Search Results (106)

The spatial genes of rural settlements show a lot of different traditional settlement traits, which makes them a great starting point for studying rural spatial morphology. However, qualitative and macro-regional statistical indicators are usually used to find and extract rural settlement spatial genes. Taking Yubei Village in the Nanxi River Basin as an example, this study combined remote sensing images, real-time drone mapping, GIS (geographic information system), and space syntax, extracted 12 key indicators from five dimensions (landform and water features (environment), boundary morphology, spatial structure, street scale, and building scale), and quantitatively “decoded” the spatial genes of the settlement. The results showed that (1) the settlement is a “three mountains and one water” pattern, with cultivated land accounting for 37.4% and forest land accounting for 34.3% of the area within the 500 m buffer zone, while the landscape spatial diversity index (LSDI) is 0.708. (2) The boundary morphology is compact and agglomerated, and locally complex but overall orderly, with an aspect ratio of 1.04, a comprehensive morphological index of 1.53, and a comprehensive fractal dimension of 1.31. (3) The settlement is a “clan core–radial lane” network: the global integration degree of the axis to the holy hall is the highest (0.707), and the local integration degree R3 peak of the six-room ancestral hall reaches 2.255. Most lane widths are concentrated between 1.2 and 2.8 m, and the eaves are mostly higher than 4 m, forming a typical “narrow lanes and high houses” water town streetscape. (4) The architectural style is a combination of black bricks and gray tiles, gable roofs and horsehead walls, and “I”-shaped planes (63.95%). This study ultimately constructed a settlement space gene map and digital library, providing a replicable quantitative process for the diagnosis of Jiangnan water town settlements and heritage protection planning. Full article

This study focuses on the ancient buildings in Cicheng Old Town, a typical architectural heritage area in the Jiangnan region of China. These buildings are famous for their well-preserved Tang Dynasty urban layout and Ming and Qing Dynasty roof tiles. However, the natural aging, weathering, and biological erosion of the roof tiles seriously threaten the integrity of heritage protection. Given that current detection methods mostly depend on manual checks, which are slow and cover only a small area, this study suggests using deep learning technology for heritage protection and creating a smart model to identify damage in flat tiles using the YOLOv8 architecture. During this research, the team used drone aerial photography to collect images of typical building roofs in Cicheng Old Town. Through preprocessing, unified annotation, and system training, a damage dataset containing 351 high-quality images was established, covering five types of damage: breakage, cracks, the accumulation of fallen leaves, lichen growth, and vegetation growth. The results show that (1) the model has an overall mAP of 73.44%, an F1 value of 0.75 in the vegetation growth category, and a recall rate of 0.70, showing stable and balanced detection performance for various damage types; (2) the model performs well in comparisons using confusion matrices and multidimensional indicators (including precision, recall, and log-average miss rate) and can effectively reduce the false detection and missed detection rates; and (3) the research team applied the model to drone images of the roof of Fengyue Painted Terrace Gate in Cicheng Old Town, Jiangbei District, Ningbo City, Zhejiang Province, and automatically detected and located multiple tile damage areas. The prediction results are highly consistent with field observations, verifying the feasibility and application potential of the model in actual heritage protection scenarios. Full article

This article presents the results of research concerning a comprehensive analysis of the operation of tools used for forming ceramic roof tiles in the clay-based band extrusion process. The conducted studies demonstrated that key process parameters, such as extrusion pressure and the flow speed of the ceramic mass containing hard components, are crucial for the durability of the tools, significantly affecting their wear. The analysis of the formed mass revealed the presence of hard fractions, such as quartz, zircon, and garnet, which significantly contribute to tool abrasion. Among the tested hardening variants of NC11LV steel, the best results in terms of enhanced longevity were operational tools treated at 1020 °C and then tempered at 200 °C for two hours. These results were confirmed in both operational tests and the dry abrasion test, indicating high wear resistance. Additional hardening through nitriding further extended the tool’s lifespan. The greatest wear was observed in the tool made of Hardox 600 steel with an additional overlay weld, which was caused by improper welding techniques. Numerical modeling, particularly the mesh-free SPH approach, proved to be the most effective method for analyzing the ceramic mass extrusion process. Full article

This paper presents the development of two solutions for sandwich panels composed of a thin-layer alkali-activated composite (AAc) layer and a thicker insulation layer, formed by extruded polystyrene foam or expanded cork agglomerate (panels named AP_XPS or AP_ICB, respectively). The AAc combined ceramic waste from clay bricks and roof tiles (75%) with ladle furnace slag (25%), activated with sodium silicate. The AAc layer was further reinforced with polyacrylonitrile (PAN) fibers (1% content). The mechanical behavior was assessed by measuring the uniaxial compressive strength of cubic AAc specimens, shear bond strength, pull-off strength between the AAc layer and the insulation material, and the flexural behavior of the sandwich panels. The thermal performance was characterized by heat flux, inner surface temperatures, the thermal transmission coefficient, thermal resistance, and thermal conductivity. Mechanical test results indicated clear differences between the two proposed solutions. Although AP_XPS panels exhibited higher tensile bond strength values, the AP_ICB panels demonstrated superior interlayer bond performance. Similar findings were observed for the shear bond strength, where the irregular surface of the ICB positively influenced the adhesion to the AAc layer. In terms of flexural behavior, after the initial peak load, the AP_XPS exhibited a deflection-hardening response, achieving greater load-bearing capacity and energy absorption capacity compared to the AP_ICB. Finally, thermal resistance values of 1.02 m² °C/W and 1.14 m² °C/W for AP_ICB and AP_XPS were estimated, respectively, showing promising results in comparison to currently available building materials. Full article

Geopolymer mortar is an eco-friendly type of mortar that is mainly made of fly ash, slag, and sand as common precursors. Recently, the availability of these materials has become limited due to the huge increase in geopolymer constructions. This is aligned with the recent demand for recycling construction and demolition waste (CDW). In this study, brick waste (BW), ceramic tile waste (CTW), roof tile waste (RTW), and glass waste (GW) extracted from CDW were prepared in the following two sizes: one equivalent to the traditional geopolymer mortar binder (fly ash and slag) size and the other one equivalent to the sand size. The prepared CDW was used to partially replace the binder or sand to produce high-strength geopolymer mortar (HSGM). The replacements were carried out at rates of 25% and 50% by volume. The variety of mechanical and durability characteristics were measured, including workability, compressive strength, freezing/thawing resistance, sulfate attack, water sorptivity, and water absorption. Three curing conditions were applied for the proposed HSGM in this study, namely, water, heat followed by water, and heat followed by air. The results showed that the compressive strength of all HSGM mixes containing CDW ranged from 24 to 104 MPa. HSGM mixes cured in heat followed by water showed the highest 28-day compressive strengths of 104 MPa (when using 25% BW binder), 84.5 MPa (when using 25% BW fine aggregate), 91.3 MPa (when using 50% BW fine aggregate), 84 MPa (when using 25% CTW binder), and 94 MPa (when using 25% CTW fine aggregate). The findings demonstrated that using BW provided good resistance to freezing/thawing and sulfate attack. The water absorption of HSGM increased by 57.8% when using 50% CTW fine aggregate and decreased by 26.5% when using 50% GW fine aggregate. The highest water sorptivity of HSGM was recorded when 50% CTW fine aggregate was used. The use of CDW in HSGM helps reduce the depletion of natural resources and minimizes waste accumulation, enhancing environmental sustainability. These benefits make HSGM an eco-friendly alternative that promotes circular economy practices. Full article

The Amazon biome’s climate, with annual temperatures above 30 °C and humidity over 90%, poses challenges for building thermally comfortable structures without expensive cooling systems. This study developed a castor oil-based polyurethane (PU) composite with miriti fiber (Mauritia flexuosa) as a roof thermal blanket, comparing its performance to fiber cement, ceramic, and metal tiles. Measurements were conducted over 136 days at the Federal Institute of Education, Science and Technology of Pará, Campus Belém. From August to October 2022, the fiber cement tile (CT) showed average thermal reductions of 5.9475 °C, 6.13388 °C, and 6.37368 °C, while the FCT coating had more modest reductions of 3.6634 °C, 3.63291 °C, and 3.60598 °C. In November and December 2023, the PU/miriti coating reached the highest reductions, 18.64058 °C and 17.88021 °C. Meanwhile, FCT recorded lower values of 1.74124 °C and 1.74721 °C. Observations show fiber cement allowed the highest heat transfer, whereas a metal tile combined with the PU/miriti composite provided better thermal performance than fiber cement and ceramic, meeting standards approval. The findings highlight the PU/miriti composite’s viability for roofing in hot, humid climates where maintaining lower indoor temperatures is essential. By reducing reliance on mechanical cooling, this technology can foster sustainable, cost-effective building practices in the region. Full article

The environment continues to erode the roofs of ancient buildings in Longmen Ancient Town, posing a threat to the safety of villagers. Scientific detection and diagnosis are important steps in the repair and protection of historical buildings. In order to effectively protect cultural heritage, this study uses the YOLOv8 deep learning model to automatically detect damage on images of traditional residential roofs. The researchers constructed image data sets for the four categories of green vegetation, dry vegetation, missing tiles, and repaired tiles and then perform model training. The results show that the model is generally accurate for missing tiles (0.94 for missing tiles and 0.93 for repaired tiles), and it has a low false detection rate and a low missed detection rate. It does make some mistakes when it comes to green and dry vegetation in complex backgrounds, but the overall detection coverage and F1 score are better. This practical application shows that the model can accurately mark most target areas, especially for the recognition of high-contrast damage types. This study provides efficient and accurate technical support for the diagnosis of traditional roof structures and protection of cultural heritage. Full article

Hail causes damage to property, including roofs, automobiles, and crops, with an average annual loss of USD 850 million. In residential structures in the southern U.S., tile roofing systems are common due to their resistance to the impact of hail and their long service life. Commercial low-slope roof systems are equally prone to hail-strike damages as steep residential roof systems. The objective of this paper is to present a literature review, inspection protocol, and case studies on a comparative assessment of the hail threshold for built-up roof (BUR) and tile roof (TR) systems. More than 90 published papers determining the hail impact assessment of different roofing systems from 1969 through 2024 were studied and analyzed. This study develops a comparative hail damage assessment study between BUR and TR systems and provides detailed statistical data and hail thresholds for various built-up roof composition systems. In addition, the different failure modes and their causes, the characteristics of hail impacts, and the variables influencing the impact resistance of these roofing systems were examined using field studies. To better understand the effects, it is recommended that an intelligent model be developed to predict the hail resistance threshold of various configurations of BUR and TR systems with critical variables. Full article

This paper presents investigations concerning the thermal firebrand reaction due to its accumulation in the top of ceramic roof tiles, commonly applied to the exterior of dwellings in southern Europe. A large-scale fire experiment is conducted, wherein firebrands are placed above the tiles and temperature readings are taken from multiple layers of the building components. The selection of materials for the roof layer assembly was based on recommendations for either fire resistance or high temperature behaviour. The test follows the fire setup recommended in the California Building Code for firebrand deposition. This investigation will allow for a more accurate verification of the firebrand reaction in the roof, including the type of ignition, the creation of smoke and droplets, and even their mechanical ability to withstand elevated temperatures. Full article

The management of thermal environments in animal production facilities presents significant challenges, requiring continuous adjustments to meet animals’ physiological needs. This study evaluated the effects of green roofs on the thermal environment and comfort indices in small-scale poultry house prototypes, comparing facilities with and without green roof installations. The research tested various roof types (ceramic, fiber cement, and metal) combined with emerald grass (Zoysia japonica) green roof systems. Parameters measured included air temperature, relative humidity, internal roof surface temperature, Temperature and Humidity Index (THI), Black Globe Humidity Index (BGHI), Human Comfort Index (HCI), and Thermal Radiation Load (TRL) under both open and closed conditions. Results showed that green roofs reduced indoor air temperature by up to 2.4 °C in open prototypes and 10.6 °C in closed prototypes during peak heat periods. In combinations using green roofs with fiber cement tiles, internal roof surface temperature decreased by 24.0 °C in open prototypes and 27.0 °C in closed configurations. The implementation of green roofs resulted in THI reductions of 2.3 and 8.1 units in open and closed prototypes, respectively, BGHI decreases of 2.8 and 11.3 units, and TRL reductions of 21.0 W/m² and 74.0 W/m². HCI measurements confirmed improved thermal comfort conditions with green roof installations in both settings. This study concludes that green roofs effectively enhance the thermal environment by reducing bioclimatic indices during hot periods while maintaining stable conditions during cooler weather, thereby improving overall thermal comfort in animal facilities. Full article

The construction sector plays a key role in the growth of developing countries but faces major environmental challenges, such as greenhouse gas emissions and resource depletion. Life Cycle Assessment (LCA) is an essential tool for evaluating these impacts and promoting sustainable choices. However, its effective application is limited by the lack of local databases. This study introduces a systematic framework (LOCAL-LCID₂) for creating local Life Cycle Inventory (LCI) databases for developing countries. Its application is demonstrated in Burkina Faso’s (BF) context through a comparative LCA of commonly used materials, covering the cradle-to-gate stage. The methodology follows seven steps: (1) identification of materials, (2) data collection, (3) analysis of material and energy flows, (4) development of LCI database, (5) structuring the database using SimaPro 9.6.0, (6) calculation of environmental impacts via ReCiPe 2016 Midpoint, and (7) uncertainty analysis using the pedigree matrix and Monte Carlo simulation. The materials are categorized into two main groups (imported and locally produced) with five subcategories: materials for roofs, walls/structures, floors, openings, and others. The results show that for wall materials, concrete blocks have the highest Global Warming Potential (GWP), with 88.3% of CO₂ emissions attributed to cement, implying an urgent need to optimize cement use and explore alternative binders for sustainable construction. Stabilized earth blocks show intermediate GWP at 65% of concrete block emissions, while straw-stabilized adobe demonstrates the lowest environmental impact, suggesting significant potential for reducing construction’s carbon footprint through traditional material optimization. The importation of steel sheets and ceramic tiles shows high GWP due to their energy-intensive production processes and long-distance transport (4 to 40% of emissions), highlighting opportunities to reduce impacts through local manufacturing and optimization of supply chains. The diversification of BF’s energy mix through clean energy imports from neighboring countries decreases GWP by 26.9%, indicating that regional energy partnerships and renewable energy investments are key pathways for minimizing environmental impacts related to energy consumption in the construction industry. Finally, the uncertainty analysis reveals the need for primary data updates in the current LCI database, highlighting both data quality enhancement opportunities and future research perspectives for industrial process assessment. The methodological framework equips decision-makers in developing countries with tools to implement sustainable construction practices through strategic material selection and regional resource optimization. Full article

European non-residential buildings constructed before building energy codes consume more energy and resources than new buildings. Existing educational buildings comprise 17% of this outdated stock. These buildings can be retrofitted to create a conducive learning environment that can improve students’ comfort. The refurbishment of facades is a common solution to improve the energy performance of schools when the aim is to improve the daylighting comfort. This study develops a methodology to optimize facade renovation solutions including (1) preparation, (2) simulations of the simplified model using local shading, and (3) modeling a realistic optimized facade design. This study evaluates visual comfort by considering multiple-dimensional metrics such as useful daylight illuminance (UDI), annual sunlight exposure (ASE), illuminance uniformity, and the daylighting factor. The three parameters of the louvres on which this study focuses are the distance from the new facade to the exterior wall, the blade degrees, and slat spacing. The methodology was first applied to improve the facade proposal with reused roof tiles from the project Waste-based Intelligent Solar-control-devices for Envelope Refurbishment (WiSeR). The results illustrate that implementing these solutions efficiently improves the indoor visual comfort in the classroom while avoiding overheating issues. For a constant-gaps surface, a shading distribution with alternated gaps gives better results for the aforementioned light metrics. Specifically, the most suitable values are a 7 cm distance from the new shading system to the existing wall, slat degrees at 0, and louvre spacing at 21 cm. Full article

This research investigates the use of municipal solid waste cremated fly ash as a viable substitute for natural sand in building methodologies, with a focus on sustainability. The waste material is used in the manufacturing of concrete roof tiles that are combined with solar PV systems, providing advantages in terms of both thermal comfort and improved energy efficiency. These tiles exhibit thermal insulation prowess by effectively preserving a 2-degree temperature differential and collecting heat from solar panels to enhance their energy-production efficiency. In order to enhance performance even further, aluminium foil is strategically placed on all four sides of the roof walls. The foil acts as a reflector, redirecting solar energy towards the tiles, which leads to a 5% boost in power generation. Particular alignments, such as positioning in an east-west or north-south direction, result in further enhancements in performance of 4% and 3%, respectively. This comprehensive approach not only confirms the use of waste materials for environmentally friendly construction but also emphasizes their crucial role in promoting energy-efficient building methods. Full article

The rapid increase in plastic usage today poses a significant threat to our environment and the planet. It contributes to global warming and negatively impacts biodiversity. Most plastic ends up in landfills, where it can take up to 1000 years to decompose. Shockingly, only 9% of the plastic produced annually is recycled, while an astounding 2 million plastic bags are used every minute worldwide. This paper highlights the primary goal of plastic recycling, with a particular focus on using plastic to manufacture roof tiles. The motivation behind this approach is that everyone deserves a decent roof over their heads. To achieve this, a well-balanced mixture of waste polypropylene (PP), quartz sand, and fly ash minerals was utilized in producing plastic roof tiles. The research employed a hot press process to prepare samples of all composite materials, and no cracks or fractures were observed on the surface of these samples. The results of this innovative process exceed the standards set for most building materials in terms of both mechanical and thermal properties, demonstrating a compressive strength of 99.8 MPa, a flexural strength of 35.6 MPa, and an impact energy absorption of 7.93 KJ/m². Importantly, all samples exhibited zero percent water absorption, making these roof tiles ideal for insulation purposes. Additionally, the resulting roof tiles are lightweight and cost-effective compared to conventional options. Full article

This study investigates the utilization of 3D laser scanning, GPS, BIM and GIS technologies for safeguarding historical wooden structures. As a case study, it focuses on two historic Chinese wooden buildings, the Guanyin Pavilion and Tangwang Palace, renowned for their exceptional historical significance and intricate timber architecture. The Guanyin Pavilion was subjected to high-precision modeling and tilt monitoring, which found that certain columns had a maximum tilt angle of 0.7892°. Additionally, a general tilt tendency was seen across various structural elements. The measurements from the point cloud data exhibited an error range of ±10 mm. However, the relative errors in smaller components approached 2.5%, which necessitated regular verification through human measurements. Using GIS and BIM technology in Tangwang Palace facilitated the meticulous documentation and dynamic supervision of architectural components, encompassing historical development and present state. The maintenance records revealed persistent problems with the roof tiles and wooden beams, exposing structural vulnerabilities. During various maintenance intervals, it was observed that the roof tiles were frequently loose and separated, indicating potential flaws in the design or materials used. The application of these modern technologies enhances the effectiveness and precision of conservation efforts and provides a robust scientific foundation for the continuous monitoring and study of cultural heritage. Full article