Cellulose insulation is one of the minority types of heat insulating materials, but their use has increased significantly in recent years. The aim of the contribution is to assess the impact of its bulk weight on the processes of smothering and glowing. The resistance wire was used as the initiator. In addition to visual observation, carbon dioxide concentrations and optical smoke density were also recorded. The results were evaluated in the form of graphs and tables.
The article analyses the impact of the new atomic law and its implementing decree on the design of radon preventive and remedial measures in residential buildings. The relationship between the newly introduced reference level and optimisation of the design, that gains importance, is explained. The article also discusses reasons that speak against the provision of the new law that radon index of the building site need not be determined, when a preventive measure based on soil ventilation is being designed.
In December of year 2016 has been finished the extensive reconstruction of the multi-family house built in the thirties of last century, located in the district Žabovřesky of the city Brno. Investor with architect desired the modern appearance of interior and facade of the house, which involved a number of difficult renovations and new structures that had to be consulted with structure engineer. The significant steps of the reconstruction of the multi-family house are described in detail in this contribution.
Requirements to fire safety of ETICS were changed several time during last 8 years to be more strict. Since September 2016, an amendment to fire standard ČSN 73 0810 [8] has entered into force, which, among other things, regulates the requirements for External thermal insulation composite systems (ETICS). In this context, a number of mid-scale and large-scale tests of EPS have been carried out to test equivalent solutions of overheads and foundations of ETICS. With the use of these approved design solutions, it is possible to continue to use advantage of all the benefits of EPS, ranging from insulation properties to moisture, mechanical properties, long service life and stability and end-to-end performance. This contribution deals with proportionality of the ETICS fire requirements.
The paper deals with the development of vacuum insulations from their beginning to the present and their application in the industrial sectors and civil engineering. Development and study of the behavior of environmentally fiendly core insulations for application to vacuum insulation panels is going nowdays at Brno University of Technology, Faculty of Civil Engineering. These are mainly organic materials based on natural or waste polymer fibers. This article describes the first results of the research activities on this issue where test samples of flax fiber insulation were tested, as well as cotton and polyester fibers samples obtained from waste fabrics.
The possibilities of using nanomaterials are quite broad – from increasing the hydrophobicity and photostability of surfaces, through improving the mechanical properties of traditional materials, aiding in the diagnosis and therapy of certain diseases, repairing damaged parts of the tissue, and solving problems in decontamination of the environment. Intensive research also takes place in their applications to increase the resistance of wood to wood-boring fungi and wood-destroying insects. Nanomaterials, including nanocellulose, are perspective in the field of wood fire protection, which may be important in the evolving trend of wood building construction.
The article discusses the defects and failures of synthetic foil waterproofing, which show manufacturing defects, which then lead mainly to shorten the lifetime of waterproofing system, but also their own waterproofing due mainly manufacturing, but structural faults. The article gives examples of analytical, non-destructive methods that can be documented defects in material and demonstrate. At the end of the article is included as a legal commentary on the defects and malfunctions and legal information about how to resolve this issue in terms of the legal system.
The mutual joint waterproofing aspfalt strips can in practice be done in different ways. But not everyone is the correct one. Also important is the width of the overlapping associated strips. We will deal with strongholds in the modified stress and oxidized asphalt strip and compare the strength of the joints. If the bitumen is used as additional waterproofing is necessary, select the types of bitumen sheets with matching suitable bearing insert. As a waterproofing type we should use the modified asphalt strip. The issue of reliability of waterproofing is associated with a high quality of work performed. This quality is affected not only the human factor, but also the technology used for implementation of waterproofing layers. Another influencing factor is the type of applied asphalt waterproofing strip.
The cause of moisture in the masonry could by different. By old historical buildings is the problem in absence of hydro-insulation, which was made by flat stones or clay backfill. New buildings have a lot defect by application (for example: pipes penetration, join) or wrong design of hydro-insulation, which are the point infiltration of water in to the construction. This problems are made by wrong projection of hydro-insulation in the project. The project does not reflect all influences of the water. But they are also another cases, which can happened like river floods, flood by the neighbour. In those cases it is demanding to dry the building as soon as possible, to protect the property from the mold and return the function of the building. One of the method, which is suitable for this solution is microwave dehumidification, which realize all conditions in one. This aim include also the practice example of the microwave sanitation technique, used by dehumidification masonry, and the positive results.
The definition of what is a common part of a residential building is essential especially when modifying the building structures and eliminating defects that affect both a common part and residential units. How common parts are defined affects who finances the modifications and reconstructions of such structures and parts. The definition of common parts is based on the new Civil Code (No. 89/2012 Coll.) and on the already abolished Act on Ownership of Housing (No. 72/1994 Coll.).
For excessive wet masonry rehabilitation, except for other methods, the method of air cavities is used. These can be wall or floor cavities. The wall cavities may be situated either on the internal or the external side of the wall. From the height point of view, internal side cavities can be located under the floor or above the floor level. This contribution only deals with the cavities above the floor level. In the projection practice, the air cavities usually are designed only empirically. But it is necessary to carry out their thermal-technical evaluation for their correct capacity. The matter of the evaluation is the topic of the following contribution.
U-value calculation of curtain walling is one from more difficult calculation in the civil engineering. In according to trend of increasing glassing surface of building envelope, the curtain walling has big influence on thermal behaver of buildings. This is why it is necessary to calculate the thermal insulation properties with special attention. This article focuses on influence of different local thermal bridges on curtain walling U-value.
This paper discusses the practical use of microwave technology in construction practice. Opinions on the use of EMW devices are not only among the general public quite different. From boundless praise, to the uncritical condemnation. The reason for this situation is the lack of awareness of experts and the public about what is and what is not possible to expect from this technology.The article conclusions which we reached on the basis of experiments conducted at the Faculty of Civil Engineering Brno and subsequently verified measurements in field practice. The aim is to provide basic information about how to use microwave technology. Their benefits but also the risks that this technology brings along.
Natural building materials are in recent years used still more often in civil engineering. One of these materials is also the straw. By its crushing and cutting into small pieces it is formed so-called crushed straw. The properties of this material, which are important for civil engineering, were not published yet unlike the properties of the straw in bales. In the Czech Republic there exist a many objects built from straw bales. In this paper there are described partial results of research which is implemented on Faculty of Civil Engineering, VSB – Technical University of Ostrava since 2013. The aim of this research it is to set fire resistance, thermal – technical properties and acoustical characteristics of crushed straw. There are described results of fire tests – flammability test and tests of single burning object (SBI). Subsequently there are referred results of thermal conductivity measurements, which were provided for different bulk densities of crushed straw.
The removal of unwanted material from the surface of historical artefacts is one of the most important and also the most delicate operations in the restoration of cultural heritage. In the Center for innovations in the field of nanomaterials and nanotechnologies a novel design concept of the cleaning microemulsions was developed based on a combination of the two functions, implemented by two components, namely a micellar solution or microemulsion of nonionic surfactants with the addition of co-surfactants and the specific solvents, which are selected according to the respective substances to be removed. The patented cleaning compositions can very effectively and selectively remove coatings of many substances important for the restoration practice, such as waxes, resins (e.g, Damara), paraffins, oils, water acrylate dispersions, hydrophobization coatings (both monomeric and polymeric) etc. Besides the efficient cleaning, the developed procedures have wider applications, such as in a new method of the hydrophobization of sandstone and limestone materials with a thin hydrophilic surface layer, which has been certified by the Ministry of Culture of the Czech Republic.
Non-aqueous dispersions of nanoparticles of calcium hydroxide and magnesium are principally suitable means for the consolidation of wall paintings and limestone materials because they are compatible with the material of historical artefacts. They are also suitable for the deacidification of paper and wood. In the Center for innovations in the field of nanomaterials and nanotechnologies procedures were developed which provide nanoparticles of calcium hydroxide and magnesium ranging in size from about 10 nm to about 200 nm. The procedures are relatively experimentally challenging and put them into practice will require further technological research. Thanks to the good stability of the dispersion a sufficiently long shelf life is ensured and premature aggregation on the surface or just below the surface of treated materials is prevented. There are several alternative methods of the consolidation stone, as exemplified by the use of alkoxides of calcium or magnesium. In converting the alkoxide to calcium carbonate, the sole by-product is alcohol, which naturally evaporates from the stone.
For more than a year, a nearly zero-energy standard has applied to certain buildings. In the Czech environment, specific technical parameters for such buildings have been known for three years. And for over six years, the Directive on energy performance of buildings has been in force, imposing the obligation upon EU member states to introduce this standard.
Nevertheless, it seems that for many experts, including those in the field of energy, this term is still quite unclear. Many imagine buildings coated with photovoltaic modules from the ground to the roof, buildings which are better than passive ones or buildings which are self-sufficient, i.e. completely independent of public energy networks. Given the fact that the concept of a nearly zero energy building is very distant from such notions, and because this standard will soon become obligatory for all buildings, including small family houses, let's have a look at what a nearly zero-energy building really is.
The paper presents an example of solving the propagation of noise from an air/water heat pump installed in the basement of an apartment building. Air intake and exhaust are brought out on the façade of the building, where it is calculated the noise situation in the protected exterior of the building. In the interior it is solved the propagation of sound from the plant room to the protected interior space. In conclusion, the results are compared with the data from the report on measurement at the realized work.
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