The paper deals with the principles of structure, function, use, disfunction and repairs of framework (part 1 to 5).
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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.
Between 1975 and 1985, many gyms of T18 type were built in Czechoslovakia. These gyms were mostly intended for schools, specifically primary schools. The manufacturer of these structures was Bučina Zvolen. The index T18 relates to the span of the load-bearing structure which amounts to 18 meters. The ground-plan measurements are 18,8 by 41,15 m.
The gyms were designed as low-cost structures, which also affected the length of their useful life – 20 to 25 years. In the present, many of these structures are still in use even though they are over 40 years old. Since there has been no refurbishment of these structures to this day, they fail to meet any normative criteria, especially concerning the thermal protection of the structure. Due to unsystematic maintenance, defects have in many cases occurred on the load-bearing members. These can result in limits to the structure’s usage and eventually to its complete shutdown. Under some conditions, it is possible to lengthen the useful life of the gym and it should be in the interests of its owners to be able to continue using it. Based on the diagnostics performed on the specific structure in Želiezovce (Slovakia) and the data collected from other gyms of this type, the authors of the presented contribution have elaborated the static calculation of the load-bearing timber structure for the case of enhancing the heat insulation properties to meet the European standards.
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.).
The contribution dealst with the problematics of statical defects, or more precisely with the formation of cracks in the brickwork caused by the effect of technical seismicity. It further deals with the construction principles which can be used when designing reconstruction of buildings which are located within the reach of the effect of technical seimicity. The problematics of historical buildings and conservation areas is also mentioned.
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.
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.
The article deals with hot-air treatment of a historically valuable Rožnov town office, built in 1770, which was transported to the Wallachian Open Air Museum in Rožnov pod Radhoštěm in 1924 as the first building of the currently extensive premises of this national cultural heritage. The method of wooden structure hot-air treatment was used for the first time in the territory of the Czech Republic in 2010. It has been used in western European countries (especially Denmark and Germany) approximately since 1930. This comprehensive method is governed by the German standard DIN 68 800 – Part 4 [1] and it is especially used for historically valuable buildings where emphasis is put on the preservation of the original wooden structure attacked by wood-destroying insects, usually of the long-horn beetle family (Cerambycidae) oranobium beetle family (Anobiidae). The goal of the article is to explain the hot-air treatment method to professional public using an example of one of implementations.
Water vapour permeability is one of significant material properties. The value of water vapour resistance factor is necessary to know to be able to rehabilitate structures, mainly after floods. One thing is essential – to know what are the values of water vapour resistance factor of the used material to know how long the structure will take to be dried and users can come back to live there.
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 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.
During the assessment of existing structures of monuments made from reinforced concrete is always necessary to verify the properties of concrete and placement of reinforcement. The paper deals with testing of concrete by non-destructive methods – especially by hardness test method and ultrasonic method. For testing of historical structures seems to be the most suitable ultrasonic method.
Within the reconstruction of town hall premises, the authorities of a district town decided to rebuild existing ramshackle group house radically. The house is located in a historic area of the city and therefore some parts of the house, namely the medieval cellars and street front, are listed. In addition, the adaptation of the underground spaces, facades and gable walls was necessary, too. In the course of designing process and also during the reconstruction works, the drawings had to be repeatedly revised, partly quite fundamentally.
The article introduces the new method “Lapped Scarf Joints for Historical Structures Repairs” that deals with design of the lapped scarf joint suitable for the reconstruction of valuable historical timber structures, with help of making the prosthesis for the damaged parts of the beams. The method is a result of the four-year research project supported by the Czech Ministry of Culture within NAKI program. Institute of Theoretical and Applied Mechanics AS CR, Faculty of Civil Engineering CTU and Faculty of Forestry and Wood Technology of Mendel University participated in the research.