Bituminous Geomembrane (BGM) in hot climates for hydraulic construction

Bio-Facades; An Innovative Design Solution Towards Sustainable Architecture in Hot Arid Zones

Conventional passive cooling techniques provide limited benefits in extremely hot climates in southern Asia, characterised by high daytime and night temperatures and frequent climate-related disruptions, such as power cuts. This study proposes and demonstrates a novel low-energy and resilient cooling solution for extremely hot regions in southern Asia. The novelty lies in the combination of geothermal heat dissipation and latent heat storage, specifically designed for the particular conditions of extremely hot climates in Southern Asia; considering the influence of climate-related disruptions such as power cuts, whose frequency is increasing in the region; and using discomfort hours as an indicator to measure the passive survivability of buildings in the absence of air-conditioning (following the adaptive comfort model). A numerical model was developed in TRNSYS for optimal sizing and configuration of the phase change material (PCM) integrated into a ceiling panel using a typical multi-family building archetype in three climatic regions of Pakistan. A parametric numerical analysis was performed concerning different PCM melting temperatures, amount of PCM, convective heat transfer capacity, and equivalent thermal conductivity. Moreover, daytime was considered the period with a higher probability of power cuts. The results showed how integrating PCM-based ceiling panels with geothermal heat dissipation can mitigate discomfort hours by 28 % in extremely hot climates, 55 % in very hot climates, and 91 % in hot climate areas with intermittent access to electricity. Latent heat storage maximised the benefits of geothermal heat dissipation by extending thermal comfort periods by 13 % and 18 % in extremely hot and very hot climates compared to the scenario without PCM. This low-energy resilient cooling solution, integrating PCM as a cool battery, can keep the home cool for longer when electricity is unavailable. This study demonstrates the importance of considering the specific climate-related disruptions from these extremely hot regions in building design, such as extreme heat events or power cuts, to enhance the heat resilience capacity of cities.

The aim of this research is to analyze thermal comfort and microclimate for indoor spaces in low-rise residential buildings in dry tropical climate. The study area is the municipality of Palmar de Varela in northern Colombia. The experimental methodology is based on measuring three microclimatic parameters: air temperature (Ta), relative humidity (RH) and natural ventilation (W). The study assessed the thermal sensation in indoor spaces based on Thermal Sensation Vote (TSV) and Predicted mean vote (PMV). Data gathered from surveys were analyzed with data mining technologies. The findings suggest that suspended ceilings and ceramic tiles aid to the thermal equilibrium of the building, resulting in a 1.1 °C decrease in indoor air temperature. Likewise, the correlation between temperature and wind (r = -0.72; -0.56) indicates that natural ventilation in buildings can alleviate thermal discomfort. Based on the thermal sensation evaluation, the predominant feeling reported by interviewees in indoor spaces was warm (2) in S1 and S2, and slightly warm (1) in S3. In addition, the correlation between air temperature and comfort sensation in indoor spaces (r = 0.64; 0.44) suggests that temperature has a direct impact on thermal sensation votes.

Compressed earth blocks (CEB) are an alternative to cement blocks in the construction of wall masonry. However, the optimal architectural construction methods for adequate thermal comfort for occupants in hot and arid environments are not mastered. This article evaluates the influence of architectural and constructive modes of buildings made of CEB walls and concrete block walls, to optimize and compare their thermal comfort in the hot and dry tropical climate of Ouagadougou, Burkina Faso. Two identical pilot buildings whose envelopes are made of CEB and concrete blocks were monitored for this study. The thermal models of the pilot buildings were implemented in the SketchUp software using an extension of EnergyPlus. The models were empirically validated after calibration against measured thermal data from the buildings. The models were used to do a parametric analysis for optimization of the thermal performances by simulating plaster coatings on the exterior of walls, airtight openings and natural ventilation depending on external weather conditions. The results show that the CEB building displays 7016 hours of discomfort, equivalent to 80.1% of the time, and the concrete building displays 6948 hours of discomfort, equivalent to 79.3% of the time. The optimization by modifications reduced the discomfort to 2918 and 3125 hours respectively; i.e. equivalent to only 33.3% for the CEB building and 35.7% for the concrete building. More study should evaluate thermal optimizations in buildings in real time of usage such as residential buildings commonly used by the local middle class. The use of CEB as a construction material and passive means of improving thermal comfort is a suitable ecological How to cite this paper: Ouedraogo,

The article discusses the design and construction of industrial facilities and civil buildings in hot and dry climate on the territory of The South of Russia. In the design of buildings in these areas must consider the flow of heat radiation from the Sun, especially in summer. When you create a comfortable environment in these regions the preference is for air conditioning and ventilation. To achieve comfort, it is important to reduce the number of Windows and skylights. To avoid overheating, it is necessary to have knowledge about the characteristics of building materials. Choice of construction material should be based on its thermal properties, and consequently on the time lag of the heat flux. Dense heavy materials such as clay, brick and stone, have a very high heat-storage capacity: heating and cooling occurs slowly, therefore, in hot climates they have a big advantage, providing coolness in the room. The income source of heat and heat loss, which is often ignored by designers, are also large areas of glazing in buildings. Widespread use of large areas of glazing in buildings for dry hot climate led to the development of different types of sun protection devices.

BackgroundPhysical inactivity is a major public health concern, exacerbated in countries with a (sub)tropical climate. The built environment can facilitate physical activity; however, current evidence is mainly from North American and European countries with activity-friendly climate conditions. This study explored associations between built environment features and physical activity in global tropical or subtropical dry or desert climate regions.MethodsA systematic review of four major databases (Web of Science, Scopus, PubMed, and SportDISCUS) was performed. To be included, studies had to investigate associations between perceived or objective built environment characteristics and adult’s physical activity and had to be conducted in a location with (sub)tropical climate. Each investigated association was reported as one case and results were synthesized based upon perceived and objectively assessed environment characteristics as well as Western and non-Western countries. Study quality was evaluated using a tool designed for assessing studies on built environment and physical activity.ResultsEighty-four articles from 50 studies in 13 countries with a total of 2546 built environment-physical activity associations were included. Design (connectivity, walking/cycling infrastructure), desirability (aesthetics, safety), and destination accessibility were the built environment characteristics most frequently associated with physical activity across the domains active transport, recreational physical activity, total walking and cycling, and moderate-to-vigorous physical activity, particularly if multiple attributes were present at the same time. Very few studies assessed built environment attributes specifically relevant to physical activity in (sub)tropical climates. Most studies were conducted in Western countries, with results being largely comparable with non-Western countries. Findings were largely generalizable across gender and age groups. Results from natural experiments indicated that relocating to an activity-friendly neighborhood impacted sub-groups differently.ConclusionsBuilt environment attributes, including destination accessibility, connectivity, walking and cycling infrastructure, safety, and aesthetics, are positively associated with physical activity in locations with (sub)tropical climate. However, few studies focus on built environment attributes specifically relevant in a hot climate, such as shade or indoor recreation options. Further, there is limited evidence from non-Western countries, where most of the urban population lives in (sub)tropical climates. Policy makers should focus on implementing activity-friendly environment attributes to create sustainable and climate-resilient cities.

Urban green spaces provide substantial environmental, ecological, and cultural benefits, such as biodiversity preservation and enhancement of human well-being. Green spaces play a crucial role in improving environmental quality, reducing pollution, and mitigating the occurrence of dust storms and droughts in arid regions. Green spaces and afforestation enhance thermal comfort and mitigate the effects of sunlight on ground and wall surfaces. This research aims to investigate the effects of green areas and afforestation on environmental enhancement in urban areas characterized by hot and dry climates. It focuses on the roles of increased oxygen production, atmospheric cooling, reduction of carbon dioxide emissions, and the provision of shade through trees. Baghdad exemplifies a hot and arid environment, characterized by an extended summer extending seven months with temperatures exceeding 50°C. Two proposed models were developed for a virtual metropolis under actual climatic circumstances, featuring the peak summer temperatures to examine the effects of green spaces and afforestation on Baghdad. A simulation was conducted to evaluate the two virtual cities exhibiting distinct afforestation patterns utilizing ENVI-met Software (Version 2023). The simulation results indicated that the second proposed model, which allocates afforestation and green spaces to encompass open areas, significantly diminishes sunlight exposure to floors and roofs, achieving a sky view factor of less than 5 at 91%, in contrast to 43.2% in the standard model. The research concluded that it is essential to choose the appropriate type of trees and green spaces that provide shade and whose leaves and branches contribute to obstructing the passage of sunlight to the surfaces, which contributes to reducing thermal stress and improving thermal sensation in hot and dry areas.

Due to the inadequate attention given to daylighting in lecture rooms in tropical wet and dry climate, this study, using field measurement, evaluates combined daylighting strategies in three lecture rooms labelled LLH, BMS and ANB with distinct bilateral glass louvre windows, window floor ratio, orientation and shading strategies. It determines the difference in illuminance in varied sky conditions, and the relationship between the strategies. Results revealed that under the clear sky condition, combined strategies in LLH and BMS rooms were effective in illuminance performance except during evening hours while the one in ANB was ineffective. Both rooms recorded poor daylight uniformity. Similar performance was obtained under overcast sky but they produced effective daylight uniformity. An effective daylighting was obtained throughout the process in the intermediate sky condition, however, the strategy in ANB room was ineffective in the evening hours. Only ANB room had an effective daylight uniformity in the intermediate sky. The strategy in LLH room had a strong positive relationship with BMS’s. The strategy in LLH had a weak positive correlation with ANB’s, but ANB’s strategy had strong positive correlation with BMS’s. Overall, the study contributes to the performance of combined daylighting strategies in tropical wet and dry climate.

Mechanisms of asphalt cracking and concrete-asphalt debonding in concrete overlay on asphalt pavements

This paper presents a study on the temperature deformations of reinforced concrete elements in Uzbekistan’s arid and hot climate. The calculation of axis length and curvature for long-term alternating heating and cooling is essential for concrete and reinforced concrete elements in these conditions. The study’s findings can help engineers and construction professionals accurately calculate temperature changes in reinforced concrete elements in arid and hot climates, minimizing the risk of damage and reducing maintenance costs.

Sustainable construction materials for low-cost housing: Thermal insulation potential of expanded SBR composites with leather waste

The two types of friction course materials, including conventional porous asphalt and conventional polymer (SBR) modified porous asphalt, are commonly used on roads in Hong Kong. The dry mixing method was applied to produce the conventional polymer (SBR) modified porous asphalt as the materials produced in the local batching plant. Nowadays, the pre-blended polymer (SBS) modified porous asphalt is gradually introduced and used due to its superior durability performance. This paper presents the details of a laboratory programme to evaluate the three types of porous asphalts. The materials tested involves the three types of binders, including conventional penetration 60/70 binder, conventional polymer (SBR) modified binder and pre-blended polymer (SBS) modified binder, and their respective porous asphalts. The binder test results indicate that two polymer (SBR and SBS) modified binders have the smaller temperature susceptibility and exhibit the better performance in resisting ageing, rutting and fatigue than the conventional penetration 60/70 binder. They are more suitable to be used than the conventional 60/70 in the hot climate areas. The mechanical properties and durability performance of the three types of porous asphalts are judged by the value of stiffness modulus and the ability of resisting water damage, permanent deformation and rutting. Tests are conducted using Nottingham Asphalt Tester (NU-10), Nottingham Wheel Tracker and Humboldt Indirect Tensile Strength Tester. All testing specimens were fabricated by Superpave Gyratory Compactor (SGC). The testing results show that the polymer (SBS) modified porous asphalt exhibit the most satisfactory performance overall with respect to stiffness, axial permanent deformation, rutting, and good resistance to moisture damage among the three types of porous asphalts and will be

Exposure to high ambient temperature affects buffalo productivity significantly in hot climate areas. Till date, no data is available on the heat stress response of mammary epithelial cells (MECs) in buffaloes. The present work aimed to examine the long term temporal changes in mRNA expression pattern of various heat shock proteins (HSP) genes in buffalo MECs during heat stress condition. For the study, we utilized the primary mammary epithelial cells of riverine buffalo and were exposed to thermal stress condition at 42°C for one hour. The cells were subsequently allowed to recover at 37°C and harvested at different time intervals (30 min to 48hr) along with control samples (unstressed). All the HSP (HSP40, HSP60, HSP70, HSP90, and HSPB1) showed immediate induction in their expression after heat shock and remained upregulated at the later stages as well. Amongst these, HSP70 gene showed maximal induction in its expression while HSP40 was found to be second most abundantly expressed HSP. Our present data thus provides the strong clue about the responsiveness of buffalo MECs to heat stress suggesting its suitability as an in vitro model to understand the modulation of buffalo mammary gland expression signature in response to environmental heat load.

A large part of incident solar radiation on photovoltaic (PV) modules is converted into heat, leading to overheating and reduction of PV modules performance. The present work investigates the impact of rectangular aluminium fins (RAFs) and evaporative cooling represented by cotton wicks immersed water (CWWs) on the performance and thermal behaviour of the PV module. Results indicate that the evaporative cooling attained better cooling potential than RAFs, in which the PV module temperature was reduced by 22.3%, and the output power was enhanced by 73% thanks to continuous cooling of the PV module. A slight improvement in the PV module performance was observed with RAFs due to the increased heat transfer area, which reduced temperature by up to 6.7% and increased the output power of the PV module by up to 21.3 %. Exergy analysis shows a gradual increment of the electrical exergy and exergy efficiency using CWWs, which reduces the entropy generation of it more than RAFs. The study concluded that PV modules without cooling in hot climate areas may deteriorate their performance significantly.

Abstract. Historic monuments and buildings are critical cultural assets which cannot be presented by again by human beings. Longer affected by natural climate, environment and biological behavior (including human), resulting in damage and the need for repair. Therefore, UNESCO proposed periodic reporting and reactive monitoring in 2007, in order to achieve “early detection, early repair”. This study discusses about suitable preservation monitoring methods for Taiwan. To shed light on damage and impact factors of historical buildings and cultural relics, the study is based on impact and sensor, monitoring method, monitoring period and maintenance personnel in order to propose standard operating procedures of monitoring method. To reduce the rate of the human and sensor monitoring, with the long-term monitoring data analysis, it is calculated that 30 minutes is the best period of data collecting. Besides, the study is adopted regression analysis to select temperature variable only then calculate humidity variable function. This study provides a reference monitoring method for monitoring personnel and maintenance personnel, and establishes a long-term monitoring data based information for damage and destroy in the future. Monitoring period and maintenance personnel can follow the data based to find out the damage points and problems, to keep the value of cultural assets.