Composites Part C Open Access最新文献

{"title":"Post-heating punching shear performance of seawater sea-sand concrete GFRP-reinforced two-way flat slabs","authors":"Sogand MohammadNezhad,&nbsp;Mahdi Nematzadeh","doi":"10.1016/j.jcomc.2026.100777","DOIUrl":"10.1016/j.jcomc.2026.100777","url":null,"abstract":"<div><div>The freshwater and natural sand depletion has promoted the utilization of seawater and sea–sand as a sustainable alternative in concrete production. Meanwhile, replacing conventional steel reinforcement with glass fiber–reinforced polymer (GFRP) bars represent an effective approach to enhancing the durability of reinforced concrete systems, particularly flat slabs. However, these systems remain susceptible to elevated temperatures and punching shear failure. This study investigates the behavior of seawater sea–sand concrete (SWSSC) flat slabs reinforced with GFRP bars under elevated temperatures, followed by punching shear loading. Key variables included slab thickness (60 and 80 mm), reinforcement ratio (0.57 and 0.85%), concrete compressive strength (35 and 60 MPa), and exposure temperature (20, 200, 400, and 550 °C). Performance metrics such as punching shear capacity, cracking load, stiffness, toughness, ductility, punching angle, and load–deflection response were evaluated and compared with existing code-based and analytical models. Results show that increasing the reinforcement ratio enhances load capacity, toughness, and crack control. Greater slab thickness significantly improves load capacity, stiffness, and energy absorption. Higher concrete strength increases cracking load and reduces the adverse effects of elevated temperatures. Temperature effects reveal that mechanical properties are largely preserved up to 200 °C, while notable degradation in strength, stiffness, and toughness occurs at 400 and 550 °C. Additionally, increases in reinforcement ratio, slab thickness, or concrete strength led to a reduction in the punching shear angle. Moreover, any parameter increase, reinforcement ratio, slab thickness, or concrete compressive strength, led to a reduction in the punching shear angle.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100777"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148634724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical modeling of effective through-thickness thermal conductivity in intumescent glass fiber-filled polypropylene for thermoplastic battery enclosures under various external fire exposures","authors":"Mehrnoush Farhadi,&nbsp;Amol Avhad,&nbsp;Han Goossens,&nbsp;Manjunath Parameswaran,&nbsp;Ratnesh Khandelwal,&nbsp;Brian Y. Lattimer,&nbsp;Scott W. Case","doi":"10.1016/j.jcomc.2026.100790","DOIUrl":"10.1016/j.jcomc.2026.100790","url":null,"abstract":"<div><div>This study examines the behavior of a glass-filled, intumescent, flame-retardant polypropylene (FR-PP). It extends previous investigations by incorporating the contributions of both solid and gaseous phases into the through-thickness thermal conductivity of intumescent composite systems across multiple spatial scales and under varying orientations of external fire exposure. Thermal computational models were developed and validated against experimental measurements.</div><div>Two different approaches are used for the thermal loads. Firstly, the pyrolysis behavior of the material, along with relevant test geometries and boundary conditions, was modeled using PyroSim, which utilizes the Fire Dynamics Simulator solver. The model captures the material’s multi-step degradation kinetics, including reactions in the condensed and gas phases and associated phase transitions. Material properties were experimentally characterized, and reaction parameters were extracted through multiple analytical techniques. Secondly, an inverse heat transfer approach was applied to a surrogate stainless-steel plate to estimate the transient spatial heat flux distribution, enabling the quantification of thermal loads across a broad spectrum of complex fire exposure scenarios without necessitating explicit consideration of combustion or pyrolysis, nor reliance on direct temperature measurements at the exposed, actively burning surface of specimens. The resulting heat fluxes were mapped onto an Abaqus finite element analysis model as transient, spatially varying thermal loads.</div><div>This study establishes lower and upper bounds for temperature prediction by applying series and parallel multiphase approaches, respectively, under each fire scenario. It also presents the interpretation of thermal conductivity, not merely as a temperature-dependent property, but also as a function of the rate of thermal exposure.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100790"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148729882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the potential of Gene Expression Programming for accurate and practical prediction of peak and ultimate compressive strengths in SMA spiral-confined concrete cylinders","authors":"Saeed Eilbeigi,&nbsp;Amir R. Masoodi","doi":"10.1016/j.jcomc.2026.100772","DOIUrl":"10.1016/j.jcomc.2026.100772","url":null,"abstract":"<div><div>In recent years, Shape Memory Alloys (SMAs), a class of smart materials, have gained attention for their potential in actively confining concrete elements. However, a review of existing literature indicates that limited research has been dedicated to predicting the mechanical response of concrete cylinders confined with SMA spirals. To enhance the accuracy and practical applicability of predictive models, especially for estimating peak and ultimate compressive stresses, the development of new empirical formulations is essential. Soft computing techniques have emerged as powerful tools for modeling complex systems in civil engineering, offering flexible and data-driven alternatives to traditional analytical methods. In this study, Gene Expression Programming (GEP) is employed to establish reliable predictive equations for the mechanical performance of SMA-confined concrete cylinders. A dataset comprising 42 experimental results from uniaxial compression tests on plain concrete specimens confined with SMA spirals was assembled. Using GeneXpro Tools software, the GEP algorithm was applied to derive optimal relationships. The results indicate that GEP delivers the highest predictive accuracy, achieving an R² of 0.9553, an RRMSE of 0.0678, and an PI of 0.0343 for peak strength equation. In the case of the ultimate strength equation, the obtained values were R²=0.8257, RRMSE = 0.1724, and PI = 0.0903, indicating satisfactory predictive capability. The accuracy and generalizability of the proposed models were subsequently evaluated against existing empirical formulations. The findings demonstrate that GEP provides a robust and effective approach for predicting the behavior of SMA-confined concrete and can yield equations that are both practical for engineering applications and accurate in predictive capacity.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100772"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electromechanical performance and durability of embedded CNT-doped filaments for strain sensing in composite laminates","authors":"E. Madia,&nbsp;G. Tzortzinis,&nbsp;S. Demski,&nbsp;M. Misiak,&nbsp;K. Dydek,&nbsp;P. Kozera,&nbsp;A. Kurnyta,&nbsp;P. Duralek,&nbsp;A. Boczkowska,&nbsp;A. Filippatos,&nbsp;M. Gude","doi":"10.1016/j.jcomc.2026.100766","DOIUrl":"10.1016/j.jcomc.2026.100766","url":null,"abstract":"<div><div>This study investigates the development and evaluation of CNT-doped thermoplastic filament sensors for in-situ monitoring of composite structures. The piezoresistive behavior of filaments is first characterized under tensile loading by varying CNT content and sensing length to identify a suitable sensor configuration. A configuration with 4 wt% CNT content and a sensing length of 200 mm was selected based on its stable and reproducible response. The selected sensor is then placed at different laminate locations and evaluated under static three-point bending, using conventional electrical resistance strain gauges as a benchmark. The influence of plasma surface treatment on mechanical and sensing performance is also examined, and sensor robustness is assessed through cyclic bending and accelerated weathering. Static tests show that sensor placement has a negligible effect on laminate flexural modulus, with differences below 1% between embedded and surface-mounted configurations. Plasma-treated specimens exhibit increased stiffness but reduced piezoresistive linearity. The sensors exhibit linear and repeatable responses with gauge factors of 0.3–0.4 in the low-strain regime (0–0.3%). Under cyclic loading (2000 cycles), the sensors stabilize after an initial conditioning phase and maintain repeatable responses. Weathering induces a baseline resistance shift (up to <span><math><mo>∼</mo></math></span>6%) without degrading sensing functionality after reconditioning. Overall, the results demonstrate that CNT-doped filaments are suitable as embedded strain sensors for structural health monitoring.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100766"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid continuum shell-solid modelling for effective digital twinning of composite scarf repairs","authors":"C. M. T. Tien,&nbsp;T. Shelley,&nbsp;K. Pattarakunnan,&nbsp;M. Hall,&nbsp;P. Crothers,&nbsp;X. Zeng,&nbsp;P. Schubel","doi":"10.1016/j.jcomc.2026.100757","DOIUrl":"10.1016/j.jcomc.2026.100757","url":null,"abstract":"<div><div>This study presents a focused review and implementation of FEA methodologies for modelling scarf repairs in carbon fibre–epoxy laminates within a digital‑twinning context. A hybrid continuum shell-solid FEA strategy is proposed, in which continuum shell elements are used to represent the composite laminates and solid elements are employed to capture the adhesive layer response. The proposed approach is validated against benchmark simulations, demonstrating high fidelity in stress distribution and damage prediction while achieving a substantial reduction in computational cost. The resulting solver provides a computationally efficient and accurate foundation for integration into broader digital‑twinning frameworks for composite repair assessment.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100757"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanism-governed crashworthiness of hybrid 6061-T6 aluminum-melaleuca leucadendra composite honeycomb structures with stress-based trigger design","authors":"Sintya Meira Pratiwi,&nbsp;Harus Laksana Guntur,&nbsp;Fahmi Mubarok,&nbsp;Riyki Apriandi,&nbsp;Moch Zulfikar Eka Prayoga,&nbsp;Imam Muzaki","doi":"10.1016/j.jcomc.2026.100769","DOIUrl":"10.1016/j.jcomc.2026.100769","url":null,"abstract":"<div><div>Hybrid composite structures integrating metallic shells with natural fiber reinforcements offer a promising route for developing lightweight and sustainable energy-absorbing systems. However, the roles of composite architecture and material systems in governing deformation mechanisms and load transfer remain unclear. This study investigates a hybrid crash box combining 6061-T6 aluminum with a natural fiber composite derived from galam bark (<em>Melaleuca leucadendra</em>) in a honeycomb configuration. Four structural configurations were considered: a base model, a horizontal honeycomb with stress-based triggers (CH1), a horizontal honeycomb without triggers (CH2), and a vertical honeycomb without triggers (CH3). Epoxy and polyester matrices were employed to evaluate the material effects. Numerical impact simulations were performed using ANSYS Explicit Dynamics to examine the interaction between composite architecture, material properties, and structural response. The results reveal that the composite architecture governs the deformation behavior by controlling the load transfer and deformation stability within the hybrid structure. The vertical honeycomb achieved the highest energy absorption (up to 5.97 kJ); however, it generated an excessive peak force owing to increased axial stiffness. In contrast, the horizontal configuration with stress-based triggers (CH1) promoted progressive folding and reduced peak force by 44.5% while maintaining stable energy absorption. The epoxy-based system exhibited improved load transfer and deformation stability, suggesting more efficient within the composite phase compared to the polyester system. These findings demonstrate that the interplay between composite architecture, matrix properties, and trigger design controls the balance between energy absorption and force mitigation, providing insights for the design of sustainable hybrid composite energy absorbers.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100769"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screen-printed polyetherimide smart inlays for surveillance of bonded joints in composite structures","authors":"Ann-Kathrin Klein,&nbsp;Riem Kilian,&nbsp;Chresten von der Heide,&nbsp;Julian Steinmetz,&nbsp;Christian Hühne,&nbsp;Oliver Völkerink,&nbsp;Andreas Dietzel","doi":"10.1016/j.jcomc.2026.100775","DOIUrl":"10.1016/j.jcomc.2026.100775","url":null,"abstract":"<div><div>Adhesive bonding is ideal for joining lightweight components made of composite materials. However, the reliability of these structural bonds, particularly in terms of fatigue crack growth, is a major concern. To mitigate this risk, structural health monitoring of the bonding is desired. This can be achieved by measuring strains at different locations in the adhesive bondline. Here, we present screen-printing on polyetherimide to realize a smart inlay that can be placed into the adhesive bondline during CFRP integration and can replace cleanroom-fabricated crack propagation sensors demonstrated earlier. The sensor layout is designed to enable crack monitoring by evaluating strain differences between two sensor rows. For the first time, smart inlays were fabricated and encapsulated entirely on polyetherimide, which has excellent adhesion strength to the epoxy matrix of CFRP. For strain detection, we used screen-printed carbon sensors. We selected screen-printing inks that could withstand the harsh conditions during CFRP fabrication. For the characterization of our smart inlay, we analyzed the screen-printed carbon sensors before and after integration into composites. After integration, the sensors were fully functional. As a striking result, after the entire fabrication and integration, the sensitivity of the screen-printed carbon sensors reached a gauge factor of up to 49.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100775"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D/4D printing of magnetically responsive PETG-PBAT-Fe3O4 nanocomposite: Comprehensive experimental investigation of mechanical, thermal, microstructural and shape memory properties","authors":"Saeed J.A. Ali,&nbsp;Davood Rahmatabadi,&nbsp;Mostafa Baghani,&nbsp;Majid Baniassadi","doi":"10.1016/j.jcomc.2026.100768","DOIUrl":"10.1016/j.jcomc.2026.100768","url":null,"abstract":"<div><div>4D printing of shape memory polymers (SMPs) has emerged as a powerful approach for fabricating structures capable of programmed, stimuli-responsive shape transformations. In this work, magnetically and thermally multifunctional PETG-PBAT-Fe₃O₄ nanocomposites were designed to achieve efficient dual-mode actuation while simultaneously improving mechanical performance and printability. PETG-PBAT (70/30) was selected as the base matrix and melt-mixed with Fe₃O₄ nanoparticles at 0, 10, 15, and 20 wt%, followed by fabrication using direct granule material extrusion. The composites were characterized by dynamic mechanical thermal analysis, uniaxial tensile testing, and scanning electron microscopy to evaluate viscoelastic properties, mechanical behavior, and interlayer morphology. Shape memory performance was assessed under hot-water activation and remote magnetic induction. The results show that Fe₃O₄ addition markedly enhanced stiffness and strength. The storage modulus increased from 1838 MPa for the neat blend to 2685 MPa at -100 °C for the 20 wt% composite, while the highest ultimate tensile stress was achieved at 10 wt% Fe₃O₄ (28.33 MPa, 45% higher than the unfilled blend). Uniform elongation decreased from 13.24% (neat) to 9.36% at 10 wt%. Shape recovery under thermal activation reached 97.4% within 8 s for the 10 wt% composite, and magnetic induction enabled 91.1% recovery within 120 s, outperforming higher loadings. Overall, an optimal Fe₃O₄ content of 10 wt% provides the best balance between mechanical robustness, print quality, and efficient dual-mode shape memory performance, highlighting its suitability for advanced 4D-printed smart structures.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100768"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upgrading algae Ulva spp. as silica substitute in rubber for tires: valorizing biomass for sustainable rubber composites","authors":"Félix Carrasco,&nbsp;Gaio Paradossi,&nbsp;Roberto J. Aguado,&nbsp;Quim Tarrés,&nbsp;Javier Cañavate,&nbsp;Marc Delgado-Aguilar,&nbsp;Xavier Colom","doi":"10.1016/j.jcomc.2026.100776","DOIUrl":"10.1016/j.jcomc.2026.100776","url":null,"abstract":"<div><div>The global proliferation of algae <em>Ulva spp</em>. presents a significant environmental challenge, but their biomass offers a valuable opportunity for sustainable material development. <em>Ulva spp</em>. can be used as a partial substitute for the silica present in the compositions of rubber for tires. This study presents the manufacturing and characterization details of various rubber for tire composites, where algae replace silica in compositions ranging from 5 to 40 phr. To prevent algae degradation at rubber processing temperatures, a prior study on thermal degradation has been conducted by thermogravimetry. To assess the effect of algae incorporation on rubber, the following features have been measured and intercorrelated: physical properties, thermal properties, loss of mass by abrasion, heat build-up, craze propagation, microstructure and morphology, and mechanical properties (tensile strength, elongation at break, tear resistance and modulus of elasticity). Two potential challenges should be considered: the lower temperature-related degradation of algae, compared to silica, and the potential formation of aggregates at algae proportions from 20 phr onwards, in detriment of the mechanical properties of the composite. Overall, this study demonstrates a viable circular economy approach, transforming a problematic waste stream into a functional, cost-effective, and energy-saving component for the tire industry.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100776"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fracture-fatigue damage prediction in CFRP laminates: A multi-scale thermo-mechanical approach","authors":"Lokesh Raj,&nbsp;Himanshu Pathak,&nbsp;Sunny Zafar,&nbsp;Amit Gupta","doi":"10.1016/j.jcomc.2026.100771","DOIUrl":"10.1016/j.jcomc.2026.100771","url":null,"abstract":"<div><div>Carbon epoxy composites offer low weight and excellent mechanical strength, however, under cyclic thermo-mechanical loads, their performance may degrade. This paper proposed a multi-scale computational approach to predict fracture-fatigue damage accumulation in carbon fibre reinforced polymer composites (CFRPC) laminated at elevated temperatures (below glass transition temperature of polymer matrix). Mori-Tanaka homogenization method is used to determine effective thermo-mechanical properties of laminates at mesoscale. These properties are employed in macroscale simulations incorporating different failure criteria (Tsai-Wu, Hoffman, and Rotem) for laminates with varying fibre percentages (45%, 53%, and 59%). The proposed model predicts tension-compression fatigue and correlates well with experimentally obtained fatigue life data. A custom script developed in COMSOL implements the failure models and damage accumulation to estimate fatigue life. By using scanning electron microscopy, post-failure analysis reveals typical damage mechanisms in laminates. This study provides a reliable multi-scale framework for predicting fatigue and damage evolution in composites under cyclic thermo-mechanical loading, providing valuable insights for aerospace applications.</div></div>","PeriodicalId":34525,"journal":{"name":"Composites Part C Open Access","volume":"20 ","pages":"Article 100771"},"PeriodicalIF":7.0,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148565447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}