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This research focuses on the survey and study of building architecture built in approximately 1932-1992, in Nakhon Nayok Province, Thailand with the three research objectives: (1) to study modern architecture buildings in Nakhon Nayok that reach the criteria of modern building value for conservation and lifelong learning, (2) to create a roster of modern buildings in Nakhon Nayok by studying the distinctive features of architecture and its historical, social, economic, educational, and other valuable significances; and (3) to create a valuable buildings database according to modern architecture criteria, to be uploaded to the micro-phishing system, and to publish modern architecture conservation database in digital and photographic files as the database of Nakhon Nayok. The main features of the buildings are consistent with the nature of modern architecture that shows the structure importance, and the use of technology of various materials which shows the advance construction technology in those days. The buildings are as simple as a box. They are useful, respond to the public, worth to society and culture, and contain of historical significance. From the survey and study in Nakhon Nayok, it was found that there were 43 buildings reaching the criteria of modern building value for conservation and were saved in the database in accordance with the micro-phishing model. The details of 43 modern buildings are presented in a digital file format and photo database of modern buildings in Nakhon Nayok to propagate the modern architecture conservation database as a lifelong learning resource for the benefit of interested people.

Vocational teachers in building and construction in upper secondary school deal with complex situations of an organisational, vocational, and social kind. Recent research has shown that the teacher is the single most important factor for students' learning in school. Teacher-student relationships and the teacher's repertoire of teaching practices can be more important for the student's learning than class size, the classroom environment, and the student's socio-economic background. Beyond passing the journeyman's test, we know little about the craft knowledge and working life experiences vocational teachers in the building and construction trades have acquired over many years in the construction industry, and thus, what knowledge and experiences they bring into the vocational teacher role. Learning in working life often takes place as an integrated part of work, and it is difficult to observe how learning happens. Craft knowledge is often tacit and personal. In this narrative, phenomenologically inspired study, learning is investigated as a bodily, internal process that simultaneously depends on the interaction with the material and social environment. Through narrative interviews with eleven vocational teachers in plumbing and carpentry, this study explores the teachers' backgrounds as vocational students and apprentices, and their extensive experience as craftsmen on different construction sites. The analysis shows that the building site drives craft-related actions and situations that generate a strong craft identity, professional working life experiences, and personal growth. Craftsmen at the construction site work under constant pressure in a social, physically, and mentally demanding work environment and consecutively solve problems. As professional craftsmen in the complex working environment, the teachers also acquired social and organisational expertise, which they intuitively transferred to their role as vocational teachers.

Purpose: The built environment is responsible for approximately 40% of the world's energy consumption, 30% of raw material use, 25% of solid waste, 25% of water use, 12% of land use and 33% of greenhouse gas emissions. Thus, environmental improvement and decarbonization are becoming increasingly critical objectives for the construction industry. Sustainable construction can be achieved through several practices, including: considering life-cycle assessment, circular construction, resource efficiency and waste management and providing eco-efficient materials, reducing energy demands and consumption and incorporating low-carbon technologies and renewable energy sources. To achieve sustainable construction goals, it is critical to educate the future workforce about decarbonization, circular construction and how to overcome the challenges involved in transitioning to sustainable construction. This study aims to understand the gap in student knowledge related to decarbonization and circular construction and the importance of incorporating these topics in civil engineering and construction management curricula. Design/methodology/approach: This study surveyed 120 undergraduate and graduate students at one of the largest minority-serving institutions in the USA to understand the gap in student knowledge related to decarbonization and circular construction as well as the importance of incorporating these topics in civil engineering and construction management curricula. The authors conducted several statistical measures to assess the consistency, reliability and adequacy of the sample size, including the Kaiser-Meyer-Olkin measure of sampling adequacy, the normality test to evaluate the appropriateness of using an ordered probit regression analysis and a multicollinearity test to observe the correlation between independent variables. The data was analyzed using ordered probit regression analysis to investigate the need for a curriculum that serves in educating students about decarbonization and circular construction. Findings: The results of this research highlight the gaps in students' knowledge pertaining to sustainable practices and the importance of providing future construction workforce with such knowledge to tackle global inevitable challenges. Originality/value: The findings of this study contribute to sustainable construction bodies of knowledge by advocating for a reformed curriculum to prepare the future workforce and adopt less carbonized, more circular approaches within the engineering and construction industry.

In this work, hydrogen diffusion behavior and mechanisms in the 4130X steel influenced by temperature, locally high concentration, and grain boundary were studied by leveraging both electrochemical hydrogen permeation experiments and molecular dynamics simulations. It was revealed that the hydrogen diffusion coefficient of the 4130X steel was increased with increasing temperature and decreasing locally high hydrogen concentration. The grain boundaries with misorientation below 15° characterized by an electron backscatter diffraction map were identified as hydrogen trapping sites, thus rendering a lower mean square displacement of hydrogen atoms and localized hydrogen diffusion trajectories. Furthermore, at a high hydrogen concentration of 4 at. %, these grain boundaries were saturated by hydrogen atoms, and platelet-like hydrogen clusters were formed within the lattice, which further inhibited the diffusive motion of hydrogen atoms. These findings would deepen our understanding of hydrogen embrittlement mechanisms by establishing the connections between macroscopic permeation behavior and atomic-scale hydrogen diffusion in structural materials. [ABSTRACT FROM AUTHOR]

The rapid advances in the additive manufacturing technology has led to the emergence of structural materials with arbitrary geometries that were previously challenging to produce using conventional machining techniques. Elastic constants are key mechanical parameters in structural material design; however, their accurate determination becomes challenging when dealing with materials possessing intricate geometries, which make traditional mechanical testing methods less practical. In this study, we accurately determined the elastic constants of a cuboid-shaped SUS304 specimen by combining resonant ultrasonic spectroscopy with the vibration-pattern-pairing method. The proposed method was then applied to a truss-shaped SUS304 specimen. To ensure the consistency of vibration modes, vibration patterns were matched by assessing the cosine similarity between contour plots, which depict the vibration patterns obtained from each of the three planes of the experimental specimen and those generated from a finite element model based on their color map. The measured elastic constants of the truss-shaped specimen were in reasonable agreement with those of the cuboid-shaped specimen and those obtained from tensile tests conducted on specimens obtained from an SUS304 block—the source material for the cuboid- and truss-shaped specimens. The optimization process for the elastic constants exhibited reproducibility, highlighting the efficacy of our approach for quantifying the elastic constants of materials with arbitrary geometries. The proposed method can assist material designers in accurately and efficiently determining the elastic constants of materials with intricate three-dimensional geometries and mechanical anisotropy. [ABSTRACT FROM AUTHOR]

The granular materials of soft particles (SPs) demonstrate unique viscoelasticity distinct from general colloidal and polymer systems. Exploiting dynamic light scattering measurements, together with molecular dynamics simulations, we study the diffusive dynamics of soft particle clusters (SPCs) with spherical and cylindrical brush topologies, respectively, in the melts of SPs. A topologically constrained relaxation theory is proposed by quantitatively correlating the relaxation time to the topologies of the SPCs, through the mean free space (Va) of tethered SPs in the cluster. The tethered SPs in SPCs are crowded by SPs of the melts to form the cage zones, and the cooperative diffusion of the tether SPs in the zones is required for the diffusive motion of SPCs. The cage zone serves as an entropic barrier for the diffusion of SP clusters, while its strength is determined by Va. Three characteristic modes can be confirmed: localized non-diffusive mode around critical Va, diffusive mode with Va deviating far from the critical value, and a sub-diffusive mode as an interlude between two limits. Our studies raise attention to the emergent physical properties of materials based on SPs via a topological design while opening new avenues for the design of soft structural materials. [ABSTRACT FROM AUTHOR]

The influence of microstructure on the response of energetic structural materials (ESMs) under shock conditions remains inadequately quantified, and the energy release process is not thoroughly understood. In this work, taking the classical Ni/Al ESM as an example, the shock response was investigated by the shock compression theory with the microstructure-based chemical reaction kinetics model. This theory mainly refers to the equation of the state of multi-component materials with mixture rule, and the reaction at the particle contact interface is built to form the multiscale thermodynamics model. The physical states of material after shock, including relative volume, temperature, and extent of reaction, were analyzed. The results revealed the effect of the burn velocity, particle size and molar ratio on the shock response. Furthermore, the model facilitates a comprehensive understanding of energy release, the extent of the intermetallic reaction, and the oxidation reaction. Despite the involvement of only a small portion of materials in the oxidation reaction, the energy release proportion was comparable to that of the intermetallic reaction. Additionally, insights into the effect of the microstructure on the energy release revealed by the model matched the tests well. [ABSTRACT FROM AUTHOR]

This study aims to improve the learning environment of a university viewing room by rehabilitating and refurbishing its ceiling, highlighting the critical role of infrastructure in education. The project is driven by the recognition that a well-maintained ceiling is essential for students' physiological well-being, eyesight health, safety, and comfort. Research indicates that poor air circulation in congested spaces with low ceilings can exacerbate the spread of airborne diseases, while inadequate ceiling illumination can harm visual health. Furthermore, exposed electric wires and an aesthetically unpleasing environment can distract students, negatively impacting their focus and learning outcomes. Upon approval, the project will proceed with planning, designing, and estimating, followed by the procurement of construction materials based on competitive bidding. All supplies will undergo thorough quality inspections. By addressing the structural inadequacies of the viewing room ceiling, this study aims to foster a safer and more conducive learning atmosphere, ultimately enhancing literacy outcomes and nurturing students' overall well-being. The findings of this project will underscore the significant impact of proper infrastructure on educational experiences, offering insights to the administration on the importance of maintaining high standards in school facilities. [ABSTRACT FROM AUTHOR]

The conversion of waste into value‐added products is critical to long‐term sustainability as waste disposal costs, landfilling space, and climate change would be reduced. Research and production industries investigate the possible use of natural fibers as a substitute for fossil fuels. Natural fiber‐reinforced polymer composites' physical and mechanical properties can be altered by natural fiber treatment, and the treatment choice relies on the desired properties and performance. In addition to cost‐profitability, environmental effects, and required performance, composites can be designed based on the product conditions. Disadvantages such as incompatibility of the hydrophilic natural fiber reinforcements with the hydrophobic polymer matrix often result in the tendency of the composite to have high moisture absorption, poor thermal stability, crystallinity, and mechanical strength. These factors critically impair the performance of the natural fibers as reinforcements in polymer composites, hence resulting in less‐favourable mechanical and physical properties. Physical, chemical, and biological treatments were examined to determine their effect on the durability and thermal, physical, and mechanical properties. It was observed that plasma treatment for bamboo fibers resulted in interfibral spaces and anchoring mechanisms between the resin and fibers, leading to increased load transfer. Chemical treatment at various concentrations improved the surface smoothness. The best mechanical, physical, thermal, and chemical properties for application as reinforcement in polymer composites were obtained at 6% for alkali treatments. Enzymatic treatment showed a significant impact on the impact and flexural strength of the composites. Factors such as duration, concentration, and extent of treatment need to be established for effective treatment, as prolonged treatments may damage the NFs' properties. This review comprehensively highlights the potential utilization of current natural fiber treatment methods for the potential of natural fibers as value‐added products for construction materials, considering their economical affordability, production of lightweight materials, sustainability, utilization of readily available waste material, and nature preservation. Furthermore, the three natural fiber treatment approaches for improving fiber‐matrix adhesion are discussed. The physical and mechanical properties of composites are highlighted, which aids in evaluating suitability for construction materials. [ABSTRACT FROM AUTHOR]

ABSTRACT Dissimilar metal welds are utilized in the energy industry to connect two materials with different material characteristics. In the case of nuclear power plants, the connected materials tend to be low‐alloyed steel and high‐alloyed material. Despite different material and corrosion properties, under the proper environmental conditions, the used construction materials and weld metals are protected either by a passive layer or by a high‐temperature oxide. Although dissimilar metal welds are used in both primary and secondary circuits, the most frequently documented damage is in the secondary circuit, where, in addition to material heterogeneities, local environmental heterogeneities may form. For dissimilar metal welds in WWER nuclear power plants, a water–water energetic reactor, a subtype of pressure water reactor, we note two main types of attack near the dissimilar fusion boundary: on the carbon steel side or on the high‐alloyed weld metal side (X10CrNiMoN16‐25‐6). The possible causes of the latter “atypical” corrosion attack are debated and can be generalized as a consequence of change of the grain boundary condition. [ABSTRACT FROM AUTHOR]

This study focuses on improving the mechanical properties and microstructure of cement-based materials, which are crucial for the durability and safety of construction projects. Conventional cement, although commonly used, has certain limitations in terms of its mechanical strength and durability. Therefore, there is a requirement for innovative methods to enhance these properties. This study investigates the potential of nano-TiO2 (titanium dioxide) as an additive to overcome these limitations. The objective of this research is to perform a thorough experimental analysis to examine how different concentrations of nano-TiO2 impact the mechanical performance and microstructural changes in cement paste and mortar. The study examines the influence of nano-TiO2 on the compressive and flexural strengths of cementitious materials. It also explores how nano-TiO2 modifies the microstructure to enhance compactness and resilience. The results suggest that incorporating nano-TiO2 into cement leads to a substantial improvement in both compressive and flexural strengths. This enhancement is particularly notable when the nano-TiO2 concentration is at an optimal level of 1.0% by weight. The SEM and XRD analyses demonstrate that this concentration enhances the microstructure by decreasing voids and facilitating the development of C-S-H crystals. However, excessive concentration may have negative consequences, such as the creation of extra empty spaces. The results indicate that nano-TiO2 has considerable promise in enhancing cement-based materials, thereby aiding the advancement of construction materials that are more long-lasting and effective. This study contributes to the knowledge of how nano-TiO2 improves cement and emphasizes its potential uses in the construction sector. [ABSTRACT FROM AUTHOR]

Recently an extensive growth in the market for Unmanned Aerial Vehicles (UAVs, drones) has been observed. Because of numerous advantages, their application in various areas is wide, starting with military, through civilian -- specialized up to amateur. The world market for civilian commercial drones in the year 2022 has achieved a value of more than USD 30 billion, and it is estimated that by 2032 it will have achieved USD 125 billion. Great expectations of reduction of world CO2 emissions and development of clean economy are linked with drones application in transportation and agriculture. Unfortunately, despite of the UAV -- related advantages mentioned above, the problem of their comprehensive recycling seems to remain unseen. Actions aimed at recycling lithium-ion batteries used in drones have been taken, whereas the challenge of recycling the construction materials applied in UAVs seems to be ignored, which, taking into consideration the estimated growth of the UAV market and a relatively short product lifecycle, may constitute a significant ecological problem in the near future. The aim of this article is to draw attention of scientific community to the crucial but unnoticed problem, which UAV recycling will become in the near future. The authors tried to assess the extent of drones recycling problem by review of UAVs market, emphasizing the most common construction materials applied in their production, and to outline the issues related to their recycling. Proposals of solutions facilitating introduction of circular economy into UAVs market have also been put forward. [ABSTRACT FROM AUTHOR]

The development of new composite and structural materials in various areas of industry has led to an ever-growing interest in research results regarding the applications of these materials. Combining these materials allows for the modification of the strength characteristics of structures and components manufactured from them. The article presents the results of bending test of carbon fibre reinforced polymers (CFRP) strips bonded with a two-component epoxy adhesive. Additionally, the reinforcement effect resulting from gluing composite strips (multilayer reinforcement) was compared with shortened strips. The positive and negative influences of shortening strips unidirectionally reinforced with long fibre have been discussed. Differences in the stiffness of the tested belt systems indicate that adding another belt increases the load capacity by approximately 100% of the bending force compared to the previous test of fixed-length belts. TSP tapes also show an increase in the ability to transfer the bending force by gluing subsequent strips, but not necessarily along the entire length, as shown in tests. Simulation tests showed smaller displacement compared to physical samples. The smallest differences between measurements and simulation results were recorded for two-layer configurations, while the largest differences were observed for four-layer strips. [ABSTRACT FROM AUTHOR]

Hybrid kenaf/glass fiber reinforced polymer composites have emerged as promising structural materials, garnering significant attention due to their unique blend of natural kenaf fibers and synthetic glass fibers. However, despite their potential, there remains a gap in the comprehensive understanding of their quasi‐static mechanical behavior, creep resistance, and fatigue performance. This paper addresses this gap by presenting recent advancements in studying these key properties of hybrid composites. Studies reveal that the combination of kenaf and glass fibers results in enhanced tensile, flexural, and impact strengths compared to individual fiber composites. Additionally, the hybridization offers improved creep resistance, with the glass fibers reinforcing the polymer matrix against deformation under sustained loads. Furthermore, investigations into fatigue properties demonstrate the resilience of hybrid composites to cyclic loading, contributing to prolonged service life in high‐stress environments. By elucidating the interplay between kenaf and glass fibers, this review underscores the potential of hybrid composites in various structural applications. The synergistic effects between natural and synthetic fibers offer a balance between sustainability, performance, and durability, making hybrid kenaf/glass fiber reinforced polymer composites a compelling choice for industries seeking lightweight, high‐performance materials in which aligns with the sustainable development goals (SDGs) especially on Goal 12. Highlights: In composite engineering, combining glass and kenaf fibers could cut production costs, yield high‐performance materials, and promote green technology.Substituting part of the glass fiber with kenaf can enhance the strength‐to‐weight ratio and promote greater biodegradability in current synthetic composites.Quasi‐mechanical properties of hybrid kenaf/glass‐based composites was enhanced by optimal stacking sequences, filler addition, and fiber treatment.Failures due to fatigue and creep can be reduced by hybridizing kenaf/glass fiber composites can prevent in polymer composite due to enhance elastic modulus.Enhanced tribological performance of hybrid kenaf/glass‐based composites due to less damage in microstructure via good interlocking of kenaf and glass in matrix. [ABSTRACT FROM AUTHOR]

AbstractAs the global population has continued to grow, the costs and environmental issues associated with traditional construction materials like cement and river sand have become increasingly problematic. This study explores the innovative enhancement of early-age mechanical properties of 3D-printable mortar through the incorporation of Styrene-Butadiene Rubber (SBR) latex and kaolin. Various sands (Lawrencepur, Chenab, and Ravi) were tested at 120 min for compressive stress, direct shear strength, Young’s Modulus, and Shear Modulus. Lawrencepur Sand exhibited the highest compressive stress (206.75 kPa) and shear strength (74.60 kPa), followed by Chenab Sand and Ravi Sand. Young’s Modulus values were highest in Lawrencepur Sand (7.93 MPa), indicating superior stiffness, while Shear Modulus was highest in Chenab Sand (3.79 MPa). Ravi Sand, despite lower mechanical strengths, was found optimal for printable mortar due to its fine particle size and desirable texture. The incorporation of SBR latex and kaolin resulted in reduced maximum deflection and enhanced load-bearing capacity over time, with Lawrencepur Sand containing 99.64% sand particles and minimal silt bearing the ultimate load effectively. This study highlights the potential of SBR latex and kaolin in improving the early-age mechanical properties and suitability of sands for 3D-printable mortar, providing a balance between mechanical performance and printability. [ABSTRACT FROM AUTHOR]

AbstractThe insulation and noise and vibration damping characteristics of complex systems used by humans, such as automobiles, airplanes and ships are becoming increasingly important from the early design stages to ensure an adequate level of comfort. Especially in the naval fields, the design of insulation plans is crucial to prevent the propagation of noise and vibrations on board of megayachts. Since it is quite complex to identify and correctly model the sources due to their deterministic and random nature, during the early design stage, the focus is on insulation rather than reducing the acoustic levels of the sources themselves. In this article, a method for analyzing sea trials on a superyacht will be proposed with the aim of analyzing how much the insulation materials can limit the levels of vibrational energy on board during the path between sources and receivers. A new a descriptor based on harmonic transmission energy through the structure is proposed for path insertion loss experimental identification. In particular, by using spectral analyses and synchronous averaging of sound levels in various areas of the superyacht, it will be possible to study the vibroacoustic insulation of structural materials and their damping coefficient. [ABSTRACT FROM AUTHOR]

Graphite/geopolymer composite is a promising smart material that can be used in various applications. This paper reports the design of strong self‐heating graphite/geopolymer composites with high graphite percentages up to 120 wt% of metakaolin. The physical, mechanical, electrical, and electrothermal performance of composites were investigated; the compressive strength was tested at various ages and the electrothermal performance was tested using AC and DC voltages. The results showed that a compromise between high compressive strength and high electrothermal conversion can be achieved when a specific balance between the percentage of the graphite and the water content is established. The current study specified the reason for the deterioration of the electrothermal performance of the graphite/geopolymer composites, that is, the formation of a barrier layer between the electrode and the sample surface; it has been found that this can be avoided by removing the free ions from the geopolymer via washing. A composite with 47 ± 1 MPa compressive strength and stable electrothermal performance of 98°C at 6 DC volts can be prepared using 90 wt% graphite and 57 mL water content. This work is a step in the future innovation of smart construction using self‐heating and antifreezing construction materials. [ABSTRACT FROM AUTHOR]

This study investigates the shear bond strength between four widely used façade stones—travertine, granite, marble, and crystalline marble—and concrete substrates, with a particular focus on the role of polypropylene fibers in adhesive mortars. The research evaluates the effects of curing duration, fiber dosage, and mechanical anchorage on bond strength. Results demonstrate that Z-type anchorage provided the highest bond strength, followed by butterfly-type and wire tie systems. Extended curing had a significant impact on bond strength for specimens without anchorage, particularly for travertine. The incorporation of polypropylene fibers at 0.2% volume in adhesive mortar yielded the strongest bond, although lower and higher dosages also positively impacted the bonding. Furthermore, the study introduces a novel fuzzy logic model using the Dombi family of t-norms, which outperformed linear regression in predicting bond strength, achieving an R2 of up to 0.9584. This research emphasizes the importance of optimizing fiber dosage in adhesive mortars. It proposes an advanced predictive model that could enhance the design and safety of stone-clad façades, offering valuable insights for future applications in construction materials. [ABSTRACT FROM AUTHOR]

The last decade was dominated by a serious problem that now affects all the planet's natural ecosystems: the increasing growth of plastics and microplastics that are difficult to dispose of. One strategy to mitigate this problem is to close the life cycle of one of them—polyethylene terephthalate (PET)—by reusing it within the most common building materials, such as mortars and concretes. The reuse of PET waste as aggregates also allows us to limit the CO2 emissions released during the production of natural aggregates. This paper analyzes the outcomes of many studies carried out on the characteristics of cementitious mixtures reinforced with waste PET material. Many researchers have demonstrated how PET used as reinforcement of mortars and concretes can produce an increase in the mechanical strengths of the corresponding cementitious mixtures without PET. The tensile strength of this resin is higher than that of concrete; so, by combining the two materials it is possible to obtain a mixture with an overall higher tensile strength, resulting in increased flexural strength and reduced cracking. Using an effective size of PET fibers, it is possible to achieve an increase in the ductility and toughness of the cementitious mixture. Several studies reveal that PET reinforcement reduces the density with a consequent decrease in weight and structural loads, while the workability increases using spherical and smoother PET aggregates. [ABSTRACT FROM AUTHOR]

Geothermal energy generation faces challenges in efficiency, partly due to restrictions on reinjection temperatures caused by scaling issues. Therefore, developing strategies to prevent scaling is critical. This study aims to simulate the scaling tendencies and corrosion effects of geothermal fluids on various construction materials used in scaling reactor/retention tank systems. A range of materials, including carbon steel, austenitic stainless steel, duplex stainless steel, two proprietary two-part epoxy coatings, and thermally sprayed aluminium (TSA), were tested in a simulated geothermal brine. Experiments were conducted in a laboratory vessel designed to replicate the wall shear stress conditions expected in a scaling reactor. The tests revealed varying scaling tendencies among the materials, with minimal corrosion observed. The dominant scale formed was calcium carbonate, consistent with geochemical modelling. The findings suggest that despite the high operating temperatures, the risk of corrosion remains low due to the brine's low chloride content, while the wettability of materials after immersion may serve as a useful indicator for selecting those that promote scaling. [ABSTRACT FROM AUTHOR]

Recycling and reusing industrial waste and by-products are topics of great importance across all industries, but they hold particular significance in the metal industry. Aluminum, the most widely used non-ferrous metal globally, generates considerable waste during production, including dross, salt slag, spent carbon cathode and bauxite residue. Extensive research has been conducted to recycle and re-extract the remaining aluminum from these wastes. Given their varied environmental impacts, recycling these materials to maximize residue utilization is crucial. The components of dross, salt slag, and bauxite residue include aluminum and various oxides. Through recycling, alumina can be extracted using processes such as pyrometallurgy and hydrometallurgy, which involve leaching, iron oxide separation, and the production of alumina salt. Initially, the paper will provide a brief introduction to the generation of aluminum residues—namely, dross, salt slag, and bauxite residue—including their environmental impacts, followed by an exploration of their potential applications in sectors such as environmental management, energy, and construction materials. [ABSTRACT FROM AUTHOR]

This study introduces an innovative algorithm that leverages terrestrial laser scanning (TLS) and the fuzzy analytic hierarchy process (FAHP) for the optimization of building repair methodologies. Focusing on multi-criteria decision-making (MCDM), itshowcases a methodology for evaluating and selecting the most effective repair strategy for building elements, balancing various conflicting criteria. The research applies TLS for rapid and accurate geometric data acquisition of engineering structures, demonstrating its utility in structural diagnostics and technical condition assessment. A case study on a single-family residential building, experiencing floor deformation in a principal ground-floor room, illustrates the practical application. Maximum deflection and floor deflection distribution were measured using TLS. Utilizing FAHP for analysis, the decision model identifies the most advantageous repair method from a building user’s perspective. This approach not only provides a systematic framework for selecting optimal repair solutions but also highlights the potential of integrating advanced scanning technologies and decision-support methods in the field of building materials and structural engineering. [ABSTRACT FROM AUTHOR]

The paper gives a directive toward assessment of resilience of building designed to comply the nearly zero energy standard in the current conditions and also points out the gap in the existing approach for evaluating the effect that the climate changes could have on building material behavior and systems degradation. A method is introduced for evaluating how the variation of energy need and in-situ production can modify the energy balance under the representative concentration pathway of the intermediate (RCP 4.5) and the worst emissions scenario (RCP 8.5). The results for a case study indicate that under RCP 4.5 scenario, the polyethylene foam insulation has the higher increment of heating demand (+ 9.8%) instead the cooling demand decreases by −4.2% (RCP 8.5) and −4.6% (RCP 4.5). The innovative materials are less affected (<1%) by temperature variations. On the other hand, the PV system degradation causes the reduction of in-situ production from −6.9% (RCP 8.5) and −8.0% (RCP 4.5). However, the analysis of the hourly balance suggests that the building resilience would be not compromised. Indeed, by evaluating the ratio between the self-consumption and the total request, it increases compared to the current conditions of around 2%. [ABSTRACT FROM AUTHOR]

In the frame of the Venezia2021 project the private 'Byzantine house' designed by Giuseppe Torres in 1905 was chosen as the emblematic architectural site which marks Venice's transition towards modernity, requiring study of its conservation in the lagoon environment of the city of Venice. In conjunction with the definition of a specific Path of Knowledge of the ground floor, a series of stone and lithoid materials as well as their related deterioration products from the interior rooms were sampled for analysis. The investigations covered a wide range of materials (plasters, mortars, natural and artificial stones, bricks, glass and finishings). They were carried out by means of a multi-analytical approach comprising SEM-EDX and optical microscopy; XRPD; XRF, ion chromatography; and Raman and infrared (FTIR) spectroscopies. The stones identified are linked to the Venetian architectural tradition (Euganean trachyte and Istrian stone). The sands in the mortars are mainly of regional origin and the glass is compatible with traditional Venetian (Murano) recipes. Of particular interest is the presence of an intonachino charged with ground fluorite. The deterioration products are linked to the extensive and intense phenomenon of capillary rising damp and efflorescence deposition induced by the lagoon environment. [ABSTRACT FROM AUTHOR]

Algerian Mzab traditional houses, using passive techniques since the eleventh century (from 1012 to 1882), have seen recent modifications. Analysis of 612 questionnaires and interviews with Mzab residents reveals 81.2% of these houses have been modified. Modifications include adding floors, thinning walls, and replacing lime with cement, driven by the need for space, ventilation, and modernisation. However, such modifications often increase energy consumption, with residents requiring more heating in winter and air conditioning in summer. This reliance on fossil fuels exacerbates regional climate insecurity. Planting roof terraces and using high-insulation building materials can reduce energy consumption in modified Mzab houses. [ABSTRACT FROM AUTHOR]

Wood is a sustainable, benign, and high-performing green structural material readily available in nature that can be used to replace structural materials. However, insufficient mechanical performance (compared to metals and plastic), moisture sensitivity, and susceptibility to microorganism attack make it challenging to use wood as it is for advanced engineering applications. We here present an efficient approach to fabricating densified wood with minimal time and waste generation, demonstrating high mechanical strength, and decreased water penetration on the surface. Wood slabs were treated with deep eutectic solvents (DESs) to solubilize the lignin, followed by in-situ regeneration of dissolved lignin in the wood. Then, the slabs were densified with heat and pressure, turning the wood into a functionalized densified material. Lignin regeneration and morphological changes were observed via two-photon microscopy and Scanning Electron Microscopy (SEM), respectively. The final product is less susceptible to water absorption on the surface and has enhanced flexural strength (> 50% higher), surface hardness (100% increased), and minimal set recovery compared to natural wood. The improved mechanical performance is due to regenerated lignin which acts as a glue and fills spaces present within the interconnected cellulose network inside the wood, forming a highly dense composite during densification. Such enhancement in the properties of DES-densified wood composite makes it a favorable candidate for advanced structural and engineering applications. [ABSTRACT FROM AUTHOR]

This study focuses on the use of bio-based materials for structural purposes in the packaging field, which requires the identification of their mechanical properties at a representative scale. The mechanical properties of bio-based materials are more variable than those of traditional composite materials. In a standard characterization approach using elemental coupons under uniaxial loading, the variability depends on the chosen representative elementary volume (REV), free edges, boundary conditions, etc. for elastic properties that are not identified for representative working conditions; this could lead to the ineligibility of these bio-based materials as structural materials. This paper contributes to the debate on how to study the response of bio-based materials within a structure, here a packaging structure as a logistic unit (LU) subjected to a compressive load simulating storage and stacking conditions. In the set of tools and methods for the design of packaging materials made of bio-based materials, an elastic nonlinear geometric finite element model (FEM) and an experimental approach are presented. The FEM allows the numerical identification of zones of interest within the LU. Inevitably, the FEM classically requires input data which are elastic properties of the equivalent homogeneous material. The design of the FEM is based on a calculation-test approach using an existing reference LU and it can be summarized in two main steps. The first step concerns the development of a FEM able to restore the experimental conditions of vertical compression imposed by transport standards for packaging. The second step is based on updating the input properties of the FEM by reverse identification, to achieve the representative working condition properties, using experimental results obtained on the existing reference LU. For the reverse identification a multi-scale investigation is mandatory. For this purpose, the linear elastic part of the load/vertical displacement curves (at the LU stiffness scale) and the displacement and strain fields measured (at the local LU scale) by 3D digital image correlation (3D DIC) are evaluated. Then, FEM property updating is carried out by reducing the deviation of displacement/strain fields between FEM and experimentally measured results (3D DIC). Finally, we explain how FEM and 3D DIC help in decision-making by allowing the recognition of zones of interest in a phase of design of new LUs with the concept of Multi-Instrumented Technological Evaluator (MITE). [ABSTRACT FROM AUTHOR]

Thanks to the reinforcing and toughening of carbon fiber, carbon fiber reinforced mullite (C/Mullite) composites exhibit favorable application potential as thermal structural materials. To further reveal the failure mechanism of the C/Mullite composites in service environment, the oxidation resistance and failure behavior of the composites were systematically investigated in this study. It was found that the oxidation mechanism of the composites inclined to diffusion control at 1300 °C∼1500 °C, the cracks and pores of the composites provided diffusion channels for oxygen to oxidize the composites, the oxidation degree of carbon fibers and interfacial coating after oxidation was responsible for the weight loss and performance degradation of the composites. Additionally, the oxidation resistance of C/Mullite composites can be obviously enhanced by using the SiO 2 -rich (the Al/Si atomic ratio was 1/2) Al 2 O 3 –SiO 2 sol to densify at the later stage of fabrication, strength retention and modulus retention of the composites were increased by 28 % and 40 % after oxidation at 1500 °C in air, respectively. [ABSTRACT FROM AUTHOR]

End-of-life tire (ELT) rubber has been widely researched to replace aggregates in construction materials such as asphalt concrete and cementitious composites. Although most studies paid attention to its effect on engineering properties and the durability of the materials, very few considered chemical reactions with pore solution and the potential for environmental leachate, especially rubberized stabilized soil, which was proposed recently to increase the use of ELT rubber in civil engineering. This study proposes the use of rubberized stabilized soil (RSS) in which clayey soils (e.g., kaolin and bentonite) were stabilized by portland cement (PC) and end-of-life tire (ELT) rubber particles. The authors previously developed a methodology to extract zinc from the ELT rubber; therefore, this study explores the potential for RSS to immobilize the leachate from the ELT rubber before and after this treatment. Three main topics are addressed in this study: (1) the capability of clay to capture leached zinc under ambient and alkaline aqueous conditions; (2) engineering properties of RSS [i.e., unconfined compressive (UCS), flow] with 0%, 10%, 30%, and 50% ELT rubber added by clay volume; and (3) pore solution and leachability tests of RSS. A leaching experiment was employed for Topic 1, UCS and flow tests were conducted for Topic 2, and pore solution extraction and leaching tests were performed for Topic 3. The results showed that the clayey soils and ELT rubber are synergistic in terms of engineering properties and the capturability of zinc and total organic carbon (TOC). Although the ELT rubber and PC strengthen the clay structure, the clay absorbs leached zinc and TOC from the ELT rubber particles. Adding untreated ELT rubber into PC-stabilized clays significantly increased the RSS strength; however, this improvement was less significant for the treated ELT rubber. Ultimately, the results proved that the environmental and mechanical performance of RSS makes it a viable construction material. [ABSTRACT FROM AUTHOR]

Rebars are among the main materials used in reinforced concrete structures and among the costliest and most carbon-intensive construction materials. However, during the construction phase, rebar cutting schemes are usually not rationalized enough and may lead to up to 8% waste. Previous studies and practices showed that obtaining data on rebar cutting can be labor intensive and imprecise, lacking the profiling of quantity take-off factors. Additionally, existing optimization techniques often do not adequately consider field characteristics, such as the number of cutting patterns and the scale of the problem, and the characteristics of the cutting data. This study proposes a practical, integrated approach for minimizing rebar cutting waste during the construction phase. The proposed approach consists of two main parts. The first part is obtaining rebar cutting data based on building information modeling (BIM). In this paper, the main influencing factors of rebar quantity take-off are analyzed, and the modeling hierarchy is divided based on these factors to obtain accurate cutting data. The hierarchy also reflects repeatable commonalities between different rebar systems, which helps reduce repetitive modeling efforts and increase efficiency. In the second part, a cutting pattern-oriented multiobjective optimization method is proposed to optimize the cutting scheme. The process is divided into three stages: generating valid cutting patterns, optimizing their frequency, and combining a small number of remaining components. The method combines three algorithms—column generation, particle swarm optimization, and best-fit decreasing—to solve the problem according to the characteristics of each stage. The influence of multiobjectives on the final optimization result is further explored through a sensitivity analysis. The integrated approach was validated with test sets of different sizes, types, and complexities. Its effectiveness and generalizability in reducing rebar cutting waste contribute to its applicability and the achievement of construction sustainability goals. Practical Applications: Rebars are among the main materials used in reinforced concrete structures and among the costliest and most carbon-intensive construction materials. Due to the extensiveness of the construction management mode, rebar has inevitably become one of the main sources of construction waste. However, due to the lack of practical optimization methods, this percentage can reach 5%–8% or even higher. This study proposes a practical approach for minimizing rebar cutting waste during the construction phase. In this paper, the main influencing factors of rebar quantity take-off are analyzed, and the modeling hierarchy is divided based on these factors to obtain accurate cutting data. Then, the cutting patterns are optimized, including generating valid cutting patterns, optimizing the frequency of the cutting patterns, combining a small number of remaining components, and organizing them into cutting schemes. The integrated approach provides a flexible perspective for solving this problem. The approach was tested for its generalizability and adaptability in various construction scenarios using test sets of different sizes, types, and complexities. The effectiveness of the approach in reducing rebar cutting waste, combined with the consideration of field characteristics and engineering habits, contributes to its applicability and the achievement of construction sustainability goals. [ABSTRACT FROM AUTHOR]

Within the new generation of structural materials having heterogeneous microarchitectures, one of the top performers is harmonic structure (HS). Herewith, the exciting discovery of self‐similarity in their stress–strain behavior is reported. HS materials consist of the 3D skeleton of ultrafine grains (UFG) encompassing coarse‐grained (CG) counterparts. Our discovery simplifies the mathematical description of such a system and helps unraveling hidden patterns. Specifically, it is demonstrated that overcoming the strength–ductility trade‐off in HS occurs since its components have a characteristic strengthening mechanism, which realizes the synergy of three factors: 1) hetero‐deformation‐induced (HDI) strengthening of the CG phase, the deformation of which increases with acceleration with respect to the deformation of the entire sample; 2) the transition of the CG phase to the strengthened to saturation UFG phase; and 3) the work of UFG phase deformation, which increases with acceleration when the sample is strained due to the rapidly growing value of γUFG*$\gamma_{\text{UFG}}^{\star}$ and the factor (2). [ABSTRACT FROM AUTHOR]

The objective of this research is to develop a composite polymer coating with increased thermal conductivity and corrosion resistance for protecting structural materials in heat exchange apparatuses. Chemically pure compounds such as graphene, boron nitride, tyrosine, sodium hydroxide, zinc pyrophosphate, ethyl acetate, and epoxy resin with the addition of secondary polypropylene were utilized as raw materials. The obtained coatings were evaluated using an emission scanning microscope equipped with an energy‐dispersive spectroscopy (EDS) detector. Electrochemical activity was measured using standard equipment within a frequency range of 0.1–0.01 Hz. Thermal conductivity and corrosion resistance were measured at 0.24 W/m K and 9.70 Ω/cm2 when using only epoxy resin with the addition of secondary polypropylene. When employing a composite consisting of epoxy resin with the addition of secondary polypropylene, boron nitride, graphene, tyrosine, and zinc pyrophosphate, the thermal conductivity and corrosion resistance values were 1.65 W/m K and 11.10 Ω/cm2, respectively. Polymer coatings containing 30% composite demonstrated the highest thermal conductivity (1.65 W/m K) and corrosion resistance (11.20 Ω/cm2). The research findings can be utilized to create polymer coatings with enhanced thermal conductivity and corrosion resistance values. This polymer coatings could serve as structural materials for heat exchange devices. Highlights: Corrosion resistance increase with complexing of composite coating.Thermal conductivity increase with complexing of composite coating.Use of epoxy resin with secondary polypropylene make thermal conductivity value. [ABSTRACT FROM AUTHOR]

Combustible and noncombustible notions have evolved with time, along with the associated fire tests by which legislation classifies building materials. New Zealand, Japan, and Europe are just some of the many legislations that have followed this evolution, except for North American regulations, which remain attached to methods dating back to 1944. To better understand this stagnation in North American practices, this document first traces the evolution of Canadian regulations on fire classification of materials. Then, a parallel is drawn with the evolution of reaction to fire tests mandated in the National Building Code of Canada. Finally, this paper will review the current fire classification of materials concerning the combustibility concept based on the Steiner tunnel test and the flame spread rating criteria. The analysis reveals that the relevance of the test and its results are questionable, and the reciprocity between test measurement and its classification does not always coincide. Despite the revisions made through time, the classification of materials based on their fire properties remains distinctly binary. [ABSTRACT FROM AUTHOR]

Compatibility tests are carried out on Ni-based Hastelloy alloys and stainless steel under the influence of the molten chloride salt NaCl-CaCl2-CeCl3 to investigate the corrosion behavior of molten salts with structural materials. Weight change measurements before and after the reaction tests show that the Hastelloy alloys have better corrosion resistance than stainless steel. The effects of molten salt purification on the corrosion behavior in the Hastelloy alloys are explored. The composition of the reacting phases is identified from transmission electron microscopy analysis and the corrosion mode is homogeneous corrosion with Cr and Fe diffusion, followed by Mo and Ni elution. [ABSTRACT FROM AUTHOR]

This study examined the encapsulation of Bacillus sphaericus LMG 22257 spores in biopolymeric microcapsules (MCs) for use in cement mortar, with a focus on enhancing self-healing properties. Biopolymers, including alginate (ALG), chitosan (CTS), carboxymethyl cellulose (CMC), and ALG/CMC blends at various ratios, were employed to fabricate the MCs through ionotropic gelation and freeze–drying. The physicochemical properties of MCs, including size, morphology, and swelling behavior under simulated concrete conditions, were assessed. Among these, ALG/CMC-MCs exhibited superior characteristics and demonstrated the highest urea hydrolysis activity when incorporated into the mortar, indicating optimal spore protection. Despite an initial decrease in compressive strength, the ALG/CMC blend with an ALG:CMC mass ratio of 6:4 achieved a crack healing efficiency of 96.7% over 28 days under cyclic wet-dry conditions. These findings highlight the potential of biopolymer encapsulation for embedding functional microorganisms in construction materials, contributing to a more durable and sustainable infrastructure. [ABSTRACT FROM AUTHOR]

When 304 steel and T91 steel are used as high-temperature structural materials, the presence of Cr-rich M23C6 carbides significantly impacts their properties. In the case of 304 steel, the inhibition of carbide precipitation is achieved by increasing the proportion of Σ3 grain boundaries (GBs). Conversely, for T91 steel, the proportion of random GBs increases following recrystallization. As a result, carbides precipitate within the ferrite grains instead of at the martensitic boundaries. [ABSTRACT FROM AUTHOR]

Foaming or porous geopolymers can be utilized in various engineering applications, including heat and acoustic insulations, as well as passive fire protection in building materials. They are ecofriendly materials, as no significant production power is required. In this study, geopolymers possessing foaming features involving lightweight and porous materials were successfully created through the reaction of sodium hydroxide solution 6 M with powder of waste glass MG without/with rice husk (RH) 20 wt.% of heat treated (212, 420, and 600 μm) utilized as the foaming agent. The effect of rice husk ash (RHA) and various sizes of RH additives on the thermal treatment (volume and weight changes, percentage), compressive strength, and microstructure (pore content) was assessed. The results show swelling (foaming behavior) for MG‐N6, MGB‐N6, MGR212‐N6, and MGR600‐N6 at 550°C, unlike the MGR420‐N6 formula. Also, a high‐volume change (percentage) for MGR420‐N6 paste at 650°C was noticed. Additionally, foaming behavior (high volume expansion) appeared for all thoughtful pastes after treatment at 750°C. The weight loss for all specimens in the range of 10%–27% and a high percentage of weight changes for MGR400‐N6 and MGR600‐N6 were noticed. Low values of compressive strength (2.74–14.5 MPa) were recorded for all formulas studied. These synthesized materials, geopolymers containing glass waste and RH powder, resulting from this study, are highly recommended, mostly for thermal and acoustic insulation materials demanding lightweight, porosity, and low mechanical properties. [ABSTRACT FROM AUTHOR]

Copyright of Builder (1896-0642) is the property of PWB MEDIA Zdzieblowski sp.j. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fire growth rate of interior linings, furnishings, and construction materials is measured in full-scale fire tests such as the ASTM E84 Steiner Tunnel, the ISO 9705 room fire, and a passenger aircraft fuselage as the flame-spread rate, time-to-flashover, or time to incapacitation, respectively. The results are used to indicate the level of passive fire protection afforded by the combustible material or product in the test without providing any insight into the burning process. These large-scale tests require many square meters of product, are very expensive to conduct, and can exhibit poor repeatability–making them unsuitable for product development, quality control, product surveillance, or regulatory compliance. For this reason, smaller (0.01 m2) samples are tested in bench-scale fire calorimeters under controlled conditions, and these one-dimensional burning histories are correlated with the results of the two- and three-dimensional burning histories in full-scale fire tests by a variety of empirical and semi-empirical fire propagation indices, as well as analytic and computer models specific to the full-scale fire test. The approach described here defines the potential of a material to grow a fire in terms of cone calorimeter data obtained under standard conditions. The fire growth potential, λ (m2/J), is the coupled process of surface flame spread and in-depth burning that is defined as the product of ignitability (1/ E ign ) and combustibility (Δ Q /Δ E) obtained from a combustion energy diagram measured in a cone calorimeter at an external radiant energy flux q · ext (W/m2) above the critical flux for burning, q · burn . However, the potential for fire growth, λ≡ (1/ E i gn )(Δ Q /Δ E) is only realized as a hazard when the heat of combustion of the product per unit surface area, H c (J/m2), is sufficient to grow the fire. The dimensionless fire hazard of a combustible product of thickness b is therefore, Π = λ H c, while the fire hazard of the component materials is an average over the product thickness, π = Π/ b. The measurement of λ, Π, and π from combustion energy diagrams of heat release Q (J/m2) versus incident energy E (J/m2) is described, as well as a physical basis for a fire growth potential that provides simple analytic forms for λ in terms of the parameters reported in cone calorimeter tests. Experimental data from the literature show that rapid fire growth in full-scale fire tests of combustible materials occurs above a value of Π determined by the severity of the fire test. [ABSTRACT FROM AUTHOR]

Copyright of New Architecture is the property of New Architecture Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The major challenge for the construction industry is to design and produce sustainable construction materials that are efficient in their performance and can be affordable for construction projects. The objective of this study is to determine the viability of incorporating waste products such as sugarcane bagasse ash (SCBA) to produce concrete with polypropylene (PP) fibers. SCBA is an industry waste that has certain pozzolanic properties, however, it shows limited mechanical properties when used as a cement replacement. To improve the mechanical and durability performance, metakaolin (15%) and PP fiber (0.5%, 1%, and 1.5%) were incorporated in the SCBA blend as a ternary additive. Some of the important characteristics explored include compressive strength, tensile strength, density, water absorption, acid resistance, and sorptivity. The study reveals that the incorporation of 15% metakaolin in the composite enhanced the compressive strength by 7%, 8.2%, and 9.1% for PP fiber additions of 0.5%, 1%, 1.5%, while the acid resistance enhanced by 4%, 6% and 8% relative to the control mix for the same value of pp fiber. Furthermore, cost evaluation confirms that the overall costs of concrete with 15% metakaolin and 5% SCBA were 12.2% less than the control concrete, thus making this option economically feasible. This research proves that the inclusion of SCBA, metakaolin, and PP fibers into the concrete mixture brings a sustainable approach that enhances mechanical properties and durability while assisting sugar manufacturing plants in the proper disposal of wastes. [ABSTRACT FROM AUTHOR]

Rapid industrialization and urbanization result in atmospheric pollution with trace elements precipitated and deposited by rain, affecting human health. This study determined the concentrations and non-carcinogenic and carcinogenic risks associated with trace elements in rainwater in the vicinity of the Ashaka cement factory. Samples were collected using a bulk sampler fitted with a high-density polythene funnel. A total of 140 samples were collected in 2020 and analyzed for 15 trace elements using ICP-OES. Multivariate analysis was used to identify the sources of the rainwater trace elements. The results show that the abundance of trace elements in the collected samples was in the following order: Fe > Sb > Cu > Ba > V > Sc > Sr > Mn > Zn > Ti > Hg > Al > Mo > Co. Crustal enrichment factors (EFc) indicated that the samples were extremely enriched with Hg, Sb, Cu, and Mo, moderately enriched with Zn, Ba, V, Co, Sr, Cr, and Sc, and unenriched with Fe, Mn, Ti, and Al. Chronic daily intake (CDI) for both the ingestion and dermal pathways was in the order Fe > Cu > Ba > Cr > V > Mn > Zn > Hg > Mo. The hazard index (HI) was > 1 through the ingestion pathway, indicating a likely non-carcinogenic advertising effect. Similarly, the carcinogenic risk (CR) exceeded the (1.0 × 10–4—1.0 × 10–4) acceptable limit for children and adults, indicating the likely development of cancer among consumers. This revealed that the elements present in rainwater are anthropogenic and are brought about by cement production. [ABSTRACT FROM AUTHOR]

With the upgrade of aircraft and the increasingly harsh service environment, it is urgent to develop high-performance thermal structural materials. In this study, inspired by foliar and root water uptake of trees, we propose a one-step facile method to achieve an autonomous gradient in C/C–ZrC–SiC sharp leading edge composites. The gradual increase of SiC content from top to bottom is beneficial to improve the heat transfer capacity of the composites. After oxyacetylene ablation for 60 s, the mass and linear ablation rates of the samples with gradient structure are 0.83 mg/s and 0.5 μm/s, 35 % and 83 % lower than conventional samples. The composites with gradient structure of ZrC and SiC are favorable to the formation of a compact and smooth ZrO 2 oxide protective layer, which not only protects the composites from further penetration of O 2 , but also resists the mechanical denudation. The novel gradient structure composites with enhanced ablation resistance show a bright application prospect in next-generation thermal protection systems. [ABSTRACT FROM AUTHOR]

Translation abstract Investigating natural rubber latex (NRL) composites through compressive testing for renewable and sustainable building materialsThis article explores the innovative use of natural rubber latex (NRL) as a fundamental component in the development of sustainable and renewable composite building materials, particularly focusing on incorporating wood chips as reinforcing particles. The study investigates the compressive mechanical properties of various composite formulations, analysing the influence of NRL contents and particle types – considering different wood species, shapes and sizes. Key factors such as particle geometry, NRL content, and sample preparation methods are identified as crucial factors in enhancing the mechanical properties of these composites. The results show that NRL composites exhibit distinctive characteristics like non‐linear behaviour, hysteresis, stress relaxation, and the Mullins effect during compression tests. The significance of these composite materials in construction is heightened by their potential to utilize NRL sourced from plants other than rubber trees, such as dandelions, thus advancing sustainable construction practices. This research aims to focus attention on exploring new, flexible, and highly customized composite materials by utilizing natural fibres and NRL across a range of construction applications. [ABSTRACT FROM AUTHOR]

Al–Li alloys, characterized by their lightweight and high strength, are essential structural materials in aerospace industry. Unraveling the atomic mechanisms that enhance the modulus of Al–Li alloys is key to developing the next-generation alloys. Utilizing first-principles methods, we systematically explored the influence of alloying elements on mechanical properties, ranging from binary solid solutions to Al3X precipitates and extending to ternary Al–Cu–Li alloys. Li significantly improves the modulus due to its size effects, low density, high solubility and easy precipitation. In binary A–Li solutions, the formation energy decreases (− 0.007 to 0.030 eV/atom) and the Young's modulus rises (80.2–88.4 GPa) as Li concentration increases (0–12.5 at.%). This increase in modulus is due to the compression of Al–Al bonds by Li atoms. The binary Al3Li phase, with reinforced bonds and lower density, exhibits a higher specific E modulus (49.2 GPa/g cm−3). In the ternary phase T1 (Al6Cu4Li3), the synergistic strengthening of both Al–Al and Cu-X (X = Al, Cu) bonds results in an elevated Young's modulus of 120.3 GPa, establishing it as a pivotal strengthening phase for the third-generation alloys. Subsequent theoretical calculations show superior elastic modulus in Al-X (X = Be, Si, Cr, Mn, Ni) solutions and Al3X (X = Sc, Ti, V, Zr) phases. Additionally, Zn can participate in the precipitation of the T1 phase, thereby enhancing the mechanical properties of the alloy. Gaining insights into atomic interactions and their influence on the modulus could inform the future design and optimization of multi-element Al–Li alloys. [ABSTRACT FROM AUTHOR]

Research on the sustainable production of building materials has been increasing from time to time. The construction industry is one of the sectors that leads to the depletion of significant amounts of nonrenewable resources, such as minerals. The ecosystem is deteriorated, and carbon dioxide (CO2) emissions are enormous in the environment due to the use of fossil fuel-based materials. The purpose of this paper is to review the use of plant fibers (hereafter NF) for reinforcement in cementitious concrete. Concrete, plant fibers, their chemical nature, and characteristics are highlighted in an overview. The most important issues in NF-concrete compatibility were discussed, which could provide research opportunities. Modification of NFs and the cement matrix are examined as methods for improving compatibility and degradation. Moreover, the properties and longevity of cementitious materials that are reinforced with natural fibers are also examined. Finally, the review emphasizes the significant research gaps and future research prospects identified in the reviewed papers. [ABSTRACT FROM AUTHOR]

As demand for sustainable building materials rises, the use of waste rubber in civil engineering is gaining attention. This study proposes a method to modify waste rubber using polyvinyl alcohol (PVA) to enhance its material properties and expand its applications. A dataset was created focusing on the mechanical strength of cementitious materials incorporating PVA-modified waste rubber, and multiple machine learning methods were used to develop regression prediction models, particularly evaluating the support vector regression (SVR) model. Results show that the SVR model outperforms others, achieving mean squared errors of 1.21 and 0.33, and mean absolute errors of 2.06 and 0.15. Analysis indicates a negative correlation between waste rubber content and the water-to-cohesive ratio (w/c) with strength indexes, while a positive correlation exists between curing age and PVA. Notably, waste rubber content significantly affects strength. The mechanical strength of cementitious materials was notably enhanced by PVA-modified waste rubber, likely due to PVA's dispersion and bridging effects. This study presents a novel approach to sustainably recycle waste rubber, highlighting its potential in construction materials. [ABSTRACT FROM AUTHOR]