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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...

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...

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 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...

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...

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...

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...

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 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...

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...

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...

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...

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...

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...

The paper presents the technology of controlling a beam made of the Polytech material. The innovative Polytech technology was used to construct buildings made from prefabricated units. The Polytech system requires analyses and verification of the detailed data related to the strength and deformability of the elements used for building construction. A control technology was suggested that involved installation of a fiber Bragg grating deformation sensor on the surface of the investigated beam. Thanks to properly de...

In work results of researches of the heat-generating flameless heaters on the basis of not extinguished lime (calcium oxide) with addition of active and inert components in relation to a warming up of canned meat products in interaction with water are presented. The optimum ratios of components of the heat-generating heater providing the maximum heat release in interaction with water are established. For packing of tinned meat products in an aluminum jar and retorts packages in contact with the heat-generating hea...

The article presents an analysis of the impact of wind speed on the temperature changes in the external three-layer partition of a green building during winter period. Data for analysis were taken from temperature sensors located in individual layers of the partition and from a weather station on the roof of a smart building. The analysis period was January 2015. The purpose of the analysis was to determine the correlation between the wind speed and the temperature inside the partition. In the analysis period of o...

This article discusses the use of a 3D printer as a complex machine enabling not only 3D printing but also laser engraving and cutting. With a suitable design, the print head can be easily replaced with an engraving head [1]. With regard to the laser power, wood materials can be engraved or marked, and with the use of a chemical-based agent for engraving, we can apply it also to metals. A sufficiently powerful laser can cut even thin veneer, which can be used to create templates, stencils, models and graphical ite...

In cement production waste of various industries (metallurgical, chemical, etc.) is widely used. This contributes to the improvement of environmental protection and intensification of the clinker firing process, as well as improving the quality of clinker by modifying clinker minerals. Due to the large variety of wastes, the decision to use them effectively in the production of Portland cement clinker should be based on the results of scientific research both in the laboratory and in the industrial environment.The...

Volatile organic compounds (VOCs) play an important role in the IAQ evaluation process. Chemical contaminants emitted by dry building material and indoor equipment influence long-term indoor air quality. VOCs adversely affect both occupant comfort, productivity and health. Most of the health hazards related to VOCs emissions occur during the first months of occupation or after refurbishing the building. At present, most people generally spend up to 90% of their daily time in the indoor environment. Humans spend al...

The reduction of carbon dioxide emissions become the global effort of entire scientific community. Various environmental friendly technologies are currently developed and also applied worldwide. The concrete is the most used building material on Earth and its production is still rising. Its production is related to huge emissions of carbon dioxide due to Portland cement production and generation of waste such as concrete slurry waste (CSW). Sedimented CSW contains considerable amount of cement, calcium and fine fi...

Natural hydraulic lime (NHL) belongs to traditional binders used in civil engineering for centuries. Hydraulic lime (both natural or artificial) may be considered as binder which properties represents a transition between air lime (pure CaO or Ca(OH)2) and Portland cement (PC). It means that NHL contains hydraulic compounds (as PC) and CaO/Ca(OH)2. The significant difference is in calcination temperature ? NHL is calcined at lower temperature than Portland clinker i.e. there is lower energy consumption (and carbon...