Search Results (2,108)

The indigenous community of Quisquinchir, in Saraguro (Loja, Ecuador), is facing a process of transformation of the rural Andean landscape associated with internal and external migration, as well as the influence of foreign architectural models. The new buildings symbolize, in the collective imagination, modernity and progress; however, they are alien to the natural environment characterized by the practice of agricultural and livestock activities. Although previous studies have described the loss of Andean vernacular architecture, its recent evolution in clear typologies has not been systematized. The objective of this study is to assess the current state of traditional dwellings and understand how migration reconfigures the landscape, collective memory, building traditions, and cultural identity of their inhabitants. Based on direct observation, photographic and stratigraphic analysis, and secondary sources, five typologies were identified: traditional one-story, traditional two-story, hybrid one-story, hybrid two-story, and eclectic. This classification indicates the replacement of earthen walls with cement blocks in 37% of the dwellings and of tile roofs with zinc roofs in 29%. However, 35% of the houses retain their traditional morphology and materials. These results and their classification are fundamental contributions to the design of local public policies that generate adequate interventions respectful of the environment. Full article

High-entropy boride (HEB) ceramics combine ultra-high melting points, superior hardness, and compositional tunability, enabling service in extreme environments; however, difficult densification and limited fracture toughness still constrain their aerospace applications. In this study, metallic Ta was introduced into high-entropy (Ti_0.2Zr_0.2Hf_0.2Nb_0.2Ta_0.2)B₂ as both a sintering aid and a toughening phase. Bulk HEB-Ta composites were fabricated by spark plasma sintering to investigate the effect of Ta content on densification behavior, microstructure, mechanical properties, and high-temperature oxidation resistance. The results show that an appropriate amount of Ta markedly promotes densification; at 10 vol% Ta, the open porosity reaches a minimum of 0.15%. Hardness and fracture toughness exhibit an increase-then-decrease trend with Ta content, attaining maxima at 15 vol% Ta (20.79 ± 0.17 GPa and 4.31 ± 0.12 MPa·, respectively). During oxidation at 800–1400 °C, the extent of oxidation increases with temperature, yet the composite with 10 vol% Ta shows the best oxidation resistance. This improvement arises from the formation of a viscous, protective Ta₂O₅-B₂O₃ glassy layer that effectively suppresses oxygen diffusion and enhances high-temperature stability. Overall, incorporating metallic Ta is an effective route to improve the manufacturability and service durability of HEB ceramics, providing a composition guideline and a mechanistic basis for simultaneously enhancing densification, toughness, and oxidation resistance. Full article

Currently, resin polymer anchoring agents are widely used for bolting support in coal mine roadways to anchor the bolts to the surrounding rock mass. However, due to the relatively low strength of the resin anchoring agent itself, the required anchoring length tends to be excessively long. Based on this, this paper proposes the use of resin concrete as a replacement for resin. Compared to resin anchoring agents, resin concrete offers greater mechanical interlocking force with anchor rods, which can reduce the theoretical anchoring length. To systematically investigate the influence of factors such as the diameter and anchorage length of Glass Fiber-Reinforced Polymer (GFRP) bolt on the bond behavior between GFRP bolts and resin concrete, 33 standard pull-out tests were designed and conducted in accordance with the CSA S807-19 standard. Taking the 18 mm-diameter bolt as an example, when the bond lengths were 2D, 3D, 4D, and 5D, the average bond strengths were 41.32 MPa, 39.18 MPa, 38.84 MPa, and 37.44 MPa, respectively. This represents a decrease of 5.18%, 6.00%, and 9.39% for each subsequent increase in bond length. The results indicate that the bond strength between GFRP anchors and resin decreases as the anchorage length increases. Due to the shear lag effect, the average bond strength also decreases with increasing anchor diameter. Taking a 5D (where D is the anchor diameter) anchorage length as a reference, the average bond strengths for anchor diameters of 18 mm, 20 mm, 22 mm, and 24 mm were 37.44 MPa, 33.97 MPa, 32.18 MPa, and 31.50 MPa, respectively. The corresponding reductions compared to the 18 mm diameter case were 9.27%, 14.05%, and 15.87%. Based on the experimental results, this paper proposes a bond–slip constitutive model between the bolt and resin concrete, which consists of a rising branch, a descending branch, and a residual branch. A differential equation relating shear stress to displacement was established, and the functions describing the variation in displacement, normal stress, and shear stress along the position were solved for the ascending branch. Although an analytical solution for the differential equation of the descending branch was not obtained, it will not affect the subsequent derivation of the theoretical anchorage length for the GFRP bolt–resin concrete system, as structural components in practical engineering are not permitted to undergo excessive bond-slip. Full article

In the previous research that aimed to enhance the toughness and tribological properties of silicon nitride ceramics, a lignin precursor was added to the ceramic matrix, which achieved conversion through pyrolysis and sintering, resulting in a silicon nitride-based composite ceramic containing nitrogen-doped graphene quantum dots (N-GQDs). This composite material demonstrated excellent comprehensive mechanical properties and friction-wear performance. Based on the existing experimental results, the first-principles plane wave mode conservation pseudopotential method of density functional theory was adopted in this study to build a microscopic heterostructure model of Si₃N₄-based composite ceramics containing N-GQDs. Meanwhile, the surface energy of Si₃N₄ and the system energy of the N-GQDs@Si₃N₄ heterostructure were calculated. The calculation results showed that when the distance between N-GQDs and Si₃N₄ in the heterostructure was 2.3 Å, the structural energy was the smallest and the structure was the steadiest. This is consistent with the previous experimental results and further validates the coating mechanism of N-GQDs covering the Si₃N₄ column-shaped crystals. Simultaneously, based on the results of the previous experiments, the stress of the heterostructure composed of Si₃N₄ particles coated with different numbers of layers of nitrogen quantum dots was calculated to predict the optimal lignin doping amount. It was found that when the doping amount was between 1% and 2%, the best microstructure and mechanical properties were obtained. This paper provides a new method for studying the graphene quantum dot coating structure. Full article

Background: This technical note presents a methodological approach to agrichemical inventory documentation. It complements exposure assessments in field settings with time-restricted observational periods. Conducted in Michoacán, Mexico, this method leverages large language model (LLM) capabilities for categorizing agrichemicals from brief video footage. Method: Given time-limited access to a storage shed housing various agrichemicals, a short video was recorded and processed into 31 screenshots. Using OpenAI’s ChatGPT (model: GPT-4o^®), agrichemicals in each image were identified and categorized as fertilizers, herbicides, insecticides, fungicides, or other substances. Results: Human validation revealed that the LLM accurately identified 75% of agrichemicals, with human verification correcting entries. Conclusions: This rapid identification method builds upon behavioral methods of exposure assessment, facilitating initial data collection in contexts where researcher access to hazardous materials may be time limited and would benefit from the efficiency and cross-validation offered by this method. Further refinement of this LLM-assisted approach could optimize accuracy in the identification of agrichemical products and expand its application to complement exposure assessments in field-based research, particularly as LLM technologies rapidly evolve. Most importantly, this Technical Note illustrates how field researchers can strategically harness LLMs under real-world time constraints, opening new possibilities for rapid observational approaches to exposure assessment. Full article

Creating complex structures using multiple materials in additive manufacturing comes with a unique set of challenges, particularly when it comes to how the materials transition and bond together. This research looks at a new powder binning method for combining metal powders to create multi-material components in a single build, all produced on a standard Laser Powder Bed Fusion EOS M 290 machine. The study focuses on the size and quality of the resulting multi-material interfaces and how different scan strategies used affect the interface strength. The strength of the interface between different material pairings is evaluated for combinations of 316 stainless steel bonded to Inconel 718, Inconel 718 bonded to Inconel 625, and Inconel 625 bonded to 316 stainless steel. The Ultimate Tensile Strength (UTS) and interface region lengths were calculated to be 675 MPa and 1250 µm for 316L–IN718, 1004 MPa and 2500 µm for IN718–IN625, and 687 MPa and 2000 µm for IN625–316L, respectively. The findings show that the laser powder bed fusion material binning method is comparable to traditional methods, such as welding or directed energy deposition. This suggests that the new material binning method offers clear advantages when it comes to enabling complex geometry multi-material components while maintaining the strength and durability of the bonds between different metal materials found in traditional means. Further, optimization of scan strategies in the interface zones could play a significant role in improving the overall performance of these multi-material components, which is particularly important for industries such as aerospace, automotive, and energy production. Full article

McMahon Hall, an iconic Brutalist dormitory at the University of Washington, has become the site of an interdisciplinary experiment in cultural memory and machine-assisted storytelling. This article presents a method that combines remote sensing with AI-generated voices to produce a polyvocal narrative of architecture through the perspective of the building itself, its material (concrete), an architect, a journalist, and a bird. Drone photogrammetry and generated 3D models were combined with generative AI (text, image, and voice) to reconstruct the site digitally and imaginatively (AI-driven speculative narratives). Through speculative storytelling, the article and the project explore how cultural memory and perception of built heritage can be augmented by machines, offering plural perspectives that challenge singular historical narratives. The Introduction situates the work at the intersection of digital heritage documentation, AI storytelling, epistemology in machine learning, and spatial computing, emphasizing the perception of heritage through different actors. The Theoretical Framework draws on literature in photogrammetry for heritage preservation, polyvocal narrative, and knowledge frameworks of AI. The Materials and Methods detail the workflow: capturing McMahon Hall via UAV photogrammetry, producing a 3D model, and generating character-driven narratives with large language models and voice synthesis. The resulting multi-voiced narrative and its thematic insights are described. In the Discussion, the implications of this approach for architectural heritage interpretation are considered, including its capacity to amplify diverse voices and the risks of bias or hyperreality in AI-generated narratives. The study argues that this polyvocal, machine-augmented storytelling expands the toolkit of remote sensing and digital heritage by not only documenting the tangible form of the built environment but also speculating on its intangible cultural memory. The Conclusions reflect on how merging spatial computing techniques with AI narratives can support new modes of engagement with architecture, positioning this work as a building block toward richer human-machine co-created heritage experiences. Full article

Multicomponent concrete is a widely used industrial material, yet its performance evaluation still relies heavily on expert judgment and long-term monitoring. With the rapid development of artificial intelligence (AI), machine learning has emerged as a promising tool in building science for analyzing complex datasets and reducing uncertainties associated with human factors. This study applies a variety of machine learning techniques—including linear and polynomial regressions, tree-based algorithms (Decision Tree, Random Forest, ExtraTrees, AdaBoost, CatBoost, and XGBoost), and the TabPFN model—to investigate the key factors influencing concrete compressive strength. To enhance interpretability, SHAP analysis was employed to uncover feature importance and interactions, offering new insights into the underlying mechanisms of multicomponent concrete. The findings provide a data-driven approach to support engineering design, facilitate decision-making in construction practice, and contribute to the development of more efficient and sustainable building materials. Full article

The search for sustainable and economical alternative materials has become a top priority in response to the increasing scarcity of natural river sand resources; as a result, a new alkali-activated granulated blast-furnace slag (GGBS)/fly ash (FA) composite cement material innovatively using Tuokexun Desert sand as aggregate has emerged as a good strategy. In this study, GGBS/FA was used in place of cement; the effects of the water glass modulus, alkali equivalent, and FA content on the material’s properties were systematically studied, and the hydration reaction mechanism and durability characteristics were revealed. The material was found to form a stable calcium aluminosilicate hydrate (C-(A)-S-H) gel structure under a specific ratio, which not only displayed excellent mechanical properties (a compressive strength of up to 83.2 MPa), but also showed outstanding resistance to high temperatures (>600 °C) and acid–alkali erosion. Microscopic analysis showed that the phase transition behaviour of C-(A)-S-H was a key factor affecting the material properties under high-temperature and acid–alkali environments. This study provides a new method for the preparation of high-performance building materials using local materials in desert areas, which is of great significance for promoting the construction of sustainable infrastructure in arid areas. Full article

This study explores the transformative potential of cyber technologies in the preservation, representation, and restoration of architectural heritage. Bridging technical and humanistic dimensions, it examines how tools like Heritage Building Information Modeling (HBIM), As-Designed BIM, and Virtual Reality (VR) support deeper, multilevel, and multitemporal understandings of cultural sites. Central to the research is an experimental restoration project on the castles of Civitella in Val di Chiana (Arezzo), serving as a methodological testbed for a digitally integrated approach. Developed through a scan-to-BIM process, the project yields a high-fidelity immersive ecosystem—both a rigorous model for future restoration and a VR platform enabling access to previously unreachable spaces. Here, representation is not a secondary or illustrative phase but a central, operative component in historical interpretation and architectural design. This approach embraces cyber representation: a digitally mediated, interactive, and evolving form that extends heritage beyond its physical boundaries. The immersive model fosters renewed dialogue between past and present, encouraging critical reflection on material authenticity, spatial transformation, and conservation strategies within a dynamic, participatory, interactive webVR environment. Representation thus becomes a generative and narrative tool, shaping restoration scenarios while enhancing analytical depth and public engagement. The study ultimately proposes a shift in historical storytelling toward a polyphonic, experiential, cyber-mediated narrative—where technology, memory, and perception converge to create new forms of cultural continuity. Full article

Advancements in material technologies and increasingly stringent thermal insulation requirements are driving the search for innovative solutions to serve as an alternative to traditional insulating materials. Using 3D printing techniques to produce thermal insulation opens up new possibilities for creating structures, geometries, and shapes from a variety of raw materials, ranging from synthetic polymers to biodegradable composites. This study aimed to develop a modern thermal insulation barrier with a comparable thermal conductivity to conventional materials to enhance the energy efficiency of buildings. Cellular materials based on the Kelvin cell were fabricated using additive manufacturing via 3D SLS printing from a composite consisting of a biodegradable material (TPS) and a recyclable polymer (PA12). The printed cellular structural partitions were tested for their thermal insulation properties, including thermal conductivity coefficient, thermal transmittance (U-value), and thermal resistance. The best thermal insulation performance was demonstrated by a double-layer partition made from TPS + PA12 at a mass ratio of 5:5 and with a thickness of 60 mm. This sample achieved a thermal conductivity of λ = 0.026 W/(m·K), a thermal resistance of R = 2.4 (m²·K)/W, and a thermal transmittance of U = 0.42 W/(m²·K). Cellular partition variants with the most favorable properties were incorporated into building thermal balance software and an energy simulation was conducted for a single-family house using prototype insulating materials. This enabled an assessment of their energy efficiency and cost-effectiveness. Full article

This study compares the environmental impacts of building reconstruction and renovation in aging building improvement projects and quantitatively assesses their carbon reduction potential from a life cycle perspective. A life cycle assessment (LCA) methodology was used to estimate greenhouse gas emissions across all stages—production, transportation, construction, operation, and disposal. A reinforced concrete (RC) structure in Seoul served as the case study, with three scenarios modeled: maintaining the existing structure, reconstruction, and renovation. Results show that renovation produced a carbon emission intensity of approximately 1.37 × 10³ kg–CO₂eq/m²—46.21% lower than the existing building and 22.34% lower than reconstruction. Renovation offered significant embodied carbon savings during the production and demolition phases. In the operational phase, emissions were reduced by 47.50% through upgrades such as high-performance insulation, better windows, and renewable energy systems. While reconstruction showed some emission reductions, its environmental burden remained higher due to the need for new materials and additional demolition waste. Overall, renovation demonstrates greater carbon reduction potential across the building’s life cycle. These findings underscore its value as a key strategy for achieving carbon neutrality in the building sector by 2050 and provide scientific evidence to inform design and policy decisions. Full article

This article proposes a comparative framework for interpreting architectural and armorial artefacts through morphological and symbolic analysis. Focusing on the Romanesque, Gothic, and Renaissance periods, the study explores how buildings and body armour—though differing in scale and function—encode similar cultural values related to protection, identity, and representation. Rather than seeking direct historical transmission, the research reveals convergent design logics shaped by shared symbolic imperatives. Methodologically, the article combines typological comparison with embodied heritage practices. These include experimental reconstruction, traditional stone carving, and field-based conservation conducted through the Ambulance for Monuments (Ambulanța pentru Monumente) programme. Such experiences support a situated understanding of proportion, articulation, and material behaviour in both architecture and armour. By repositioning historical armour as a culturally meaningful artefact rooted in craft knowledge and symbolic logic, the study contributes to current debates in heritage science. It argues for the inclusion of martial objects within broader frameworks of heritage interpretation. The findings highlight how architecture and armour function as co-expressive elements of a shared design culture, offering new insights for research, conservation, and the communication of historical meaning. Full article

When iron oxide nanoparticles are incubated together with a biological broth, the biomolecules compete for the binding sites at the solid–liquid interface. At the same time, the biomass rearranges in suspension, building agglomerated structures. Despite general knowledge of the forces involved in bio–nano interactions, gaps remain in the understanding of how biomolecules organize themselves in solution and onto surfaces. This work examines biomolecule adsorption onto metal oxide surfaces with the goal of strengthening this understanding, essential in industrial and natural processes. We demonstrate nearly complete separation of proteins from a biotechnological suspension for non-oxidized and highly oxidized magnetic nanoparticles. Varying the nanoparticle-to-biomass ratio, we find, can lead to different separation patterns, i.e., that selectivity using bare, low-cost materials is possible. Furthermore, we explore how preliminary “passivation” with a biological corona only partially reduces the ability to separate total protein mass from a new suspension in subsequent incubation steps. The study underscores the crucial role of concentration gradients with regard to targets and binding sites as the primary determinant of separation capacity and of biomolecule behavior in solution, highlighting the potential for using bio–nano coronae as biomolecule carriers across diverse fields, including environmental, biomedical, pharmaceutical and nutritional applications. Full article

Construction and demolition waste (CDW) is the most significant portion of solid waste generated throughout the European Union (EU). CDW represents more than a third of the waste generated, considering the waste generated by all economic activities and household waste. The central reuse of CDW is as a base for roads, and in specific cases, it can be reused as recycled coarse aggregates (RA) in the manufacture of precast concrete, new building blocks, bricks, and as RA on new concrete formulations, among other activities. This work aims to enable the concentration of the aggregates mixed in the CDW with the jigging process. The recovered RA was replaced in the concrete, and four different replacement levels (25%, 50%, 75%, and 100%) were analyzed for reuse in new C30/40 concretes. Physical characterization of the material was performed, and compressive strength tests were conducted to verify the RA replacement’s influence on the concrete. The work tests allowed us to observe the positive variation of the material’s physical properties according to the jigging processing and the efficiency of recovering the aggregates. After analyzing the results obtained in the strength force tests, it is possible to conclude that the RA generated can be a substitute for natural aggregates (NA) in new C30/40 concrete formulations. When 100% RJA is used as a replacement, the 28-day compressive strength reaches 33.2 MPa, which is only 6% lower than that of the NA group, reducing the environmental liabilities inherent in the aggregate mining process and generating an economically viable material. Full article