It is architecturally accepted that glazing system is considered as the most fragile part of buildings in terms of energy indoor performance. It is the only part of the building which has direct ...solar gain due to the transparent materials. Consequently, this part of building envelope should reap high consideration by architects and engineers, particularly in regions where solar radiation is high. The research aims to investigate the influence of glazing to wall ratio in different microclimate regions in Saudi Arabia which has been introduced by the author hot dry, hot humid and moderate climates. The research has studied the most possible glazing ration in the region based on previous work 5%, 10%, 20%, 30% and 40% out of the external wall. The paper used computer modelling TAS EDSL which has been validated using field monitoring study. Moreover, globe thermometer be used in order to investigate the impact of student’s position with respect to glazing system. Finally, questionnaire will be utilised to obtain actual thermal comfort from students in the selected regions with maintaining the same PSBD. The study reveals that south and east directions are the worst in terms of gaining the maximum amount of heat in all the locations. The research suggest that glazing to wall ratio is recommended to be 10% in both climate conditions hot and dry and hot and humid.
Underground constructions (UGCs) have been used globally to accommodate a wide range of building usage, such as offices and shopping malls. Most of these constructions suffer from a lack of natural ...ventilation as well as daylight, as they are completely built under the surface of the earth. This has caused many issues related to discomfort, impacting the activity and the productivity of users. This study aimed to analyse the effect of the use of UGCs in hot regions, enhanced by partly elevated external walls which reach aboveground to ensure natural ventilation and daylight, with relatively small amounts of glazing to minimise the influence of solar heat gain. The study used a real built underground room with field measurements for indoor temperature and relative humidity. Moreover, the study used the computer tool EDSL TAS to simulate the performance of the model throughout the year after a field validation. It was concluded that the use of UGCs in hot climates should be encouraged as natural ventilation and daylight can decrease temperatures by 3 °C in summer, and the utilisation of evaporative cooling can cool the indoor environment by nearly 12 °C. Furthermore, heat transfer was highly affected by the external environment. It was found that the amount of heat transfer doubled in comparison between under and aboveground constructions. The use of small windows for ventilation caused high humidity, even in hot regions, during summer.
The concern regarding local responsive building design has gained more attention globally as of late. This is due to the issue of the rapid increase in energy consumption in buildings for the purpose ...of heating and cooling. This has become a crucial issue in educational buildings and especially in schools. The major issue in school buildings in Saudi Arabia is that they are a form of prototype school building design (PSBD). As a result, if there is any concern in the design stage and in relation to the selection of building materials, this will spread throughout the region. In addition to that, the design is repeated regardless of the climate variation within the kingdom of Saudi Arabia. This research will focus on the influence of the window to wall ratio on the energy load in various orientations and different climatic regions. The research will use the energy computer tool TAS Environmental Design Solution Limited (EDSL) to calculate the energy load as well as solar gain. During the visit to the sample schools, a globe thermometer will be used to monitor the globe temperature in the classrooms. This research introduces a framework to assist architects and engineers in selecting the proper window to wall ratio (WWR) in each direction within the same building based on adequate natural light with a minimum reliance on energy load. For ultimate WWR for energy performance and daylight, the WWR should range from 20% to 30%, depending on orientation, in order to provide the optimal daylight factor combined with building energy efficiency. This ratio can be slightly greater in higher altitude locations.
Nowadays, photovoltaic (PV) are considered a promising alternative solution as a clean energy source. The power output from the solar PV module is proportional to the amount of solar radiation ...received by its surface. Hence, the determination of the most convenient locations of PV systems is crucial to maximize their output power. In this paper, the most suitable sites of PV farms in Egypt are identified based on the multi-criteria decision-making (MCDM) technique using the geographic information system (GIS) software. Four categories have been taken into acount; location, environment, meteorology, and climatology, to select the suitable locations. Based on experts’ knowledge ten criteria belong to the main categiories have been weighted using the analytical hierarchy process (AHP) and combined in PV land suitabliltiy index which maped using GIS techniques. The conducted suitability map could be used to guiding installation of renewable energy projects in the future.
Concrete is widely used as a building material all over the world, and its use is increasing the demand of cement and sand in the construction industry. However, the limited resources and ...environmental degradation are driving scientists to develop alternative materials from vast volumes of agro-industrial wastes as a partial replacement for conventional cement. In the manufacture of concrete, cement is a major binding resource. This study looked into recycling agro-industrial wastes into cement, such as sugarcane bagasse ash (SCBA), coal bottom ash (CBA), and others, to create sustainable and environmentally friendly concrete. This study aims to see how the combined effects of agricultural by-product wastes affected the characteristics of concrete. SCBA is used to replace fine aggregate (FA) ranging from 0 to 40% by weight of FA, while CBA is used to replace cement content ranging from 0 to 20% by weight of the total binder. In this case, a total of 204 concrete samples (cubes and cylinders) are made using a mixed proportion of 1:1.5:3 and a water-cement ratio of 0.54. Workability, density, water absorption, and mechanical characteristics in terms of compressive and splitting tensile strengths were examined in this study. In addition, for each mix percentage, the total embodied carbon was determined. Workability, density, and water absorption were found to be considerably decreased when CBA and SCBA concentration increased. Due to the pozzolanic nature of CBA and SCBA, an increase in compressive and splitting tensile strengths were seen for specific concrete mixtures, and further addition of CBA and SCBA, the decrease in strength. The embodied carbon of SCBA has augmented the total embodied carbon of concrete, though it can be seen that C15S40, which comprises of 15% CBA and 40% SCBA, is the optimum mix that attained tensile and compressive strength by 3.05 MPa and 28.75 MPa correspondingly, with a 4% reduction in total embodied carbon.
One of the most important functions of buildings is to provide comfort with minimum reliance on energy consumption. Many research focuses on the physical part of the building, which has resulted in a ...lack of investigation considering design and configuration. After the announcement of the Saudi vision of 2030, which aims to improve building performance, the aim of this research is to investigate the influence of models and sub-models of complex architectural configurations in various climatic regions. This will not only have its impact in the kingdom of Saudi, but it will also benefit users and institutions globally. These models have not been investigated before in terms of energy performance and thermal comfort, which makes this research highly essential. The research will use TAS EDSL modelling, which is considered as one of the most powerful and advanced tools for predicting buildings' energy performances. It can be seen that in all regions, the relationship between the indoor temperature and relative humidity has an inverse pattern. Having high relative humidity will make it difficult to achieve indoor comfort temperatures levels for the users with higher indoor air temperatures. This might require an increase in the indoor air velocity by natural pressure or even by mechanical means, such as fans. It will be concluded that linear and radial shapes are not recommended for extreme regions, whether they be hot or cold.
Stone industry has generated about 200 million tons of marble waste by marble processing industries whether in the form of sludge or solid blocks. The accumulated marble wastes contaminate water and ...air and have harmful effects on human health, plants, and animals. This study focuses on exploring the uses of powder obtained by drying and grinding marble sludge waste, generated from marble manufacturing processes, as a mineral filler for other construction materials. First, physical characterization was performed on marble sludge. Second, the powder preparation process was presented. Thereafter, a set of tests was carried out to identify the chemical, mineralogical, and physical properties of marble powder. By doing so, tests such as chemical analysis, calcium carbonate content, and methylene blue test, as well as mineralogical characterization using X-ray diffraction (XRD), Atterberg limits, particle size analysis, densities, Blaine specific surface, hydraulic property, as well as reaction with admixture, cement, and activity index were conducted. In the last part of this work, the obtained powder properties are compared to the standards requirements to confirm its suitability as mineral filler. The test results showed that the obtained marble powder is too rich in calcite; it is poor of any clay minerals fraction; it is very well graded; it is not reactive; and it does not have any effects on concrete strength; consequently, it can be considered as a mineral filler.
This research study is performed on the self-compacting geopolymer concrete (SCGC) combining coal bottom ash (CBA) and metakaolin (MK) as a substitution for GGBFS alone and combined for analysing the ...fresh properties (slump flow, V-Funnel, and T50 flow), mechanical characteristics (compressive, splitting tensile and flexural strengths) and durability tests (permeability and sulfate attack test). Though, total 195 SCGC samples were made and tested for 28 days. It has been revealed that the consumption of CBA and MK as a substitution for GGBFS alone and combine in the production of SCGC is decreased the workability of SCGC while mechanical characteristics of SCGC are enhanced by utilizing CBA and MK as a substitution for GGBFS alone and combine up to 10%. In addition, the compressive, splitting tensile and flexural strengths were calculated by 59.40 MPa, 5.68 MPa, and 6.12 MPa while using the 5CBA5MK as a substitution for GGBFS in the production of SCGC after 28 days correspondingly. Furthermore, the permeability is decreased by growing the quantity of CBA and MK by the weight of GGBFS alone and jointly in the production of SCGC after 28 days. Besides, the minimum change in length of the SCGC specimen is recorded by 0.062 mm at 7.5MK7.5CBA while the maximum change in length is calculated by 0.11 mm at 10CBA10MK as a substitution for GGBFS at 180 days correspondingly. In addition, the embodied carbon is recorded reduce as the addition of CBA while it is getting higher when the accumulation of MK alone or combined with CBA in SCGC. Besides, response models for prediction were constructed and confirmed using ANOVA at an accuracy rate of 95%. The models' R2 fluctuated from 88 to 99%. It has been observed that the utilization of CBA and MK alone and together up to 10% as substitution for GGBFS in geopolymer concrete provides the best results therefore it is suggested for structural applications.
With an embodied carbon content of 0.93 kg CO2/kg, cement is an essential component of concrete. As the global demand for concrete construction is rising, research is being conducted to replace ...cement with supplementary cementitious materials (SCMs). A variety of SCMs are identified as having positive impacts on the concrete's compressive strength and embodied carbon. Coir Fibre Ash (CFA) is well known in SCM from existing research, but its use in concrete has not been investigated from an embodied carbon perspective before. The paper adopts an experimental methodology involving CFA as SCM at 3%, 6%, 9%, 12%, 15%, and 18% of 576 kg cement for each m3 of concrete. CFA was therefore added. The study aimed to find out the impact of the addition of CFA in concrete on compressive strength (CS), flexural strength (FS), splitting tensile strength (STS), and modulus of elasticity (MOE). The determination of embodied carbon was made, and RSM was used to develop the model with maximum accuracy. Samples were prepared for 7, 14, and 28 days. CFA was found to be positively affecting CS, FS, STS, and MOE till 9%, after which, because of the dominance of silica dioxide in CFA, it did not show any improvement. Embodied carbon was found to be decreasing with the increasing addition of CFA. RSM results followed by optimization provided highly validated equations for predicting the CS, FS, STS, and MOE of concrete by just using the value of CFA as SCM.
•Coir fiber ash (CFA) is used as a replacement for Portland Cement (PC) in concrete.•The use of CFA in concrete is reduced the usage of PC, embodied carbon, and producing sustainable environment.•Concrete compressive , tensile , and flexural strengths were tested using cubes, cylinders, and prisms respectively.•Mechanical properties of CFA concrete were analyzed by using response surface methodology for modeling and optimization.
•New design of wind catcher to improve indoor air quality.•Air speed ait inlet and outlets of new designed wind catchers.•CFD fluent and experimental study involved.•Curved shape of wind catcher ...investigation to flow of air.
Wind catchers used in various countries in Middle East and North Africa in order to improve indoor air environment and to reduce reliance on cooling load. However, nowadays they are used across the globe with modern shapes and advanced techniques. The study focuses on investigating new and innovative shapes of wind catchers to improve air speed indoors which will elevate indoor comfort and air quality in buildings. The study used computer modeling CFD and a real model experiment to conduct the study. The study highlighted that curved shapes have highest pattern of wind speed driven, especially curved shape with double inlets. In addition, the study showed that octagon shape has the lowest pattern of wind speed driven because of its various sides which prevent air to flow easily inside the tunnel.
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