Nejnavštěvovanější odborný web
pro stavebnictví a technická zařízení budov
estav.tvnový videoportál

Podlahy, příčky a povrchy
Archiv článků od 31.3.2013 do 20.10.2014

Archiv recenzovaných článků

zpět na aktuální články

Praha
20.10.2014
Ing. arch. Marek Janatka, Ph.D., Katedra urbanismu a územního plánování Fakulta stavební ČVUT v Praze

Prague building regulations currently represent debated and controversial topic among both professionals and the public. This is a new concept of law to which they are greatly implemented basic knowledge of urban theory and practice. The article summarizes the basic principles of the new regulation in the field of territorial requirements.

17.3.2014
Autor: Ing. Bohumil Koželouh, CSc., soudní znalec

An overview of the development and standard types of the prefabricated wooden houses, their basic structural materials, basic mechanical timber joints, design practice for loads effects and requirements for structural elements is presented in the five-part series. In the second part basic structural materials are dealt with.

10.3.2014
doc. Ing. Jiří Dohnálek, CSc., soudní znalec, autorizovaný inženýr a soudní znalec

The article draws attention to situations, which are created when cracks in concrete and reinforced concrete structures are evaluated. Despite cracks being in general allowable in reinforced concrete structures as per ČSN EN 1992-1-1, only the width of cracks must be limited with respect to functionality of the structure. These limits are well defined with respect to water impermeability of reinforced concrete structures or their durability, but we are missing criteria, which would allow for evaluation of influence of the cracks on visual appearance of the structures. Therefore very frequently situation arises, when cracks are not warranty claimed as a potential static defect or a flaw, or as an aspect influencing lifespan of the structure, but solely as an aesthetic defect.

3.3.2014
Ing. Petr Tůma, Ph.D., Betonconsult s.r.o.

The paper describes the basic division of surface protection systems for concrete, which define standard EN 1504-2. Evaluates various parameters prescribed in relation to the requirements of the usual structures and gives appropriate use of various systems. The following are examples of inspections carried out and assessed defects.

Stavba železobetonového skeletu s jeřábem
17.2.2014
Mgr. Mikuláš Vargic, Advokátní kancelář Šikola a partneři, člen konsorcia Frank Bold

New Civil Code enacts special type of solidary obligation to remedy the defects of building constructed under contract for works. All subcontractors (suppliers) of constructor, investor`s technical supervisors or construction project designer are solidary responsible together with the constructor in case the defect can be attributed to the performance they provided. However, these parties need not to be the parties to the contract for works itself (and usually are not) as their obligation arises by law.

The remedies that the investor can claim on these co-debtors, however, are limited to right to demand the repair of the defect. Investor may demand remedy on any of the co-debtors and all the co-debtors are obliged to perform the remedy in full.

The investor has to give notice to the debtor within a reasonable time. The notice can be sent to any of the co-debtors but we advise all investors to give notice always to the constructor first or together with the other co-debtors.

27.1.2014
Ing. Šárka Keprdová, doc. Ing. Jiří Bydžovský, Ph.D., Ing. Tomáš Melichar, Ph.D.

Cement-chip boards are construction elements which merge suitable wood and cement properties with the synergic effect designed for all-round use. The disadvantage of these boards remains the relatively high price. The price can be decreased by partially replacing initial raw materials. The paper addresses the option to modify the composition of cement-chip boards using alternative raw materials. Representatives of organic and inorganic materials were used (e.g., hemp, straw, waste products from production of mineral insulations and textile fibres). Alternative materials were used in the production of cement-chip boards under laboratory conditions in two various percentage ratios for the substitution of the wood component. In particular, 100 % and 50 % of wooden chips were replaced in the basic receipt of the boards. Testing bodies were produced using a mechanical press and basic properties were tested after 28 days of maturing. The results of individual board parameters – density, coefficient of elasticity and bending strength were compared with the normative requirements for cement-chip boards which are specified by standard EN 634-2.

13.1.2014
Ing. Jiří Nováček, Ph.D., Stavební fakulta, ČVUT v Praze

The comparison of different calculation methods for airborne and impact sound insulation between rooms is given in this paper. Theoretical influence of flanking transmission on total sound transmission between rooms is done, based on calculation results for reference set of residential buildings. New simplified methods are also introduced for estimation of corrections for flanking transmission in common cases.

23.12.2013
Mgr. Ing. Anna Francová, Mgr. Dana Stejskalová, Advokátní kancelář Šikola a partneři, člen konsorcia Frank Bold

The article describes the characteristics of claims for defects from contract for work according to the new Civil Code. The new Civil Code unifies the provisions on contract for work currently contained in both Civil and Commercial Code. The article describes the defects founding the liability of a contractor, reporting the defects and warranty, the rights resulting from the defects and the specifics of claims for defects when the subject of a contract is a building.
It is important for the work to be clearly specified in the contract. Differences from the contract are considered defects. It is vital to inspect the work after the handover for any differences from the contract. The ordering party has to report the defects to the contractor without undue delay. The statute of limitations for claiming the rights from defects is 2 years. The rights resulting from sales contract defects apply analogously to the contract for work. In case of substantial breach of contract the ordering party can ask for the delivery of a new work, repairs or resolution of a contract. Unsubstantial breach of contract allows for repairs or discount.
The last part of the article concerns specifics of claims for defects when the subject of a contract is a building. The ordering party cannot refuse to accept the building for minor defects. The statute of limitations for reporting hidden defects is 5 years in case of a building. The responsibility for defects in shared between the contractor, the maker of the documentation and the construction supervisor.

Inspektor nemovitosti
9.12.2013
Ing. David Sýkora, Katedra městského inženýrství a stavitelství, Fakulta stavební, VŠB-Technická univerzita Ostrava

The article deals with a new product in the Czech market that is quickly getting to awareness of potential clients and gaining a significant place in the local real-estate market. Until recently, the inspection of immovable properties was an unknown concept. Nevertheless, in recent two years such assistance service is being more and more popular. Pertinent specialised inspection companies assist the real property buyer in eliminating potential risks that are related to selection and purchase of a given building. A competent certified inspector checks up to about 200 items of the building and compiles an expert report to help the client to correctly decide whether he should buy the given building or not. The inspector will acquaint the client with a real purchase price, precisely describe all the defects and how to correct them, and finally, he will hand over to the client a complete budget to cover the cost of necessary repairs.
In 2013 the inspection of real properties comes to one of the fastest growing segments of Czech economy. The people intending to buy any real property are more cautious and, now at the time of an economic uncertainty, they begin using the above relatively new assistance service in a large extent.

25.11.2013
Doc. Ing. Jiří Dohnálek, CSc., Ing. Pavel Dohnálek, Ph.D.

The article describes the reasons for verification of moisture content of substrate layers and draws attention to illogicality of current approach, where moisture content in only very thin surface layer of 10 to 20 mm thickness is verified, but the influence of moisture held in entire thickness of the substrate layers is fully neglected. The article recommends use of in situ methods of measurement of dynamic moisture content of substrate layers, as it is for example described in American norms ASTM F1869-11 and ASTM D4263-83. Only moisture content measured by such methods, allows the contractors and investors to avoid many times fatal consequent failure of surface treatments.

Podlaha z PVC
18.11.2013
RNDr. Jindřich Petrlík, Mgr. Jiří Kristian

Recently, healthiness of the indoor space of buildings has been discussed more and more often. One of the points of view has been also presence of toxic substances, released into the indoor space from materials used for construction and design of the rooms, and from furniture. The most questionable materials include certain plastics, and, among them, especially polyvinyl chloride (PVC). Among other things, phthalates (used as plasticizers for PVC) may be released from this plastic. The Arnika Association commissioned analyses of 5 samples of floorings and 3 samples of wallpapers made of soft PVC. Phthalates were found in all the samples, in the range from 4.85 to 17.03 % of the product weight. In two of the samples, di-(2-ethylhexyl)phthalate (DEHP) was used as the plasticizer. DEHP will be banned in the European Union from 2015, together with 3 further phthalates. The remaining samples contained di-isononyl phthalate (DINP) and di-isodecyl phthalate (DIDP). These phthalates will not be banned, but they are also questionable from the point of view of health impacts. Four years ago, the Arnika Association took also samples of dust inside various buildings. Phthalates were found in all of them. The highest phthalate concentration was found in dust from a school dining room with flooring made of PVC. Presence of certain phthalates in dust is risky especially for young children. Phthalates are related to allergies (BBP, DEHP, and DINP) and asthma development (DEHP) in children.

18.11.2013
Ing. Bohdan Nešpor, Ing. Hynek Vilam

The purpose of this paper is to inform about research and development results of special composite materials with enhanced capacity to accumulate infrared radiation. The aim of this project was to create an adjustment for wall and ceiling surfaces enabling good conduction, absorption and storage of thermal radiation with subsequent slow release of heat energy stored during periods of intermittently heating. This proposed solution in conjunction with infrared heaters and air conditioning equipment provides sufficient thermal comfort in heated spaces during winter season and thermal stability of rooms in summer. The main emphasis was on cost saving and increased efficiency of heating systems and cooling units.
The article presents one possible solution and principle for increasing absorption of infrared radiation and accumulative ability. The emissivity and surface temperatures of the developed sample were measured within the frame of the experimental works on real laboratory models in cooperation with specialists from Brno University of Techology (BUT) in Faculty of Mechanical Engineering (FME) and Faculty of Civil Engineering (FCI). The analysis of thermal comfort and energy balances including the assessment of the suitability in summer and winter was performed as well.

24.6.2013
Ing. Jozef Bednár, TU Zvolen, Drevárska fakulta

The paper presented method of laboratory measurements for specifies air permeability of building board elements of wood- based. The aim of laboratory measurements was to designate value of air permeability of building board elements of wood- based. The results from measurement are in form protocols which indicate air permeability for differential pressure 50 Pa. The value air permeability decides about application and quality building board elements for airtight layer.

Změny v druhové skladbě českých lesů
3.6.2013
prof. Ing. Vilém Podrázský, CSc., prof. Ing. Jan Kouba, CSc., Ing. Daniel Zahradník, Ph.D., doc. Ing. Igor Štefančík, CSc.

Forestry and forest management plays many roles in the landscape and in the socio-economic area. Forests represent a landscape stabilizer, the best preserved part of the landscape of predominantly natural character with significant application of natural, spontaneous process. It also serves as a source of material benefits to human society. The wood-producing function of forests was questuioned in this country in recent years. Above all, leaders of various environmentalist movement are demanding ever greater proportion of forests without economic activity. However, forestry is afflicted by such influences by decades and the aim of this paper is to demonstrate possible implications of these trends for forestry and subsequent economic sectors.

Postup a výsledky kontroly optických prevažovacích prístrojov
13.5.2013
Ing. Ján Ježko, PhD., Katedra geodézie, Stavebná fakulta, STU v Bratislave

Setting out and control of a vertical direction belong among often solved tasks in civil engineering. In order to setting out a plumb line the optical plumbing instruments are used. The most commonly used instrument for this activity is Zeiss PZL (Zeiss Zenitholt PZL 100). This contribution describes the procedure and results of testing according to STN ISO 17123-7: 2010 Optics and optical instruments – Field procedures for testing geodetic and surveying instruments. Part 7: Optical plumbing instruments.

Základní charakteristiky modifikovaného dřevoplastového kompozitu
6.5.2013
Ing. Anna Benešová, Ing. Jan Vaněrek, Ph.D., prof. Ing. Rostislav Drochytka, CSc.

This article describes a modification of wood-polymer composite using waste and secondary raw materials. It also shows the anticipated tests that will be carried out on samples prepared by innovative technology to ensure accurate interpretation of results.

Teplotní dilatace obkladových desek
22.4.2013
prof. Mgr. Jan Toman, DrSc., Ing. Tomáš Korecký

The linear thermal expansion is thermal technical parameters that are important for the specific application of products site. The dilatometer was used on each given speciments of sizes 2 × 12 × thick, gradually increasing the temperature to 1000 °C and change in length was measured. From this was calculated coefficient α.

31.3.2013
Ing. Marie Bačáková, ITC Zín a.s., SGP-STANDARD

Information and access to technical standards plays very important role, when construction products are placed on the EU market. For the purpose of it can be very effective to use web of Czech office for standards, metrology and testing. Basic data for web are prepared by Institute for testing and certification. ČSN standard references placed in this web are connected with ÚNMZ web service „CSN on-line” and makes possible users of this service directly access to full texts.


zpět na aktuální články
 
 
Reklama