 42%, respectively. The results reveal that it is possible to produce UHPFRC based on local materials and improve its performance, durability, and microstructure with recycled fillers.

An experimental and numerical investigation of using palm oil fuel ash as a partial cement replacement in steel fiber-reinforced concrete

An experimental and numerical investigation of using palm oil fuel ash as a partial cement replacement in steel fiber-reinforced concrete

Metoda za postizanje značajnih sila sidrenja unutar ograničenih dubina ugradnje u tanke betonske ploče i ljuske ojačane vlaknima

Contemporary fibre-reinforced concrete provides new opportunities for the design of thin concrete elements with substantial bending strength. To realise the full benefits of reduced weights owing to the reduced structural thickness, new anchorage elements must be developed that can sustain high anchorage forces within limited embedment depths in thin plates. This paper introduces a new anchorage design for concrete plates or shells that provides high tensile forces between 4 and 6 kN within a small embedment depth of 5 mm. The proposed design concept includes a two-stage anchorage mechanism that provides the required tensile strength and ductility for the anchorage. Achieving such anchorage capabilities within the limited embedment depth of thin concrete elements enables the production of lightweight concrete plates and shells.

Experimental investigation of face mask fiber-reinforced fully recycled coarse aggregate concrete

To address the challenges associated with the disposal of construction and demolition waste (C&DW) and discarded personal protective equipment, this study investigates the feasibility of using face mask (FM) fibers to enhance fully recycled coarse aggregate (FRCA) concrete. The current study uses six FM fiber volume fractions (0, 0.1 %, 0.2 %, 0.3 %, 0.4 %, 0.5 %) for FRCA concrete reinforcement. According to the mechanical performance test results, adding FM fibers can enhance the splitting tensile strength (up to 8.22 % contents 0.1 % FM fiber) and flexural strength (up to 26.92 % contents 0.2 % FM fiber) of FRCA concrete. While excessive FM fibers (over 0.3 %) affect compressive strength negatively, the damaged concrete retains integrity due to the bridging action of FM fibers combined with scanning electron microscopy (SEM) analysis. Comparatively, the hydrophilic inner layer of disposable medical masks features a better microstructural fiber arrangement, increasing tensile strength by 14.51 % and 111.68 % compared to the filter and outer layers, respectively, making it ideal for enhancing FRCA concrete. All samples achieved a "Good" rating in the UPV tests, confirming the feasibility of FM fiber-reinforced FRCA concrete. The calculation method for FRCA concrete mechanical properties prediction considers the contribution of fibers in addressing the disparate effects of FM fiber incorporation, with correlation coefficients of 0.904 and 0.827 for splitting tensile strength and flexural strength, respectively. Environmental and economic impact analysis indicates that FM fiber-reinforced FRCA concrete can reduce carbon emissions by 71.25 % and save 29.05 % of economic costs.

Emerging eco-friendly fiber-reinforced concrete with shaped synthetic aggregates using Taguchi grey relational analysis and utility concept

The present study assessed the applicability of employing Taguchi-based Grey relational analysis (T-GRA) and the Taguchi approach combined with the utility concept (T-UC) for enhancing the mix design parameters of fiber-reinforced synthetic aggregate concrete (FRSAC). Cement was supplemented with binders such as ground granulated blast furnace slag (GGBFS), metakaolin (MK), and lime powder (LP). The optimized mix proportion of FRSAC was determined to enhance the fresh and mechanical performance. Furthermore, this investigation used two weighting approaches: equally weighted and maximum deviation methods. An established L16 (45) Taguchi orthogonal array was used with five different factors, namely, cement replacement (40 %, 50 %, 60 % and 70 %), binder content (B1, B2, B3, B4), water-to-cement ratio (0.31, 0.32, 0.33, 0.34), fiber dosage (0.1 %, 0.2 %, 0.3 % and 0.4 %), and synthetic aggregate replacement (25 %, 50 %, 75 %, and 100 %) were employed to design the experiments. Then, T-GRA and T-UC were used to determine the optimum mix proportions for five response parameters: workability, compressive strength, split tensile strength, elastic modulus, and impact ductility index. Results indicated that the two methods, GRA and UC, can be successfully integrated with the Taguchi method to derive the optimized FRSAC mixture. Confirmation experiments were performed after determining the optimum mix design parameters, including cement replacement of 60 %, binder content of B4, the water-to-cement ratio of 0.34, fiber dosage of 0.1 %, and synthetic aggregate replacement of 75 %. The optimum FRSAC mix was examined for its fresh (workability) and hardened (compressive strength, split tensile strength, elastic modulus, impact ductility index) properties.

Incorporation of Jute Fiber in Concrete: A Literature Review

Abstract: This systematic literature review delves into the incorporation of jute fiber as a reinforcement material in concrete, examining its benefits, challenges, and potential applications. Jute fiber, a natural and biodegradable material, presents an eco-friendly and cost-effective alternative to synthetic fibers commonly used in concrete reinforcement. The utilization of jute fibers in concrete not only enhances its mechanical properties but also promotes sustainable construction practices, addressing the growing need for environmentally responsible building materials. The review synthesizes existing research on the physical, mechanical, and durability properties of jute fiber-reinforced concrete (JFRC). It explores how the unique characteristics of jute fibers, such as their high tensile strength and low density, contribute to improved concrete performance, particularly in terms of tensile and flexural strength. The addition of jute fibers helps mitigate crack propagation and enhances the ductility of concrete, making it more resilient to dynamic loads. Despite these benefits, challenges such as the hydrophilic nature of jute fibers, which can lead to increased water absorption and potential durability issues, are also addressed. Various chemical treatments and surface modifications have been explored to improve the compatibility of jute fibers with the cement matrix and enhance the overall durability of JFRC

Shear strength and ductility of novel steel fibre-reinforced concrete dowel connections for composite beams

In this paper, a novel steel fibre-reinforced concrete (SFRC) dowel connection without traditional steel bar reinforcement is proposed for steel-concrete composite beams. Push-out tests on thirty-six specimens were conducted to investigate the shear strength and ductility of SFRC dowel connections with varying dowel sizes, concrete densities, fibre content and type. Even without the presence of reinforcing bars, the SFRC dowels were able to resist substantial loads and maintained a ductile load-slip behaviour. The shear strength of SFRC dowels increased with an increase in the fibre content, dowel size, and concrete density. Further, dowels with higher steel fibres content exhibited enhanced ductility, displaying a near elastic-plastic load-slip behaviour, with an ability to resist up to 80 % of the ultimate load even at 6 mm slip. A unique analytical model to predict the ultimate load and the load-slip curve is proposed in this study. The model was able to predict the ultimate load to within 6 % of test results, on average, while the mean load at 6 mm slip was predicted to within 3 % of the test results, with standard deviation of 17 % and 13 % respectively. The general shape of the load-slip curve was also well predicted. The study also proposes simplified equations, which predicted the shear strength of SFRC dowels to within 2 % of the test results with a standard deviation of 13 %.

Efficacy of PZT Sensors Network Different Configurations in Damage Detection of Fiber-Reinforced Concrete Prisms under Repeated Loading.

Real-time structural health monitoring (SHM) and accurate diagnosis of imminent damage are critical to ensure the structural safety of conventional reinforced concrete (RC) and fiber-reinforced concrete (FRC) structures. Implementations of a piezoelectric lead zirconate titanate (PZT) sensor network in the critical areas of structural members can identify the damage level. This study uses a recently developed PZT-enabled Electro-Mechanical Impedance (EMI)-based, real-time, wireless, and portable SHM and damage detection system in prismatic specimens subjected to flexural repeated loading plain concrete (PC) and FRC. Furthermore, this research examined the efficacy of the proposed SHM methodology for FRC cracking identification of the specimens at various loading levels with different sensor layouts. Additionally, damage quantification using values of statistical damage indices is included. For this reason, the well-known conventional static metric of the Root Mean Square Deviation (RMSD) and the Mean Absolute Percentage Deviation (MAPD) were used and compared. This paper addresses a reliable monitoring experimental methodology in FRC to diagnose damage and predict the forthcoming flexural failure at early damage stages, such as at the onset of cracking. Test results indicated that damage assessment is successfully achieved using RMSD and MAPD indices of a strategically placed network of PZT sensors. Furthermore, the Upper Control Limit (UCL) index was adopted as a threshold for further sifting the scalar damage indices. Additionally, the proposed PZT-enable SHM method for prompt damage level is first established, providing the relationship between the voltage frequency response of the 32 PZT sensors and the crack propagation of the FRC prisms due to the step-by-step increased imposed load. In conclusion, damage diagnosis through continuous monitoring of PZTs responses of FRC due to flexural loading is a quantitative, reliable, and promising application.

Carbon fiber and PVA fiber reinforced concrete: Electrical resistivity and piezoresistive properties

This study examines the effects of carbon fiber (CF) and polyvinyl alcohol fiber (PVAF) on the mechanical and electrical properties of fiber-reinforced concrete by using four-electrode system and piezoresistive testing platforms. The optimal combination of 0.6 % CF and 0.6 % PVAF significantly improved piezoresistive properties, with a 45 % increase in relative resistivity. Additionally, 0.6 % CF with 0.9 % PVAF achieved a 13 % boost in compressive strength. SEM analysis revealed enhanced interfacial bonding between fibers, leading to improved mechanical and electrical performance. These findings highlight the composite’s potential for structural health monitoring, electromagnetic shielding, and winter snow removal applications