Use Of Glass Fibers Research Articles

Moment Curvature and P-M Interaction Analysis of Steel and GFRP Reinforced Concrete Column

This research explores the use of Glass Fiber Reinforced Polymer (GFRP) bars and GFRP circular sections as longitudinal reinforcement in Reinforced Concrete (RC) columns, specifically to mitigate corrosion issues in harsh coastal environments. Twelve concrete specimens were prepared and tested under various loading conditions to evaluate the performance of GFRP as a substitute for conventional steel reinforcement. The experimental findings indicated that GFRP-RC columns displayed slightly lower axial load and bending moment capacities compared to steel-RC columns, though the ductility of both types was found to be similar. The study also highlights the significance of considering the role of GFRP bars in compression, supported by experimental results. This research offers valuable insights into the behavior and performance of both steel and GFRP-reinforced concrete columns, particularly in environments vulnerable to corrosion, with assessments conducted at 28 and 60-day intervals. A comparison of the outcomes from these timeframes reveals the effectiveness of GFRP as a reinforcement option in corrosive conditions

Post-fire performance of hybrid GFRP-steel reinforced concrete columns

The fire safety requirements and knowledge on the use of Glass Fiber Reinforced Polymer (GFRP) bars as an alternative to conventional steel in reinforced concrete structures have been progressively evolving. This study investigates the post-fire axial performance of square GFRP reinforced concrete (RC) columns, addressing a significant gap in current knowledge. Five column specimens of the same cross-section and length were tested, where the main parameters considered are the clear cover depths (40, 50, and 65 mm) and the use of a 40-mm insulation on one column. The columns were subjected to a long 3-hour fire exposure per ASTM E119 standard without sustained loading. The columns were tested upon cooling under concentric axial loading. Despite the notable temperature differences between columns with 40 and 65 mm concrete cover (300 and 500 °C after 3 hours), the post-fire residual axial capacity appeared unaffected. This is primarily attributed to the minimal differences in the retained mechanical properties of GFRP bars at temperatures exceeding 200 °C. The study's findings indicate that GFRP longitudinal bars do not significantly influence the performance of columns in fires. Consequently, future research should focus on columns reinforced with GFRP ties as well. The predicted values of post-fire axial capacity closely match the experimental data for non-insulated columns, indicating a high degree of accuracy. The study provides design recommendations to enhance the fire performance of such elements. The use of insulation results in a substantial reduction of temperature at various depths of the column. Post-fire residual capacities for non-insulated columns were approximately 30 %, whereas insulated columns demonstrated a 60 % residual capacity.

Comparison of mechanical behavior of slabs reinforced with GFRP and steel

The objective of this study is to evaluate the mechanical behavior of GRFP in massive concrete slabs. The use of glass fiber reinforced polymer (GFRP) rebars in construction design has been an alternative technique to provide more durable structures. However, there is a need to evaluate the behavior of GFRP reinforced slabs under flexure and to compare the service state (SS) and ultimate service state (USS) of the loaded element. Thus, reinforced concrete slabs of varying thicknesses were constructed with steel and GFRP rebars. Results show that the applied load for maximum span deflection of the GFRP slab under SS was 50% lower than for the one with steel reinforcement. The maximum span deflection of the GFRP slab under USS was also 282% larger than for steel rebars reinforcement.

Mechanical and fracture properties of mortars reinforced with glass fibre and prepared with different cement types

PurposeThe main aim of the current study is to investigate the effect of Anti-Crack HP 67/36 glass fibre on the mechanical performance of mortars made of cement, with a focus on post-cracking evaluations using the digital image correlation (DIC) technique.Design/methodology/approachExperimental tests were carried out on 36-mm long fibres at 0.8% by volume and added to the normal strength (NSM), high strength (HSM) and high strength mortar with fly ash (HSMFA) mortars. CEM I 52.5 CP2 NF, CEM II/A-L 42.5 NF and CEM III/C 32.5 N-SR PM were used for each series of mortar to assess the performance of the glass fibres with the types of cement. F-class fly (FA) ash was used to reduce global CO2 emissions.FindingsThe mortar’s strength decreased as the cement types changed from CEM I to CEM II and III. However, due to changes in the portlandite content of the cement, water porosity increased for both types of mortar, without and with fibre. It was also found that using glass fibre increased flexural strength more than compressive strength, regardless of the type of cement used. For all the strength classes, it was found that the mortar mixes with CEM I had the highest critical crack opening (wc) and fracture energy (GF), followed by CEM II and III. No significant effects were observed in the mortar’s property by replacing fly ash (12%).Research limitations/implicationsOnly mortars were formulated in this study, but the results must be verified at the concrete scale.Practical implicationsValidation of the DIC technique to characterize the post-cracking behaviour of cement-based material. Use of glass fibres to improve the material’s resistance to cracking.Social implicationsUse of CEM II and CEM III cements with low CO2 footprint instead of CEMI without altering the mechanical performance of the material.Originality/valueThe work is a further contribution to studying the cracking behaviour of several series of variable mortars depending on the resistance class and the type of cement used.

Evaluation of freeze-thaw resistance of geopolymer concrete incorporating GFRP waste powder

This study investigates the use of glass fiber reinforced polymer (GFRP) waste powder as a partial replacement for cementitious materials in the synthesis of geopolymer concretes (GPCs), focusing on their durability under freeze-thaw (F-T) conditions. Two types of binary GPCs were synthesized: GFRP powder/ground granulated blast furnace slag (GGBS)-based GPC and GFRP powder/fly ash (FA)-based GPC, with a GFRP powder weight content of 30 %. Single GFRP powder-based, GGBS-based and FA-based GPCs were prepared as reference materials. The F-T resistance was evaluated through mass loss and residual compressive strength (RCS), as well as examining the microstructure using scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP). Results demonstrated that the mass loss of all GPC samples remained below the critical value of 5 % after 300 cycles. The incorporation of 30 wt% GFRP powder into GGBS-based GPC resulted in improved resistance to F-T damage, increasing the number of cycles endured from 200 to 300. Similarly, adding 30 wt% GFRP powder to FA-based GPC demonstrated enhanced resistance to F-T deterioration, with the number of cycles increasing from 150 to 175. The pore distributions of GFRP powder/FA-based GPC remained relatively unchanged before 200 F-T cycles, indicating it effective resistance against F-T conditions. GFRP powder/GGBS-based GPC exhibited a more uniform and denser microstructure with a reduced presence of pores, even after enduring 300 F-T cycles, making it better equipped to withstand F-T cycles. Furthermore, prediction models were developed to estimate RCS and damage evolution due to F-T conditions, producing accurate results compared to test data. This study presents an effective method for the utilization of GFRP waste as a building material in cold environments.

Size effect on compressive behavior of GFRP bars

In the last three decades, studies investigating the use of Glass Fiber Reinforced Polymer (GFRP) bars as an alternative to conventional steel rebars have increased due to their corrosive resistance. In addition to corrosion resistance, GFRP bars utilize high specific tensile strength, which makes them highly desirable in civil engineering applications. However, major design guidelines for GFRP-reinforced concrete structures currently do not consider their compressive contribution. Nevertheless, there is a growing trend in utilizing GFRP bars as compressive elements, driven by various studies demonstrating their ability to bear compressive loads effectively. This increasing demand underscores the need to comprehend the mechanical properties of GFRP bars, particularly in terms of their compressive behavior. Furthermore, a standardized test method to evaluate their compressive properties has not yet been developed. Addressing these gaps, this research paper focuses on investigating the influence of specimen size on the compressive strength of GFRP bars, specifically emphasizing on the compressive properties of GFRP bars. Compressive tests were conducted on GFRP specimens with varying diameters while maintaining a constant slenderness ratio. The findings from these compression tests shed light on the critical role of size in the compressive behavior of GFRP. This research emphasizes the importance of considering size as a significant parameter in designing mechanical properties for GFRP reinforcements.

Wear behaviour of glass fiber reinforced polyester composites under dry friction and fluid film lubrication

Abstract The use of composite materials, which are more economical and have better material properties, has become widespread in the industry lately. The glass fiber reinforced polyester composite materials constitute majority of composite materials produced in industry. Wear reduces working life of machine parts, affects their functions, and causes undesired deterioration, resulting in part separation over the contact surface. The machine parts produced from glass fiber reinforced polyester composite materials wear out because of exposure to dry friction and fluid film lubrication under different operating conditions. In this study, wear behaviours of glass fiber reinforced polyester composite materials under dry friction and fluid film lubrication conditions were investigated. The various results were obtained with this study. The wear resistances of samples in dry friction and fluid film lubrication conditions are like each other. The use of glass fiber, glass bead and plasticizer tensile additive in glass fiber reinforced polyester composite specimens is effective in improving the wear resistance of specimens.

A Comparative Analysis of Steel Replacement with Glass Fiber Reinforced Polymer (GFRP) in Construction

The present study goal is to investigate the possible use of Glass Fiber Reinforced Polymer (GFRP) as an alternative to conventional Steel reinforcement in the construction sector through a comparative analysis. It offers important insights for decision-makers and building experts by concentrating on assessing structural performance, economic feasibility, and environmental sustainability. In the comparison analysis, Orion simulations with both steel and Glass Fiber Reinforced Polymer (GFRP) reinforcement for column and beam structures are used. The results emphasize the materials' notable distinctions from one another as well as their unique characteristics and implications for structural performance. According to the study, 4Y16 Glass Fiber Reinforced Polymer (GFRP) reinforcement offers improved tensile strength and corrosion resistance, making it a competitive substitute for 4Y12 Steel, which is the standard strength for column structures. The recommended usage of 3Y10 Glass Fiber Reinforced Polymer (GFRP) in beam structures rather than 3Y12 Steel emphasizes how crucial it is to balance weight reduction without sacrificing the ability to support loads. The research does, however, admit several of the models' shortcomings, including the assumptions of constant loading conditions and the omission of elements like cost and ongoing maintenance. The economic analysis, which is based on information taken from the summary sheet of the Orion software, demonstrates the significant cost differences between the reinforcement made of Steel and Glass Fiber Reinforced Polymer (GFRP). The significant cost difference between Glass Fiber Reinforced Polymer (GFRP) and typical Steel reinforcement makes Glass Fiber Reinforced Polymer (GFRP) a more financially attractive option, which could lead to significant construction cost savings.

Mechanical and Thermal Characteristics of Concrete Reinforced with Crushed Glass and Glass Fiber: An Experimental Study

The incorporation of waste glass and glass fiber, as replacements for fine aggregate and cement respectively, offers a sustainable strategy to mitigate landfilling and virgin aggregate extraction. The present study delves into the influence of these waste derivatives on the mechanical and thermal attributes of concrete. Fine aggregate was substituted by crushed glass shards in a weight-to-weight ratio ranging from 5% to 30%, and cement was replaced by glass fiber in a weight-to-weight ratio of 1%. Mechanical attributes such as compressive, flexural, and splitting strength were evaluated, along with thermal characteristics of the concrete. A concrete mix ratio of 1:2:4 and a water/cement ratio of 0.45 were employed. The results revealed that concrete designated as Mcf20% demonstrated superior mechanical properties compared to the reference concrete. After 28 days, compressive strength of 51.2 MPa, flexural strength of 6.5 MPa, and splitting tensile strength of 3.78 MPa were recorded for Mcf20% concrete, signifying the beneficial effects of the combined use of glass fiber and crushed glass. Furthermore, an inverse relationship was observed between the percentage of waste additives and thermal conductivity. This investigation underscores the potential of recycling glass and glass fiber as eco-friendly additives in concrete, improving both mechanical properties and thermal performance, thus endorsing their use in structural and architectural concrete applications.

Mechanical Properties of Stone Mastic Asphalt Incorporating Glass Fiber

Aims: To study the mechanical properties of stone mastic asphalt incorporating glass fiber. Background: Asphalt may become cracked, degraded, or otherwise flawed because of the combination of SMA surfaces and general degradation. SMA, when combined with glass fibre, has the potential to bring about advancements in the road industry. Objective: The use of glass fibres to enhance the mechanical characteristics of Stone Mastic Asphalt. Methods: Marshall stability test, Resilient modulus test, Dynamic creep test, and Abrasion test. Results: The presence of fibre may increase the performance of the apparent Stone Mastic Asphalt, and a composition including 3 percent glass fibre results in improved stability and stiffness. Conclusion: A quantity of glass fibre equal to three percent is the optimal proportion to be used in the process of increasing the mechanical characteristics of SMA. The performance of glass fibres with a lower volume per unit is better than those with the largest volume per unit.

Experimental and numerical investigation of flexural behaviour of concrete beams reinforced with GFRP bars

To solve the issue of corrosion, the use of glass fibre reinforced polymer (GFRP) bars in reinforced concrete (RC) has emerged as a feasible option for conventional steel bar RC. Given that GFRP RC beams have different mechanical properties and behaviours than steel counterparts, a thorough investigation of the load–deflection behaviour, failure modes, and overall performance of GFRP RC beams via experimental, analytical, and numerical studies is required. Therefore, this study encompasses the experimental, analytical, and numerical investigation of GFRP RC beams. Total of 9 beams are experimentally investigated, three (3) reinforced with steel bars (10 mm dia) while six (6) reinforced with GFRP bars (10 mm and 16 mm dia). Experimental results reveal that GFRP RC beams exhibit lower load carrying capacity and more deflection than their steel equivalents, respectively. GFRP RC beams have a 32.4 % lower ultimate load and a 16 % higher ultimate deflection than steel RC beams for the same reinforcing ratio. Steel RC beams failed under tension control, whereas GFRP RC beams failed under compression control. Analytical models, primarily based on effective flexural stiffness, are used to predict the load–deflection behaviour of GFRP RC beams. Nonlinear numerical modelling of GFRP RC beams is carried out using ATENA 2D. The load–deflection responses obtained from analytical and numerical studies are compared with experimental results and found to be in good agreement. After the validation of numerical models, the behaviour of GFRP RC beams has been investigated using a thorough parametric research, which looked at the impact of concrete compressive strength, longitudinal reinforcement ratio, GFRP bar elasticity modulus, and shear span to depth ratio.

Predicting the Bond Resistance of Glass Fiber Bars in Hinged Beams Employing Enhanced Soft Computing Techniques

One of the principal parameters which affect the behavior of reinforced concrete (RC) elements is the bond of the bar to concrete. Considering the corrosion of steel bars and the widespread use of glass fiber reinforced polymer (GFRP) bars, it is necessary to study the bond between concrete and GFRP rebars. The hinged beam is one of the tests which simulates the relatively actual stress of RC members. In this study, a database containing 116 GFRP reinforced hinged beams with pull-out failure mode has been collected. To predict the bond resistance, Kriging, multivariate adaptive regression splines (MARS), and nonlinear regression techniques are utilized. K-fold cross-validation, sensitivity analysis of input variables, and optimization of tuning parameters for soft computing methods have been used to increase the precision, efficiency, and generality of the proposed models. Also, using the nonlinear regression method, a practical and straightforward relationship is suggested to forecast the bond resistance. The proposed Kriging, MARS, and nonlinear regression models outperformed the other models with determination coefficients of 0.98, 0.96, and 0.78, respectively. Parametric analysis of the variables has also been performed to investigate the influence of various input parameters on the bond resistance of GFRP bars in hinged beams.

Experimental study on strength comparison of the glass fiber reinforced concrete (GFRC) and conventional concrete (M30 grade)

This is a comparatively recent advancement in construction technology. This saves money in the construction process because it is light weight. The use of glass fiber to replace steel in reinforced concrete structures helps reduce corrosion and structural damage. Many alternatives have been investigated to increase concrete’s strength, durability, shrinkage characteristics, and serviceability while considering global environmental factors. As a consequence, glass fiber has been employed as an additive, and trials with various percentages of 1%, 2 %, and 3% cement have been carried out. When considering this material, concepts such as glass fiber, light weight, cost-effective, ecologically friendly, and compressive strength must be considered. GFRC is a cement matrix made up of cement, sand, water and admixtures, and contains short glass fibers. Facade panels, pipes and channels are examples of non-structural elements that have been extensively used. Light weight (which lowers dead load), fire resistance, an attractive appearance, and tensile strength are just a few of the benefits of GFRC. Trial tests for concrete with and without glass fiber are conducted using cubes, beams, and cylinders to measure the differences in compressive strength, flexural strength, and split tensile strength. Because glass fiber may be molded and sculpted in a number of ways, its demand is growing in India due to rising building activity and other causes. Compared to other reinforcing materials, it is a more affordable and cost-effective solution.

Performance evaluation of silty soil reinforced with glass fiber and cement kiln dust for subgrade applications

In this study, the use of glass fiber and cement kiln dust (CKD) as stabilizing agents for a typical silty soil is investigated. Fibers with three lengths (12 mm, 18 mm and 24 mm) were added as percentages of soil’s dry weight (0.3%, 0.6%, 0.9%, and 1.2%), the cement kiln dust (CKD) was added in three percentages by dry weight of soil (7%, 14% and 21%). The subgrade strength was evaluated in terms of laboratory California bearing ratio (CBR) tests in soaked and unsoaked environment to simulate both dry and inundated conditions for field applications. Chemical and microstructural changes were monitored with Fourier transform infrared spectroscopy (FTIR) and integrated FESEM-EDAX analysis respectively. IITPAVE software was used to compute actual strains on pavement layers and determine the optimum thickness of the pavement sections for untreated and treated subgrade. In comparison to the untreated soil, the overall pavement thickness reduced by approximately 44% when designed on improved subgrade. The cost reduction, using the improved subgrade material was approximately 37.5%. Because the actual strains were significantly lesser than the permissible values, the structural performance of the pavement designed on improved subgrade was enhanced against subgrade rutting and fatigue cracking. The optimum CKD–fiber combination was found to be 14% CKD and 0.6% fiber. The laboratory test results indicated that the proposed ground improvement technique can be effective for subgrade improvement of low-volume roads and also serve as a sustainable disposal solution of CKD.

Tam Faktöriyel Tasarım Kullanılarak Çimento Harçlarında Cam Atıklarının Kullanımının İncelenmesi

Waste management in the world has come to the fore in recent years. Like many materials used as alternative raw materials, glass waste has become an increasingly important situation. It is very important in terms of sustainability that these wastes are used as alternative raw materials in the production of new materials for various industries. Recycling of glass, which is produced and consumed in a wide range, contributes to many different sectors. For this purpose, the use of materials obtained in two different forms, namely powder and fiber produced from waste glass, in cement mortars was investigated. There are three factors, including glass powder (GP) amount with four levels of 0, 45, 90 and 135 g, glass fiber (GF) amount with two levels of 0 and 13.37 g, and curing period (CP) with three levels of 7, 28 and 56 days. Compressive, flexural strengths and abrasion resistance of cement mortar samples were determined. In addition, acceptable regression models were derived by using multiple regression analysis. Analysis of variance (ANOVA) showed that the effects of all three factors on the mechanical properties and, GP and CP factors on abrasion resistance of cement mortars are significant. Improvements in mechanical strength and abrasion resistance were observed in the use of glass fiber and glass powder added cement mortars produced at appropriate rates. The study shows that the use of glass fiber and glass powder separately or together in the production of cement-based materials such as concrete, which is exposed to abrasion, is beneficial. As a result, the properties expected from the produced concrete will be met. The use of glass waste will contribute to the realization of an economical and environmentally friendly concrete production.

Shear-transfer mechanisms in reinforced concrete beams with GFRP bars and basalt fibers

An increase in the use of glass fiber reinforced polymer (GFRP) bars and discrete fibers in reinforced concrete structures, associated with the limited understanding of the shear behavior of concrete beams, highlights the need for a comprehensive study of various force transfer mechanisms. This article investigates the experimental behavior of four slender reinforced concrete beams with GFRP bars. The testing program includes beams with and without GFRP stirrups and dispersed basalt fibers in the concrete matrix. The displacement fields throughout the shear span were monitored according to the digital image correlation (DIC) technique and shear-transfer constitutive models from the literature assessed the contribution of each mechanism. The sum of such contributions consistently agreed with the experimental shear strength and the use of fibers in beams with GFRP stirrups modified the relative influence of both shear reinforcements, i.e., one of them can preponderate over the other in function of load stage and failure mode.

THE EFFECT OF ADHESIVE TYPE AND REINFORCEMENT TYPE ON FLEXURAL DEFORMATION OF BENDING LVL

In this study, the effect of reinforcement type and glue type on the amount of flexural deformation of reinforced bending LVLs was investigated. Within the scope of the study, 2.2mm peeled poplar veneer and 1.5mm peeled alder veneer were used as wood material. Glass fiber and basalt fabric (200g/m²) were used as reinforcement. Alder veneer was used on the lower and upper surfaces, and poplar veneer was used on the middle layers. Reinforcement material was applied to the convex surface of the bending LVL. A total of 7 different combinations of bending LVLs in the form of chair leg-armrest were produced. Flexural test, tensile test and ANSYS analysis were performed on the produced LVLs. According to the test results, it was determined that there was a decrease in flexural deformation with the use of reinforcement. It was determined that the best results were obtained with the use of glass fiber and epoxy. In addition, ANSYS results and real test results were found to be similar.

Research of technical characteristics of glass-fiber concrete

The article examines the technical characteristics of glass fiber reinforced concrete based on experimental research and selection of the optimal composition of fiber reinforced concrete. When selecting the composition, various technologies for introducing fibers, the percentage of fibers introduced, and the characteristics of the sand used were analyzed. The obtained research results allow us to determine the effectiveness of the use of glass fiber reinforced concrete structures in the reconstruction of buildings and structures. In the manufacture of test samples, materials of domestic production were used.

Delamination Depth Evaluation in Near-Surface of GFRP Laminates Based on RQA-MKLSVM Model

The increasing use of glass fiber reinforced polymer (GFRP) laminates in aircraft creates an urgent demand for nondestructive testing to identify defects such as impact damage and delamination in the materials’ near-surface structure. The High-frequency ultrasonic technique is an effective nondestructive testing technique capable of detecting such defects. However, with the increased delamination depth, it is difficult to accurately characterize the delamination defects in GFRP laminates by traditional characterization methods. And the conventional defect depth detection method takes much time and requires professional discrimination, which is easily affected by the level of inspectors and subjective factors. To address the issue of inaccurate feature extraction and low detection efficiency, we propose a new method for delamination depth recognition in the near-surface of GFRP laminates based on the RQA-MKLSVM model by combining the recurrence quantitative analysis (RQA) feature extraction method with the multi-kernel learning SVM technique to improve the capability of detecting delamination defects on GFRP laminates. Additionally, an image-enhanced method based on the nonlinear transformation function and wavelet multiscale product is used to locate the delaminated areas. Results show that the proposed method achieves accurate recognition of different delamination defects within depths ranging from 0.8 mm to 4.0 mm, and the average recognition rate has reached 95.63%. Compared with the training models based on discrete wavelet transform(DWT) and empirical mode decomposition (EMD), the recognition rate of our method is improved by 6.25% and 4.38%, respectively. And Compared with the two single-core models, the recognition accuracy of our method is improved by 8.55% and 5.00%, respectively.

Shear Behavior of Hollow Ferrocement Beam Reinforced by Steel and Fiberglass Meshes

The purpose of this study is to investigate the shear behavior of hollow ferrocement beams of self-compacting mortar reinforced with various types of metallic (steel wire mesh) and non-metallic (fiber glass mesh) reinforcement. The experimental program consists of casting eight ferrocement beams with dimensions of 150×225×2000 mm, with 50 mm of ferrocement thickness and a polystyrene cork core of 50×125 mm. The study parameters were the type of shear reinforcement and the number of layers of wire mesh. The results showed that the ultimate load of the beams reinforced with several layers of the fiber glass mesh (1, 2, and 3) was decreased by (3.27%, 16.52%, and 9.38%) respectively, compared to the beams reinforced with layers of steel wire mesh (1, 2 and 3). The ultimate load of these beams increased by (33.71%, 73.28%, and 122.11%) respectively, compared to the beams without shear reinforcement. Also, the ultimate load of the beams reinforced with layers of welded wire mesh was increased by (38.23%, 107.56%, and 145.09%) respectively, compared to the beams without shear reinforcement. The ductility and toughness of the beams reinforced with several layers of the fiber glass mesh (1, 2, and three) were decreased by (1.68%, 2.11%, 2.68%) and (29.39%, 25.91%, 16.06%) respectively, compared to beams reinforced with several layers of steel wire mesh (1, 2 and 3). The crack propagation was reduced and its number and crack width decreased by using steel wire mesh and fiber glass wire mesh instead of stirrups, especially in beams with two and three layers of wire mesh. The results also showed that the use of glass fiber or welded wire mesh in the reinforcement of hollow beams instead of steel stirrups has a significant effect on the failure load, deflections, crack patterns, and shear stresses, despite the clear preference for beams reinforced with steel wire mesh.