Glass Fiber Composites Research Articles

Synergy in bio-inspired hybrid composites with hierarchically structured fibrous reinforcements

In response to the global energy crisis, high-performance transportation sectors are rapidly embracing lightweight materials to enhance energy efficiency and sustainability, while grappling with the persistent challenges of developing structural materials that meet stringent safety standards with robust mechanical performance and ease of scalability. Thus, this work presents a combined experimental and theoretical framework to develop a profound understanding of the synergistic effect in hybrid composites with bio-inspired fibrous reinforcements, by elucidating the interfacial interactions across multiple length-scales, encompassing atomic covalent bonding to micro-morphology. A model hybrid composite system, containing a self-assembled fibrous reinforcement consisting of nano-sized Graphene Nanoplatelets (GnP) covalently bonded onto chemically-modified micro-sized Glass Fibers (GF), was utilized to showcase the synergistic effect and highlight its associated mechanisms. The interfacial interactions of the reinforcement were optimized by obtaining the maximum density of covalent bonds, which was achieved with 0.5 wt% GnP for the hybrid composites containing 10 wt% GF, increasing the work of adhesion by 33 %, compared to the biphasic GF composites. The composite’s morphology contains minimal agglomeration with ∼68 % of GnPs oriented with the melt flow, supressing high-stress concentration areas, while the formed crystalline microstructure, with ∼18 % β-crystals, allows the matrix to absorb substantial energy. Furthermore, the increased trans-crystallization encapsulating the hierarchical reinforcement induced nanoscale stiffness variations, increasing rigidity, and forming an ∼16 µm gradient interphase that facilitates load transfer. The greatest synergistic effect observed was ∼54 %, ∼37 %, and ∼75 % for the tensile modulus, tensile strength, and impact strength, respectively. Additionally, a theoretical framework accounting for the synergistic effect was formulated, using a two-step core/shell homogenization model, which shows great potential in expediting the design and optimization of innovative hybrid composite materials.

An experimental investigation to predict the durability of polyester-glass fiber composite subjected to tensile loading

Glass Fiber and resin composites represent a significant advance in the industry thanks to their lightness, strength, and versatility. Their mechanical strength, highlighting a number of critical aspects in the development of high-performance materials, opens up new prospects in sectors as diverse as aerospace, automotive, and construction, among others. These advances stimulate ongoing research and development in the field of composite materials, underlining the importance of these efforts in meeting future needs in terms of materials performance and durability. This study examines the capacity to predict the durability of polyester-glass fiber composites when subjected to tensile loading. The experimental approach involves exploring the mechanical properties of the composite material and changes in glass fiber content, fiber length, and plate thickness. The process includes performing tensile tests on composite specimens to assess characteristics like Young's modulus and fracture stress. The study uses analytical prediction tools, precisely the Monte Carlo approach, to evaluate the damage distribution within the composite material. The study emphasizes the substantial influence of glass fiber content with a maximum content of 60% mass resin and length with the optimum size of 60 mm on the mechanical properties where Young's modulus attains a value of 4 GPa and longevity of the composite. The study highlights the significance of plate thickness in improving structural performance and fracture toughness, where Young's modulus shows consistency across varying thicknesses. In contrast, stress shows an increasing trend with thickness, culminating in a value of 3.4 MPa. The results enhance comprehension of polyester-glass fiber composites' mechanical characteristics and prediction ability under tensile stress.

Structural integrity of glass fiber reinforced nanocomposites under hydrothermal aging for offshore structure applications

Glass fiber composites are widely used in offshore structures for marine application due to their exceptional strength-to-weight ratio, corrosion resistance, and durability. As offshore structures are exposed to harsh environmental conditions, including saltwater, fluctuating temperatures, and hydrothermal influences, understanding the effects of aging on structural integrity on glass fiber composites becomes very important. In this study glass fiber-reinforced epoxy nanocomposites with 1 % and 2 % nano Al2O3 reinforcement were produced using the vacuum-assisted resin transfer molding. These composites were subjected to a three-month aging process in artificial seawater at a temperature of 70 °C. Mechanical properties were assessed through Tensile and Flexural Tests, while thermal properties were analyzed via TGA, DTA, and DSC analysis. To examine the structural characteristics, Fourier Transform Infrared (FT-IR) spectrophotometry was utilized, and SEM analysis was conducted. Wear properties were evaluated through dry sliding wear tests. Water absorption properties were determined in a precisely controlled seawater bath. The findings reveal that the incorporation of 1 % nano Al2O3 effectively diminishes the water absorption rate, thereby safeguarding the mechanical, thermal, and structural properties within a hydrothermal environment.

Temperature-dependent calibration and temperature compensation of elastic shape-memory alloy strain sensors for fiber-reinforced composite applications

Abstract Strain sensors for fiber-reinforced plastics require higher elasticity and fatigue resistance than conventional strain gauges. Elastic strain sensors made of shape-memory alloys (SMA) meet this requirement. Due to greater elasticity, other procedures are required for their calibration than those recommended in standards. This paper presents a calibration method for shape-memory strain sensors as a function of ambient temperature and methods for temperature compensation are investigated. SMA strain sensors are manufactured as sensor patches from wire and layers of glass fiber fleece infiltrated with epoxy resin. The patches are bonded to bending specimens made of glass-fiber plastic composites. The calibration of the SMA sensors is implemented by means of a 4-point bending test using a self-built test stand. This is designed for operation in a climate chamber. The results show successful proof of feasibility of temperature compensation. The variation of the sensor signal in the unloaded state in the temperature response is less than 0.4 mV/V. The gauge factor depends on the temperature and is compensated by means of a regression with temperature sensor data. In combination with a temperature sensor, an almost complete compensation of the temperature-dependent behaviour is possible. A procedure is realised for calibrating SMA sensors at larger strains.

Mechanical Properties Characterization of Glass/Carbon Fiber Hybrid Multilayer Composite under Environmental Aging Condition

Metallic components in boating industry are being replaced with carbon fiber composites due to their light weight, excellent mechanical properties, and corrosion resistance. However, the carbon fiber cost has obstructed the substitution. Hybridization is suggested to merge carbon and glass fibers in cost-effective composites while maintaining the desired engineering properties. This study experimentally examines the impact of hybridization and seawater aging on the mechanical properties of glass and carbon fibers hybrid composites. A range of composites ([C]6, [CGC]s, [C]3[G]3, [GCG]s, and [G]6) are fabricated and aged in simulated seawater solution before their tensile, flexural, impact, and hardness properties are examined. The results revealed degradation in properties due to the ageing, the degree of degradation is influenced by the s hybridization configuration. The [G]6 sample shows the highest tensile strength reduction of 30% compared to 20% for the [C]6. The remaining samples exhibit reduction percentages falling between these two extremes. A similar behavior is observed in the flexural test, though the extremes values are smaller, 10.2%, and 12.5%. The impact and hardness tests showed an inverse relationship between the glass fiber content and impact strength degradation due to aging, while they exhibited a linear correlation for hardness degradation due to ageing.

Effects of TiO2 on fiber spinnability, structure, and mechanical properties of glasses derived from simulated lunar soils

The construction of lunar stations for research and habitation requires high-performance building materials that can adapt to the harsh lunar environment. One of the feasible building materials is fiber-reinforced composites, for which the composition of glass fibers can be designed like lunar soils, i.e., terrestrial basalt, and in turn the “lunar glass” can be drawn into fibers. Because of a wide variation of TiO2 in lunar soils, our study focused on a series investigation on the effect of TiO2 (0.55 wt%-6.14 wt%) on fiber spinnability and strength of the simulated “lunar glass and glass fibers”. The baseline glass composition was derived from a simulated TiO2-lean lunar soil and other glasses were made at different TiO2 doping levels. The addition of TiO2 was found to reduce the thermal stability of the melt, there appears a TiO2 threshold (6.14 wt%), at which fibers cannot be drawn without breakage because of melt devitrification. The fiber tensile strength exhibits a nonlinear characteristic with an apparent maximum at 1.52 wt% TiO2. FTIR and Raman spectroscopic studies were carried out to investigate the glass network structure responses to TiO2 modifications and show TiO2 functions as a network modifier, depolymerizing the silicate network. Statistical structure (FTIR & Raman based)–property modeling was attempted to further elucidate the effect of TiO2-induced structure change on Tg and fiber tensile strength. Good agreements were found between the model predictions and the measured values.

A comparative analysis of acoustic emission sensor embedding in glass fibre composite

The manufacturing process of composite structures permits fully embedding acoustic emission (AE) sensors. While the embedding process may pose challenges, its advantages, if proven, can outweigh the challenges. The increased sensitivity resulting from embedding acoustic emission sensors in composites is still not definitively established. A test was set up with pre-determined AE initiation locations (surface and sub-surface) and pre-determined receiving sensor's location (surface and sub-surface) to ensure any sensitivity increase was evident. The receiving sensor's attenuation along (at 90°) and across the fibres (at 45°) was assessed using two test methods: pencil lead breaking (PLB) and actuator methods. The actuator method involved using two pulse generators, the TGP110 pulse generator and the Mistras FieldCal. A range of specific frequencies were utilised, 30, 60, 150 and 300 kHz, using the FieldCal. The results obtained from the test methods were not in agreement with each other. For example, comparing the sensitivity using surface cracks, the PLB method showed decreased sensitivity when embedding the receiving sensor compared to the actuator method, which demonstrated minimal changes in sensitivity. The research aims to clarify the sensitivity increase obtained when embedding an AE sensor while taking into account the crack's position and frequency.

Assessment of damping and flexural behaviour of hybrid fibre-particulate composites

Hybrid composites are an advanced solution that offers multifunctional capabilities, including exceptional strength-to-weight ratios, vibrational damping and impact absorption. This work describes the damping capacity and flexural behaviour of a hybrid fibrous-particulate system composed of glass/carbon fabrics and three distinct micro-inclusions: silica particles, carbon waste microfibres, and cement. A statistical methodology based on the full factorial design is applied to identify the effects of fibre stacking sequence, including carbon-C5, glass-G5, C2G3, G3C2, GCGCG and CG3C, microparticle inclusions and matrix/fibre volume fraction (40/60 and 60/40) on damping and bending responses. A non-linear finite element (FE) analysis is conducted to explore the stress distribution based on the stacking sequence and predict the failure mechanisms of the hybrid laminate. The results indicate significant interaction effects, with hybrid architectures showcasing approximately 33% higher performance compared to glass fibre composites. A greater dependence on the fibre layup sequence is found for the damping factor, flexural modulus and strength. Notably, the incorporation of silica microparticles leads to an increase in flexural strength. Furthermore, a greater volume fraction of the matrix phase enhances the rheological efficiency in terms of the fibre-particle interface. Carbon fibre layers placed symmetrically on both beam sides (CG3C) and bottom layers (G3C2) significantly enhance the bending performance of hybrid composites.

Effect fiber length on mechanical and thermal properties of glass fiber reinforced polyphenylene sulfide composite

Polyphenylene sulfide (PPS) finds extensive applications in the automotive industry, aerospace electrical, and electronic components, as well as mechanical applications. In order to enhance the toughness and strength of PPS, this study employed long glass fibers as reinforcement material and prepared glass fiber-reinforced polyphenylene sulfide composites (PPS/GF) using melt blending method. Based on fiber length distribution (FLD), this study comparatively analyzed the mechanical and thermal properties of short-cut glass fiber (PPS/SGF3mm) and continuous glass fiber (PPS/LGF) composites. Experimental results demonstrated that with a 5.45% increase in critical fiber length fraction, the tensile strength of PPS/LGF composites exhibited a significant improvement of 11.25%–13.6% compared to PPS/SGF3mm composites. Furthermore, FLD had minimal influence on the thermal stability of the composites, but exerted a significant impact on the crystallization behavior, whereby LGF led to a significant reduction in the crystallinity of PPS composites. These findings suggest that the utilization of continuous glass fibers enables the development of cost-effective and robust PPS composites, meeting the requirements of high strength and high temperature resistance in engineering applications. This study provides valuable insights for material selection and design.

In vivo evaluation of a polyester and fiberglass composite intramedullary nail for femoral osteosynthesis in calves.

The objective of this study was to test a composite of polyester resin and fiberglass in the form of an intramedullary nail for osteosynthesis of femoral fractures in calves. The methodology was established based on a previous study that used a bovine femur finite element model to simulate fractures, which were then stabilized by the same nails as proposed in this study. General anesthesia was induced in six calves followed by fracture creation via an oblique incision in the middle third of the femoral diaphysis, and osteosynthesis was immediately performed by retrograde insertion of the composite nail. Locking was achieved by drilling the bone and nail without using a jig and introducing two stainless steel screws proximal and two distal to the fracture line. Five of the six calves achieved complete fracture healing after 60 days. No signs of incompatibility or toxicity of the composite were observed. However, limitations were observed during the surgery, such as difficulty in drilling the nail and trimming the remainder portion of the nail that extended beyond the length of the bone. Small fragments produced by these maneuvers were considered irritating to soft tissues during the postoperative period. It was also found that small cracks in the nail tended to propagate in the form of longitudinal fractures. In conclusion, an intramedullary nail made of polyester resin and fiberglass (a low-cost and easy-to-acquire material) was considered biocompatible and capable of allowing bone healing of femoral fractures in young cattle. However, the development of solutions for the reported limitations is crucial prior to recommending the proposed composite for clinical use.

Investigation on the elimination of striations in NDE of glass fiber composites

Glass fiber composites are widely used due to their unique performance advantages. However, defects in glass fiber composites can significantly affect their performance, making nondestructive evaluation necessary. During the X-ray spectral imaging of glass fiber composites, the 0/90° cross-stacking mode of glass fiber cloth results in irregular horizontal and vertical stripe noise, which seriously reduces the clarity of defect detection. Therefore, an appropriate algorithm is required to remove the noise. In this study, by analyzing the Fourier spectrum of X-ray spectral images of glass fiber composites, it was found that the stripe information is concealed in the vertical and horizontal bright lines in the middle of the Fourier spectrum image. A novel cross-sector filter was designed, and a stripe noise removal algorithm based on the cross-sector filter was proposed. The degree of the filter’s central angle can be adjusted according to the distribution of the stripe noise in the frequency domain, which removes the noise without losing much useful image information.

Comparative Evaluation of Different Post and Core Systems in Maxillary Molar Endodontic Treatments: An Original Study.

Maxillary molar endodontic treatments require the right post and core system. This study tested cast metal, glass fiber with composite resin, carbon fiber with composite resin, and zirconia post and core materials. Sixty removed human maxillary teeth were randomly divided into four post and core material groups (n = 15 per group). The teeth acquired their post and core system after normal endodontic treatment. Fracture resistance, cyclic fatigue resistance, and microleakage analyses were statistically assessed. The zirconia post and core material had the highest fracture resistance (mean: 900 N), followed by carbon fiber with composite resin, cast metal, and glass fiber with composite resin. Zirconia had the highest mean cycles to failure (120,000), followed by carbon fiber with composite resin (100,000), cast metal (110,000), and glass fiber with composite resin (90,000). Zirconia had the lowest mean microleakage score (1.8), and glass fiber with composite resin, the highest (3.0). The zirconia post and core material outperformed the others in fracture resistance, cyclic fatigue resistance, and sealing. The cast metal has better fracture and cycle fatigue resistance than glass fiber with composite resin. These findings help doctors choose maxillary molar endodontic post and core materials.

Mechanical and thermal properties of short banana fiber reinforced polyoxymethylene composite materials dependent on alkali treatment

Abstract The present study aimed to develop a recyclable composite material based on a natural product, namely banana fiber, instead of synthetic reinforcement elements such as glass fiber or carbon fiber in thermoplastic matrix composites employed in many aspects of daily life. Polyoxymethylene (POM) thermoplastic was used as the matrix material. 3 %, 6 %, and 9 % by weight short natural banana fiber was used as reinforcement. Furthermore, the study improved the mechanical and thermal properties of the composite material with chemical improvements based on alkali treatment of banana fiber. Banana fiber and POM was initially mixed mechanically and then extruded at temperatures between 170 and 190 °C to obtain a homogeneous mixture. The mixture obtained by extrusion was initially cooled in the cooling pool and then passed through the crusher to obtain granules. These granules were pressed in plastic injection molds to obtain standard test samples. The ratio of reinforcement material and the variations in mechanical and thermal properties of the composites induced by the alkali treatment are presented in figures and tables. Furthermore, the changes in cross-sectional material images were examined with electron microscopy scans. The tensile and flexural strength of the material improved with alkali treatment.

Adhesive bonding of glass-fibre thermoplastic composite: process optimisation and sustainability analysis using LCA methodology

In recent years, great attention has been paid to the challenge of integrating more sustainable circular approaches to manufacturing, which involve optimising the entire product cycle, from design to fabrication, assembly and eventual reuse/recycling. In this context, the use of thermoplastic composite materials in combination with adhesive bonding is attracting increasing attention to achieve this dual objective. Therefore, the proposed research focuses on the experimental and statistical optimisation of an adhesive bonding process for glass-fibre–reinforced composite substrates with polypropylene matrix, with the aim of comparing its performance with that of joints made using more conventional configurations, i.e. utilising thermosetting substrates. A low-pressure plasma pre-bonding surface treatment is adopted, and its effectiveness in enhancing joint performance compared to more conventional preparations for plastics is discussed. By varying plasma parameters according to the design of experiments statistical approach, the joint response is studied in terms of tensile shear strength and modelled in accordance with the response surface methodology to identify the optimum condition of process parameters within the established system boundaries. The study found that with optimised pre-treatment, adhesive joints of glass-fibre–reinforced composites with thermoplastic matrices (first scenario) can achieve tensile shear strength (TSS) comparable to that of thermoset composites (second scenario), making them viable options in various applications. Two alternative scenarios—namely, joints with thermoplastic composite or thermoset composite substrates—are then analysed by the life cycle assessment methodology and compared according to their relative environmental impact, demonstrating that glass-fibre thermoplastic composite joints are competitive alternatives to thermoset joints in terms of mechanical static performance achieved, but significantly preferable with regard to environmental sustainability.

Comparative study of the mechanical properties of glass and Kevlar fiber-reinforced honeycomb composite

Honeycomb sandwich structures have wide range of applications in the aircraft, automobile, and satellite sectors due to their superior properties such as high specific strength, stiffness, energy absorption, and high impact strength. In this study, mechanical characteristics such as compression, three-point bending, and in-plane impact properties of 3D woven honeycomb composites produced from Kevlar and glass fiber were investigated. The focus of this research is to compare the mechanical performance of woven honeycomb composites developed from these two fibers with similar cell structures. The results revealed that Kevlar fiber honeycomb composite shows higher peak load and energy absorption for flatwise and edgewise compression while in three-point bending and in-plane impact, glass fiber honeycomb composite shows higher peak load, and impact energy absorption. The deformations shown in all the mechanical properties give the ductile behavior for Kevlar fiber and brittle behavior for glass fiber composite. The findings of the study suggest that the failure modes are mostly determined by the nature of the material itself.

Glass Fibre Composites Recycling Using the Fluidised Bed: A Comparative Study into the Carbon Footprint in the UK

The UK has no established process for recycling waste glass fibre-reinforced thermosets that are widely used within wind blade structures. Consequently, these materials are typically disposed of in landfills or undergo energy recovery in waste facilities. This study investigates the carbon footprint of the fluidised bed process for recycling glass fibre composite waste, considering the present and future scenarios of composite waste management in the UK. The impact was compared to conventional disposal routes and other prominent recycling technologies, such as cement kiln co-processing and mechanical recycling, by developing energy and material flow models for each waste treatment strategy. Variables, such as the type of waste, the quantity of recycling facilities in the UK, and waste haulage distance, were examined to inform the lowest impact deployment of recycling technologies. Cement kiln co-processing, mechanical, and fluidised bed recycling technologies reduced the global warming potential of processing wind blade waste compared with conventional disposal routes, with impacts of −0.25, −1.25, and −0.57 kg CO2e/kg GRP waste, respectively. Mechanical recycling had the lowest global warming potential resulting from low greenhouse gas emissions associated with the process itself and potentially high offsets by replacing glass fibre in the production of moulding compound. Composite wind turbine blade waste was found to be a particularly promising feedstock for the fluidised bed process due to relatively low resin content diminishing direct greenhouse gas emissions during thermal decomposition, as well as high material recovery offsets due to the high glass fibre content of this waste stream.

Investigation of mechanical behavior of glass fiber reinforced extruded polystyrene core material composites.

Layered composites are composite materials created by combining different layers of materials. Each layer can possess unique properties, often tailored to meet specific application or design requirements. These composites have found applications in various sectors due to their features, which include lightness, excellent impact properties, and customization according to specific application areas. In this study, glass fiber reinforced polymer foam core layered composite materials were produced. EPS polymer foam was used as the core material. During production, polymer foams and fibers were bonded to the upper and lower sides of the foams using resin. Samples were produced with 4 and 6 layers on both sides, totaling 8 and 12 layers, respectively. The vacuum bagging method was employed in production, utilizing the manual laying technique. Upon completion of production, the materials were cut into sizes conforming to standards and converted into samples. Subsequently, three-point bending and low-speed impact tests were conducted on the produced samples. As a result of the impact tests, perforation occurred in the 8-layer samples of 200 g m-2 glass fiber composites, while rebound was observed in the 12-layer samples. Although more deformation occurred in the 8-layer glass fiber composites of 300 g m-2 than in the 12-layer samples, both sets of experiments resulted in rebound. Similar results to the impact tests were obtained in three-point bending tests, with higher strengths observed in the 12-layer samples compared to the 8-layer samples. Composite samples with fiber layers of 300 g m-2 exhibited better performance than samples with 200 g m-2 fibers.

Regression model-based parametric analysis of drilling of multi-walled carbon nanotubes-added glass fiber composite laminates

Multi-walled carbon nanotubes (MCNTs)-enhanced glass fiber composite (GFC) laminates are among the most promising materials for fulfilling various structural and non-structural requirements. They have also shown exceptional functional applications as excellent electrical and thermal conductors, as well as electromagnetic interference shielding materials. The present work primarily focuses on developing regression models for the drilling process of 0.3 wt% MCNTs-GFC laminates. For experimentation, three different coated drills—carbide, TiCN-coated, and TiAlN-coated—are used under both dry and chilled air cutting environments. The lowest thrust force, torque, and delamination factor were observed at a feed rate of 10 mm min−1 and a speed of 1500 RPM using a TiCN-coated drill in a chilled air environment. Regression analysis reveals that feed rate significantly influences thrust force, as justified by the R2 value, which is above 90% for the selected cutting conditions. The corresponding t and F statistics values indicate the statistical significance of the relevant explanatory factors. The efficiency of the developed models is further validated by considering the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) values, which are 136.9 and 144.7, respectively. These values indicate a good regression fit and likelihood of the models for data prediction. Additionally, there is a strong correlation (coefficient > 0.85) between thrust force and delamination factor under the selected cutting environments. Concurrently, the developed regression models are simulated and evaluated for random experiments (Nos. 87, 125, 187, 243, 244, and 399), and the predicted responses closely match the experimental values.

The use of natural (coconut) and artificial (glass) fibers in cement – polymer composites: An experimental study

Fiber reinforced concrete composites are a group of high-performance materials with considerably enhanced stress-strain properties. Similar effects can also be achieved using polymeric binders whereby the inclusion of the polymers as binder can significantly enhance the physical-mechanical properties of the resulting concretes. In this regard, the following study investigates the impact of utilizing natural (e.g., coconut) versus artificially manufactured fibers (e.g., glass fiber) in polymer-cementitious composites. In doing so, 14 mixes were produced using various ratios of the two fibers. To evaluate the properties of the produced samples a series of tests including flow diameters, unit weights, water absorption values, compressive strengths, flexural strengths and ultrasound transmission rates were determined. Also, to evaluate the microstructural cohesion of polymer-cement and polymer-coconut samples, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) has also been used. The results show that the surface texture of fibers can play a key role in major engineering properties of the fiber reinforced concretes and that the natural fibers have great potential to be used as high-performance materials in cementitious composites. Also, it is found that the use of polymer as the main binder can provide higher adhesion with fibers containing smoother surface (e.g., glass fiber) at the interfacial transition zone (ITZ). In the end, recommendation for future studies is also included.

Eco-friendly 3D printed concrete with fine aggregate replacements: Fabrication, characterization and machine learning prediction

During the last decade, 3D printing technology has experienced significant development, especially for concrete printing in construction. However, eco-friendly 3D printed concrete with fine aggregate replacements has not yet been sufficiently studied. Herein, twenty-five (25) mix categories are designed for use in 3D printed concrete. The mix materials include fine aggregates, silica fume (SF), ground waste rubber tire (Ru), and glass fiber (GF) composites. The mechanical characterization (i.e., stress-strain relations) are investigated, and the mechanical performance (i.e., compressive and flexural strengths) are reported. Numerical simulations are carried out to validate the experimental results, and satisfactory agreements are obtained. Machine learning prediction model is developed using the experimental and numerical results to predict the compressive and flexural strengths of the aggregate-mixed 3D printed concrete. An inverse relationship was observed between the rubber content and compressive strength of 3D printed concrete (RuC) printing imperfections is highly correlated with high rubber content. Similarly, increasing fiber volume in fiber concrete (FC) resulted in a decreased compressive strength due to reduced interlayer bond. Notably, hybridized concrete (HC) exhibited comparable strengths to fiber concretes at 1% fiber content, but a significant strength increase was observed at 5%, 10%, and 15% rubber contents with 2.5% fiber volume. Better stress-strain response (i.e., higher strength) is observed with larger SF content. It is evident that the addition of SF, GF, and Ru to concrete, improves cost efficiency and the stress-strain behavior of 3D printed concrete. The reported eco-friendly 3D printed concrete has a relatively low peak strength compared to normal concrete but shows traces of fatigue resistance. The eco-friendly 3D printed concrete provides the alternative for normal concrete for in-situ construction applications.