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Archiv článků od 21.10.2019 do 17.11.2024

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17.11.2024
Ing. Jakub Vrána, Ph.D., Ústav TZB, Fakulta stavební VUT v Brně

The article discusses the history of sanitation installation, i.e. water installation, drainage systems inside buildings and gas installation pipework for buildings from the earliest times to 1948 and is primarily focused on the history of this field in the territory of the former Czechoslovakia. It also deals with the history of the plumbing trade, contemporary legal regulations, technical standards and professional literature on the territory of the former Czechoslovakia.

28.10.2024
Ing. Jan Trejbal, Ph.D., doc. Ing. Václav Nežerka, Ph.D., Tomáš Zbíral, doc. Ing. Jan Valentin, Ph.D.

The efficient classification of materials in construction debris is crucial for their sorting and further valuable utilization. Current methods, whether relying on force sorters or separators, are reaching their limitations. In many cases, construction and demolition waste materials end up being downcycled or even sent to landfills. Our contribution is divided into two parts. The first part presents facts relating to the production of construction and demolition waste in the EU and justifies the urgency of responsible waste management. It also recaps the development of indirect methods of classification and briefly describes types of suitable sensors for material observation and algorithms for data evaluation. The second part describes our classification solution, developed by the faculties of civil engineering and electrical engineering at CTU in Prague. This method is based on the evaluation of data obtained with ordinary RGB cameras.

7.10.2024
doc. Ing. Michal Stehlík, Ph.D., VUT FAST Brno, Ústav stavebního zkušebnictví

The article presents a project submitted by TAČR in the Environment for Life section 2. The goal of the project is to find the application of recycled glass fractions from photovoltaic panels in the field of construction. The project focuses on three basic silicate building materials, which are able to incorporate glass recyclate shards into their structure during the hydration, firing and melting process. The paper specifies the first results of testing possibilities for use of glass recyclate from photovoltaic panels for concrete masonry units. It compares particular recipes and its physical and mechanical properties with the main focus on the compressive strength. It then compares the values of these recipes with the values of commonly used composite materials for masonry units without recyclates.

29.7.2024
doc. Ing. Miroslav Škopán, CSc., VUT v Brně, asociace ARSM

The paper deals with the analysis of mineral construction and demolition waste management in the Czech Republic between 2007 and 2022. The analysis is based on data from the Czech Environmental Information Agency. It has been shown that the production of recycled mineral construction and demolition waste has quadrupled in this period and that the share of recycled mineral construction waste in the market of mineral materials for the construction industry is around 15%.

27.5.2024
Ing. Zdeněk Prošek, Ph.D., doc. Ing. Pavel Tesárek, Ph.D., Ing. Hana Sekavová, Ing. Jiří Podolský

In the presented paper, the results of the use of modified gypsum-based recyclate obtained from construction and demolition waste are analyzed. The selected recyclate comes from a real construction site of Moravostav Brno, a.s. and was subjected to modifications using a newly developed gypsum plasterboard recycling line. During the research, the influence of the recyclate treatment, especially in terms of grinding fineness, on the key properties of the dry gypsum mixture was monitored. Substitution of gypsum (or gypsum binder) in the mix was carried out in proportions of 10, 25 and 50 wt%. The resulting properties, such as bulk density, flexural tensile strength, compressive strength, volumetric changes and shrinkage, were monitored after 7 days of sample production.
In a follow-up step, gypsum blocks using treated gypsum recyclate and the designed dry gypsum slurry were semi-produced at Moravostav Brno, a.s. in January 2024. A segment of the wall was constructed from the blocks.
The results obtained clearly show that with appropriate treatment, it is possible to effectively replace part of the gypsum binder in the dry gypsum mixture using modified gypsum recyclate. These findings provide important information for the advanced use of gypsum plasterboard recycling in the construction industry, while highlighting the potential for more sustainable and environmentally friendly practices in building materials.

13.5.2024
Ing. Stanislav Bedřich

By digitizing and automating processes throughout the building life cycle, the goal is to optimize the use of information so that it can be easily used either to reduce waste from buildings (waste prevention) or to have sufficient information about the materials and products used in the building at the end of its life cycle or as part of various renovations or retrofits. At the same time, improving the planning and management of the waste generated is a key effort. The paper presents the results of the European RECONMATIC project in this area, which progressively links information efficiency approaches with BIM processes. As such, the project has a broader focus and represents a paradigm shift in the management of C&D materials, from the traditionally conservative approach to C&D waste, to a similarly conservative approach of the construction industry, to construction production that seeks to achieve high waste recovery rates, and to the adoption of a responsive approach to waste recovery. The technologies to be used in this project (creating and working with a digital twin of the building, blockchain-based applications, precision prefabrication, efficient sorting through automation and robotics, etc.) are part of the themes that the project focuses on.

16.4.2024
Ing. Aleš Choutka, ředitel EKOLOG jinak

The article thoroughly describes the role of a corporate ecologist in complying with environmental regulations within businesses. In addition to traditional areas such as waste management, packaging materials, chemicals, and accident prevention, it now focuses on ESG reporting. It emphasizes trends towards sustainable waste management and the circular economy. The text analyzes strategies for waste prevention, trends, and innovations in their processing. Finally, it highlights the importance of education and awareness in this field.

24.4.2023
Dr. Ing. Libor Čapla, doc. Ing. Václav Koza, CS.c.

The composition of natural gas in the Czech distribution system, or the Czech part of the former Czechoslovak system, has not changed too much over time to date. Almost all of the gas was that supplied from the former Soviet Union and, following its disintegration, from Russia mainly to western European countries and met their requirements. The situation completely changed in 2022 when gas supply from Russia to the EU was reduced and large quantities were replaced with LNG. In this context, the contribution discusses the changes in the composition of the natural gas distributed in the Czech Republic.

Model tepelného čerpadla v Malmo (Zdroj: GEA)
3.1.2023
Ing. Erika Langerová, Ing. Nikola Pokorný, Ph.D., doc. Ing. Tomáš Matuška, Ph.D.

High-temperature water-to-water compressor heat pumps with different refrigerants and configurations can be used in district heating systems operating at temperatures between 60 and 120 °C. Part 1 describes the development of installations in Europe and the current state of development, including an overview of the market offer.

2.1.2023
Ing. Erika Langerová, Ing. Nikola Pokorný, Ph.D., doc. Ing. Tomáš Matuška, Ph.D.

High-temperature water-to-water compressor heat pumps with different refrigerants and configurations can be used in district heating systems operating at temperatures between 60 and 120 °C. Part 1 describes the development of installations in Europe and the current state of development, including an overview of the market offer.

28.11.2022
doc. Ing. Miroslav Škopán, CSc., VUT v Brně, asociace ARSM

The article provides an overview of the development of construction and demolition waste recycling in the Czech Republic in the period between 2007 and 2020. Waste group 1701 concrete, bricks, tiles and ceramics analyzed in more detail. Recycled C&DW from this group are assessed in terms of the possibility of their use as concrete filler. Attention is also paid to group 170504 – soil and stones without hazardous substances. A significant increase in recycling has been demonstrated for this group in recent years. In conclusion, the ratio of recycled C&DW and extracted natural mineral raw materials in the construction industry is analyzed.

23.6.2022
Ing. Zdeněk Reinberk, Ph.D., redakce

A nuclear power plant is a powerful and stable source of electricity. Full replacement of such source with photovoltaics is not easy. We calculated how much PV panels and batteries would be needed for replacement and how much it would cost. The calculation in the article is interactive and the individual calculation parameters can be modified.

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31.5.2021
doc. Ing. Michal Stehlík, Ph.D., Mgr. Jana Knapová, Ing. Vojtěch Kostka

The paper deals with the possibilities for use of glass recyclate from photovoltaic panels for concrete masonry units. It compares partivular recipes and its physical and mechanical properties with the main focus on the compressive strength. It then compares the values of these recipes with the values of commonly used composite materials for masonry units without recyclates.

19.4.2021
Ing. Kristina Fořtová, Ph.D., Ing. Diana Mariaková, Ing. Jakub Řepka, Ing. Tereza Pavlů, Ph.D.

This article deals with the possibility of using masonry aggregate from construction and demolition waste. The article summarizes the properties of concrete with a laboratory-optimized recipe with a full replacement of natural aggregate with recycled masonry aggregate. Testing of concrete samples was carried out according to valid standards. The result is a mixture with optimized properties for the production of construction parts.

15.3.2021
Ing. Josef Fík, Dr. Ing. Libor Čapla, Ing. Jiří Žahourek, CSc.

The authors analyze the possibility of burning natural gas with an admixture of hydrogen in gas appliances. The positive and negative aspects of the hydrogen content in natural gas and recommendations for its mixing into the natural gas distribution system are presented.

The contribution describes the effect of hydrogen content ranging from 0 to 25 mol% in a mixture with natural gas on burning in household appliances. Gaseous fuels with similar combustion characteristics, in particular Wobbe index and burning velocity, can only be used in a particular household appliance as a substitute. The various chapters describe the effect of hydrogen content in natural gas on the following: Wobbe index, composition of exhaust gases; emissions of CO2, CO and NOx; burning velocity; output of burners/energy demand of appliances, efficiency of appliances; flame stability; and temperature of combustion. Recommendations on hydrogen content in natural gas for household appliances, accepted from reference literature, are set out there. In conclusion, the authors discuss the pluses and minuses of hydrogen content in natural gas and offer recommendations for hydrogen injection into natural gas distribution systems from the perspective of burning these mixtures in household appliances.

8.3.2021
Ing. Josef Fík, Dr. Ing. Libor Čapla, Ing. Jiří Žahourek, CSc.

The authors analyze the possibility of burning natural gas with an admixture of hydrogen in gas appliances. The positive and negative aspects of the hydrogen content in natural gas and recommendations for its mixing into the natural gas distribution system are presented.

13.4.2020
Ing. Miroslav Havrlent, RACEN, spol. s r. o., Piešťany, Slovensko

Achieving the criteria set for effectively district heating will be a precondition for the development of central heat supply in the coming period. Heating companies are therefore looking for suitable alternative solutions. In this paper it is the view of the designer on a concrete example of the combination of the use of geothermal water and CHP.

9.4.2020
Mgr. Dana Stejskalová, Doucha Šikola advokáti s.r.o.

This article describes a long-term Renewables Power Purchase Agreement under which a consumer purchases renewable electricity directly from an electricity producer. Signing a renewables PPA ensures that the producer acquires the long-term revenue stream through the sale of energy and the costumer gets the fixed electricity price for the entire period of the contract.

21.10.2019
Ing. Jan Blažíček

Decree No. 269/2015 Coll. I consider it one of the worst regulations I have ever encountered. I start from the experience of people who asked me for advice on what to do when they have winter at home and yet the highest share of heating costs in the whole house. At first I bet on the effect of heat parasitizing unoccupied neighboring apartments, but then I thought of looking at positional coefficients.


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