Glass Fiber Reinforced Polymer Research Articles

Structural Behavior of Circular Concrete Columns Reinforced with Longitudinal GFRP Rebars under Axial Load

This paper presents experimental and theoretical assessments of the structural behavior of circular steel fiber-reinforced concrete (SFRC) columns reinforced with glass fiber-reinforced polymer (GFRP) bars subjected to a concentric axial compressive load. Laboratory experiments were planned to evaluate and compare the effect of different design parameters on the structural behavior of column specimens based on experiments and finite element (FE) analysis. The experimental variables were (i) concrete types, i.e., conventional concrete (CC) and fiber-reinforced concrete (FC), (ii) longitudinal reinforcement types, i.e., steel and GFRP bars, and (iii) transverse rebar configurations, i.e., tied and spiral with different pitches. Sixteen column specimens were fabricated and categorized into four groups with respect to rebar configurations and concrete types. The results showed that the failure modes and cracking patterns of those four column groups were comparable, particularly in the pre-peak branches of load-deflection curves. Even though the average ultimate load of the columns with longitudinal GFRP bars was 17.9% less than that with longitudinal steel bars, the ductility index (DI) was 10.2% greater than their counterpart on average. The addition of steel fibers (SF) to concrete increased the axial peak load by up to 3.1% and the DI by up to 6.6% compared to their counterpart CC columns without SFs. The DI of specimens was increased by higher volumetric ratios (up to 12%) and spiral types (up to 5.5%). The concrete damage plastic (CDP) model for FC columns was updated in the finite element software ABAQUS 6.14. Finally, a new simple equation was theoretically proposed to predict the axial capacity of specimens by considering the inclusion of longitudinal GFRP rebars, volumetric ratio, and steel spiral/hoop ties. Good agreement between the proposed model predictions and the experimental/numerical results was observed.

Experimental investigation on damage mechanism of GFRP laminates embedded with/without steel wire mesh under low-velocity-impact and post-impact tensile loading

Abstract To investigate the impact behavior and residual strength of glass fiber-reinforced polymer (GFRP) laminates embedded with/without steel wire mesh, low-velocity-impact (LVI) and post-impact tensile tests are conducted carefully. According to the wire diameter and spacing of steel wire mesh, we manufactured two groups of specimens via conventional vacuum-assisted resin infusion. Further, the digital image correlation technique was applied to record the strain evolution. Based on the results, including impact response history, failure morphology, strain contour, the failure mechanism and effect of the parameters of steel wire mesh is revealed in detail. The results show that the embedding of wire mesh can improve the impact resistance and residual strength, with a more significant effect as both the increase of wire diameter and decrease of wire spacing. Compared with GFRP laminates, the peak force of specimens with the thickest and densest wire mesh increase by 105% and 141% under LVI tests and 254% and 141% in post-impact tensile tests, respectively.

Comparative study of infrared nanosecond laser surface paint removal for carbon fiber reinforced polymer and glass fiber reinforced polymer

Carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) are widely used in aerospace applications due to their excellent properties. Green and efficient laser cleaning technology has a broad development prospect in the paint removal treatment of aerospace composites. However, the lack of theoretical analysis and guidance has prevented the industrial application of laser paint removal technology. An infrared nanosecond laser is used to clean the paint layer on the surface of CFRP and GFRP, and the best paint removal process parameters are explored. Surface micromorphology and 3D morphology of CFRP and GFRP after cleaning are observed to reveal the cleaning quality. The FTIR spectrum is used to verify the cleanliness of the paint layer. In addition, the contact angle and bonding force are tested, and the experimental results show that the surface wettability of both surfaces is enhanced after cleaning, and the paint adhesion of both surfaces is improved after repainting. Temperature monitoring, acoustic signal monitoring and high-speed photography monitoring are used to monitor the two cleaning processes respectively. The temperature, amplitude intensity, and plasma size of the two in the cleaning process are compared and analyzed. Based on the monitoring results, it is found that the cleaning mechanism of fiber-reinforced composites includes thermal ablation, vibration effect and plasma impact effect.

A carbon nanotube-based thermoelectric generator integrated into a smart composite for structural health monitoring

The next generation of advanced composite materials needs to simultaneously address issues such as energy harvesting and structural health monitoring (SHM). The objective of this study is to explore, for the first time, the possibility of utilizing a build-in thermoelectric generator (TEG) to fulfil self-sensing purposes. To this end, carbon nanotube-based (CNT) inks are employed to print TEGs onto a glass fiber substrate, which is then incorporated into a glass fiber reinforced polymer (GFRP) laminate. The output characteristics of the TEG-enabled specimens are measured, displaying an exceptional performance. The specimens are subjected to static, quasi static cyclic and dynamic loading. Adopting a novel idea, the conductive, fully integrated printed path is then exploited to serve as a strain/damage sensor. For this reason, its resistance is monitored online during mechanical loading. To corroborate the findings, acoustic emission (AE) is simultaneously applied. Results reveal that the self-sensing multifunctional composite can successfully monitor its structural integrity. In fact, it demonstrates high sensitivity with a gauge factor approximately equal to 3. Moreover, when the TEG operates as a piezoresistive sensor, it is characterized by reliability. We thus believe that the herein suggested approach unveils new prospects regarding the efficiency and the sustainability of composite structures.

Precast CSA-based concrete tunnel lining segments reinforced with GFRP bars: Challenges and opportunities

This research study investigates the potential of using Calcium Sulfoaluminate (CSA) binder as a sustainable alternative to ordinary Portland cement (OPC) in the production of precast concrete tunnel lining (PCTL) segments. The effectiveness of CSA-based concrete, reinforced with Glass Fiber-Reinforced Polymer (GFRP) bars, was examined through an experimental program. Comparative analyses, including analytical, experimental, and Life Cycle Assessment (LCA) comparisons, were conducted with OPC-based segments reinforced with traditional steel. The results indicate that the proposed CSA/GFRP solution has the potential to improve sustainability in mechanized tunnelling and prefabrication. A case study is also presented to support these findings.

Numerical Study of GFRP-reinforced Concrete Beams with Straight and Hooked-end Bar Lap Splices

Glass fibre-reinforced polymer (GFRP) has been increasingly used as the main reinforcement in concrete structures due to its durability and resistance to corrosion. However, there is a lack of data regarding the bond behaviour of GFRP bars with 180-degree hooked ends used in flexure concrete elements. To investigate the effects of the hooked ends of GFRP bars on the bond strength with concrete, beams reinforced with GFRP bars with straight and hooked-end lap splices at the midspan were modelled using ABAQUS/Standard software. The finite element models were validated using the experimental results of four full-size concrete beams. Two beam specimens had straight-end bars, while the other two had hooked-end bars. Sensitivity analysis was performed to find the proper values for model verification, such as dilation angle and mesh density. According to the outcomes of the parametric study conducted in this research, changing the length of the bar lap splices in the range of 15 to 40 times the bar diameter had a negligible effect on the beam’s overall behaviour. Increasing the number of reinforcing bars from 3 to 5 increased the beam flexural strength by about 33%, whereas increasing the diameter of the bars from 10 to 20 mm doubled the beam strength.

A Sustainable Solution with Improved Chemical Resilience Using Repurposed Glass Fibers for Sewage Rehabilitation Pipes

This paper introduces a sustainable sewage rehabilitation solution, utilizing repurposed glass fibers for enhanced chemical resilience and environmental conservation. The approach involves dividing a unitary pipe into segments, assembled during commissioning, aiming to reduce installation and transportation costs, particularly in less accessible areas. Each pipe segment comprises a multi-layered glass fiber composite sandwich, joined by an adhesive reinforced with recycled glass fibers. The glass fiber-reinforced plastic (GFRP) pipe features a core of blended sand impregnated with resin, an outer layer for impact resistance, and an inner layer to prevent corrosion. Chemical resilience is assessed through a 10,000 h strain corrosion study exposing both unitary and two-piece circular GFRP pipes to sulfuric acid in a deflected condition. An apparent hoop tensile test evaluates mechanical integrity before and after exposure. The experimental results reveal that the two-piece pipe with a tongue and groove joint (TGJ) with recycled glass fiber adhesive exhibits superior long-term bending stress and failure strain % compared to unitary pipes. This enhancement is attributed to the TGJ’s improved load-bearing capability and chemical resistance. The failure strain % of the two-piece pipe (1.697%) is higher compared to the unitary pipe (1.2613%). The long-term bending stress of the two-piece pipe obtained is 119.94 MPa whereas the unitary pipe reaches 93.48 MPa at the 50-year mark. The cost analysis supports the adoption of the two-piece pipe over unitary pipes due to a 40% reduction in carbon emissions and transportation cost. The novelty lies in the utilization of multi-piece pipes with enhanced chemical resilience, achieved through the incorporation of milled fiberglass reinforcements in the TGJ. Strain corrosion tests take a long time to perform; hence, an accelerated test is needed to improve the current recommended testing standard.

Experimental and numerical investigation of the usability of nonwoven hemp as a reinforcement material

This study presents experimental and numerical investigations on the use of chemically untreated and recyclable hemp fibers as reinforcement for outer wrapping in reinforced concrete beams. Hemp fibers, recognized as an alternative to Carbon Fiber Reinforced Polymer (CFRP) and Glass Fiber Reinforced Polymer (GFRP), were utilized in three forms: unwashed hemp, washed hemp, and hemp rope. The materials underwent distinct tensile tests, compression tests on cylinder specimens (15×30 cm), and 4-point bending tests on reinforced concrete beams (15×25×200 cm) wrapped with CFRP, GFRP, Glass Fiber Chopped Strand, Geotextile, and NFRP (Unwashed hemp, washed hemp, and hemp rope). Additionally, the epoxy used in wrapping underwent adhesive and tensile tests. Despite swelling during adhesion, untreated hemp demonstrated effectiveness in load-carrying capacity, positioning it as a viable alternative to costly petroleum-derived materials. A finite element model compared the experimental results, confirming the efficacy of untreated hemp fibers in reinforced concrete applications. This study contributes not only to the exploration of sustainable construction materials but also underscores the potential of untreated hemp fibers in meeting the demand for eco-conscious alternatives in structural reinforcement.

Bending energy absorption performance of composite fender piles with different winding angles

Abstract In recent years, there has been an increase in accidents involving vessels colliding with bridge piers. These ship–bridge collisions can result in tragic loss of life and severe damage to the bridge structure. To address this issue, a type of fender pile made of winding-formed glass fiber-reinforced polymer (GFRP) was proposed as a solution. In this article, three- and four-point bending tests were performed to compare and analyze the damage modes and load-carrying capacity of the fender piles at two different winding angles, namely 45° and 75°. Vertical impact test was simulated using ANSYS/LS-DYNA to verify finite element models. The results revealed variations in damage patterns and bending performance of GFRP piles under the two fiber winding angles. The simulation results suggest that GFRP fender piles can effectively increase the impact time of ship–bridge collisions and reduce the collision forces, thereby significantly improving the protection of bridge piers.

Comparative Analysis of the Size of Glass Fiber Woven Roving based on a Polyester Matrix on the Impact Strength of Composite Materials

<span lang="EN-GB">Laminated Glass Fiber Reinforced Polymer (GFRP) composites are widely used in various industries, such as boat building, car bodies, water tanks and pipelines, which in their use sometimes have the potential to be exposed to impact loads, especially in transportation equipment. Therefore, it is necessary to perform an impact test to determine the toughness value of a composite material against impact loads. This study aims to investigate the characteristics of fibreglass Woven Roving (WR)/polyester composites produced by the compression moulding process to determine the toughness of the composite material concerning changes in weave size. This research uses variations of glass fibre woven roving in sizes of 200 gsm, 400 gsm, 600 gsm. The impact test was conducted following the American Society for Testing Materials (ASTM) D6110-10. The impact test result showed that the lowest impact strength is found in a composite with a woven size of 200 gsm, which is 0.145 J/mm<sup>2</sup>, and the highest impact strength is found in composite with a woven size of 600 gsm, which is 0.280 J/mm<sup>2</sup>. </span>

Analysis on the ultraviolet curing process of resin‐based glass fiber composites based on finite element mesoscale model

AbstractThe resin curing process triggered by ultraviolet radiation possesses numerous advantages, including rapid speed, low cost, and minimal environmental impact. Due to the hindrance of light propagation by the medium, uneven curing or incomplete curing at the bottom may occur frequently, particularly when the material thickness is excessive. To address these issues and delve into the regularities of the light‐curing process, this study employed a modeling approach that separately represents fiber bundles and the resin matrix to construct a mesoscopic model of the resin‐based glass fiber‐reinforced composite material glass fiber reinforced polymer (GFRP). Based on the models of light propagation, light‐curing kinetics, and heat conduction, a multiphysics field decoupling model is established to simulate the light‐curing process of GFRP. Using this model, the temporal and spatial variations of the internal light field, degree of curing field, and temperature field within GFRP during the curing process are simulated. The mechanistic reasons for these variations are analyzed. Finally, in conjunction with the regular analysis based on the macroscopic model, the accuracy of the model and the obtained regularities are validated through experiments. This provides an effective analytical method for the study of light‐curing in resin‐based fiber‐reinforced composite materials.

Influence of multi‐walled carbon nanotubes on mechanical characteristics of glass fiber reinforced polymer composites: An experimental and analytical approach

AbstractAs a consequence of their magnificent performance like mechanical, electrical and chemical properties, multiwalled carbon nanotubes (MWCNTs) are widely used as a secondary reinforcement in composite field. It has been developed by arc discharging process under atmospheric pressure. Subsequently, MWCNTs doped nano‐composite were developed through hand lay‐up and followed by vacuum bagging techniques. Quasi – isotropic symmetrical laminate of eight layers (0/90)/(±45)/(±45)/(0/90)//(0/90)/(±45)/(±45)/(0/90) were fabricated under room temperature. To fabricate the composite laminates, purified MWCNTs were homogeneously dispersed in glass fiber reinforced epoxy with 0.5%, 1.25%, and 2 wt% loading. Tensile strength, tensile modulus, strain to failure and fracture behavior of unfilled and MWCNTs doped composite laminates were evaluated. Field emission scanning electron microscope (FE‐SEM) was employed to evaluate the structural and morphological characteristics of advanced nano‐composites. Reinforcement effect is found to be more pronounced in 1.25% MWCNTs embedded glass fiber reinforced polymer. This reinforcement effect was corroborated by tensile fractography which depicted by hackle region. Results indicated that tensile strength of 1.25 wt% nano‐composite increased by 47.36% with respect to 0.5 wt% MWCNT doped composites.Highlights Development of multi‐walled carbon nanotubes (MWCNTs) by arcing process. Fabrication of MWCNTs doped glass fiber reinforced polymer (GFRP) composites. Mechanical characterization of nano‐composites. Modeling of nano‐composites by Halpin‐Tsai equation. Fractrography of nano‐composites in details.

Multifunctional composite material based on piezoelectric nanofibers and Cu-CFRP electrodes for sensing applications

To monitor possible failures of a composite, several Structural Health Monitoring (SHM) systems have been developed. However, these methods typically involve embedding commercial sensors within the laminate, potentially compromising the material's strength.In this study, a self-sensing composite laminate was fabricated by interleaving poly(vinylidenefluoride-trifluoroethylene) (P(VDF-TrFE)) piezoelectric nanofibers between Glass Fiber Reinforced Plastic (GFRP) prepreg plies. Instead of conventional metallic sheets, hybrid Copper-Carbon Fiber Reinforced Plastic (Cu-CFRP) was used as electrodes to collect piezoelectric signals. This innovative approach offers two main advantages: enhanced interlaminar fracture toughness due to nanometric piezoelectric fibers and an intrinsic connection between copper wires and carbon, eliminating the need for additional electrical cables within the laminate. The effect of stacking sequence parameters on the self-sensing laminate's electromechanical response was investigated using a Design of Experiment (DoE) based on the Box-Benken method. Additionally, a lumped electric circuit model was employed to gain analytical insights into the piezoelectric behavior of the laminates.

Preliminary Study on Optimization Carbon Fibre Reinforced Polymer as Wrapping Structure at 90-degree Elbows Piping System via Finite Element Analysis

Carbon Fiber Reinforced Polymer (CFRP) considered as unique material as it is proven have the best mechanical properties which can be used as a wrapping. This composite material will be evaluated as a wrapping material using SolidWork version 2021 software. Elbow has been chosen as component to be wrapped as it is one of the most critical parts in a pipeline system. Thus, this research focuses on 90-degree butt welded elbows. The study evaluated different lamination and thickness of CFRP as a wrapping framework for elbows. Static analysis also was stimulated to analyze the stress and strain exerted on elbows at extrados location. Based on static analysis simulation from SolidWork software, lamination orientation of (0º) with 6 layers exhibit lowest stress for all the pressure tested ranging from 0.86MPa to 19.65MPa for 90-degree defected elbow at extrados location. Besides, comparing CFRP and Glass Fibre Reinforced Polymer (GFRP), CFRP showed it able to reduce stress compared to GFRP when tested on the same defected elbow. Lastly, the flow simulation in CFD showed there were no leakages especially on defected area and no sudden changes on pressure, velocity, and temperature.

Impact of process parameters in drilling of glass epoxy composite with clam shell and cenosphere filler: A comparative analysis

Drilling is one of the secondary machining techniques most frequently utilised when Glass Fibre Reinforced Polymer (GFRP) materials are assembled into a structure. The present work examines the drilling GFRPs and analyses hole quality based on the different traditional parameters: feed rate, spindle speed, and drill tool diameter. However, the hybridization of glass fiber- reinforced polymers (GRPs) by incorporating fillers as secondary reinforcement in the present piece of research has introduced new challenges for hole drilling and achieving the desired surface finishes. The delamination at the hole entrance and exit, considering the drill diameter of the HSS twist drill (6, 8, 10 mm), feed rate (0.04, 0.08, 0.12 mm/rev), cutting speed (1000, 1200, 1400 rpm), and filler content (0, 10, 20 wt.%) in GFRP, are the major factors are considered. The fillers used are clamshell powder and cenosphere, which are marine waste and thermal power plant waste, respectively. The present paper aims to study the effect of these fillers on the drilling-induced damages to the holes in terms of delamination factor, surface roughness, and dimensional accuracy of the hole (taper error, circularity error) of GFRPs. The most widely preferred Taguchi experimental design has been used for optimising the process parameters to obtain minimum delamination, surface roughness, and hole error. The study also aims to develop a correlation between feed rate, cutting velocity, drill diameter, and filler content with the delamination factor, surface roughness, taper error, and circularity error in a GFRP material. The observed results show that clamshells filled GFRP shows lower delamination, surface roughness, circularity error, and taper error compared to cenosphere filled GFRP composites under the same process parameters. It indicates the positive impact of the fillers in the drilling of GFRP, where the main objective is to reduce drilling-induced defects.

Enhancing performance of concrete with glass fiber-reinforced polymer short rebars as coarse aggregates by confinement

Cutting glass fiber-reinforced polymer (GFRP) waste into aggregate-size reinforcing bars (short rebars) as coarse aggregates in concrete shows to be an effective approach for recycling waste GFRP composites. The resulting concrete with such short rebars however exhibits a reduction in the compressive strength comparing to the corresponding normal concrete, making it unable to be directly used for structural elements. The concept of using the confining jacket is therefore employed for such concrete to improve its compressive strength and toughness and to be used in structural elements. A total of 48 cylindrical specimens were prepared and tested under axial compression with the replacement ratio of coarse aggregates by the GFRP short rebars and the stiffness of the confining jacket as the two test parameters. The test results indicate that incorporating short GFRP rebars results in a reduction in compressive performance by up to 57.2%, and the use of CFRP jacketing significantly enhances the performance of the concrete with or without GFRP short rebars. Such enhancement tends to be more significant when the stiffness of the confining jackets or the replacement ratio increases. The reduction in the compressive strength due to the incorporation of 25% recycled GFRP short rebars is from 57.2% to 30.7%, when the number of layers of the confining CFRP jacket increases from 0 to 3 piles. Comparisons were made between the test results and the predictions from two widely-used stress-strain models for confined concrete, showing that both models overestimate the ultimate axial strain and Teng et al.'s model generally produces the compressive strength slightly higher than the corresponding test results as well as the predictions from Jiang and Teng's model.

Experimental study on the fire resistance of all-composite and hybrid web-core sandwich panels for building floors

Fibre-reinforced polymer (FRP) composites and polymeric foams used in construction are susceptible to elevated temperatures, but little is known about the behaviour of composite sandwich panels under fire exposure. This paper presents an experimental study on the fire resistance of web-core composite sandwich panels with polyurethane foam infill for building floors. Two panel variants were considered: (i) an all-composite panel, with glass-FRP (GFRP) face sheets and webs; and (ii) a hybrid panel, with an additional fibre reinforced concrete (FRC) top layer. Five full-scale specimens were loaded in a four-point bending configuration, subjected to a constant service load, and subsequently exposed to a standard fire (ISO 834) on their bottom face. The effectiveness of passive fire protection systems, consisting of calcium silicate boards installed either adherent to the panels or forming an air cavity, was assessed. The following features were investigated: (i)temperature progression across the thickness of the panels, (ii)their mechanical response, (iii)failure modes, and (iv)fire resistance. The results obtained indicate that despite the vulnerability of composite sandwich panels to fire, relatively high fire resistances of 44 min and 49 min were obtained for the unprotected web-core all-composite and hybrid variants, respectively. The failure mechanism of the sandwich panels generally involved local compression and in-plane shear failure of the webs. The use of suitable passive fire protections provided significant fire resistance increases of at least 45 min (adherent) and 60 min (with air cavity), allowing to exceed the 90 min threshold.

Experimental investigation of flexural bond behavior of sand-coated GFRP rebar embedded in concrete

Steel rebars used in Reinforced Concrete (RC) elements may be subjected to corrosion due to aggressive environmental conditions. Rebar corrosion reduces the durability and the structural capacity of RC elements. On the other hand, since the steel rebars affect the magnetic fields, it is not preferred to be used in RC structures which is used to carry the equipment that propagate magnetic waves such as toll plazas on highways. For these reasons, the use of Fiber Reinforced Polymer (FRP) rebars is increasing, especially in RC infrastructure constructions. The objective of the present study is to investigate the bond behavior of Glass Fiber Reinforced Polymer (GFRP) rebar with a sand-coated outer surface in concrete using the arched beam test method. The concrete strength and the embedment length were chosen as variable parameters and 34 beam test specimens were tested in the laboratory. A comparative analysis of the crack patterns, the diagonal crack angles and the failure modes of the specimens is made. In addition, the experimentally determined bond-slip relationships were compared with different analytical models in the literature. Consequently, a bond-slip model, which takes into account CMR (Cosenza-Manfredi-Realfonzo) for the increasing part and mBPE (modified Bertero-Popov-Eligehausen) for the decreasing part, is proposed to be used in the numerical models of RC beams with sand-coated GFRP rebars. A prediction model for the bond strength is proposed, along with a recommendation for an upper bound value for the bond stress, which indirectly offers a minimum embedment length for a bond without slippage.

Prediction of multiple transverse cracks in a composite beam using hybrid RNN-mPSO technique

The presence of faults is common in engineering composite structures. Precise detection of faults prior to failure has been the focal point for researchers working in this domain. Detection of damage from the modal characteristics is an age-old promising technique besides the artificial intelligence techniques such as neural network (NN), Artificial neural network (ANN), recurrent neural network (RNN), and particle swarm optimization (PSO) methods. However, multiple detection techniques combined can give better results. In this regard, recurrent neural networks (RNN) and modified particle swarm optimization (mPSO) are combined to detect damages in a glass fiber reinforced polymer (GFRP) composite cantilever beam. The proposed hybrid model consists of two stages; indices of relative natural frequencies applied to locate crack parameters (position and severity) by recurrent neural network technique and optimization of the results (position and severity) by mPSO. The results illustrate this method can be implemented to predict multiple transverse cracks and their parameters in a composite beam, manifested in the change of natural frequencies where the error is limited to 0.97% only.

Behaviour of steel-reinforced recycled aggregate concrete-filled GFRP tubular short columns under eccentric axial compression

Since the mechanical properties of recycled aggregate concrete (RAC) are different from those of natural aggregate concrete (NAC), the mechanical behaviour of reinforced RAC members has attracted great interest. Meanwhile, fibre-reinforced plastics (FRP) have been applied to improve the load capacity of concrete members owing to their good durability. This study primarily focused on the performance of glass FRP (GFRP) confined steel-reinforced RAC short columns (FCSRAC) under eccentric compression. In this study, 29 FCSRAC were used to understand the effects of the recycled coarse aggregate (RCA) replacement rate, strength of RAC, eccentric distance, fibre orientation of the GFRP tube, strength of the GFRP, and longitudinal reinforcement ratio on the eccentric compression behaviour. The results show that the longitudinal steel bar ratio and hoop strength of the GFRP tube play a critical role in the load capacity of the FCSRAC, especially at large eccentric distances. With improved steel bars and GFRP tubes, RAC can be used in core concrete to replace NAC in a column. In addition, a prediction model of the load capacity of the FCSRAC was proposed based on Samaan's model and the static equilibrium principle, introducing the eccentric distance, fibre orientation of the GFRP tube, and RCA replacement rate. The predicted results agree with the experimental results.