![]() ![]() The article covers three topics: firstly, the properties and applications of silica aerogel then, the main achievements of recent years in aerogel cement composites and lastly, the most important aspects related to the durability and performance of these composites. The aim of the article is to present the most important trends in the synthesis and physical properties of cement composites modified with silica aerogel granules. Nanomaterials that may find wider use in the construction industry are silica aerogels and their composites, including those that are cementitious-based. Indeed, according to research center predictions, nanotechnology will play increasingly larger roles within the next several dozen years in the production of innovative materials for construction. The EU lists this area of research in the document called “Roadmap 2014” as a key one. The application of nanotechnologies in construction enables the design and modification of material structures so that we receive a product with the expected strength and some special directional properties, such as resistance to external physical and chemical factors, as well as being self-cleaning, antibacterial or self-repairing. An essential condition in overcoming these complex issues is developing new building materials that have high strength and durability and, at the same time, are safe for human health and for the natural environment. Some of the most important challenges in today’s construction industry are ensuring the safety, durability and reliability of buildings. For this reason, novel materials combining low thermal conductivity and density with high compressive strength should be developed for building applications. ![]() This performance may only be achieved either by installing extremely thick conventional insulation materials, by sacrificing living spaces or by using materials of very low thermal conductivity and density without limitations in compressive strength. In addition, there is still a problem with existing buildings and how to upgrade them under current insulation conditions. ![]() Unfortunately, this criterion has not been met in many European countries and the time to achieve restrictive requirements has been extended for the coming years. To address this, the Energy Performance of Buildings Directive (EPBD) 2010 required that, by the year 2020, almost all new constructions were to be “Nearly Zero Energy Buildings”. Solving these issues will certainly contribute to the wider applicability of these materials in the construction industry.Īpproximately 40% of all energy consumption and 36% of all CO 2 emissions in Europe stem from residential and industrial buildings due to inefficient insulation materials and systems. The article also points out the weaknesses of the application of silica aerogel in the cement matrix, the most important of which are the lack of adhesion at the boundary of the aerogel–cement binder, the increased porosity of the composite, the high water absorption capacity and the significant decrease in compressive strength with large volumes of silica aerogel. Therefore, in recent years, more and more elements of the hygrothermal performance, porosity and durability of silica aerogel cement composites have been developed. Other important standpoints are water transport and moisture protection of the silica aerogel-based coatings. In turn, the prerequisites for using aerogel cement composites as coatings for energy-efficient building façades are the use of large amounts of silica aerogel as a substitute for lightweight aggregates or the selection of an optimal composition of lightweight aggregates and aerogel, ensuring the lowest possible thermal conductivity coefficient.
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