Download or read book Evaluating the Thermal Impacts of Different Masonry Wall Tie Designs Using FEM written by Yue Shao and published by . This book was released on 2021 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Building's space heating system accounts for more than half of the total building's energy consumption, reducing the energy use of space heating of buildings can decrease the national energy consumption of Canada and is helpful for sustainable development of the buildings. Improvement of thermal resistance of the wall is a reliable approach to decrease the energy consumption of the building. Masonry cavity walls is a commonly used type of exterior wall in Canada. It can provide reliable structural performance, considerable durability, and excellent thermal resistance. However, the presence of masonry ties, as a typical source of repeated thermal bridging, in the wall assembly significantly reduces the thermal resistance of the wall assembly. Ties are considered a typical source of repeated thermal bridging in masonry cavity wall assemblies. Thermal bridging can cause thermal resistance reduction due to its high conductivity material penetrating the thermal insulation layers. Ties thermal bridging effect provide additional heat transfer pathways in the wall assembly. Codes and industry catalogues require the thermal impact of thermal bridging to be considered when calculating the thermal resistance of exterior walls. Although a few studies have been conducted on the effect of ties in reducing the thermal performance of walls, the thermal impact of ties has not been comprehensively studied. Incomplete thermal bridging reduction effect evaluation will make insufficient HVAC system design and lead to energy consumption increase of the buildings. Also, the ties thermal impact on the thermal resistance of the ventilated air gap has not been determined. In this study, the effective thermal resistance of the ventilated air gap in masonry cavity walls considering ties thermal bridging impact was investigated, and the impact of ties on the thermal resistance of wall assemblies was addressed with different influence factors. Based on the parametric analysis, effective methods to reduce ties thermal bridging effect were suggested. The effective thermal resistance of the ventilated air gap in masonry cavity walls was studied by using coupling computational fluid dynamics (CFD) and steady-state thermal analysis in Finite element method (FEM) modelling. In addition, a parametric analysis of the impacts of ties on the effective thermal resistance of a unit wall area was performed by using FEM with variations in ties material, insulation R-values, tie depth, tie spacing, grouting in concrete masonry blocks, and the effect of adding insulation around the tie. Based on the results, the tie's thermal bridging effects and ventilation in the air gap affect the thermal resistance of the air gap. And according to the parametric analysis, the tie material is the most influential factor of the ties' thermal bridging effect. The thermal resistance of the wall assemblies varies greatly with the change of tie material, ranging from 14.68%~41.85%. Using a low thermal conductivity material (e.g., GFRP tie) can almost eliminate the thermal bridging effect of the tie. Enlarging the tie spacing also can improve the overall thermal resistance of walls up to 12%. Using a low thermal conductivity tie material such as GFRP is recommended for effective thermal resistance improvement for the masonry wall cavity wall assembly.

Download or read book A Practical Method to Estimate the Effective Thermal Resistance of Exterior Masonry Walls written by Maysoun Ismaiel and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evaluation of the thermal resistance of building envelope elements is essential for a reliable assessment of the thermal behaviour and energy efficiency of buildings. Energy codes continue to drive the building construction industry toward more stringent thermal performance standards. To reduce energy consumption in buildings and comply with newer, more stringent energy code requirements, evaluation of the thermal resistance of above-grade wall assemblies is becoming essential. Masonry veneer cladding is typically supported by the building structure using intermittent anchors and shelf angle bearing supports. However, elements with high thermal conductivity, such as floor intersections and cladding attachment systems, often penetrate the insulation and cause thermal bridging. Thermal bridges have a significant reduction effect on the elements' thermal resistance. Moreover, condensation on thermal bridging elements is expected. As a result, damage to building elements occurs. In terms of calculating the effective thermal resistance (R-value), the lateral heat flows caused by these highly conductive elements allow heat to be transferred in multiple directions, which is considered a challenge in the R-value estimations and causes the inability of a quick estimate of the effective thermal resistance of masonry components with sufficient precision due to the complexity of masonry construction. Currently, an accurate estimation of the R-value of masonry walls is a time-consuming task, which lengthens the design process, especially in the early design stage. Therefore, this study aims to provide efficient approaches for estimating the R-values of common concrete masonry cavity walls. Two estimation approaches are presented. First, the estimation of the R-value of common concrete masonry veneer wall configurations is presented in the form of simple design charts and R-value multipliers. Parameters such as the concrete block density, thermal insulation value, as well as the types of ties and shelf angles are addressed. The approach provides simultaneously the mechanical (the masonry compressive strength, fm') and thermal (R-value) properties of different veneer wall configurations, allowing designers to obtain appropriate structural and thermal properties during the preliminary design phase. In addition, the design charts and R-value multipliers help designers evaluate and compare the impacts of changes in different parameters on R-values, thereby facilitating their design development. A comparison of the impacts of different parameters on the thermal resistance of masonry walls was presented. The results showed that the thermal resistance of masonry cavity walls was improved by using different tie types and materials. In the case of using galvanized, stainless-steel and Glass Fiber Reinforced Polymers (GFRP) perforated fastened on block's surface ties, the thermal resistance improved by 25%, 43% and 60%, respectively, compared to the traditional galvanized solid block ties. Using knife plate galvanized and stainless-steel shelf angles in the intermediate floor intersection assemblies improved the overall average R-values by 30% and 63%, respectively, compared to the traditional galvanized steel directly attached shelf angle. Moreover, the results showed that the shape and material of the ties and shelf angles are more effective in the masonry wall assemblies with higher insulation R-values. Also, the effect of the concrete block density was addressed, and the results showed that, on average, the reduction of the concrete block density by 10% showed an improvement in the effective R-value of 3.5%. In addition, configurations with an expected lower effective thermal resistance are more sensitive to the concrete block density. Also, cases using solid ties are more sensitive to block density reduction than cases using perforated ties. The second approach provides adjustments to current analytical methods of thermal resistance estimation (i.e., isothermal plane and parallel path methods) to include the effect of the thermal bridge resulting from veneer ties and slab intersections. The R-values obtained from the suggested adjustments were compared with numerical simulations using a 3D steady-state finite element method (FEM) in addition to experimental validation obtained from the literature. The clear wall adjustment factors result showed an average accuracy of 2% in the case of using the suggested adjustments, compared to 19% and 25% for isothermal plane and parallel path methods, respectively. With the presented approaches, designers can choose the optimum wall components' material properties in the early design phase to meet structural and thermal requirements without using computer simulations or experimental investigations.

Download or read book Evaluating the Impact of Moisture Content on Thermal Resistance of Mass Masonry Wall Assemblies written by Rex A. Cyphers and published by . This book was released on 2020 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thermal resistance of a wall assembly is one of the key factors that is considered when evaluating the contribution of the building envelope to the overall energy performance of new and existing buildings. The conductivity and thickness of the building materials comprising the wall assembly are used to determine the theoretical thermal resistance of a given wall assembly. While the thickness of the materials is generally unchanged, the conductivity of the material will vary depending on its exposure to moisture. The moisture content of a building material can be impacted by direct exposure to bulk water, such as during a rain event, or also through the transmission of water vapor. Because water will conduct heat at a greater rate than most building materials, an increase in moisture content within a wall assembly will result in a decrease in the overall thermal resistance. Published data for the thermal resistance of typical building materials do not account for changes in moisture content. Over time, the thermal resistance of a wall assembly will fluctuate and may not be captured accurately based on current design and modeling methodologies. Field data were collected for existing mass masonry wall assemblies using an assortment of data logging instrumentation to measure the in situ thermal resistance and moisture profile across the wall assembly. These data were analyzed to determine the impact that periods with elevated moisture levels within the wall assembly had on the measured R-value.

Download or read book Ceramic Abstracts written by and published by . This book was released on 2000 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Brick and Block Masonry From Historical to Sustainable Masonry written by Jan Kubica and published by CRC Press. This book was released on 2020-07-06 with total page 1097 pages. Available in PDF, EPUB and Kindle. Book excerpt: Brick and Block Masonry - From Historical to Sustainable Masonry contains the keynote and semi-keynote lectures and all accepted regular papers presented online during the 17th International Brick and Block Masonry Conference IB2MaC (Kraków, Poland, July 5-8, 2020). Masonry is one of the oldest structures, with more than 6,000 years of history. However, it is still one of the most popular and traditional building materials, showing new and more attractive features and uses. Modern masonry, based on new and modified traditional materials and solutions, offers a higher quality of life, energy savings and more sustainable development. Hence, masonry became a more environmentally friendly building structure. Brick and Block Masonry - From Historical to Sustainable Masonry focuses on historical, current and new ideas related to masonry development, and will provide a very good platform for sharing knowledge and experiences, and for learning about new materials and technologies related to masonry structures. The book will be a valuable compendium of knowledge for researchers, representatives of industry and building management, for curators and conservators of monuments, and for students.

Download or read book Miscellaneous Publication written by and published by . This book was released on 1979 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Register of Research written by and published by . This book was released on 1975 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ASHRAE Journal written by and published by . This book was released on 1986 with total page 1056 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sustainability in Energy and Buildings 2021 written by John R. Littlewood and published by Springer Nature. This book was released on 2021-09-28 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter “A Multi-functional Design Approach to Deal with New Urban Challenges” is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.

Download or read book Solar Energy and Nonfossil Fuel Research written by and published by . This book was released on 1979 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: This directory--the first annual compilation of agriculture-related solar energy research--is designed to provide the scientist, technician, and inventor; government and industry; and farmers and other interest laymen with an overview of the diverse and intense efforts being mounted by our society to find alternate energy sources.

Download or read book Register of Research 1975 written by Great Britain. Department of the Environment and published by . This book was released on 1975 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book List of Chemical Compounds Authorized for Use Under USDA Meat Poultry Rabbit and Egg Products Inspection Programs written by and published by . This book was released on with total page 832 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Concrete at High Temperatures written by Zdeněk P. Bažant and published by Prentice Hall. This book was released on 1996 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the increased use of concrete in high temperature environments, it is essential for engineers to have a knowledge of the properties and mathematical modelling of concrete in such extreme conditions. Bringing together, for the first time, vast amounts of data previously scattered throughout numerous papers and periodicals, this book provides, in two parts, a comprehensive and systematic review of both the properties and the mathematical modelling of concrete at high temperatures. Part I provides a comprehensive description of the material properties of concrete at high temperatures. Assuming only a basic knowledge of mathematics, the information is presented at an elementary level suitable for graduates of civil engineering or materials science. Part II describes the response of concrete to high temperatures in precise terms based on mathematical modelling of physical processes. Suitable for advanced graduate students, researchers and specialists, it presents detailed mathematical models of phenomena such as heat transfer, moisture diffusion, creep, volume changes, cracking and fracture. Concrete at High Temperatures will prove a valuable reference source to university researchers and graduate students in civil engineering and materials science, engineers in research laboratories, and practising engineers concerned with fire resistance, concrete structures for nuclear reactors and chemical technology vessels.

Download or read book Sustainable Masonry written by Thierry Ciblac and published by John Wiley & Sons. This book was released on 2014-07-22 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the impact of sustainable masonry on the environment, touting the many benefits of utilizing local and/or low embodied energy materials in the construction of sustainable buildings.

Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna tional publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 34 (thesis year 1989) a total of 13,377 theses titles from 26 Canadian and 184 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work. While Volume 34 reports theses submitted in 1989, on occasion, certain univer sities do report theses submitted in previous years but not reported at the time.

Download or read book Rapid Visual Screening of Buildings for Potential Seismic Hazards Supporting Documentation written by and published by Government Printing Office. This book was released on 2015 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Rapid Visual Screening (RVS) handbook can be used by trained personnel to identify, inventory, and screen buildings that are potentially seismically vulnerable. The RVS procedure comprises a method and several forms that help users to quickly identify, inventory, and score buildings according to their risk of collapse if hit by major earthquakes. The RVS handbook describes how to identify the structural type and key weakness characteristics, how to complete the screening forms, and how to manage a successful RVS program.