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Lately, the focus is on equipping the constructions with sensors for monitoring deformations and displacements, the most common measurement systems are arrays of accelerometers. Recent literature focuses on wireless and mobile technologies for transmitting data from such sensors, combining several systems and measurement methods. This paper analize the possibility of using the interferometric radar tehnology to determine the vibrations and deformations of works of art especially bridges. Terrestrial radar interfer...

The determination of bitumen dosages for asphalt mixtures using empirical or semi-empirical methods (the specific surface method being the most well-known) no longer meets national or international technical standards. Most countries require the use of methods for determining the optimum binder content by laboratory tests grouped, usually, on several levels according to the Marshall or Superpave mix design. Romanian technical standards in this field are European and national standards, which unequivocally impose w...

This article is focused on the issue of lightweighted plasters. Lightweighted plaster can contribute to the contemporary tendencies of higher thermal insulating abilities of all structural materials with sufficient mechanical characteristics. Two mixtures were designed with the lightweight expanded perlite aggregate. The first one contained only expanded perlite as aggregate, whereas in the second one, the plaster silica sand was used instead of one-half of the lightweight aggregate. Lime-based components with adm...

Presented in the article common forms of so called underspace (space under bridges, viaducts or flyovers) revival show that there are organizational and design solutions, thanks to which these kind of areas can be transformed to some extent in order to improve not only their functional program or esthetics, but also their specific and disadvantageous environmental conditions. In the article there are presented results of research concerning available and practically applied solutions within architectural and plann...

The original archaic buildings were not protected in any way from adverse external influences, resulting in degradation of structures and often the subsequent destruction of the entire building. People tried to protect the buildings and this led to that they invented plaster. The plaster, as a unique product of human activity, complements the surface of the building and impresses with its final appearance and often raises the aesthetic value of the whole building. Plasters are conditioned in the course of history ...

Self-compacting concrete (SCC) represents a high fluid homogeneous mixture, able to fill perfectly the formwork without any external mechanical action due to the flow capacity under its own weigh. The productions of SCC demands new mix design procedure, with different constituent dosage using similar components as vibrated concrete. It contains a larger amount of powder, which allows the use of industrial by-products such as limestone filler, fly ash, ground granulated blast-furnace slag, silica fumes and others. ...

Gypsum paste was subjected to the temperatures up to 1000 В°C and its microstructure was investigated by SEM microscopy. The volume and mass changes were also measured and the bulk density, porosity and residual strength were determined. After heating to the 1000 В°C the structure of paste changed substantially, as can be seen in the micrographs. The structure of heated material is denser and the anhydrite crystals are bigger. The volume of the samples decreased more than 50%. The bulk density increased by 20%, wh...

This paper deals with new trends in fire testing of electrical cables. At present, the most widely used tests of electrical cables are reaction to fire tests. The cable systems powering electrical devices which have to remain operational for a certain period of time under fire conditions are additionally subjected to circuit integrity maintenance testing. New trends in cable fire tests include tests of critical heat flux, testing the effect of cable inclination, current load, voltage and frequencies to the rate of...

Due to EU environmental legislation focused on the reduction of waste, all post-consumer tyres must be reused, retreated or recycled. Rubber derived from post-consumer tyres is utilised in a number of engineering applications, however the market solutions for steel components are still not discovered. The main objective of the research was to develop the method of the valuable steel tyre cord application in the construction sector. Studies were conducted on recycled fibres modified concrete properties to examine t...

Magnesium oxychloride (MOC) cement, also called Sorel cement is a type of non-hydraulic cement, formed by mixing magnesium oxide powder with magnesium chloride solution. It was developed in 1867, shortly after the invention of Portland cement. MOC cement has many properties superior to Portland cement including lower carbon emission, lower thermal conductivity, higher fire resistance and excellent bonding ability to a wide range of fillers. For these advantages, MOC cement has been conventionally used for making f...

Nowadays, traditional residential houses are not built anymore, with few exceptions, although they represent valuable assets from the heritage point of view and also an important part in our cultural identity. In addition, they can be regarded as a seismically resilient typology and also as a cheap construction due to the use of local materials and especially of self-workmanship. The construction details of traditional houses used to be done very carefully, but this habit got lost with time. In recent years, due t...

In Romania, most of the construction and demolition wastes are stored together with other categories of waste or industrial by-products. Landfilling takes large areas of valuable land, but also causes air, water, and soil pollution, increasing the importance of any valorization or recycling technology for these types of materials. The European strategy regarding recycling concerns prevention, reuse and recycling of waste. The main materials that can be recovered from construction and demolition waste are: excavate...

The purpose of this paper is to identify key factors of social enterprises towards green economy development, specifically in Kosovo?s green business field. It considers a new field of research which relates entrepreneurship in general and specifically addresses social enterprises/social enterprises as a new component of doing business in green economy field. Through this paper, research questions are related to the role that social enterprises play in economic development in Kosovo. The paper is built on the hypo...

In southern Algeria, energy consumption is inevitable due to the hot climate and the summer period, which extends for more than half a year, it is necessary to take a strategic approach to ensure the sustainability and maximum comfort while reducing energy through passive and active architectural. Forthis reason, to reduce this consumption, it is necessary to improve the performance of the building. As a result, windows and ventilation become key points to improve in terms of Losses. These two elements may be at t...

Renewable raw materials, including natural fiber 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 required functionality. Noise reduction is a significant component in creating a professional and suitable work environment as open-plan offices have become a quintessential trend of the 21st century. The most common solutions in noise control include installation of noise ab...

The purpose of this paper is to study some mix design on different mortar mixtures whose results aim at obtaining high mechanical strengths, especially for flexural strength, with low water absorption, to prevent material degradation due to the action of various environmental factors and also to ensure their durability. From the category of cement additions widely used in the current practice due to their pozzolanic and hydraulic activity in latent condition, we refer to silica fume (SF) which is a mineral additio...

The parametric study carried out focuses on the impact of the type of glazing and its layout on the interior temperatures of a habitat. Different thicknesses, orientations and even different colors have been taken into account. The procedure for calculating the main parameters for the simulation and which correspond to each type of glazing is done via WINDOW7.3. Several simulations have been carried out for each case by EnergyPlus (dynamic simulation program of the building). Through the results of the simulation,...

The use of secondary resources and waste is the most important source of expanding the raw material base in the production of various building materials. Nowadays, there is an increased interest in technogenic industrial waste containing aluminum oxide, and in combination with technogenic materials containing sulfates, there is an increased interest, because their use makes it possible to obtain sulfoaluminate cements. The use of technogenic materials requires the carrying out of survey works both for the developm...

Correctly planning and designing are first steps and key aspects to achieve sustainable development, economic, social and environmental. Sustainable construction brings required performance on economic, social and cultural improvement. Sustainability in construction industry has more point of view. Building Information Modelling presents tool which meets the information requirement for sustainability design. Building Information Modelling (BIM) is one of the most progressive technology in construction field. BIM t...

Industrial sectors, including the building sector, started to recognize the impact of their activities on the environment in the 1990s. Significant changes were needed to mitigate the environmental impact of building sector. One option to reduce these negative effects is sustainable construction approach, which is starting already sustainable design of construction. Sustainable design of construction includes social, economic, and environmental indicators of construction projects. Waste management presents signifi...

This paper presents a joint research program conducted by the scientific contribution of Amirkabir University of Technology (Tehran Polytechnic) and the Technical University of Cluj-Napoca Romania aiming at developing sustainable Self-Consolidating Concrete (SCC) mixtures for using in concrete New Jersey barriers. The research program included an assessment on the fresh and hardened properties of: C25/30, C35/45, C40/50, and C50/60 strength classes of concrete mixtures to be used in the prefabrication of concrete ...

Ethanol dehydrogenation is commonly used as a process of production valuable products: acetaldehyde - the starting material for the synthesis of a large number of industrial chemicals such as acetic acid, acetate esters and hydrogen - attractive product for renewable energy. It is important also that alcohols produced from biomass (bio alcohols) can be considered as a renewable raw material. The purpose of this study was to elucidate the effect of composition and synthesis method of Al-Zr-Ce-complex oxides with 5%...

This study focused on the synthesis and characterization of L-proline polymer composite that will be tested for mild steel corrosion protection. Poly(butylene succinate) extended with 1,6-diisocyanatihexane (PBS) and L-proline were utilized to the synthesis of poly(butylene succinate)-L-proline composite. Solution polymerization was used as the method to get the amorphous water soluble polymer composite; and was characterized by FTIR, XRD and SEM. SEM-EDX of the polymerized composites was performed and the % count...

Applying sustainable development principles interferes with various spheres of human life. The greatest attention is paid to housing, transport, health protection, pollution, etc., i.e. areas noticeable by ordinary residents. Less emphasis is placed on the area of sustainable technical infrastructure. Minimum attention is paid to maintenance, operation, and repairs; and we may in this case often experience emergency maintenance only. Most operators and owners of the technical equipment have recently reported incre...

The paper describes a technology of controlling a prefabricated wall made of new material called Polytech used to produce prefabricated units. Prefabricated units made from a modified Polytech mortar based on expanded polystyrene derived from recycling were used to build a single-family residential building. Prefabricated elements are provided as wall panels. In order to control the prefabricated wall under realistic conditions, an innovative control technology was suggested that involved installation of a fiber B...

The paper describes technology of monitoring a joist slab used in a single-family residential building constructed in the Polytech system. Prefabricated units made from a modified mortar based on expanded polystyrene derived from recycling were used to manufacture building walls. The joist slab is based on prefabricated walls, by means of a reinforced concrete tie beam. In order to control the tie beam under realistic conditions, a monitoring technology was suggested that involved introducing fiber Bragg gratings ...

The paper shows selected results of the analysis of the number of people changes including periodical and long lasting staying of people at the room and the heat zones forming in some types of large-volume buildings. The possibilities of the use of those results in the green building design are considered.It is based on the research performed in the large-volume buildings, especially residential and sacral buildings. Here are some calculations of the changes of the people staying inside the building and its influe...

In the recent years, sustainable construction is increasingly popular, especially in terms of ecology and the inner climate. 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 analyzed professional literature indicates that the costs borne by potential tenants, the owners of the buildings and the society as a whole, caused by adverse inner environment con...

Daylight controls our natural biorhythm, influences our mood, has an important effect on how we feel and has an essential role in creating a healthy workplace. In most cases, daylight is not enough for reach the levels of illumination appropriate to the normal operation and we use artificial light. Incorrect lighting affects people's comfort, can lead to physical fatigue (especially eye fatigue) and reduced intellectual performance, especially when high concentration is needed. The implementation of lighting syste...

This paper focuses on a study regarding the use of waste in constructions: such as blast furnace slag from ironworks, as a by-product of the iron oxide reduction reactions by carbon monoxide resulting from coke burning. The slag is used in cement-based mortar mixtures under two forms: as granulated and ground slag powder under 63 ?m and non-granulated slag as an 0/4 mm aggregate resulting from solid slag, processed in crushing equipment and then sorted according to the standards on mortar and concrete aggregates. ...

Nowadays, raised awareness about the importance of sustainability and also the environmental impact of using concrete in the construction industry has led to numerous studies on how to create an environmental friendly material, with self-cleaning properties and how to possibly use it in urban areas and to ensure a cleaner environment and reduce maintenance costs. Nitrogen oxide (NOx) is the air pollutant which is directly responsible for the air pollution due to smog, smoke, vehicle emission, etc. The self cleanin...

The content of paper is theoretical case study of family house where the impact of night pre-cooling on operative temperature is analysed. The living space under pitched roof was selected for case study purposes. There are compared two types of building constructions. On the one hand side there is the wooden lightweight construction and on the other hand side there is the heavyweight construction made of reinforced concrete. The mechanical ventilation system provides for the required air change rate in living spac...

Sustainable Development Strategy is a policy established for the purpose of environmental protection. The strategy includes several policies which can be applied to designing, construction or building materials. The idea of performance concept states that one should optimize the amount of waste products in building materials. Such materials should meet all the requirements and standards, simultaneously being innovative and cost efficient. Waste products, acquire from various industrial process, must be properly di...

A new trend in concrete technology is to introduce photocatalytic concrete, also known as a self-cleaning concrete. This technology is based on the addition of TiO2 (titanium dioxide) to concrete mixes. Photocatalytic activity of TiO2 and its hydrophilic properties make it suitable for addition to building materials, particularly in architectural concrete or self-consolidating concrete. When concrete surface is exposed to the sunlight most pollutants are neutralized. In the present study the influence of addition ...

The plaster is one of the most often used materials in the civil engineering. It is applied in the form of plasterboards without any reinforcement, for example, cladding boards are unusable as supporting construction. To improve the mechanical properties of plasterboards, fibrous materials such as cellulose or glass fibre are added. The main purpose of the research is to clarify whether natural hemp fibres or straw could be used as the reinforced materials. The second purpose is to verify the use of non-standard t...

The ternary gypsum-based mortar, composed of gypsum, hydrated lime, silica fume, and standard sand was investigated. The system gypsum-lime- silica fume was prepared in order to improve the resistance of gypsum-based materials against water. The silica fume, as a pozzolan admixture, reacts with hydrated lime and forms CSH phases in the material. The method of storage has the influence on the development of material structure, its composition and properties. Therefore the samples were stored in two different enviro...

The performance of solar modules is fundamental during the conversion process in electrical energy, depending on the temperature of the solar cell. The photovoltaic power and efficiency decrease with temperature rise, Tc. In this paper are found useful aspects regarding the increase of the temperature of solar cells correlated with commercial photovoltaic panels, based on thermal monocrystalline silicon. Correlation of all parameters in terms of materials used by the photovoltaic industry, as well as weather condi...

This paper described results of the research in the field of organic based raw materials from the textile industry for the production of vacuum insulating panels (VIP) with extremely low thermal conductivity value. The paper presents current research findings on the behavior of fibrous structures on an organic basis at extremely low pressure. The practical findings and results of experimental work on the production and behavior of vacuum insulating panels with an alternative core insulant based on organic / natura...

In the production of metallurgical products, large amounts of waste are generated, which occupy significant areas and pollute the air, water and soil with toxic compounds. However, such wastes contain many valuable elements that can improve the operational properties of construction products, including lightweight cellular concrete, which will solve several problems at once: to free land, to improve the ecological situation in the area, to improve the quality of construction industry products. It is offered to use...

Concrete production is closely connected with large energy costs and even larger emission of greenhouse gases. An ecologically sustainable and responsible approach is being adopted with respect to waste minimization and application of alternative materials in building construction, to improve sustainability through energy efficiency, reducing CO2 emissions, the cost of building and life-cycle maintenance. This paper is aimed at evaluation of relation between deleterious processes caused by bacteria influence on co...

Computational modelling of hygrothermal performance of building materials has become very popular in recent decades as it is able to provide reliable results in a very short time. However, the accuracy of obtained results depends on various factors, the knowledge of material properties in particular. Even if many sophisticated experimental methods have been developed for that purpose, being able to provide reliable data, there is still one aspect which often remains ignored. According to the literature review, the...

In this paper we focused at the analysis of the possible use of biomass ash coming from wood chips combustion as pozzolanic admixture in mortar mix design. Biomass ash was characterized by XRF, SEM, and EDS analyses. The pozzolanic activity of the ash was tested using a modified Chapelle test. As the examined ash was pozzolana active, it was used as partial PC replacement in the composition of cement-based mortars. The PC replacing ratio was 10 and 15 wt. %. For the hardened mortar samples, bulk density, matrix de...

Woodworking hand tools have served as the basis for further development of the woodworking manufacturing. Even in nowadays woodworking hand tools are widely used in wood crafting. Besides they are used in manufacturing too, to complete some operations of wood technological processing without electrical hand tools and wood working machines. The aim of the research is to create structure scheme subdividing the woodworking cutting hand tools, which provides cutting as a main function of tool, in main and subgroups wi...