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Zjednodušený princip přenosu zvuku přes dělící trámovou konstrukci
29.1.2024
Ing. Lubor Kalousek, Ph.D., Ing. Zuzana Fišarová, Ph.D., Ing. Zdeněk Vejpustek, Ph.D.

The article is focused on the issue of traditional timber joist floor structures and floor compositions from the period up to the first half of the 20th century. In building practice, we very often encounter these structures in residential buildings that are the subject of structural changes. During these interventions, the basic ideas of the original technical solution are not always respected and some physical parameters of building are degraded. The article describes the principles that were devoted to these types of structures in historical legislative and standard regulations and further in professional literature. The original historical solutions are presented on a practical example. In relation to building interventions in historic timber joist floor structures, current legislative and standard regulations are described, as well as examples of modern solutions and their limitations.

Příklad obvyklého řešení dřevěného trámového stopu v obytných budovách
22.1.2024
Ing. Lubor Kalousek, Ph.D., Ing. Zuzana Fišarová, Ph.D., Ing. Zdeněk Vejpustek, Ph.D.

The article is focused on the issue of traditional timber joist floor structures and floor compositions from the period up to the first half of the 20th century. In building practice, we very often encounter these structures in residential buildings that are the subject of structural changes. During these interventions, the basic ideas of the original technical solution are not always respected and some physical parameters of building are degraded. The article describes the principles that were devoted to these types of structures in historical legislative and standard regulations and further in professional literature. The original historical solutions are presented on a practical example. In relation to building interventions in historic timber joist floor structures, current legislative and standard regulations are described, as well as examples of modern solutions and their limitations.

Princip práce s W-diagramem
15.1.2024
doc. Ing. Jan Kaňka, Ph.D., Ing. Bc. Jaroslav Vychytil, Ph.D.

The article deals with the description of selected graphic-numerical methods used to determine the amount of daylight. The principle of derivation of these methods is explained and the principle of working with the relevant diagrams is described. Nowadays, we rarely see the use of diagrams in practice, but some professional software uses them either directly or at least in their graphical outputs.

Fotometrie činitele denní osvětlenosti, doc. Ing. Jan Kaňka, Ph.D.
8.1.2024
doc. Ing. Jan Kaňka, Ph.D., Ing. Bc. Jaroslav Vychytil, Ph.D.

The article deals with the description of selected graphic-numerical methods used to determine the amount of daylight. The principle of derivation of these methods is explained and the principle of working with the relevant diagrams is described. Nowadays, we rarely see the use of diagrams in practice, but some professional software uses them either directly or at least in their graphical outputs.

11.12.2023
doc. Ing. Jan Kaňka, Ph.D., člen TNK 76 Osvětlení, ČKAIT Praha

The paper deals with the uniformity of daylight in living rooms. It investigates the effect of the way the size and location of the living space in the living room is determined on the uniformity of light.

© Fotolia.com
13.11.2023
Ing. et Ing. Lenka Gábrová, Ph.D., Ústav pozemního stavitelství, Vysoké učení technické v Brně, Fakulta stavební

The article deals with daylighting assessment in habitable rooms according to the currently valid Czech Standard ČSN 73 0580-2 and according to the Draft Czech Decree on Requirements for Constructions. The case study investigates and compares the daylighting availability in rooms which meet the requirements stated in the draft decree.

23.10.2023
Ing. et Ing. Eva Šoulová, Vysoké učení technické v Brně, Fakulta stavební, Ústav pozemního stavitelství

Textile and leather wallpapers are an integral part of the interior of historic buildings. These types of wallpaper are specific in their construction, where they are stretched on wooden frames and form a membrane in front of the wall. Verification of diffusion properties is one of the steps to elucidate the thermal-humidity behaviour of these historical structures. Knowledge of diffuse properties is important for architectural and historical surveys and for the reconstruction of historical buildings. Based on this knowledge, we can assess other properties of wallpaper construction, such as moisture and microbial climate.

© Adobe Stock motortion
9.10.2023
Ing. Tomáš Hrádek, AVETON, s.r.o.

The standard “ČSN 73 0527 Acoustics – Acoustical design of rooms – Rooms for cultural uses – Rooms in schools – Rooms for public purposes” was revised after 18 years. In the framework of this revision, the regulations for determining the optimum reverberation time were updated, especially in relation to commonly used technologies and trends in the use of the spaces in question. A new methodology for determining the standard of acoustic treatment for spaces with lower acoustic requirements was developed and, last but not least, a code for occupancy calculations for measuring reverberation time in unoccupied spaces was defined.

tepelné ostrovy ve městech
23.7.2023
Ing. Jan Vystrčil, Ing. Ondřej Nespěšný, doc. Ing. Karel Šuhajda, Ph.D., Ing. David Bečkovský, Ph.D.

As heat islands are referred areas in urbanized cities where the temperature is significantly higher in the summer than in their surroundings. With advancing climate change, the occurrence of heat islands is more numerous. It is obvious that construction has a direct effect on the creation, or on the contrary, on the regulation of heat islands in cities. Due to the available possibilities of 3D modelling of objects and projecting with the help of the BIM method, it is possible to carry out numerical simulations of the effect of objects on the surroundings and monitor the indicators of the formation of a heat island. Building objects can therefore be designed with a high regard for the environmental aspect of the project. This paper describes selected options for numerical modelling of heat islands.

Foto © djama - Fotolia.com
1.3.2023
Bc. Jaroslav Lédl

The paper deals with the effect of all-metal anchors of suspended facades on the heat transfer coefficient of double skin walls. The thermal properties of the anchors are described by means of the point heat transfer coefficient, which can be obtained using a derived formula or calculation aid.
The data for the derivation of the formula and the calculation aid were obtained by three-dimensional modelling and analysis of the calculated data in the framework of the thesis [2]. The input data and the necessary documents used for the calculation were provided by H&B delta. The thesis thus provides a simple calculation and possible comparison of several material and design variants of the used all-metal anchors.

2.7.2022
Ing. David Jun, Ing. Ondřej Nespěšný

The sound absorption coefficient is one of the most common quantities describing the acoustic behaviour of materials and structures intended for use in room acoustics. This contribution first shows a brief overview of techniques for measuring sound absorption coefficient. Special attention is paid to the impedance tube (often called Kundt tube) group of methods. The following is an introduction to the measurement of the transfer-function method and to a developed impedance tube prototype, including both the hardware assembly and the software implementation of the measurement.

Císařský špitál na Pražském hradě
22.12.2021
doc. Ing. Eva Burgetová, CSc., Ing. Denisa Boháčová

The article presents a structural survey of the historic building of the Imperial Hospital at Prague Castle. The aim of the survey was to determine the functional capability and durability of the building, including an assessment of its usability and evaluation of the condition of historical materials. The research was focused mainly on the issue of inappropriate interventions performed in the past and the associated increased moisture of structures.

Stěna porostlá zelení
19.12.2021
Ing. Jana Bartlová, VUT FAST v Brně, Ústav stavitelství

Greening of the cities (Green Architecture) is one of the current trends in the development of urban architecture. Apart from the system elements of facades overgrown or planted with vegetation, which are a question of the current century, the Green Architecture also includes the traditional use of plants - direct planting near building structures, with their gradual connection using climbing and attachment mechanisms of plants. The effects of such a surface on traditional and modern building surfaces have not yet been precisely defined. The paper presents the results of moisture measurement of the outer surface of traditional building structures in order to evaluate the effect of vegetation surface on the structure.

prosluněný interiér © Stock Adobe
2.8.2021
doc. Ing. Jan Kaňka, Ph.D., člen TNK 76 Osvětlení, ČKAIT Praha

To properly understand the meaning of standardization of daylight, it is necessary to think in general about the reason for the existence of standards and the means of their creation. Such a consideration may have its current significance at this time, when the European Commission for Standardization (CEN) unified standards for daylighting of buildings throughout Europe and when the Chamber of Deputies of the Parliament of the Czech Republic approved a new building law.

26.3.2021
Ing. Ondřej Nespěšný, Ing. David Jun, doc. Ing. Jan Pěnčík, Ph.D., Ing. Zuzana Fišarová, Ph.D.

The Helmholtz resonator is one of the most widely used low and medium frequency attenuation acoustic absorbers. While commercial products usually offer efficiency across almost the entire spectrum under consideration, in many cases only the specific natural resonance of the room needs to be suppressed. In such cases, it is necessary to proceed with your own design. This paper presents one of the possibilities of calculating a perforated resonator using the electro-acoustic analogy and the transfer matrix method. This method is not demanding on computing power, but nevertheless it is rarely used in current building-acoustic practice. This paper focuses on the comparison of the calculation of the sound absorption coefficient by this method with the data measured in the reverberation room.

15.3.2021
doc. Ing. Jan Kaňka, Ph.D., člen TNK 76 Osvětlení, ČKAIT Praha

The European standard ČSN EN 17037 Daylighting of buildings has been valid in the Czech Republic since August 2019. A year and a half is enough time for the first evaluation of its functioning in project practice. The author of the article deals intensively with this practice and in this paper he would like to share some of his findings concerning the assessment of solar exposure of buildings according to this new European standard. On the edge of this problem, the relationship between accuracy and uniformity in normative requirements is also discussed.

© Fotolia.com
21.12.2020
Ing. Radim Smolka, Ph.D., Ing. Tomáš Petříček, Ph.D., Ing. et Petr Kacálek, Ing. Ph.D.

Panels for openings in structures have always been an essential and integral part of buildings. Their importance in terms of a building´s functionality was not recognised. However, the general view on this issue has changed from focusing on big planar segments and critical details to sub-elements of these structures. This does not only focus on the forms of connecting joints but also on the supporting systems that keep the panels in the right position and ensure they function properly. One of the most strained segments is the threshold structure, especially the entrance door threshold structure. It is the part where substantial defects in construction occur in terms of waterproofing, as well as in the static, thermal and technical functions thereof. In conventional buildings, this problem is solved by pulling the floor structure under the entrance door structure and subsequently covering it with waterproofing material. This system cannot work effectively over the long term so local defects occur. A proposal is put forward to solve this problem by installing a sub-threshold door coupler made of composite materials. The coupler is designed so that its variability complies with the required parameters for most door structures on the European market.


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