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Laban, Mirjana, and Radomir Folic. "Energy efficiency of industrially made buildings influenced by thermal properties of façades." Thermal Science 18, no. 2 (2014): 615–30. http://dx.doi.org/10.2298/tsci120417147l.
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The main objective of this paper is to evaluate the thermal properties of existing residential buildings built in industrial manner in Novi Sad from 1960 to 1990 based on building typology. Each of three analyzed building type has its characteristic fa?ade, with thermal performances divided into periods according to the development of domestic thermal protection building codes. The necessary layer of subsequent insulation is determined by calculations in order to comply with European standards, also applied in Serbia from 2012. The proposed method of periodization simplifies the process of thermal performance assessment and it was checked through the case studies. Evaluation of energy consumption rationalization has been done through comparative analysis of energy losses. Based on the most common energy rehabilitation measures applied in Serbia, it was estimated that it was possible to reduce the energy losses in heating up to 60%.
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Ba, Labouda, Ikram El Abbassi, Cheikh S. E. Kane, A.-M. Darcherif, and Mamoudou Ndongo. "Thermal performance of biosourced materials on Buildings: The case of Typha Australis." MATEC Web of Conferences 330 (2020): 01011. http://dx.doi.org/10.1051/matecconf/202033001011.
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Developing countries are facing population growth, which leads, on the one hand, to increased requirements for buildings and, on the other hand, to the depletion of fossil fuels along with exposure, of people living in those areas, to some detrimental consequences of climate change. Because of these factors, we propose approaches to control energy consumption in buildings. In some countries, the architectures adopted are not adequate to the environment and climate, resulting in discomfort in those buildings, in such circumstances, residents resort to the use of energy systems, such as heating, ventilation, and air conditioning, which leads to exorbitant electricity bills. Housing consumes 40% of the world's energy and is responsible for a third of greenhouse gas emissions. Optimizing energy needs in buildings is a solution to overcome these problems. For this purpose, there are solutions such as: the design of the building characterized by its shape and envelope, while using less energy-consuming equipment. For several years, the building materials sector has been developing with a particular focus on bio-source materials, which are generally materials with good thermal performance. In order to highlight the thermal performance of bio-source materials, we will study the case of Typha Australis which is a plant of the Typhaceae family that grows abundantly in an aquatic environment mainly in the Senegal River valley.Recent studies showed that Typha Australis has good thermal insulation properties. In order to determine the impact of Typha Australis on a building, a dynamic thermal simulation was carried out using the Trnsys software according to specific scenarios, the Typha was mixed with other local materials and used as a wall insulation panel, the result of the study shows that this fiber has allowed us to optimize energy consumption in a building. Mixing Typha with other materials (e. g. clay) is a promising solution for energy efficiency in buildings.
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Zahiri, Sahar, and Hasim Altan. "Improving energy efficiency of school buildings during winter season using passive design strategies." Sustainable Buildings 5 (2020): 1. http://dx.doi.org/10.1051/sbuild/2019005.
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Passive building design can improve energy efficiency of buildings, while providing comfortable indoor environment for occupants with minimum mechanical energy use. The foundation of passive design depends on natural sources of energy, which uses building architecture and surrounding environment to minimise heating and cooling loads of buildings with minimum operating and maintenance costs. The correlation of local climate with shape and thermal performance of buildings is one of the main considerations of passive design approach to reduce energy use and increase thermal comfort of occupants. This paper focuses on a series of field studies and building simulation analysis to improve thermal performance of female secondary school buildings in the city of Tehran in Iran during winter season using passive design strategies. The field studies included measuring indoor air temperature, as well as a questionnaire-based survey in a cold winter season in a typical female secondary school building. The on-site monitoring assessed indoor air temperature of classrooms while the occupants completed questionnaires covering their thermal sensations and thermal preferences. Moreover, building thermal simulation analysis were carried out using DesignBuilder tool to evaluate and improve thermal performance of classrooms based on students' thermal requirements and passive design strategies. The simulation analysis started from the basic school building model, investigating various passive design strategies to predict the optimum design strategies for the case study. The simulation results determined how to provide classrooms that are more comfortable for students with minimum energy use. The results of the field studies indicated that indoor thermal environment were usually comfortable for female students based on 7-point ASHRAE scale. However, most of the occupants preferred their indoor thermal environment to be improved. Moreover, simulation results showed that building fabrics and thermal properties, as well as glazing and orientation had significant impacts on indoor air temperature and thermal comfort and using appropriate passive design strategies could improve energy efficiency of the building considerably. Therefore, in order to enhance indoor thermal environment and to increase learning performance of students, it is necessary to use appropriate low energy methods, which can reduce the needs for mechanical energy systems and hence save energy.
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Netinger Grubeša, Ivanka, Mihaela Teni, Hrvoje Krstić, and Martina Vračević. "Influence of Freeze/Thaw Cycles on Mechanical and Thermal Properties of Masonry Wall and Masonry Wall Materials." Energies 12, no. 8 (April 17, 2019): 1464. http://dx.doi.org/10.3390/en12081464.
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In this study, the influence of freeze/thaw cycles on the mechanical and thermal properties of bricks and mortar as building parts of masonry walls, as well as the influence on the masonry wall itself is investigated. At the material level, the influence of freeze and thaw cycles on the mechanical and thermal properties of masonry components (bricks and mortar) was investigated; at the construction level, the influence of freeze and thaw cycles on the mechanical and thermal properties of a masonry wall was studied. To study the influence of freezing on the energy demand characteristics of masonry buildings, in terms of energy conservation and greenhouse gas emission, a case study was investigated on a typical structure of a historical building located in Croatia, that had undergone a process of energy certification. The applied freeze/thaw regime negatively influenced the compressive strength and the thermal properties of bricks and mortar, as well as the mechanical and thermal properties of the wall. Considering the thermal properties of the material before and after its exposure to freeze/thaw cycles, we concluded that the annual energy consumption, the heating costs, and the CO2 emission of a family house could increase up to 3.7% after frost action in the studied case.
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Szkordilisz, Flóra, and Márton Kiss. "Potential of Vegetation in Improving Indoor Thermal Comfort and Natural Ventilation." Applied Mechanics and Materials 824 (January 2016): 278–87. http://dx.doi.org/10.4028/www.scientific.net/amm.824.278.
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According to the EPBD (2010) whilst improving the thermal performance of buildings good or at least tolerable thermal comfort conditions must be provided. But better thermal insulation and more airtight buildings increase the risk of summer overheating which makes mechanical cooling inevitable. This idea has been verified by the tendency of the last decade, when people were willing to install and use more frequently air conditioning devices during the summer heatwaves – increasing their energy consumption and electricity bills at the same time. We cannot neglect the importance of studies triggering an efficient way to minimise the cooling load of residential buildings by obstructing solar radiation. The usage of plants in front of transparent surfaces of the façade can avoid indoor overheating. Deciduous plants obstruct buildings’ solar access so that the microclimate around the building is improved too. The use of Green Infrastructure in different levels of planning processes, which would provide sustainable solutions for urban management, is also prescribed in the EU Biodiversity Strategy 2020. Of course in order to investigate the actual effect of trees on indoor thermal comfort we should take into consideration a list of other factors: such as orientation the type and thermal properties of the windows / transparent structures used, and the thermal transmittance values and heat storage capacity of the building. If we have taken into consideration the mentioned factors during simulation we can prove the effectiveness of vegetation for each case. Simulations are made on the base of transparency measurements carried out during the summer of 2014. The shading efficiency of trees is a species-specific attribute because of the varying crown structure and leaf density. Our analyses aimed at the quantification of the transmissivity of characteristic individuals of three frequently planted species (Celtis occidentalis, Sophora japonica, Tilia cordata). The measured data were the amount of transmitted shortwave radiation, compared with a measurement point under unobstructed sunlight. In preliminary studies we have shown that depending on species – a tree in front of the façade can decrease the solar gain on internal horizontal surface up to ~18-30 per cents. As the tree obstructs the solar access of the wall and that of transparent surfaces, a difference in indoor comfort is to be observed too.
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Moreno Santamaria, Belen, Fernando del Ama Gonzalo, Danielle Pinette, Roberto-Alonso Gonzalez-Lezcano, Benito Lauret Aguirregabiria, and Juan A. Hernandez Ramos. "Application and Validation of a Dynamic Energy Simulation Tool: A Case Study with Water Flow Glazing Envelope." Energies 13, no. 12 (June 19, 2020): 3203. http://dx.doi.org/10.3390/en13123203.
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The transparent materials used in building envelopes significantly contribute to heating and cooling loads of a building. The use of transparent materials requires to solve issues regarding heat gain, heat loss, and daylight. Water flow glazing (WFG), a disruptive technology, includes glazing as part of the Heating, Ventilation and Air Conditioning (HVAC) system. Water is transparent to visible wavelengths, but it captures most of the infrared solar radiation. As an alternative to fossil fuel-based HVAC systems, the absorbed energy can be transferred to the ground through borehole heat exchangers and dissipated as a means of free-cooling. Researchers of the Polytechnic University of Madrid have developed a software tool to calculate the energy balance while incorporating the dynamic properties of WFG. This article has studied the mathematical model of that tool and validated its ability to predict energy savings in buildings, taking spectral and thermal parameters of glazing catalogs, commercial software, and inputs from the measurements of the prototypes. The results found in this article showed that it is possible to predict the thermal behavior of WFG and the energy savings by comparing the thermal parameters of two prototypes. The energy absorbed by the water depends on the mass flow rate and the inlet and outlet temperatures.
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Giro-Paloma, Jessica, Camila Barreneche, Alex Maldonado-Alameda, Miquel Royo, Joan Formosa, Ana Inés Fernández, and Josep M. Chimenos. "Alkali-Activated Cements for TES Materials in Buildings’ Envelops Formulated With Glass Cullet Recycling Waste and Microencapsulated Phase Change Materials." Materials 12, no. 13 (July 3, 2019): 2144. http://dx.doi.org/10.3390/ma12132144.
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Within the thermal energy storage field, one of the main challenges of this study is the development of new enhanced heat storage materials to be used in the building sector. The purpose of this study is the development of alkali-activated cements (AACs) with mechanical properties to store high amounts of heat. These AACs incorporate wastes from industrial glass process as well as microencapsulated phase change materials (mPCMs) to improve the thermal inertia of building walls, and accordingly respective energy savings. The research presented below consists of the exhaustive characterization of different AACs formulated from some waste generated during the proper management of municipal waste used as precursor. In this case study, AACs were formulated with the waste generated during the recycling of glass cullet, namely ceramic, stone, and porcelain (CSP), which is embedding a mPCM. The addition of mPCM was used as thermal energy storage (TES) material. The mechanical properties were also evaluated in order to test the feasibility of the use of the new formulated materials as a passive TES system. The results showed that the AAC obtained from CSP (precursors) mixed with mPCMs to obtain a thermal regulator material to be implemented in building walls was reached successfully. The material developed was resistant enough to perform as insulating panels. The formulated materials had high storage capacity depending on the PCM content. The durability of the mPCM shell was studied in contact with alkaline medium (NaOH 4 M) and no degradation was confirmed. Moreover, the higher the content of mPCM, the lower the mechanical properties expected, due to the porosity increments with mPCM incorporation in the formulations.
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Ovsyannikov, V. E., G. N. Shpitko, R. Yu Nekrasov, and D. E. Vas'kov. "Increase of strength of cast-iron cylinder liners of engines of road construction vehicles." Izvestia MGTU MAMI 1, no. 3 (2020): 36–40. http://dx.doi.org/10.31992/2074-0530-2020-45-3-36-40.
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Cylinder liners made of gray cast iron are quite widespread in the design of engines of road con-struction vehicles. The negative properties of this structural material include relatively low strength and high fragility. This increases the probability of both manufacturing and operational defects. Therefore, improving the performance of the considered parts is an urgent problem. A promising direction in this case is the use of chemical-and-thermal treatment. The aim of the work is to study the effect of chemical-and-thermal treatment of gray cast iron on strength. The paper investigates the strength of cast iron subjected to chemical-and-thermal treatment (thermal diffusion surface al-loying). On the basis of experimental studies, the effect of the thickness of the hardened layer on the strength was studied. A numerical model is created in the Ansys software. The effect of the hardened layer on the strength of cylinder liners of engines of road-building vehicles is investigated.
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Motaung, Tshwafo E., and Mokgaotsa J. Mochane. "Systematic review on recent studies on sugar cane bagasse and bagasse cellulose polymer composites." Journal of Thermoplastic Composite Materials 31, no. 10 (November 28, 2017): 1416–32. http://dx.doi.org/10.1177/0892705717738292.
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Sugar cane bagasse (SCB) is one of the abundant and available natural fibres in many countries as a by-product from sugar cane mills after an extraction of sugar. Attempts have been made to convert this by-product into useful eco-friendly cement-bonded composites and polymer composites, which can be used for various internal and external applications in buildings. Some researchers extracted cellulose from SCB and incorporated it in different polymeric matrices. The investigations included optimization of parameters and chemical treatments such as bagasse content or coupling agents for a production of effective composites. The influence of different parameters on the setting of the composite material such as botanical components of the fibre, thermal or chemical treatment of the fibre and bagasse fibre content have shown enhancement in properties. The recent work cited in this review suggests that SCB can be used to prepare fibre-reinforced polymer composites for commercial use. Furthermore, there seems to be a little research done on the application of SCB nanocellulose–polymer composites. In fact, this review discusses the current state of SCB as filler in polymer composites with citation of the latest research. It furthermore exposes more research options for SCB and its ash.
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Rosato, Antonio, Antonio Ciervo, Renata Concetta Vigliotti, Roxana Adina Toma, Rossana Pellegrino, Giovanni Ciampi, Michelangelo Scorpio, and Sergio Sibilio. "Influence of Climatic Conditions on Dynamic Performance of Solar Hybrid Heating and Cooling Systems Integrating Seasonal Borehole Thermal Energy Storages: Application to School Buildings in the Campania Region of Italy." Tecnica Italiana-Italian Journal of Engineering Science 65, no. 2-4 (July 30, 2021): 187–95. http://dx.doi.org/10.18280/ti-ijes.652-407.
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In this paper 5 different case studies of solar hybrid heating and cooling networks serving 5 different school buildings assumed as representative of the 5 provinces of the Campania region (southern Italy) have been modelled, dynamically simulated and analyzed by means of the software TRNSYS over a 5-year period. The plants are based on the operation of solar thermal collectors coupled with a seasonal borehole thermal energy storage; the solar field is also integrated with photovoltaic panels coupled with an electric energy storage; a solar-powered adsorption system is used for covering the cooling requirements. Specific weather data files have been developed for each city based on 1-year in-situ hourly measurements to accurately take into account the influence of climatic conditions on systems’ performance; the effects of thermo-physical properties of underground associated to the different locations have also been taken into consideration according to measured data available in the literature. The proposed systems have been compared with conventional Italian heating and cooling plants from energy, environmental and economic points of view in order to assess the potential benefits, highlight the effects of both weather data and characteristics of underground as well as promote the diffusion of solar systems for Italian applications.
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Khadzhishalapov, G. N., Abdulla M. Hajiyev, T. A. Khezhev, and Shakhmurad A. Alimuradov. "Heat Resistant Light Solutions on the Activated Composite Binder from the Local Mineral Raw Materials." Materials Science Forum 974 (December 2019): 400–405. http://dx.doi.org/10.4028/www.scientific.net/msf.974.400.
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One of the heat-resistant solutions effective application areas is to protect the structures from the high temperatures’ effects in case of fire. Material damage from fires amounts to hundreds millions of rubles. An effective way to improve the fire resistance of the building structures is to apply heat-insulating coatings to the surface. One of the compositions to protect the structures from high temperatures is a heat-resistant solution based on the expanded clay sand and perlite. The effectiveness of the solutions application to protect against high temperatures exposure increases due to the fact that these solutions perform both thermal and decorative functions. In the field of conventional building structures protection from the high temperatures effects, the extensive studies have been carried out by such scientists such as [6,7,8,9,32,10], and the solutions that simultaneously perform the decorative functions and the functions of protection against the effects of high temperatures in the event of fire have been little studied except for the usual restoration solutions. The study of the solutions’ special properties for the protection of small architectural structures such as fire resistance, thermal conductivity and linear thermal expansion coefficient is a rather important task.
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Elorza, Edurne, Ibon Aranberri, Xiangming Zhou, Gediminas Kastiukas, and Juan Antonio Alduncin. "Sustainable insulating foams based on recycled polyurethanes from construction and demolition wastes." Open Research Europe 1 (April 19, 2021): 37. http://dx.doi.org/10.12688/openreseurope.13288.1.
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Background: Polyurethane (PU) foams contained in construction and demolition wastes (CDW) represent a great environmental impact, since they usually end in landfill or incineration processes. The goal of this work is to develop a way to formulate PU foams, maintaining (or ever improving) their performance, by the re-use of those industrial wastes. This procedure will allow minimize both the volume of disposal to be treated by other ways and the amount of pristine raw material needed to produce new PU foams. Methods: In this work, new rigid and soft polyurethane (PU) foams have been formulated with addition of recycled PU foams coming from demolition of buildings. Density, Fourier transform infrared analysis, compression properties and thermal conductivity were measured to characterize the resulting foams. Results: The work showed that addition of filler coming from recycled PU foams should be limited to low percentages, in order to allow good foam evolution from the reactants. Thermal conductivity values of modified rigid foams are worse than those of pristine foam, which is undesirable for thermal insulation purposes; however, in the case of soft foams, this parameter improved to some extent with low levels of recycled PU foam addition. Conclusions: The studied procedure could contribute to reduce the thermal conductivity of pristine soft PU foam, which would be of interest for applications where thermal insulation matters.
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Attarian, Koorosh, and Behnaz Safar Ali Najar. "Vernacular and historic underground urban facilities and sustainability of cities case study." Journal of Cultural Heritage Management and Sustainable Development 9, no. 1 (February 4, 2019): 2–23. http://dx.doi.org/10.1108/jchmsd-06-2017-0030.
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Purpose The purpose of this paper is to investigate the underground levels of a city to explore how vernacular and historic underground urban facilities help traditional cities to be sustainable. Therefore, the authors look at how culture, climate and economy affect those facilities. Design/methodology/approach The paper focuses on vernacular and local underground urban facilities in historic cities to find more sustainable processes of urban development that integrate cultural, climatic and economical concerns into design planning. The paper is based on a case study of the underground infrastructure of Dezful, Iran. Findings There are several vernacular building styles around the world, especially in Iran, with different shapes, materials, arrangements and concepts. Building construction has significant impacts on the environment and natural resources. Dezful is a city in Iran with a lot of potential in terms of its architecture. Vernacular cities possess infrastructure that helped them thrive in harsh climates. For instance, Dezful takes advantage of a systematic infrastructure termed the “Underground City.” Originality/value The traditional architecture of Dezful plays an important role in creating underground spaces, especially urban and architectural elements with thermal isolation properties that can be used as housing and as food storage. In this century, building construction could adopt these environmental properties, which could lead to low energy consumption in urban environments. Considering traditional and contextual elements in urban planning and design could revive sustainable community practices in urban environments.
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Fomina, Natalya, Olga Fedotova, and Mikhail Polyanskiy. "Changes in the composition and structure at PET-waste processing into building materials." MATEC Web of Conferences 251 (2018): 01002. http://dx.doi.org/10.1051/matecconf/201825101002.
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The results of studies of the composition and structure of polyethylene terephthalate in the process of thermomechanical processing of polymeric wastes as well as properties of waste products obtained on the basis of waste are presented. Methods of infrared spectroscopy, differential thermal analysis and thermogravimetry, as well as standard methods for manufacturing and testing the technical properties of samples of structural building products were used. As a result of thermomechanical processes during re-melting of polyethylene terephthalate waste, the number of hydroxyl groups in the polymer composition decreases, due to the possible cross-linking and polycondensation of macromolecules through terminal hydroxyl and unactivated carboxyl groups. In this case, conformational rearrangements take place in the structure of polyethylene terephthalate. When thermomechanical processing of secondary PET with rapid cooling of the melt, the temperature of the onset of subsequent melting decreases, which allows to reduce power consumption in melting-mixing units during the process of manufacturing construction products. Construction and technical properties of secondary PET as binder composite building materials allow to obtain potentially durable products with structural strength and high decorative.
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Diachok, Oksana, Larysa Shuldan, and Alina Yanbukhtina. "FEATURES AND COMPREHENSIVE STUDY OF SACRED BUILDINGS OF THE END OF 20 – EARLY 21 CENTURY (ON THE EXAMPLE OF THE CHURCH OF ST. PETER IN TERNOPIL)." Urban development and spatial planning, no. 77 (May 24, 2021): 181–95. http://dx.doi.org/10.32347/2076-815x.2021.77.181-195.
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The article examines some problems of temples of the late 20th - early 21st centuries, in which modern architectural ideas, modern design components appeared together with new design solutions. The study uses a set of general scientific (empirical and theoretical) and special research methods (method of visual and instrumental surveys, historical and comparative analysis, art analysis, method of thermal monitoring and calculation). A comprehensive study was conducted on the example of St. Peter's Church in Ternopil (architect Serhiy Hora, designer Józef Simels). It is established that its modern stylistic image, modern formative components are combined with the traditional plan, which has historically developed in church construction. The facilitation of the main load-bearing structures was made possible by the use of exceptional metal curved trusses and a reinforced concrete belt. A comprehensive analysis of the condition of the church building revealed a number of problems typical for churches of this period of construction: the progressive spread of efflorescence, mycological damage to the plaster, premature destruction of building materials and destruction of structures; loss of insulative properties of structures and increase in energy consumption, deterioration of acoustic characteristics in the church space, loss of uniformity of sound distribution over its area. The dependence of these problems on changes in temperature and humidity in the temple building has been established. According to the results of instrumental research, a correlation analysis was performed to assess the degree of relationship between the distribution of moisture and temperature with the peculiarities of operation, the nature of operation and the level of thermal insulation of enclosing structures. The consequences of further moistening of the inner surfaces of the fences have been established: consequences for the interior; microclimatic (hygienic) consequence; constructive consequences; effects on energy consumption and acoustic effects. As a result of the calculations, recommendations for troubleshooting were provided. Using in this context a systematic interpretation of case studies, the study of actions that would help increase the level of comfort in churches and their preservation, the authors propose a reconstruction with an assessment of the quality of intervention at each stage.
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Aparicio-Ruiz, Pablo, José Guadix-Martín, Elena Barbadilla-Martín, and Jesús Muñuzuri-Sanz. "Applying Renewable Energy Technologies in an Integrated Optimization Method for Residential Building’s Design." Applied Sciences 9, no. 3 (January 29, 2019): 453. http://dx.doi.org/10.3390/app9030453.
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Designing a Zero Energy Building (ZEB) requires an optimal choice of the materials of a building envelope. Different material properties and window areas could be selected to generate a set of possibilities of the design of a building, being the demand defined by its thermal characteristics. The energy demand of a building could be produced with renewable systems such as photovoltaic. Moreover, the HVAC (Heating, Ventilation, and Air Conditioning) systems could be selected considering the system cost. The present methodology focuses on finding a balance between investment and low energy consumption for a building, based on an integrated optimization method. Such methodology applies a Tabu search algorithm and a simplified model to select the passive design. Afterwards, active elements of the design, as photovoltaic systems, are selected. Therefore, the methodology faces the problem of estimating the annual energy demand and the life cycle cost. The goal is the design of a building with a large amount of energy generated by renewable energy, to have a ZEB, and in the worst case, a nearly Zero Energy Building (nZEB). This methodology reduces investment, reduces the energy demand and selects the best construction materials, renewable energy, and air conditioning system. The present paper analyzes a set of case studies considering different climatic zones in Spain. The results conclude that the methodology could help builders in the design stage, to find a new design that allows a ZEB with the optimal life cycle cost.
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Hens, Hugo S. L. C. "Thermal comfort in office buildings: Two case studies commented." Building and Environment 44, no. 7 (July 2009): 1399–408. http://dx.doi.org/10.1016/j.buildenv.2008.07.020.
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SAVVIN, D. V., L. L. FEDOROVA, and E. E. SOLOVIEV. "EXPERIENCE OF GPR INVESTIGATION AT ENGINEERING-GEOLOGICAL SURVEY IN CENTRAL YAKUTIA." Engineering survey 12, no. 7-8 (November 20, 2018): 92–100. http://dx.doi.org/10.25296/1997-8650-2018-12-7-8-92-100.
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Тhe territory of the Republic of Sakha (Yakutia) is located in the north-eastern part of the Eurasian continent, the Republic is the largest region of the Russian Federation. One of the features of the region is the presence of permafrost. The construction and exploitation of engineering structures is conducted in a harsh climate and difficult engineering-geocryological conditions on this territory. In this case, the disturbance of thermal equilibrium of permafrost, is accompanied by subsidence, deformation of the buildings foundation and structures, and sometimes to their partial destruction. The article presents the results of GPR studies for engineering-geological surveys in Central Yakutia are presented. The relevant research focused on the improvement of assessment of informativeness, efficiency and authenticity of ground condition according to the indications of remote geophysical methods, in particular GPR, is being examined. The results of studies aimed at studying the characteristic features of GPR wave fields for the development of signs of the interpretation of cryogenic processes and phenomena in the soils of the foundations of engineering structures according to GPR data are presented. The wave fields characteristics and GPR signs of talik, water-bearing zones, areas of weakening of the soil, increase the capacity of the active layer caused by the thawing of permafrost, infiltration of the supra permafrost water boundaries identification have been developed and are determined . The selection of interpretative features of permafrost processes at the research site was carried out by comparing the results of GPR with drilling data and analysis of the wave pattern, which considered the configuration, intensity, length of the in-phase axes. The good reproducibility of GPR investigation with the data of electrical resistivity tomography (electrical sounding, multipole sounding) is shown. The effectiveness of GPR in identifying zones, associated with the development of negative cryogenic processes, recommended for drilling for determination of physical and mechanical properties of soils, for example, complicated permafrost conditions of Yakutia.
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Koňáková, Dana, Monika Čáchová, Eva Vejmelková, Martin Keppert, and Robert Černý. "Thermal Properties of Selected Timbers." Advanced Materials Research 982 (July 2014): 100–103. http://dx.doi.org/10.4028/www.scientific.net/amr.982.100.
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This article deals with thermal properties of selected kinds of timber. Wood, generally, is one of often used natural materials in building structures. For our research, woods were selected according to frequency of utilization in civil engineering branch. Four different timbers were chosen, and experimental determinations of their properties were performed. Basic physical properties as well as thermal properties belong among studied characteristics. From achieved results, it is obvious, that the bulk density of studied wood ranges between 373 kg m-3 and 649 kg m-3, the open porosity differ by 13%. Regarding thermal properties, values of the thermal conductivity as well as the specific heat capacity are influenced mainly by the open porosity and moisture content. The thermal conductivity in dry state varies by about 31% while in the case of the specific heat capacity the difference is about 19%. Obtained date will be used in the mathematical analysis of heat transport in building structures.
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Kozlov, Sergey, Boris Efimov, Ekaterina Bobrova, Ekaterina Zinovieva, and Ekaterina Zhukova. "Optimization of foamed plastic technology." E3S Web of Conferences 97 (2019): 06010. http://dx.doi.org/10.1051/e3sconf/20199706010.
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Insulation systems of building structures involve the solution of the following group of tasks: creation of favorable conditions for the work of structural elements and construction as a whole; optimization of heat losses through the insulation shell; creation of comfortable conditions in the room. Such a system would function normally if effective thermal insulation, including polyethylene, were used. The price of polyethylene foam can be reduced without prejudice to the properties in the case of the use of secondary polyethylene foam. The article presents the results of experimental studies, the purpose of which is to optimize the composition of polyethylene foam with the addition of secondary polyethylene, the formation of methods of selection of its composition and the development of systems for the application of products based on polyethylene foam. The article presents the main provisions of the method of analytical optimization, which allows to significantly reducing the material and time costs of processing the results of the experiment. The article deals with aspects of the implementation of construction systems using products based on polyethylene foam in terms of minimizing heat loss through the contact areas. Mandatory criteria for the construction and implementation of insulation systems are safety conditions, including both structural safety (including maintenance-free cycle) and fire safety.
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Ganobjak, Michal, Samuel Brunner, and Jannis Wernery. "Aerogel materials for heritage buildings: Materials, properties and case studies." Journal of Cultural Heritage 42 (March 2020): 81–98. http://dx.doi.org/10.1016/j.culher.2019.09.007.
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Jovanovic-Popovic, Milica, Ana Radivojevic, Dusan Ignjatovic, and Martin Elezovic. "Attic extension and thermal renovation of the residential building: Case study." Spatium, no. 13-14 (2006): 41–46. http://dx.doi.org/10.2298/spat0614041j.
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Buildings are the only resource growing constantly. Although relevant data for Serbia is not available, it is presumed that even more than 50% of energy production is spent on buildings in our country. This conclusion is based on two facts: the present industrial production and the state of buildings. In order to establish measures for energy efficient refurbishment, one residential building was analyzed in Belgrade. The chosen building represents the construction period when application of thermal insulation was not obligatory according to building regulation. As more than 35% of buildings were built in that period, they represent great potential for energy savings through the process of refurbishment.
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Basu, Dhiman, and Harshit Nema. "Natural properties of confined masonry buildings - experimental case studies and possible inferences." International Journal of Masonry Research and Innovation 4, no. 3 (2019): 197. http://dx.doi.org/10.1504/ijmri.2019.10019399.
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Nema, Harshit, and Dhiman Basu. "Natural properties of confined masonry buildings - experimental case studies and possible inferences." International Journal of Masonry Research and Innovation 4, no. 3 (2019): 197. http://dx.doi.org/10.1504/ijmri.2019.100567.
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Cai, Lei, Hanna Lee, Kjetil Schanke Aas, and Sebastian Westermann. "Projecting circum-Arctic excess-ground-ice melt with a sub-grid representation in the Community Land Model." Cryosphere 14, no. 12 (December 18, 2020): 4611–26. http://dx.doi.org/10.5194/tc-14-4611-2020.
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Abstract. To address the long-standing underrepresentation of the influences of highly variable ground ice content on the trajectory of permafrost conditions simulated in Earth system models under a warming climate, we implement a sub-grid representation of excess ground ice within permafrost soils using the latest version of the Community Land Model (CLM5). Based on the original CLM5 tiling hierarchy, we duplicate the natural vegetated land unit by building extra tiles for up to three cryostratigraphies with different amounts of excess ice for each grid cell. For the same total amount of excess ice, introducing sub-grid variability in excess-ice contents leads to different excess-ice melting rates at the grid level. In addition, there are impacts on permafrost thermal properties and local hydrology with sub-grid representation. We evaluate this new development with single-point simulations at the Lena River delta, Siberia, where three sub-regions with distinctively different excess-ice conditions are observed. A triple-land-unit case accounting for this spatial variability conforms well to previous model studies for the Lena River delta and displays markedly different dynamics of future excess-ice thaw compared to a single-land-unit case initialized with average excess-ice contents. For global simulations, we prescribed a tiling scheme combined with our sub-grid representation to the global permafrost region using presently available circum-Arctic ground ice data. The sub-grid-scale excess ice produces significant melting of excess ice under a warming climate and enhances the representation of sub-grid variability of surface subsidence on a global scale. Our model development makes it possible to portray more details on the permafrost degradation trajectory depending on the sub-grid soil thermal regime and excess-ice melting, which also shows a strong indication that accounting for excess ice is a prerequisite of a reasonable projection of permafrost thaw. The modeled permafrost degradation with sub-grid excess ice follows the pathway that continuous permafrost transforms into discontinuous permafrost before it disappears, including surface subsidence and talik formation, which are highly permafrost-relevant landscape changes excluded from most land models. Our development of sub-grid representation of excess ice demonstrates a way forward to improve the realism of excess-ice melt in global land models, but further developments require substantially improved global observational datasets on both the horizontal and vertical distributions of excess ground ice.
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Filonenko, Olena, Oleg Yurin, and Olga Kodak. "Thermal Modernization of the Panel Buildings External Walls." International Journal of Engineering & Technology 7, no. 3.2 (June 20, 2018): 116. http://dx.doi.org/10.14419/ijet.v7i3.2.14386.
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The thermal protection level of the first mass series panel buildings (series 111-94) is the lowest among residential buildings in Poltava. The problems of these buildings’ thermal modernization, is consideration of heat-conducting inclusions effect on the reduced resistance to heat transfer. In the studies such heat-conducting inclusions as the panel joints’ design, the window slope and the external wall geometry (the external corner) were taken into account. Studies were performed for the four pattern sections of the outer wall. Panels of two thickness variants with two joint designs were under consideration.To analyze the thermal protection level, the results of the two-dimensional temperature fields’ calculations were used. The analysis of the wall panels’ thermal protection level before the thermal modernization was performed. The magnitude of the heat conducting inclusions effect on reduced resistance of the walling to the heat transfer before and after the thermal modernization is determined. Possible ways of improving the wall panels’ heat-protective properties to the level of the standards in Ukraine are considered. The optimal variant of insulation for each pattern was chosen.
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Atynian, Armen, Kateryna Bukhanova, Roman Tkachenko, Volodymyr Manuilenko, and Dmytro Borodin. "Energy Efficient Building Materials with Vermiculite Filler." International Journal of Engineering Research in Africa 43 (June 2019): 20–24. http://dx.doi.org/10.4028/www.scientific.net/jera.43.20.
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The possibility of obtaining the vermiculite fire treatment at low temperature (burnt vermiculite) is considered in the article. The vermiculite structure features are investigated to reduce the subsequent burn temperature. By X-ray diffraction analysis it is established that the pre-treatment by a salt solution causes a change in the elementary cell of the vermiculite crystalline grid. It allows to receive the extended vermiculite under the lower burn temperature than in case of the ordinary non-treated vermiculite. To show the creation possibility of the building materials with burnt vermiculite the concrete unit weight and strength with gypsum and cement binder are studied. It is determined that the mentioned concrete strength is higher compared to concrete with ordinary vermiculite at the same density of these concretes. The thermal insulation properties are also significantly higher. The light concrete with vermiculite aggregate is used as the thermal-shield enclosing structures in building and structure constructions. The decrease of the vermiculite burn temperature will contribute to reducing the energy intensity of construction as a whole.
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Qahtan, Abdultawab, Nila Keumala, S. P. Rao, and Ali Mohammed Alashwal. "A Case Study to Assess the near-Glazed Workplace Thermal Performance." Advanced Materials Research 374-377 (October 2011): 1724–32. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.1724.
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Passive solar control solutions have been widely used in buildings in tropic countries like Malaysia. It is assumed that these solutions may notably control the heat-gain of buildings. However, there is a lack of empirical studies that assess the extent of green-glazed techniques to sufficiently control solar heat-gain. The current study uses a case study approach to examine the thermal indoor performance, particularly the near-glazed workplace area. The performance of the ST Diamond Building (in Putra Jaya, Malaysia) has been examined in terms of: outdoor/indoor dry bulb temperature; glass surface temperature; heat flux through glazing; outdoor/indoor air movement; lux and; solar radiation. The results of the field analysis indicated that ST Diamond Building’s green-glazed solutions are efficient to control solar heat gain, which in turn will lead to reduce energy consumption for controlling solar heat loads.
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Katunská, Jana, Dušan Katunský, and Veronika Labovská. "Selected problems of thermal insulation of historical buildings." Selected Scientific Papers - Journal of Civil Engineering 14, no. 1 (December 1, 2019): 67–74. http://dx.doi.org/10.1515/sspjce-2019-0007.
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Abstract There are problems with historical buildings when changing the thermal insulation properties of buildings. The Energy Efficiency Act exempted historic buildings from certification. Not all old, historic buildings have monument protection. It is necessary to take into account the above mentioned facts in case of renovation and reconstruction of an old building. Otherwise, a normal building is approached and a building of historical value is treated differently. Methods hidden insulation, which preserves the authenticity of cultural monuments and real estate in the heritage areas, is a current challenge of heritage practice. The sustainability of the operation of historic buildings ultimately means the preservation and appropriate use of the heritage fund. Fortunately, the list of such interventions that do not jeopardize the monumental values or the use of the building is gradually increasing. This is mainly due to modern, increasingly sophisticated materials and technologies. In this paper we offer a basic overview of the most frequently used and practice-tested interventions in historical buildings, but we focus on details.
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Agliata, Rosa, Alfonso Marino, Luigi Mollo, and Paolo Pariso. "Historic Building Energy Audit and Retrofit Simulation with Hemp-Lime Plaster—A Case Study." Sustainability 12, no. 11 (June 5, 2020): 4620. http://dx.doi.org/10.3390/su12114620.
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Hemp-lime composite is a natural material, which is being increasingly used and studied in the construction sector, thanks to its recyclability, hygrothermal comfort and healthiness features. The aim of this paper is to test the benefits in terms of energy efficiency achieved through the use of hemp-lime composite as insulation in a possible refurbishment intervention. With the aim of extending the knowledge about the benefits achieved through from the integration of this natural material into construction production process, a real building in south of Italy was selected and a substitution of the standard gypsum-lime plaster with a hemp-lime one was simulated by means of a specific software (Termus® by Acca Sotware, Bagnoli Irpino, Italy), serving for the assessment of the energy performance. Case study analysis highlighted the good thermal insulation properties of hemp-based plaster, allowing thermal dispersion to decrease in the winter season and improve the summer performance of the walls by approximately 20% compared to traditional plaster. This results in a one-level improvement of the building in energy classification according to Italian regulation.
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Miani, Marco, Caterina Di Marco, Giada Frappa, and Margherita Pauletta. "Effects of Dissipative Systems on the Seismic Behavior of Irregular Buildings—Two Case Studies." Buildings 10, no. 11 (November 7, 2020): 202. http://dx.doi.org/10.3390/buildings10110202.
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Conservation of heritage buildings has become a very important issue in many countries, as it is in Italy, where a great number of existing buildings of historical–artistic importance are seismically vulnerable. To improve existing building behavior, researchers focus on the design of retrofit interventions. This paper presents the application of energy dissipation devices in the retrofit of two existing Reinforced Concrete (RC) buildings, both irregular in plan and along their heights, designed for gravitational loads only. These buildings are representative of Italian public housing built in the 1960s and early 1970s. Technical information and mechanical properties of materials are presented, and non-linear analyses are carried out to evaluate the buildings’ behavior under earthquake loads. Many of their structural members do not satisfy the verifications required by the Italian Building Code. Retrofit interventions with buckling-restrained axial dampers in one building and viscous fluid dampers in the other are proposed. The verifications of the retrofitted buildings and the amount of the energy absorbed by the devices with respect to that absorbed by the unretrofitted buildings show the effectiveness of the proposed interventions. Moreover, it is demonstrated that adequate dispositions of the dissipative devices in plan and along the height increase the torsional stiffness of the buildings, improving their structural response under seismic action.
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Felius, Laurina C., Mohamed Hamdy, Fredrik Dessen, and Bozena Dorota Hrynyszyn. "Upgrading the Smartness of Retrofitting Packages towards Energy-Efficient Residential Buildings in Cold Climate Countries: Two Case Studies." Buildings 10, no. 11 (November 3, 2020): 200. http://dx.doi.org/10.3390/buildings10110200.
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Improving the energy efficiency of existing buildings by implementing building automation control strategies (BACS) besides building envelope and energy system retrofitting has been recommended by the Energy Performance of Buildings Directive (EPBD) 2018. This paper investigated this recommendation by conducting a simulation-based optimization to explore cost-effective retrofitting combinations of building envelope, energy systems and BACS measures in-line with automation standard EN 15232. Two cases (i.e., a typical single-family house and apartment block) were modeled and simulated using IDA Indoor Climate and Energy (IDA-ICE). The built-in optimization tool, GenOpt, was used to minimize energy consumption as the single objective function. The associated difference in life cycle cost, compared to the reference design, was calculated for each optimization iteration. Thermal comfort of the optimized solutions was assessed to verify the thermal comfort acceptability. Installing an air source heat pump had a greater energy-saving potential than reducing heat losses through the building envelope. Implementing BACS achieved cost-effective energy savings up to 24%. Energy savings up to 57% were estimated when BACS was combined with the other retrofitting measures. Particularly for compact buildings, where the potential of reducing heat losses through the envelope is limited, the impact of BACS increased. BACS also improved the thermal comfort.
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Derakhshan, H., Phillip Visintin, and M. C. Griffith. "Case studies of material properties of late nineteenth-century unreinforced masonry buildings in Adelaide." Australian Journal of Civil Engineering 15, no. 2 (July 3, 2017): 109–16. http://dx.doi.org/10.1080/14488353.2017.1401196.
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Li, Wei, Zhen Huang, Xiao Chu Wang, and Jun Wei Wang. "Review of Crumb Rubber Concrete." Applied Mechanics and Materials 672-674 (October 2014): 1833–37. http://dx.doi.org/10.4028/www.scientific.net/amm.672-674.1833.
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Rubber concrete acted as one kinds of building materials came from the traditional modification concrete, and it had the excellent thermal insulation properties, such as light, good toughness, good thermal insulation, so it had been initially used in civil engineering, such as railways, highways and so it’s like. It improved the large rigidity and insufficient toughness for the ordinary high strength concrete, and also offered a better choice for the treatment of waste rubber. This paper combined the rubber research institute of concrete for at home and abroad about 30 years, and summed up the way of modification, the mechanical properties, application status, and indicated the existing problems about the studies concrete to the rubber concrete.
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Drozdzol, Krzysztof. "Thermal and Mechanical Studies of Perlite Concrete Casing for Chimneys in Residential Buildings." Materials 14, no. 8 (April 16, 2021): 2011. http://dx.doi.org/10.3390/ma14082011.
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Chimneys are structures designed to convey exhaust gases from heating devices to the outside of buildings. The materials from which they are made have a great impact on their fire safety, as well as on the safety of the whole building. As current trends in the construction industry are moving towards improving the environmental impact and fire safety, changes to building materials are constantly being introduced. This also applies to the development of chimney technology, as there is still a recognised need for new solutions when it comes to materials used in the production of chimney systems. This article presents the findings of tests carried out on a chimney made from innovative perlite concrete blocks. Four different perlite concrete blocks that differed in bulk densities were analysed. The obtained results were then compared with widely used leca (lightweight expanded clay aggregate) concrete blocks. The test results confirmed high insulation properties of the perlite concrete block, from which the innovative chimney casing was made. The fire safety level was maintained even in high temperatures that occur during soot fire (1000 °C). These properties were retained despite there being no additional insulation of the flue duct. Even though the thermal load decreased the compressive strength of the chimney blocks, they still displayed sufficient average strength of 4.03 MPa. Additionally, the test results confirmed the possibility of recovering heat from the chimney with the efficiency of 23–30%, which constitutes a considerable increase compared to chimneys made from leca concrete blocks.
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Esposti, Walter. "The Final Thermal Inspection of Buildings by Means of Short Period Performance Monitoring: Two Case Studies." Journal of Thermal Insulation 11, no. 4 (April 1988): 279–95. http://dx.doi.org/10.1177/109719638801100408.
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Azarnejad, Araz, and Ardeshir Mahdavi. "Implications of façades’ visual reflectance for buildings’ thermal performance." Journal of Building Physics 42, no. 2 (October 4, 2017): 125–41. http://dx.doi.org/10.1177/1744259117731287.
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The surface properties of building façades have implications for thermal performance of buildings and might also influence outdoor thermal comfort conditions for pedestrians. A surface property, which is frequently used by building engineers and specially architects, is the visual reflectance. In this article, effects of façades’ visual reflectance on thermal aspects of building performance have been investigated in two parts. In the first part, the result of a field study is presented. The study explores the relationship between the visual reflectance of actual building façades and the corresponding surface temperatures. A number of buildings with diverse façade colors were selected. Surface temperatures were measured via infrared thermography. Façades’ visual reflectance was derived via simultaneous measurement of the illuminance on the façades and their luminance. Furthermore, incident solar radiation, ambient air temperature, and relative humidity were measured. The results of the field study display a non-random relationship between the building façades’ visual reflectance and their surface temperatures. The second part of the research involved the deployment of a calibrated simulation tool toward exploring the impact of façades’ visual reflectance on thermal performance of buildings. The results suggest that the magnitude of visual reflectance has little impact on indoor temperature and heating demand in case of façades with external insulation layer but may influence cooling loads in case of non-insulated buildings.
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Gołdyn, Michał, and Tadeusz Urban. "Failures of the Cast-Iron Columns of Historic Buildings—Case Studies." Infrastructures 5, no. 9 (September 2, 2020): 71. http://dx.doi.org/10.3390/infrastructures5090071.
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Selected technical problems related to the rehabilitation of cast-iron columns in structures from the turn of the 19th and 20th century are discussed in the paper. Lack of contemporary standard regulations related to the design of cast-iron structures is a significant problem in the design works and experimental investigations on cast-iron columns are frequently required. The paper presents results of the tests concerning principal properties of cast-iron—strength and deformability. The historical design principles are discussed in the light of the results of experimental investigations. As it was demonstrated, the actual load-carrying capacities of cast-iron columns may exceed by several times the values resulting from the 20th century design rules. The conservatism of the design principles resulted, however, from the material uncertainties—lack of homogeneity and hidden defects of the cast-iron. Selected examples of failures of cast-iron columns from 19th-century structures such as post-industrial buildings and engineering structures are discussed. They resulted from errors made during adaptation works. The reasons for these failures and considered methods of repairing the structures are presented.
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Buday, Peter, Rastislav Ingeli, and Miroslav Čekon. "Advanced Thermal Performance Analysis of Thermal Break Element Applied in Balcony Slab." Advanced Materials Research 1041 (October 2014): 167–70. http://dx.doi.org/10.4028/www.scientific.net/amr.1041.167.
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Thermal performance of any building component is the result not only of its thermophysical properties but also of a way of final installation and connections altogether of their all elements. In addition, thermal leakage and bridging in buildings can eventually contribute to a multitude of problems. The thermal bridge is the place in the building envelope through which heat transfer has a multi-dimensional nature. That is why in recent studies, the issue of heat transfer phenomena in the building components is considered as a multi-dimensional more frequently. One of the specific details that create thermal leakage is located in balcony slabs. This paper is focused on detailed analysis of thermal performance of thermal break element applied in balcony slab with relation to the thermal aspects of wall building envelope. Particular cases of commonly used balcony systems in buildings are observed related to multi-dimensional and parametric approach of modeling. As result of analyzed thermal aspects, such as importance of building envelope type and its thermal performance, variations of thermal properties, are presented as study findings that affected thermal bridges magnitude and resultant thermal performance of balcony slab detail.
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Tatsii, R., and O. Pazen. "DETERMINATION OF NON-STATIONARY TEMPERATURE FIELD IN THE SYSTEM OF TWO SPHERICAL SHELL." Bulletin of Lviv State University of Life Safety 19 (October 2, 2019): 79–86. http://dx.doi.org/10.32447/20784643.19.2019.08.
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The main classification indicator, in terms of fire safety, is the degree of fire resistance of the house. Depending on this indicator normalize its surface, the area of development and distance to other buildings and structures. The de-gree of fire resistance of the house is determined by the limit of fire resistance of its building structures and the limit of the fire spread by these structures. Therefore, the value of the fire resistance limit of building constructions, which con-sists of a house, significantly affect its architectural solution and the parameters of construction in general. On this ba-sis, taking into account the approaches to ensuring normalized fire resistance limits of the design and the features of their behavior under high-temperature (fire) influence is very relevant.Most research on building constructions. The proposed work is devoted to the application of the direct method to the study of heat transfer processes in the system of two embedded spherical bodies – a ball in a sphere. It is assumed that there is an ideal thermal contact between the balls, and the law of temperature change on the outer surface is an arbitrary function of time, and evenly distributed over the surface of the ball. Consequently, isotherms inside this construction are concentric fields, that is, the problem is symmetric and is solved for the first time in such a statement. To solve such a problem, in parallel, the auxil-iary problem of determining the distribution of a non-stationary temperature field in a two-layer hollow spherical structure with a "extracted" sphere of sufficiently small radius is raised. In this case the symmetry condition of the original problem is replaced by the condition of the second kind on the inner surface of this construction. The implementation of the solution of the auxiliary problem is carried out by applying a reduction method using the concept of quasiderivatives. In the future, the Fourier scheme is used with the use of the modified eigenfunctions method. To find the solution of the original problem, the idea of the boundary transition is used by passing the radius of the withdrawn bullet to zero. It is established that in this approach all the eigenfunctions of the corresponding problem on the eigenvalues have no singularities at zero, which means that the solutions of the original problem are constrained throughout the design. The solution of this problem at zero temperature on the outer surface coincides with those known in the literature. To illustrate the proposed method, a model example of finding the temperature field distribution in a system of two spherical bodies with different thermophysical properties of materials is solved. The results of the calcu-lations are presented in the form of a table and a three-dimensional graph of temperature change, depending on the time and spatial coordinates. The generalization of the results obtained in the event of any finite number of nested balls is a purely technical problem, and not a fundamental one. Note that while changing the boundary condition of the first kind to any other boundary condition (for example, the third kind) does not affect the scheme of solving similar tasks. Since the general scheme of studying the distribution of temperature fields in multi-layered structures with an arbitrary number of layers in the presence of internal sources of heat is studied in detail, the setting and solving of such problems for the system of nested balls does not cause any difficulty.
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Madhumathi, A., S. Radhakrishnan, and R. Shanthipriya. "Thermal Performance Evaluation of Green Roofs in Warm Humid Climates: A Case of Residential Buildings in Madurai, India." Key Engineering Materials 692 (May 2016): 82–93. http://dx.doi.org/10.4028/www.scientific.net/kem.692.82.
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Green roof application on real residential buildings in Tamilnadu, India is very limited and mostly concentrated in major cities mainly for visual purposes. There is not enough research has been conducted to boost up the benefits of green roof system in Warm and Humid weather in India. Green roofs have the potential to improve the thermal performance of a roofing system through shading, insulation, evapotranspiration and thermal mass, thus reducing a building’s energy demand for space conditioning. To quantify the thermal performance and energy efficiency of green roofs an experimental investigation was done in residential buildings of Madurai, Tamilnadu, India. This paper refers to the analysis of the thermal properties and indoor thermal performance study of the green roof. The investigation were implemented in two phases: during the first phase, extended surface, air temperature and relative humidity measurements were taken at the indoor and outdoor environment of the buildings where the green roof had installed and during the second phase of the study, the thermal properties of the green roof, as well as, the cooling potential were examined. Results showed vegetative roofs reduced heat gain compared to the white reflective roofs and conventional reinforced cement concrete due to the thermal mass, extra insulation, and evapo-transpiration associated with the vegetative roofing systems. The results also proved that green roofs provide acceptable indoor thermal performance with respect to the other conventional roofs while re-establishing the relationship between human and environment, which have been destroyed due to the rapid urbanization.
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Pisello, Anna Laura, and Federica Rosso. "Natural Materials for Thermal Insulation and Passive Cooling Application." Key Engineering Materials 666 (October 2015): 1–16. http://dx.doi.org/10.4028/www.scientific.net/kem.666.1.
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In this chapter a critical analysis about natural materials to enhance energy performance and thermal comfort in indoor and outdoor spaces is dealt with. In particular, thermal insulation and passive cooling application in buildings are analyzed. The physical properties permitting to achieve these benefits are presented, as well as the method and the international standards to measure them. Benefits deriving from these materials’ employment as insulation layers or buildings envelope in general of, or in the case of urban paving, are described and then the single materials are illustrated.Experimental and numerical data, as reported in the bibliography, support the dissertation with examples from the most recent research contributions.
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Zapata-Lancaster, Gabriela. "Thermal comfort practices in non-domestic buildings within the organisational context." Facilities 38, no. 1/2 (August 29, 2019): 114–31. http://dx.doi.org/10.1108/f-01-2019-0010.
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Purpose This paper aims to investigate the thermal comfort practices in four non-domestic buildings and explores how the organisational context affects the actions and practices of occupants and facilities managers. Design/methodology/approach The study applied qualitative methods and post-occupancy evaluation methodologies to investigate the thermal practices in four case studies. A combination of qualitative and quantitative methodologies was deployed, namely, semi-structured interviews, questionnaires, observation and monitoring studies of building performance. Findings The concept “distributed agency” was applied to analyse the thermal comfort practices in non-domestic buildings. This concept helped to illustrate everyday actions by occupants and facilities managers in relation to the organisational context. Occupants’ actions and building management practices could be affected by the organisation norms and context leading to problems and dissatisfaction with indoor thermal conditions. Research limitations/implications This study is based on a small number of case studies and it is exploratory. Extensive monitoring data were not available. However, the research identified the thermal conditions and occupants’ satisfaction levels as background where actions to achieve thermal comfort and facilities manager’s practices took place. Practical implications The study suggests the need to examine in greater depth how the organisational goals and individual goals could be linked to support specific building performance targets. Social implications The paper advocates for the application of multidisciplinary approaches to study the occupant dimension of building performance. It suggests the need to develop a nuanced understanding of how occupants pursue comfort as active agents who interact with the built environment. Originality/value The study has applied social practice theory to consider the influence of the organisation on thermal comfort practices in non-domestic buildings; considering the perspectives of building occupants and facilities managements within the organisational context.
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Cascone, Stefano, Renata Rapisarda, and Dario Cascone. "Physical Properties of Straw Bales as a Construction Material: A Review." Sustainability 11, no. 12 (June 19, 2019): 3388. http://dx.doi.org/10.3390/su11123388.
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Straw bale buildings provide significant benefits in terms of costs, human health, and environmental sustainability. Several studies in different regions have underlined the remarkable properties of straw bales as insulating and construction material; however, to the authors’ knowledge, there are no reviews published on this topic. The main objective of this paper is to provide a better understanding of straw bale systems, focusing on durability and thermal and acoustic insulation properties. To this end, previous tests and studies on straw bale buildings around the world were reviewed, comparing their results, assessing where research currently stands, and identifying the aspects that need to be further investigated. Results from previous tests have highlighted their ability to achieve excellent living comfort and encouraged their use. Guidelines for the characteristics to be achieved during the baling process are now required. Combining straw bale walls with a render or any type of high-density layer can improve both the thermal and acoustic properties of straw bale constructions. Finally, a quantitative assessment of the most significant properties, such as thermal resistance and acoustic insulation, is necessary to reduce the gap between straw bales and traditional building materials.
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Yan, Zengfeng, Joseph C. Lam, and Jiaping Liu. "Experimental Studies on the Thermal and Moisture Properties of Rammed Earth Used in Adobe Buildings in China." Architectural Science Review 48, no. 1 (March 2005): 55–60. http://dx.doi.org/10.3763/asre.2005.4808.
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Tavukçuoğlu, Ayşe. "Non-Destructive Testing for Building Diagnostics and Monitoring: Experience Achieved with Case Studies." MATEC Web of Conferences 149 (2018): 01015. http://dx.doi.org/10.1051/matecconf/201814901015.
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Building inspection on site, in other words in-situ examinations of buildings is a troublesome work that necessitates the use of non-destructive investigation (NDT) techniques. One of the main concerns of non-destructive testing studies is to improve in-situ use of NDT techniques for diagnostic and monitoring studies. The quantitative infrared thermography (QIRT) and ultrasonic pulse velocity (UPV) measurements have distinct importance in that regard. The joint use of QIRT and ultrasonic testing allows in-situ evaluation and monitoring of historical structures and contemporary ones in relation to moisture, thermal, materials and structural failures while the buildings themselves remain intact. For instances, those methods are useful for detection of visible and invisible cracks, thermal bridges and damp zones in building materials, components and functional systems as well as for soundness assessment of materials and thermal performance assessment of building components. In addition, those methods are promising for moisture content analyses in materials and monitoring the success of conservation treatments or interventions in structures. The in-situ NDT studies for diagnostic purposes should start with the mapping of decay forms and scanning of building surfaces with infrared images. Quantitative analyses are shaped for data acquisition on site and at laboratory from representative sound and problem areas in structures or laboratory samples. Laboratory analyses are needed to support in-situ examinations and to establish the reference data for better interpretation of in situ data. Advances in laboratory tests using IRT and ultrasonic testing are guiding for in-situ materials investigations based on measurable parameters. The knowledge and experience on QIRT and ultrasonic testing are promising for the innovative studies on today’s materials technologies, building science and conservation/maintenance practices. Such studies demand a multi-disciplinary approach that leads to bring together knowledge on materials science and building science.
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Gullbrekken, Lars, Steinar Grynning, and Jørn Gaarder. "Thermal Performance of Insulated Constructions—Experimental Studies." Buildings 9, no. 2 (February 21, 2019): 49. http://dx.doi.org/10.3390/buildings9020049.
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Buildings that are designed to meet high-energy performance requirements, e.g., passive houses, require well-insulated building envelopes, with increased insulation thicknesses for roof, wall and floor structures. We investigate whether there are differences in the efficiency of thermal insulation materials at different moisture levels in the insulation and if there is a larger or smaller risk of natural convection in wood-fibre based insulation than in mineral wool. The work has mainly been performed by use of laboratory measurements included permeability properties and full-scale measurements of thermal transmittance of mineral wool and wood-fibre insulated constructions. In addition, calculations have been used to calculate resulting effects on the thermal performance of constructions. Results showed that the thermal conductivity was unaffected by moisture in the hygroscopic range. The air permeability was found to be approximately 50% higher for the wood-fibre insulation compared to mineral wool insulation. Measurements showed that the largest U-values and Nusselt numbers were found for the wall configuration. Calculation of the U-value of walls showed that in order to achieve the same U-value for the wood-fibre insulated wall as the mineral wool, it is necessary to add 20 mm insulation to the 250 mm wall and approximately 30 mm for the 400 mm wall.
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Calise, Francesco, Francesco L. Cappiello, Maria Vicidomini, Jian Song, Antonio M. Pantaleo, Suzan Abdelhady, Ahmed Shaban, and Christos N. Markides. "Energy and Economic Assessment of Energy Efficiency Options for Energy Districts: Case Studies in Italy and Egypt." Energies 14, no. 4 (February 16, 2021): 1012. http://dx.doi.org/10.3390/en14041012.
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In this research, a technoeconomic comparison of energy efficiency options for energy districts located in different climatic areas (Naples, Italy and Fayoum, Egypt) is presented. A dynamic simulation model based on TRNSYS is developed to evaluate the different energy efficiency options, which includes different buildings of conceived districts. The TRNSYS model is integrated with the plug-in Google SketchUp TRNSYS3d to estimate the thermal load of the buildings and the temporal variation. The model considers the unsteady state energy balance and includes all the features of the building’s envelope. For the considered climatic zones and for the different energy efficiency measures, primary energy savings, pay back periods and reduced CO2 emissions are evaluated. The proposed energy efficiency options include a district heating system for hot water supply, air-to-air conventional heat pumps for both cooling and space heating of the buildings and the integration of photovoltaic and solar thermal systems. The energy actions are compared to baseline scenarios, where the hot water and space heating demand is satisfied by conventional natural gas boilers, the cooling demand is met by conventional air-to-air vapor compression heat pumps and the electric energy demand is satisfied by the power grid. The simulation results provide valuable guidance for selecting the optimal designs and system configurations, as well as suggest guidelines to policymakers to define decarbonization targets in different scenarios. The scenario of Fayoum offers a savings of 67% in primary energy, but the associated payback period extends to 23 years due to the lower cost of energy in comparison to Naples.
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Krstic-Furundzic, Aleksandra, and Vesna Kosoric. "Improvement of energy performances of existing buildings by application of solar thermal systems." Spatium, no. 20 (2009): 19–22. http://dx.doi.org/10.2298/spat0920019k.
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Improvement of energy performances of the existing buildings in the suburban settlement Konjarnik in Belgrade, by the application of solar thermal systems is the topic presented in this paper. Hypothetical models of building improvements are created to allow the benefits of applying solar thermal collectors to residential buildings in Belgrade climate conditions to be estimated. This case study presents different design variants of solar thermal collectors integrated into a multifamily building envelope. The following aspects of solar thermal systems integration are analyzed in the paper: energy, architectural, ecological and economic. The results show that in Belgrade climatic conditions significant energy savings and reduction of CO2 emissions can be obtained with the application of solar thermal collectors.
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Grynning, Steinar, Alessandro Nocente, Lars Gullbrekken, and Kjell Skjeggerud. "Thermal mass and thermal comfort in offices – experimental studies of a concrete floor." MATEC Web of Conferences 282 (2019): 02087. http://dx.doi.org/10.1051/matecconf/201928202087.
Full textAbstract:
Previous studies demonstrated that the use of thermal mass in buildings can contribute to reduce the energy demand and improve the thermal comfort. The thermal mass effect strongly depends on the properties of the materials facing the internal environment. High thermal capacity and conductivity are vital to achieve the desired effects. Concrete have both and it is a common building material. However, scientifically sound experimental studies that quantify the effects in a controlled environment are scarce. The aim is to study the effects of thermal mass on indoor environment and comfort in a quantifiable way in an extensive experimental campaign where comparative measurements were carried out in The ZEB TestCell Laboratory in Trondheim, Norway. The facility consists of two identical real-weather exposed rooms the size of a single person office. One of the rooms was constructed with a 70 mm thick concrete flooring, the other with an 18 mm wood-flooring. Free-floating temperature propagations were measured in different natural ventilation scenarios. The results showed that peak temperatures were notably reduced in the test room with the concrete flooring. During the warmest periods, a temperature peak reduction of more than 10% was found compared to the wooden-floored room.