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The fundamentals challenges of shock loading impact are known as complex nonlinear problems with variable contact conditions. Even the simplified solution of these problems often bring in essential mathematical complexity related with: shock or elastic waves parameters, distribution of contact stresses, elasto-plastic deformation of the bodies in collision, balance and dissipation of energy, and others. Therefore, and in practice we often use simplified analytical approaches to resolve engineering challenges even ...

In construction field, concealed works are found in structural and nonstructural elements or may be component parts of them. These types of works have an importance role regarding the quality of the final construction, mainly due to their particularity with respect to difficult and complex methods of inspection, monitoring or intervention. There is a wide and complex range of concealed works in constructions, both in infrastructure and structure, as well as in architecture and resistance. All concealed works are c...

The article provides a comparative analysis of routing protocols in the context of use in wireless sensor networks with a MANET structure using for communication interaction of distributed facilities and engineering systems of buildings (such as automated dispatch control systems of distributed energy consumption objects, heating systems, cooling systems, building sensors and energy resources meters, etc.). As the most promising for further development, the protocols AODV, DSR, DSDV, OLSR with a description of the...

Photovoltaic technologies ensure the security and diversity of the energy supply without any negative impact on the environment, playing an important role in the production of electricity. At the moment photovoltaic systems oriented to energy performance have a relatively low efficiency, in contrast to the types and technologies of PV, but also the context of their use. The performance in terms of efficiency and long-term electricity generation depends on the current voltage parameters that differ depending on the...

The production of cavity blocks, also referred to as concrete masonry blocks (CMU) or concrete lost formwork, takes place in a mobile or stationary press by extruding a special matrix through solid fresh concrete. This production is relatively cheap, simple and fast, provided we have the appropriate press. This article examines whether such concrete blocks can be manufactured without specialized equipment. This can be beneficial, for example, in slums or areas dependent on humanitarian aid, where there is not enou...

When designing a passive house, the emphasis is not only on passive measures consisting mainly of thermal protection and stability of the buildings, but also on the price demand of each of the proposed structures. At present, new construction solutions are often encountered in construction practice [1]. These solutions are not yet tested. The paper deals with energy-efficient buildings in terms of reducing building heat loss. One such solution is to use thermal insulation above wooden rafters. Using the thermal in...

For energy-efficient houses, it is necessary to design a suitable thermal insulation of the building envelope. One of the most problematic areas of the single-layer masonry walls is the plinth. It is the first layer of masonry wall on the foundation structure. The requirements of architects and structural engineers for plinth solutions are often in contradiction. Passive houses belong to the category of buildings that have very low energy consumption for heating of buildings [1]. However, their overall energy perf...

This article is focused on the alkali activation of aluminosilicates prepared from industrial waste obtained from the final grinding of bricks during their production. The ceramic waste powder as a precursor with water glass-sodium hydroxide mixture as activator are utilized for the production of alkali-activated aluminosilicates, which represent a promising way for design of cement-free environmentally friendly binders. Usage of such materials in building industry for development of new materials have a very good...

Forming a harmonious color environment is an important aspect in creating comfortable living conditions in northern cities. Currently, there is a problem of using bark waste in woodworking and rubble waste during its processing. Thus, the use of these materials, including the creation of coatings and the formation of certain colors of city buildings, is relevant. This article presents a study of the color characteristics of dry blends and composites based on environmentally friendly raw materials. The purpose of t...

The paper shows the studies of methods for assessing of monetary and natural efficiency of energy-saving procedures in civil construction within comparative conditions. The groups of energy-saving procedures were identified by procedures for saving, procedures for losses reducing, procedures for resource consumption reducing. The factors that influence the assessment of energy-saving procedures are listed and the coefficients of comparable conditions in the assessment are justified. Methods for calculating the coe...

The ecological aspect of an office building can be observed mainly in the microclimate of its rooms. In the recent years, there is a growing interest in sustainable construction, especially in terms of the amount of fuel needed to heat buildings. This predominantly concerns commercial office buildings in which the achievement of an adequate standard and inner climate of rooms is often the most important criterion for the customer renting the premises. The costs borne by potential tenants, the owners of the buildin...

The article deals with the analysis of the possibility of observing body and clothes surface temperatures changes of large groups of people using thermography. Additional heat gains from people play a significant role in buildings where many people stay simultaneously. In those buildings, there is increased emission of heat from people, which has a significant impact on the microclimate of those buildings. This applies especially to sacral buildings, as well as other types of buildings where many people are inside...

The article deals with setting of the degradation of fibre-cement panels containing polyvinyl-alcohol (PVA) fibres. The degradation is being studied with a help of a soaking ? drying test. It is a long-time test, which is one of the series of tests (hot water test, frost resistance test, shrinking of panels, UV test), by which the degradation of panels is determined. The motivation for carrying out this test lies in searching for a substitute of asbestos-cement panels that cannot be used due to carcinogenic asbest...

Thermal insulating materials help to improve thermal protection of buildings and reduce their energy efficiency and greenhouse gasses production. Due to ever-tightening requirements in the field of energy efficiency of buildings, the consumption of these materials is increasing worldwide every year. From the point of view of sustainable development, it is necessary to look for technologies and materials that are based on renewable resources and are also energy efficient from the point of view of their production. ...

Measuring tools are one of the main tool groups, which subgroup, manual measuring tools play a decisive role for further development of the measuring tools and machinery for wood processing. Nowadays a wide range of these tools used in construction sites, workshops, studios, households and in manufacturing for quality control operations, measurement inspection and other. Depending on woodworks diversity and processing method, the manual measuring tools have various functions, shapes and uses. The diversity of tool...

Energy and raw material costs, an increase in environmental pollution, greenhouse gas emissions, global warming, depletion of fossil raw materials stimulate to seek and study alternatives to the synthetic fibres and products made of them for full or partial replacement. Renewable raw materials, including natural fibre sources, are the future of storage resources with a variety of positive effects on both the planet ecosystem and the living and working environment, and the energy consumption of delivering the requi...

According to studies, the construction sector is one of the biggest energy consuming and waste producing sectors in Europe. It faces the most pressing need to use advanced digital solutions for enabling eco-innovations to mitigate the environmental impact. For creating a favourable business environment by facilitating the use of state-of-the-art technologies that also are enabling eco-innovations, the Digital Business Ecosystem (DBE) should be developed. The aim of the research is to provide insight into the devel...

This paper presents some general directory lines regarding the development (design and effective production) of the cementitious composites with self-cleaning properties. Self-cleaning concrete represents a material containing nanomaterials, namely TiO2 nanoparticles with photocatalytic properties. Consequently, buildings facades made of a composite containing TiO2-SiO2, exhibit superhydrophilic effect on the surfaces, i.e., in the presence of UV radiation, the water reaching these surfaces have the ability to for...

The crack propagation and autogenous shrinkage pose a significant weakness for concrete structures. On this account, the utilization of smart materials can be viewed as a promising step to overbridge the common issues. Namely, the application of superabsorbent polymers (SAPs) can improve the autogenous shrinkage and crack sealing thanks to its great swelling capability. However, SAP particles used as water retaining admixtures have a substantial influence on the rheological properties due to fast water removal fro...

Cement-based composites belong to the most frequently used construction materials in the world which is mainly for their good mechanical properties and durability. However, production of cement exhibits significant impact on environment due to a high amount of consumed energy and CO2 emissions. Therefore, alternative environmental-friendly construction materials with comparable materials properties are currently intensively studied. Geopolymers based on alkali activation of waste precursors exhibit lower impact on...

Dismantling of dilapidated buildings in a huge modern megapolis like Moscow is one of the highest priorities and topical issues of our time. At current levels of renovation in the city a huge amount of build wastes is generated every year. A large part of wastes is reinforcement concrete and concrete waste. Recycling of these materials is a significant environmental aspect. Unsuitable concrete and prefabricated concrete elements are disposed of in landfills and thereby pollute the environment. At present millions ...

Bolted joints are a popular and relatively widespread method of joining wood-based materials in details not only of flat roofs. However, in some types of materials used to create structural details of flat roofs (for example, the above-mentioned wood-based materials), corrosion environments for bolted joints can be created in conjunction with increased humidity. The aim of this work was to verify the bearing capacity of bolted joints in various base materials (OSB board, birch waterproof wooden plywood and poplar ...

The paper presents some experimental study about fatigue properties modifications in Ni-Ti alloys on heating. The shape memory of alloys is used many times by heating and cooling and/or loading and unloading. The stability of material characteristics as transformation temperatures and mechanical behavior, during thermal or stress cycling is an important consideration in developing suitable alloys. Although shape memory alloys can be subjected to both thermal and stress cycling, it is necessary to investigate these...

The experimental research studied the possibility to develop an innovative coating type having a finishing and also a thermal isolating function, starting from three materials different as nature and presentation forms: kaolin powder ? a natural nanocompound, perlite granules ? a natural traditional thermal isolating material and an acrylic coating in aqueous dispersion with ceramic microspheres ? a modern synthetic thermal isolation nanoproduct. Three recipes of the new product type were made aiming to obtain hom...

Although the theme has been studied for more than a decade, the green transformations of buildings are limited in practice and often new buildings, by large private or public estates, promoted and publicized it to gain public support. Is it possible to think about a widespread action to ?green? our cities? If in other European countries the responsive-ness to this issue is certainly greater, in Italy there is still too little attention on this topic (in facts some people seem to be still more focused on economic e...

This paper deals with validation of an enhanced mathematical model for description of coupled heat and moisture transport which is able to model ice forming processes. This phenomenon is usually neglected because of computational difficulties even if it has a significant influence on heat and moisture transport. For the sake of model validation, data gathered by means of semi-scale experiment was used, analyzing a hygrothermal performance of a real building assembly ? an external wall. The wall was exposed to dyna...

The ambient temperature inside a building is essential for occupant comfort, and it influences directly the interior microclimate. Keeping the inner temperature at an optimum value involves energy consumption for heating and cooling. Energy consumption can be reduced by integrating phase change materials into the structure of the building. In thermal regime, with the integration of phase change materials, an integration model based on a mathematical method suitable for a thermal process analysis is described. This...

The paper presents the studies of an improvement of techniques for energy saving management on the principle of sustainable development. The authors proposed a hypothesis for the sociocultural, environmental and economic aspects of the sustainable development principles and their correlation with the management of energy-saving procedures in civil construction. Qualitative and quantitative efficiency from improving techniques of energy-saving managing are highlighted. The baselines of the energy consumption are id...

Magnesium potassium phosphate cement (MKPC) is a chemically bonded cementitious binder prepared by mixing dead burned magnesia powder with KH2PO4 and water. Comparing with conventional Portland cements, MKPCs exhibit some advantageous parameters as low dry shrinkage and high early compressive strengths that predestine them mainly for rapid repair of infrastructure. To reduce the heat evolution and cost related to the use of this type of cement, MKPC was blended with 30-50 % by mass of biomass ash. Dead burned magn...

Influence of different type of mould-release agent on surface properties of coloured concrete is presented in this paper. The quality of exposed concrete areas is directly affected by several factors. In addition to the most important factor, which is the influence of the outdoor environment, has the inconsiderable influence on surface properties of concrete manufacturing technology and the used material. This article is focus on roughness and colour intensity of concrete elements. Concrete samples were created in...

In summer, building interiors are often overheated. It is common situation especially for buildings with structures from lightweight materials (e.g. attic rooms). One of the ways to solve the excess heat removal from the interior during the summer months is integration of some phase change material (PCM) into building structures. PCMs are capable of storage latent heat at normal indoor air temperatures. In this paper, a comparison of thermal stability in two geometrically identical attic rooms is made. The differe...

Electrical cables are one of the key components of green building technologies. They are crucial for the operating of many green building technologies (e.g. power transfer from the solar cell to other building electric devices). For fire safety level assessment of electrical cables installed in green buildings are used their fire characteristics. The reaction to fire is the fundamental and most important fire characteristic of electrical cables. Nevertheless, it is used almost exclusively in the prescriptive appro...

Biomass combustion represents a renewable energy source and helps to reduce carbon emission. As the amount of solid residuals from biomass combustion will increase in a near future, the newly designed lime-based plaster modified with pozzolana active biomass ash was studied in this paper. Reference lime plaster and plaster with 15% binder replacement by mass with wood chips ash (WCHA) were the subject of an extensive experimental campaign. As there was a reduction in mechanical parameters for plaster with incorpor...

Many members of steel structures are subjected mostly to bending. In these members from the economical point of view is very useful to utilize also plasticity of structural steels. The elastic-plastic resistance of steel members subjected largely to bending depends in large measure on local stability of their compressed flanges and bending webs in decided cross-sections and areas. The real elastic-plastic behavior of the steel members and their bending webs and compressed flanges is complicated. Therefore, the rep...

The evaluation of the catalog parameters of the voltage, the current of a PV module is essential in the design and implementation of photovoltaic systems, the reference parameters differ depending on the temperature of the operating cells and the different levels of radiation. The analytical methodology was the basis for creating a characteristic model for modeling a cell or a photovoltaic module in Matlab/ Simulink, using cell data at STC, considering standard global radiation G = 1000 W/ m2, the operating temper...

Concrete is a widely used construction material. Extraction and processing of raw materials used for its production requires a lot of energy and poses threats to the environment. At present, in accordance to the idea of sustainable development and close circuit economy, it is recommended to aim at the maximum reduction of raw materials by replacing primary materials with secondary raw material (recycled materials) or industrial by-products. One of the pro-ecologic attitudes is introducing secondary wastes from the...

The article addresses the problem of such a common phenomenon as dysbacteriosis, according to medical experts in Kazakhstan, up to 90% of citizens are susceptible to disruption of the intestinal microflora. It was mainly influenced by the economic crisis of recent years, as well as environmental problems that adversely affected the nutritional structure of the population. One of the way to solve this issue is the use of probiotics, contributing to the normalization of the intestinal microflora to have a regulating...

This paper aims to provide an overview of the technologies of passive heating and cooling by using phase change materials, integrated in the interior elements of constructions, to ensure the energy efficiency and the reduction of carbon dioxide emissions from buildings, approaching in at the same time the new and existing buildings. Considering that ensuring the internal thermal comfort of the occupants requires high energy consumption, the use of phase change materials by creating a passive energy storage system ...

In construction are still mostly used materials with a negative impact to environment. Extraction of stocks natural resources is limited and the energy intensity of their processing is very high. Composites based on alkaline activation could be a partial alternative of these materials. These composites, based on alkali-activation of secondary products of metallurgical and energy industry achieve higher strengths then currently used binders and are also characterized by higher resistance. The paper deals with the p...

The production of red-clay hollow bricks belongs to the sources of industrial waste which gained on importance during the last decades. Although the amount of scrap is similar to the traditional red-clay bricks, the total waste generation is higher. As the current technologies of hollow brick production do not make it possible to provide sufficiently smooth and even surfaces, the brick blocks have to be ground after leaving the production line. This grinding generates a significant amount of waste powder containin...

Today the use of biomass combustion for the generation electric power is enormously growing. It is due to the worldwide interest in the environmental sustainability and production of renewable energy. With increasing amount of biomass combusted for energy supply, huge quantity of biomass ash is generated worldwide. One of the open questions related to extensive biomass combustion is what we are going to do with this huge amount of biomass ash. Considering both the environmental and economic issues, biomass ash mus...

In the struggle between graphic and electronic communication taking place in our evolving information society, this latter type of communications seems to have a more positive image in society. Such judgment must have emerged as a result of opinions that have been formulated in relation to the erroneously interpreted and assumed environmentally-damaging impacts of printed products and technologies. The author proposes to create an EEFP confirmation label and develop a rating system. Taking into the account the alr...

Concrete is one of the most important and useful materials in the construction sector, which, unfortunately, has an adverse impact on the environment. It is evident that correct procedures for designing concrete structures need to be created. The sustainability approach is a key conceptual principle to be considered in cement and concrete production all around the world because about 7 % of global CO2 emissions are produced by cement manufacturing. An indicator expressing quality, with regard to sustainability, is...

Construction and subsequent operation of buildings fall among the main consumers of material and energy resources, while contributing to environmental pollution. Sustainable building construction therefore responds to the requirements of sustainable development and introduces a new approach to the design, construction and operation of buildings with the aim to reduce negative impacts on operating costs and thus on the environment. Operating costs generally represent the sum of the costs incurred for the operation ...

Article is describing results of an experimental program focused on development of concrete, resistant to impacts of low pH environment. To a very low pH (2-4) is concrete often exposed when used in agricultural production (for example for silage or hay silage pits). Therefore, its degradation with such a low pH is very fast. The experimental part of the work focused on modification of concrete with sealing admixture on the basis of styrene-acrylate. We prepared set of 3 concrete mixtures with different dosing of ...

The need of increasing the use of alternative materials, in construction and in production, is a current issue worldwide. At the same time, with regard to the treatment of waste, the management of bottom ash coming from Municipal Solid Waste Incineration, is an important issue all over the world, especially in Italy. In fact, the need for right management of ashes increases, which, in Italy, are almost always disposed of in landfills. This paper presents the environmental aspects of an industrial experiment, in Ce...

This paper presents the experimental results regarding the evolution into time of the road concrete quality with blast furnace slag BS, obtained by the UPV test for measuring the propagation velocity of the ultrasonic pulses compared with the compressive strengths of mechanical tests The UPV and the compressive strengths of the concrete containing blast furnace slag were determined at the age of 28, 100 and 150 days on 150 mm cubes on road concrete made with conventional materials and on road concrete with blast f...

Gypsum composites with different lightweight aggregates were studied. The importance of gypsum as one of the most environmentally friendly building binder increases nowadays and new ways of its utilization are searched. Using of aggregates in the gypsum is generally not necessary, because gypsum does not shrink, but they can be used for economic reasons or to improve the thermal or fire properties of the gypsum material. We studied the structure and properties of the gypsum composites with three types of lightweig...

In building materials, under reduced pressure, a significant improvement in thermal insulation properties occurs due to the elimination of conduction and flow through the gas phase filling the pore system of insulators (in case of the most insulators). This effect is used in the manufacture of vacuum insulating panels. In earlier times, vacuum insulating panels have only been produced with glass wool or SiO2 based insulators, but alternative insulating panels have also begun in recent years. These insulators are t...

Lighting Engineering Laboratory ? LEL - is the main lighting independent consultant around Transylvania (the north-west side of Romania). Over the past few years the Lighting Engineering Laboratory developed and implemented different trial energy efficient lighting solutions for the university buildings. The Building Services Faculty was used as a lighting test area. The starting point was in 2013 - the lighting refurbishment success of the greatest lecture hall by replacing the old 4*18 W fluorescent luminaires b...