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The aim and purpose of the research are to analyze the performance of the technical supervision of the investor within the Czech construction industry during the construction, particularly focused on transport line structures. It is about clarifying the meaning and role of technical supervision in the public sector in transportation structures. In the first phase, a literature search is carried out on the current state of performance of the technical survey, and its work content is determined, including the method of its evaluation within the framework of a public contract. On the basis of these conclusions, a questionnaire is designed, which determines the real time-consuming activities during the performance of supervision and, at the same time, examines the tools used in its performance. Conclusions from the questionnaire research are examined, and steps for possible streamlining are proposed. As part of the examination of the proper evaluation of performance, a more suitable model of evaluation of these services is sought based on the previous analysis of the time-consuming nature of the technical supervision activity and according to the existing evaluation methods. Doi: 10.28991/CEJ-2023-09-03-013 Full Text: PDF

The article is devoted to the development of vacuum insulation materials using non-traditional core materials based on natural or waste polymeric fibers. This article describes the results of research activities on this issue where test samples of insulation from primary or recycled cotton and polyester fibers obtained from textile recycling were tested. The objective was to verify the properties of the developed insulators under extremely low pressure and thus the possibilities of their potential use as core insulators in the vacuum insulating panels. On the basis of the results found on both core materials and prepared vacuum insulating panels, it can be stated that core materials based on primary and recycled polyester fibers represent a great promise for the future. By reducing the pressure in the structure of these insulators, thermal conductivity is reduced to the level typical of high-quality conventional core insulators (e.g. based on glass wool). These materials exhibited very good thermal insulation behaviour depending on pressure and time at same level as insulators based on glass wool.

Construction and demolition waste makes up a substantial part of all waste produced in Europe. Its impact on the environment may be relatively small, but it exists in large amounts and holds many options of re-use. This is why it remains a frequently discussed topic of European policy. As part of circular economy, the European Commission has already proposed new goals and strategies for existing types of waste. However, they are not entirely clear on the usage of new kinds of building and demolition waste, as they are yet to be specified by existing legislation. This paper discusses new kinds of building and demolition waste and the basic principles (new technology) of their use. The possibilities of utilizing new kinds of waste are based on a multicriteria optimization calculation, specifying each material and proposing ways of its further use. Recent findings can expand the choice of new uses of construction and demolition waste and reduce their impact on the environment (less waste, better properties and more effective processing, reducing transportation needs, maximizing re-use and recycling). Stavební a demoliční odpad tvoří podstatnou část veškerého odpadu vyprodukovaného v Evropě. Jeho dopad na životní prostředí může být relativně malý, existuje však ve velkém množství a existuje mnoho možností jeho opakovaného použití. Proto zůstává často diskutovaným tématem evropské politiky. V rámci oběhového hospodářství již Evropská komise navrhla nové cíle a strategie pro stávající druhy odpadů. Možnosti využití nových druhů stavebního a demoličního odpadu však není zcela jasné, protože nesjou zatím stanoveny stávajícími právními předpisy. Tato práce pojednává o nových druzích stavebního a demoličního odpadu a základních principech (nové technologie) jejich využití. Možnosti využití nových druhů odpadu jsou založeny na multikriteriálním optimalizačním výpočtu, v rámci keterého se specifikuje každý odpadní materiál a navrhují se způsoby jeho dalšího využití. Nedávná zjištění mohou rozšířit výběr nových využití stavebních a demoličních odpadů a snížit jejich dopad na životní prostředí (méně odpadu, lepší vlastnosti a efektivnější zpracování, snížení přepravních potřeb, maximalizace opětovného použití a recyklace).

Dealing with waste materials, particularly hazardous waste, is a serious problem. Disposal areas keep growing, and the costs incurred are high. Disposing of such waste reduces negative environmental impacts and offers considerable financial savings. This paper focuses on the possibilities of incorporating pollutants found in hazardous wastes as fillers in coatings based on polymers (epoxide and polyurethane). These coatings are intended mainly for concrete and metal bases and offer secondary protection against adverse weather conditions. Important physical and mechanical properties of the newly developed materials were determined, they include surface hardness, impact resistance, tensile properties, and chemical resistance. These properties were also compared to those of the reference filler. At the same time, the influence of aggressive media on the properties of these materials was observed, in particular on flexural characteristics. The microstructures of the developed coatings were tested using a high-resolution optical microscope, before and after exposure to the chemicals. The positive effect of using progressive fillers, such as solidified hazardous waste (a solidification product (SF)), was witnessed by their constructive contribution to the materials&rsquo, physical and mechanical properties. The use of solidification products is unambiguously advantageous from technical, ecological, and economical stand points (utilization of hazardous waste as a progressive filler instead of landfilling, improvement of tensile properties, reduction in the price of coating system, and incorporation of the pollutants into the polymer matrix).

The aim of this chapter is to introduce a possible solution to water freight transport in the Czech Republic. In the beginning, the transport trends in freight transport have been outlined, the advantages and disadvantages of the national water transport have been described, the commodities suitable for water transport have been mapped, and the actual demand for water transport has been estimated. Next part discusses possibilities of evaluation of the economic efficiency of waterway projects by CBA method. Various approaches to the creation of financial and economic cash flows, based on which the investment project is decided, have been described. Finally, other related benefits and losses that are not considered by current methodological approaches, however, which can generate significant cash flow items for the calculation of efficiency indicators, have been discussed.