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Investigation of long-term performance monitoring of cementitious mixes modified with healing agents and polymeric additives of self-healing polymer modified mortar (SHPMM)
(2026-03-01)
Kanwal, Humaira
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Wang, Ziping
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Hao, Wenfeng
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Javed, Kamran
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Asim, Muhammad
Concrete and mortar exhibit durability limitations in aggressive environments due to cracking, high permeability, and construction defects. Polymer-modified and self-healing cementitious materials have emerged as sustainable solutions; however, the synergistic use of polymer modifiers with chemical–biological healing agents remains underexplored. This study investigates self-healing polymer-modified mortar (SHPMM) incorporating styrene butadiene rubber (SBR) and ethylene vinyl acetate (EVA) as partial cement replacements at 0%,4%,8%,12% & 16%. A healing system consisting of 5% calcium lactate, 5% sodium silicate, 1% sodium carbonate. Also 1% effective microorganisms was added to all mixes. Workability, mechanical performance, durability, and microstructural characteristics were evaluated through slump, ultrasonic pulse velocity, strength tests, rapid chloride permeability, SEM, and EDX analyses. The results indicate that polymer addition significantly improves workability, strength, and durability. Slump values increased steadily with increasing polymer content. Optimum performance was observed at 4% and 8% polymer replacement, where permeability was markedly reduced. Compared to the control mix, compressive strength increased by 7–11%, split tensile strength by 12–17%, and flexural strength by 31–33%. RCPT values decreased substantially, with reductions of 32% and 45% for 4% and 8% SBR, and 22% and 58% for 4% and 8% EVA, respectively. Microstructural analysis confirmed improved matrix densification and crack-healing efficiency. EVA demonstrated superior performance compared to SBR, attributed to its powdered form and enhanced bonding characteristics. Overall, the combined application of polymer modifiers and healing agents effectively improves the mechanical performance, durability, and self-healing efficiency of cementitious composites, offering a viable solution for sustainable infrastructure in aggressive environments.
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Microstructure and Mechanical Properties Evolution of P235GH TC1 Steel Fire Tubes from a Fire-Tube Boiler with 14 Tons Capacity and 13 Bars Pressure
(2026-02-01)
Peeratatsuwan, Chaiyawat
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Ariyakul, Yossiri
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Sangsawang, Chatnugrob
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Sukprasertchai, S.
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Chowwanonthapunya, Thee
Comprehensive understanding of the microstructural degeneration and mechanical property degradation is of great importance to evaluate the reliability of used boiler tubes. This study describes the microstructural and mechanical evolution of P 235GH TC1 steel fire tubes which had been used in a fire-tube boiler for 3, 5, and 20 years. The investigation includes visual inspection, dimensional examination, chemical composition analysis, microstructural studies, scanning electron microscopy equipped with energy-dispersive x-ray spectroscopy (SEM-EDX), x-Ray diffraction (XRD), and tensile tests. Results reveal that prolonged exposure to the actual fire boiler environment induced the high temperature and oxidizing atmosphere. This atmosphere facilitated the diffusion and oxidation of carbon and manganese, leading to the depletion of both elements in the aged tubes. The carbon and manganese depletion and the influences of thermal exposure stimulated pearlite decomposition, resulting in the formation of a ferrite-dominated microstructure. The presence of ferrite-dominated microstructure and the deterioration of the solid solution effect due to the carbon and manganese depletion caused a reduction of mechanical performance and plastic deformation resistance of aged tube. The microstructural evolution and mechanical property evaluation indicate the significance of additional microstructural investigation techniques, such as replica examination. This useful method should be included in the routine inspection of the age fire tubes, particularly for those in the prolonged service stage. The addition of this method can improve the reliability of regular inspections, especially for aged fire-tube boilers.
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Data-driven framework for prediction of mechanical properties of waste glass aggregates concrete
(2025-12-01)
Onyelowe, Kennedy C.
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Hanandeh, Shadi
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Kamchoom, Viroon
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Ebid, Ahmed M.
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Imran, Hamza
This research presents a novel data-driven framework for predicting the mechanical properties of waste glass aggregate concrete using six advanced metaheuristic optimization algorithms: Bat Algorithm (Bat), Cuckoo Search Algorithm (Cuckoo), Elephant Herding Optimization (Elephant), Firefly Algorithm (Firefly), Rhinoceros Optimization Algorithm (Rhino), and Gray Wolf Optimizer (Wolf). The study evaluates these models based on their ability to predict compressive strength (Fc), tensile strength (Ft), density, and slump using key statistical performance indicators such as SSE, MAE, MSE, RMSE, accuracy, R<sup>2</sup>, and KGE. Sensitivity analysis was conducted using Hoffman and Gardener’s method as well as the SHAP technique to determine the most influential parameter in the prediction process. Results indicate that the Firefly and Wolf algorithms exhibited the highest prediction accuracy across all four properties, with Wolf emerging as the overall best-performing model due to its superior generalization ability, lower error rates, and high correlation with experimental results. Among the input parameters, the water-to-binder ratio was identified as the most influential factor affecting the mechanical properties of waste glass aggregate concrete, as demonstrated by both sensitivity analysis methods. This highlights the critical role of optimal water content in achieving desirable strength and workability in sustainable concrete mixtures. The study’s novelty lies in the comparative assessment of multiple optimization algorithms applied to waste-based concrete, an approach that has not been extensively explored in previous research. Additionally, the integration of SHAP analysis for feature importance ranking provides an interpretable machine learning approach to concrete mix design, which enhances decision-making for engineers and researchers. The practical implications of this research extend to sustainable machine learning-based concrete design, where AI-driven optimization can help reduce the reliance on conventional trial-and-error methods. By utilizing waste glass aggregates, the study supports circular economy initiatives in construction, reducing environmental impact while maintaining structural performance. The proposed models can be implemented in real-world scenarios to optimize mix designs for large-scale applications, leading to cost-effective and eco-friendly construction materials. This research advances the field of smart construction by demonstrating the effectiveness of machine learning in sustainable material engineering, paving the way for future AI-assisted innovations in the industry.
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Enhancing the properties of a hypereutectic Al-Fe alloy through recycled aluminum scrap and ultrasonic melt processing
(2025-10-01)
Tangsuksan, Tawatchai
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Pandee, Phromphong
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Diewwanit, Onnjira
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Limmaneevichitr, Chaowalit
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Tyurnina, Anastasia V.
This paper focuses on the effects of using recycled aluminum beverage cans and ultrasonic melt processing (USP) on the microstructure and properties of a hypereutectic Al-Fe alloy that has potential in structural and electric applications. The proportion of recycled aluminum scrap used as the starting material varied, and its influence on grain refinement, intermetallic phase formation, precipitation hardening, and mechanical performance was examined. Ultrasonic melt processing (USP) was applied to refine the microstructure and improve phase distribution. The experimental results showed that both the addition of recycled aluminum scrap and USP significantly increased the hardness and tensile strength of the alloys, with further improvements observed after optimal aging treatments, although ductility slightly decreased. Additionally, the presence of alloying elements from the recycled scrap, such as Mg, Mn, Si, and Cu, led to a reduction in electrical conductivity while improving the precipitation hardening response. This study highlights the potential of using recycled materials and advanced processing techniques to develop sustainable, high-performance aluminum alloys for various industrial applications.
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Synergistic effect of recycled E-waste fiber and polyvinyl alcohol on the properties of green concrete incorporating recycled concrete aggregate
(2025-10-01)
Chatveera, Burachat
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Ejaz, Ali
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Hanif, Muhammad Adnan
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Saingam, Panumas
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Hussain, Qudeer
The growing demand for sustainable construction highlights the need for innovative concrete solutions using waste materials. Although recycled concrete aggregate (RCA), polyvinyl alcohol (PVA), and recycled electronic waste fibers (E-waste fibers) have been studied individually, their combined effects remain underexplored. This study addresses this gap by investigating the synergistic effects of coarse RCA (CRCA) and E-waste fibers on the fresh, mechanical, durability, thermal, and economic properties of green concrete. Fly ash replaced 20 % of cement, and PVA was added at 1 % by cement weight. Results showed that increasing CRCA content reduced workability and strength due to porosity. However, incorporating 4.5 % E-waste fibers significantly improved mechanical performance by bridging microcracks. Higher fiber contents negatively affected durability and workability. Thermal conductivity decreased with more CRCA and fibers, enhancing insulation. Economic analysis confirmed that 4.5 % E-waste fiber offers cost-effective performance. This study supports the sustainable use of electronic and construction waste in concrete.
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Influence of recycled electronic waste fiber on the mechanical and durability characteristics of eco-friendly self-consolidating mortar incorporating recycled glass aggregate
(2025-07-01)
Saingam, Panumas
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Chatveera, Burachat
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Roopchalaem, Jutatip
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Hussain, Qudeer
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Ejaz, Ali
In the paper, the sustainable production of eco-friendly self-consolidating mortar (SCM) is explored with waste glass as a partial and complete substitution for fine aggregate owing to crucial environmental concerns. For that, the waste glass was replaced at 0 %, 25 %, 50 %, 75 %, and 100 %, while electronic waste fibers were added at 5, 10, and 15 % levels. Results showed that mini slump flow values varied between 233 mm and 263 mm, which confirmed the self-consolidating properties of the material even at 100 % replacement of fine aggregates and an addition of 15 % fiber. The increase in waste glass replacement reduced compressive strength; notably, a 30 % decrease was identified at the maximum substitution level of 100 %. Meanwhile, the mixtures incorporating 5 % fibers demonstrated the highest compressive strength at all maturation periods and replacement levels, even more markedly than the control mixture. The water absorption also increased significantly with increasing waste glass levels, up to 28.87 % at 100 % replacement, indicating increased porosity. Thermal conductivity decreased substantially, ranging from 1.97 W/mK for the control to 1.39 W/mK for 100 % replacement, which could be considered an improvement in insulation properties. These results show the possibility of using waste glass and electronic waste fibers to develop green SCM with enhanced thermal insulation and optimized mechanical properties.
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Aging-induced enhancement of corrosion resistance in Al-4Ni-1Mn alloys through Al3(Sc, Zr) precipitates
(2025-05-05)
Masthong, Anuchit
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Eskin, Dmitry
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Limmaneevichitr, Chaowalit
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Pandee, Phromphong
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Diewwanit, Onnjira
Al-Ni-Mn alloys are attractive for high-temperature, corrosive environment due to the formation of stable intermetallic compounds that can reduce corrosion susceptibility. This study showed that the additions of Mn, Sc, and Zr in Al-4 % Ni alloys significantly enhanced hardness and thermal stability through the simultaneous effect of transformation of the Al + Al<inf>3</inf>Ni to Al + Al<inf>9</inf>(Ni, Mn)<inf>2</inf> eutectic and precipitation of Al<inf>3</inf>(Sc, Zr). The thermal stability of an Al-4 % Ni-1 % Mn alloy was very good when exposed to 350 °C for 60 h. Additionally, the hardness substantially increased in an Al-4 % Ni-1 % Mn alloy with the addition of Sc and Zr, showing an approximate increase of 30 %. The highest hardness achieved was approximately 50 % higher with the optimal Sc and Zr content as compared to the Al-4Ni-1Mn alloy. Addition of 1 % Mn to an Al-4 % Ni alloy decreased the current density (I<inf>corr</inf>) and increased the corrosion potential (E<inf>corr</inf>), indicating better corrosion resistance. The effects of Sc and Zr additions on corrosion were also investigated, revealing that the increased Sc and Zr content led to more aggressive corrosion in the as-cast condition due to the eutectic coarsening and a high solid solution concentration of Sc and Zr that led to microstructural instability and electrochemical effects. However, after aging at 350 °C, the corrosion resistance significantly improved due to the Al<inf>3</inf>(Sc, Zr) precipitates that interrupted the corrosion path.
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Synergizing Portland Cement, high-volume fly ash and calcined calcium carbonate in producing self-compacting concrete: A comprehensive investigation of rheological, mechanical, and microstructural properties
(2024-12-01)
Saingam, Panumas
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Chatveera, Burachat
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Promsawat, Pongsakon
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Hussain, Qudeer
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Nawaz, Adnan
The manufacturing of Ordinary Portland Cement (OPC) is one of the primary contributors to atmospheric CO<inf>2</inf>. The use of high-volume OPC replacement materials in self-compacting concrete (SCC) has been the focus of several investigations owing to the increased demand for environmentally friendly building materials. This paper presents the experimental investigation of the properties of SCC, where 25–70 % OPC was replaced with fly ash and calcined calcium carbonate (BCC). Different experimental tests, such as workability, mechanical properties, durability, and microstructural characteristics, have been carried out. The test results of workability showed that all the mixes were conforming to satisfactory conditions of EFNARC for the T500 flow timings within the range from 2.50 to 4.55 seconds and slump flow values within the range from 650 to 800 mm. This mix, here called 20F5C, had optimum behaviour with its 91-day compressive strength of 73.8 MPa, a gain of 7.7 % over the control. Replacement ratio, microstructure, and mechanical properties were correlated. Even high-replacement mixes like 50F20C provided a 91-day compressive strength of 58.9 MPa. This clearly shows the prospect of a considerable reduction in cement consumption while maintaining structural integrity. These results indicate the possibility of reduced OPC consumption in concrete production, which again identifies low carbon emission and utilization of waste according to international sustainability goals. The findings have revealed that SCC made with high-volume replacements of OPC could be an economically viable and environmentally friendly solution for the construction industry worldwide.
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Comprehensive Characterization of Gelatin Films from Goat Skin Incorporating Konjac Glucomannan: Physical, Mechanical, and Molecular Properties
(2024-12-01)
Hasdar, Muhamad
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Nalinanon, Sitthipong
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Kittiphattanabawon, Phanat
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Sriket, Chodsana
This study aimed to comprehensively investigate and characterize the physical, mechanical, and molecular properties of gelatin films made from goat skin incorporated with konjac glucomannan. The study involved three treatment groups, labeled GG/KG1, GG/KG2, and GG/KG3, which included konjac glucomannan at concentrations of 0, 10, and 20% (w/w), respectively. Glycerol at 20% (w/w) was also included as a plasticizer. All samples underwent homogenization and ultrasonic treatment. The addition of konjac glucomannan to the gelatin-based film resulted in changes such as increased thickness (0.033-0.093 mm), opacity (0.9910-1.0433 mm-1), color L* (92.45-92.77), color difference (48.13-48.38), swelling (65.53-69.47%), and contact angle (86.92-127.85o). Conversely, a decrease was observed in water activity (0.521-0.463 Aw), moisture content (9.87-9.62%), tensile strength (0.0171-0.0118 N/mm2), elongation at break (5.91-4.52%), young’s modulus (0.0029-0.0026 N/mm²), WVTR (118.99-116.82 g/m². day), transparency (81.59-67.33%), and water resistance (34.47-30.53 %). Additionally, the peaks of amides A, B, I, II, and III exhibit both a shift and an increase in intensity, suggesting structural modifications and molecular interactions. The microstructure also indicated the presence of goat skin gelatin and konjac glucomannan cross-linked in the film formation. Therefore, the addition of konjac glucomannan modifies gelatin-based films, enhancing their suitability for food packaging.
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Effect of para-wood ash and calcium carbonate on the properties of eco-friendly self-compacting mortar reinforced with electronic waste fibers
(2024-10-15)
Makul, Natt
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Hussain, Qudeer
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Nawaz, Adnan
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Saingam, Panumas
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Sua-iam, Gritsada
This paper deals with reducing CO<inf>2</inf> emissions from cement production and finding alternative uses for electronic waste (E-waste) fibers in some innovative applications in self-compacting mortar (SCM). In the present research, an attempt has been made to establish the optimum incorporation of E-waste fiber into SCM by varying the fiber content from 5 % to 25 %, combined with para-wood ash and calcium carbonate as supplementary cementitious materials. In this laboratory study, the mix design had a constant water-to-powder ratio of 0.35 and a cement content of 550 kg/m³. Additionally, 20 % of the cement volume was replaced by 10 % para-wood ash and 10 % calcium carbonate. The results indicated a continuous increase of the mini-slump values from 255 mm for the control mix to 270 mm for the mix with the highest fiber content. Mini V-funnel flow times increased from 3.63 to 8.83 s as the fiber content increased. Lower fiber contents of 5 % improved compressive strength because they had a reinforcing role in the matrix of SCM besides the microcrack-bridging role. Higher contents of 10–25 % decreased the strength due to the clustering of fibers and resulting voids. SEM analysis at 28 days showed increased voids with higher percentages of E-waste fibers and para-wood ash alone. The results underline that optimizing fiber content is critical in balancing workability and mechanical properties, and 5 % e-waste fiber content can be considered optimal for enhancing the performance of SCM. This work also creates part of sustainable construction practice with the green solution required to reduce CO<inf>2</inf> emissions and work accumulation against E-waste.

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