In-situ 3D visualization of high-temperature damage of ceramifiable FRP composites under compressive loading using X-ray tomography and deep learning

Prediction of Immediate Deflection and Flexural Capacity of Unbonded Posttensioned Concrete Members Strengthened with External FRP Composites

A numerical framework based on CDM for complete fatigue life prediction of bi-directional FRP composites

Tubular T-joints are the most widely used structural connectors. FRP composites, with their superior intrinsic properties, can be a more suitable choice than steel. Computational fracture mechanics has been employed to develop finite element models for predicting adhesive and cohesive failures in bonded composite T-joints under combined loading, with clamped chord and brace. Three-dimensional stress analysis, in conjunction with appropriate failure criteria (Tsai-Wu for adhesive failure and parabolic yield for cohesive failure), revealed that the saddle point ( β = 0°) along the bottom toe line and middle fillet line of the bonded T-joint is particularly prone to adhesive and cohesive failures, respectively. Fracture growth analysis using VCCT demonstrated a predominant radial propagation of both adhesive and cohesive failures, primarily governed by opening mode. Simultaneous failure growth leads to mutual retardation, with cohesive failure significantly contributing to the suppression of adhesive failure propagation. Despite the interaction effects, fracture propagation within the bonded T-joint has intensified local stress concentrations, adversely impacting the structural integrity of the joint. Structural integrity of bonded T-joints to adhesive failure can be enhanced by using a circumferentially oriented ([0] 16 ) brace along with a cross-ply ([0/90] 4S ) chord for smaller cracks ( a a / f b ≤ 0.3), while circumferential ([0] 16 ) chord for larger cracks ( a a / f b ≤ 0.3). Circumferentially ([0] 16 ) oriented fiber reinforced brace and chord are proposed for improving the overall joint fracture resistance against simultaneous influence of adhesive and cohesive failures.

Static load-bearing capacity of multi-planar tubular DK-joints reinforced with FRP composites in offshore wind turbine foundations

Corrigendum to: Seismic rehabilitation of flexure-damaged RC shear walls using a hybrid UHPC–FRP composites with EBROG-installed strips and FRP anchors [Journal of Composite Part C: Open Access, Volume 18 (2025), Article 100665

Computationally efficient modelling of impact and perforation in woven FRP composites

Tailoring the fatigue response of flax FRP composites by exploiting Micro-structural re-arrangements and auxiliary loading sequences

ABSTRACT Glass fiber reinforced polymer (GFRP) composites are increasingly being used in various structural applications. But, due to their poor electrical conductivity, static charge generated during their use remained accumulated on the component surface and causes various undesirable static incidents like electrical shock to the people, fire, or explosion etc. These lead to significant loss of people and property. Anti‐static FRP composite can resolve this issue by dissipating the unwanted static charge. In this work we have utilized graphene and carbon nanotube (CNT) to enhance the electrical conductivity of normal GFRP and make it anti‐static. Matrix modification with 0.03 wt% CNT or 0.75% graphene was used for this purpose. At these loadings both surface resistivity (SR) and volume resistivity (VR) of GFRP come within 10 6 –10 7 Ohm range and the material becomes anti‐static. Flexural and dynamic mechanical properties of the anti‐static FRP composites also exhibited significant improvement. Hygrothermal aging was performed at two different temperatures (30°C and 60°C) to check the effect of temperature and humidity on anti‐static performance.

A novel temperature- and stress-dependent model for stiffness degradation and fatigue life prediction of FRP composites under cyclic bending

The research addresses the problem of strengthening damaged reinforced concrete structures of transportation facilities using modern composite materials based on carbon fiber (CFRP). Using the railway overpass of the Zaporizhzhia Ferroalloy Plant as an example, a detailed investigation of the stress-strain state of structural elements before and after damage occurrence was conducted using the finite element method in the ANSYS software environment. It was revealed that failure in the form of rupture of two lower rows of longitudinal reinforcement causes an increase in beam deflection by 32.9%, tensile stresses in concrete by 33.3%, and stresses in reinforcement by 32.7%. A strengthening methodology was developed through bonding unidirectional carbon fiber reinforced plastic with a thickness of 1 mm, elastic modulus of 121,000 MPa, and tensile strength of 2,231 MPa to the bottom flange of the beam. The obtained results of numerical modeling of the strengthened structure demonstrate high efficiency of the proposed approach: the deflection of the strengthened beam exceeds the parameters for the undamaged structure by only 13.0%, while stresses in the reinforcement increase by only 4.2%. Maximum stresses in the carbon fiber reinforced plastic do not reach 5% of its ultimate strength, indicating significant load-carrying capacity reserves of the strengthening system and justifying the use of composite materials for restoring the serviceability of damaged reinforced concrete elements. The conducted review of international experience in the use of FRP composites in the construction industry revealed advantages of strengthened structures compared to traditional restoration methods: efficient work execution, minimal dead load, high strength characteristics, resistance to corrosion and aggressive environments, preservation of element dimensions, and rapid restoration of operational characteristics. The research substantiates the feasibility of applying carbon fiber composite materials for reconstruction and strengthening of transportation infrastructure facilities in Ukraine under conditions of limited financial resources and the need to reduce construction work duration.

Abstract This study explores the fabrication and characterization of hybrid composite materials reinforced with two natural fibers, jute and coir, and a synthetic fiber, E-glass, with a focus on waste valorization. The aim is to ulitize short fiber waste generated from the use of these materials in various applications. Unsaturated polyester resin was employed as the matrix, and all composite samples were fabricated using the hand lay-up technique, followed by room temperature curing. The fabricated composite systems included, single-fiber composites: jute/polyester (J0), coir/polyester (C0), and glass/polyester (G0). Binary hybrid composites (50/50 wt.%), such as jute/glass (JG), jute/coir (JC), and coir/glass (CG). Ternary hybrid composites with varying jute/coir/glass ratios such as H1 (50/25/25 wt.%), H2 (25/50/25 wt.%), H3 (25/25/50 wt.%), and H4 (33/33/33 wt.%). Mechanical characterization revealed that the JG hybrids exhibited a 118% increase in impact strength (IS) compared to J0, while CG showed a 124% improvement over C0. The JC hybrid demonstrated enhancements of 75% in tensile strength (TS), 160% in tensile modulus (TM), and 38% in IS relative to C0. Although the ternary hybrids (H1—H4) showed lower mechanical performance than J0, they significantly outperformed C0, with H4 delivering the most balanced and optimal performance. Additionally, TGA (Thermogravimetric Analysis) was conducted to assess the thermal stability and degradation behavior of the composites, supporting their potential for sustainable applications through effective utilization of fiber waste.

Seismic rehabilitation of flexure-damaged RC shear walls using a hybrid UHPC–FRP composites with EBROG-installed strips and FRP anchors

Degradation mechanisms of FRP composites under coupled mechanical-chemical attacks: Synergistic insights from in-situ observation and molecular dynamics simulations

Data-driven prediction of failure loads in damaged FRP composites under four-point flexure

This study presents the development of a series of glass fiber reinforced thermoplastic polymer composites (GFRP) through the prepregs method using PC-COPE blends of varying compositions from 100/0 to 0/100 w/w and E-glass fabric. The blends of PC-COPE were made by a solution mixing method and composite laminates were made by a compression molding technique. Morphological analysis revealed partial compatibility of the blends and the key fracture mechanisms such as sheet/sheet delamination, matrix debonding, and shear banding clearly indicate an increase in ductility of PC due to the incorporation of COPE which has contributed to the observed tensile fracture behavior of these composites. The blend-based composites display higher impact strength (in terms of Izod impact and drop-weight impact) and tensile strength compared to the pristine PC composite. Drop-weight impact testing highlighted the transition from localized damage in pristine PC composites to a more global failure in PC-COPE-based composites, supporting their enhanced impact energy absorption capabilities. Interlaminar shear strength (ILSS) peaked at 20wt.% COPE, indicating optimal fiber – matrix bonding and enhanced resistance to shear failure. This improvement is associated with a slight reduction in tensile modulus, flexural strength and modulus. The abrasion resistance of the composites remains unaltered for the composites made with blends up-to 20wt.% of COPE and thereafter the values tend to decrease considerably with increasing COPE content in the matrix. Dynamic mechanical analysis (DMA) indicated a shift in the glass transition temperature and simultaneous broadening of the peak width in COPE-rich composites, correlating with increased flexibility and impact resilience. The study demonstrates that blending PC with COPE at optimized ratios provides a promising route to achieving high-performance FRP composites with improved impact resistance, toughness, and thermal properties, making them suitable for demanding engineering applications.

This study evaluates the mechanical performance of laminated composites with distinct weave architectures. Carbon, Glass and Carbon/glass intra-ply hybrid reinforcements were characterised. The selected weave pattern was plain, twill, hybrid, and unidirectional (UD). The novelty lies in selecting a particular weave architecture along with the reinforcement material for a targeted design. Mechanical characterisation included tensile, flexural, and short beam shear tests as per ASTM standards. Fibre volume fraction was measured using burn-off tests. All the test results were normalised with respect to the specimen thickness. The tensile strength of carbon/glass hybrid weave composites increased by 56 % and 45 % than twill carbon and plain carbon weave composites. Its flexural strength was 1.85 and 2.68 times than plain carbon and twill carbon weave composites. The flexural modulus of it was 1.31 and 2.35 times than plain carbon and twill carbon weave composites. Fractography analysis was carried out on the fractured specimens. In tensile and flexural specimens, failures included interfacial debonding, fibre pull-out, and fibre fracture. Hybrid carbon/glass laminates were found to improve flexural strength and modulus, with enhanced ductility due to the presence of glass fibres. This study is expected to provide a design guide for application-specific FRP laminate selection.

Fatigue life prediction of self-sensing hybrid FRP composites via electrical resistance monitoring and LSTM neural network

D-optimization of three-layer experimental set-ups for simultaneous estimation of transport thermal properties of FRP composites using contact and non-contact rear temperature measurements

Bond strength of lap spliced steel bars in RC beams strengthened with low-cost natural FRP composites: Experimental and theoretical study