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The field of construction is considered as a priority in terms of influence on the environment. Attention of researchers is now focused on composite materials made from natural or recycled fillers with clay, cementious or polymerics matrices, among which the non-toxic and biodegradable - Eco-composites, are highlighted. These are attractive because they are safer and more environmentally friendly. Eco-composites are a special category of composite materials, using materials that have the least impact on the enviro...

The aim of this research is to analyse the thermal properties of different non-traditional insulation materials with low thermal conductivity and light weight that are made from Latvian local raw materials and are ?green? or are innovative and advanced materials. The studied materials are grouped depending on the production type and possible applications as follows: ? multi-layer combination of insulation materials, incl. low-emission surfaces; ? straw, cane, hemp, and birch wood fibreboard made from local raw mat...

Blast furnace slag (BFS) is used for preparation of common cements, sulfate-resisting and chemical-resisting cements and cement mortars. Using BFS as a concrete or mortar addition results in several advantageous properties such as high resistance to acid attack (sulphuric, nitric acids), low chloride permeability, high durability and low capillary porosity. Because of these properties using BFS in cement composites can decrease the effect of biodegradation induced by various microorganisms. Bio-corrosion is caused...

Porosity belongs to basic characteristics of building materials. It is a characteristic of solid or semi-rigid materials, which contain a lot of tiny and uniformly distributed cavities or holes of various shape and origin. Porosity decreases specific weight of materials, increases their insulation and other characteristics ? for example absorbability. It is defined as a ratio of pores volume in a specific amount of solid and the total volume of this amount. In the article the use of the modern confocal scanning mi...

Building is constantly heading for the development of new technologies, better materials and reduction of energy consumption, however daylighting remains an essential factor that considerably affects the interior of buildings and it cannot be technologically improved or replaced. The total quality of the indoor environment is crucial to humans. Daylight is important not only from a psychological and health point of view, but also from the point of health standards. People who are forced to work in workplaces witho...

Occupational health and safety is an important work discipline that must be included in the working life. Especially, developed countries have been able to place this discipline in working life, while developing countries have still problems. These problems take place both in terms of legislation and practice. The situation is similar to that of developing countries, in Turkey. The construction sector is in line with the development status of a country. The construction sector contributes both directly and indirec...

A particular importance in the behavior of asphalt mixture is given by the behavior of the mastic formed by the mixture of filler and bitumen. Depending on the type of filler, the mixture has a different behavior in taking over traffic loads and temperature variations. At the same time, an inappropriate dosage of this mixture may adversely affect the behavior of the asphalt mixture in operation. This paper presents the behavior of the MAS 16 stone asphalt mixture stabilized with different types of filler (limeston...

In the near future, all new buildings across European Union will have to meet the nearly Zero Energy Buildings requirements, namely to have a lower primary energy consumption and lower carbon dioxide emissions. In this regard, each country set its own targets concerning the reduction of these values. The paper presents a computational study regarding the thermal performances of an apartment, insulated in the first case scenario with a common solution such as expanded polystyrene and for the second and third case s...

All building materials contain more or less natural radioactivity. The recycling of waste by-products, nowadays, gaining more and more importance, research on that kind of materials is being carried out and such materials are utilized as additives in the production of special mortars in many countries. As radiation of terrestrial origin in buildings does not only originate from the soil, but also from the used building materials, a greater absorbed dose rate can be measured within buildings. EU technical guidance ...

In Romania, the European technical standards concerning the quality control of the primary materials and asphalt mixtures used in road and highway works have been harmonized. In the same time, Romanian norms were adopted. These norms set limits within which every characteristic must range, without the possibility of adopting other values, even if laboratory tests prove, in many cases, that the imposed limits do not correspond to the practical reality. Also, most Romanian road laboratories own automatic Marshall eq...

Coatings based on microspheres are internationally recognized for their heat insulation characteristics, due to the specific properties of their nanoparticles ? ceramic, glass, silicon microspheres - even when the layer thickness has only 1-2 millimetres. Taking into account the high price of such products, the research studied, through specific experimental laboratory works, the possibility of obtaining a new and cheaper heat insulating product, by introducing kaolin as a filler. The experimental results showed n...

One of the most important problems of the modern world is the pollution of the natural environment. Human activities associated with the development of various industries have a huge impact on the surrounding environment. Unfortunately, often this impact is negative and in many cases its effects are irreversible. Human activities strongly affect the environment by polluting the atmosphere, hydrosphere and lithosphere. Currently, the degradation of the natural environment that has been observed is due to the econom...

One of the most important questions to deal with while conducting a building development project is the selection of a variant investment solution. In a situation where we have several possibilities of performing the building processes, a choice must be made. And when there are many factors involved in a decision-making process, it is much more complicated to arrive at a decision than in a situation when an assessment is based on a single criterion. One of the elementary stages in a decision-making process is when...

The presented experimental work investigates the development of fire in a compartment made of cross laminated timber (CLT) panels and its impact on fire safety of cables. Impact of protective shielding provided by plasterboards compared to exposed panels thermally loaded by fire inside of a compartment was also examined. During the experiments a fire-technical properties were continually monitored, such as heat release rate, consumption of O2, CO, CO2, time to flash-over, time to termination of flames and temperat...

The paper deals with the possibilities of using textile waste in the form of synthetic and natural fibers for the production of thermal and acoustic materials. The paper presents the results of the research that confirm that the waste fiber insulators can show more favourable properties in some areas than conventional synthetic insulators commonly used in the building industry. The advantage of insulators from waste textile fibers is their high variability. In the field of them insulation properties, these insulat...

The paper presents studies on the development of multifunctional modified clay mineral-base additives that are used for paint, coating, resin and other finishing building material applications to improve the durability of the finishing products by protecting it from degradation processes as abrasive influence, UV radiation, moisture and microbial influence. Such swelling clay mineral as montmorillonite (smectite) is selected for the development of hydrophobic and UV protectable additive because of its specific phy...

Studies have been carried out to increase the activity of ashes and cements by separate or joint activation in an aqueous medium immediately before the preparation of concrete on the construction site. Activation was carried out in devices where the treated medium was subjected to hydrodynamic and cavitation effects. When using coarse-grained ash, it is possible to recommend either their preliminary grinding in an aqueous medium before adding into the concrete mixing unit, or joint activation with cement. The join...

At the global scale, the construction sector has a significant social and economic influence over people?s daily activities. At the same time, it is well known that the built environment is responsible for a significant negative influence over the Earth?s ecosystem. Taking into account the climate change phenomena registered nowadays, as well as the expected increase in the global volume of negative effects over the natural environment, considering the ecological dimension of sustainability in the construction sec...

As a rule, buildings make an impact on their surroundings. Industrial and manufacturing facilities obviously create the most severe problems. This is due to the technological processes involved, the need to ensure transportation routes to provide supplies and the necessity to handle waste products. Residential buildings are not normally considered in terms of being a threat to the environment, although their large agglomerations are likely to give rise to many problems and are not neutral to the environment. This ...

The topic of increased CO2 concentration is very actual in the Czech Republic, especially in the connection to the current effort for a massive revitalization of buildings, which aims to reduce the energy performance of buildings. Both residential and civil buildings revitalization includes predominantly replacement of windows and insulation by the contact system. Exchange of windows and high-quality contact insulation then result in almost no infiltration at all. So, when the forced ventilation is not compulsory ...

The paper presents an analysis of the behaviour of an air-water vapour compression heat pump at the variation of some of the decisional parameters as the state of the fluid at the compressor intake. Different refrigerants as CO2, NH3 and R600a, and different schematics are considered. The large use of rotary compressors in the industrial and domestic heat pump area has determined the investigation of the influence of the wet compression. The analysis is based on the exergy concept that enables to point out the loc...

Geopolymers are green and eco-friendly alternative to commonly used resins. Geopolymer are derived from the naturally occurring recyclable geological materials and combine low temperature, polymer-like processing with high temperature stability and fire resistibility without toxic smoke generation. The aim of this work is to manufacture geopolymer blades for an experimental axial fan, which is the first step on the way to produce full-fledged geopolymer blades. These blades could be then used for ventilators in ro...

The effective management of operating costs, processes and space utilization is one of the basic requirements of owners and possibly building operators. The effort is to optimize these costs in order to ensure the comfort and safety of the workers in the buildings while avoiding unnecessary waste of the basic operating media and the human workforce. This optimization deals with facility management, which can misinterpret different concepts in different countries of the world, as the facility management definition ...

The parking platforms required for the operation of different industrial, service, goods storing and manipulating companies, inside boarding houses, hotels, stores, gas stations, etc., are continuously and quickly developing, in close line with the development of economic activities and the construction field. The technical solutions applied to realize the resistance structures for these surfaces are very diverse and, in several cases, do not include a proper resistance calculation according to the traffic intensi...

Together with clay and rocks, wood represents the oldest building material, used for developing the overall infrastructure, namely civil structures, road and bridge elements. Its use as critical building material is still wide spread worldwide, due to intrinsic qualities of wood as building material and also due to its availability, being generously offered by nature. Romania, despite of huge lacks of legislation and practical protection of forests and wood as strategic resource, still has important, high quality,...

The construction sector is one of the largest consumers of energy and non-renewable natural resources, but also an important increasing factor of global warming by producing greenhouse gases, especially CO2. In Europe, about 30% of CO2 emissions and 36% of all greenhouse gases emissions are a direct or indirect environmental consequences of the construction sector. In the sustainable development contex, the possibility of recycling, reuse and reintegration in nature, environmental protection and efficient manageme...

A new joint configuration system has been developed to achieve a higher strength and ductility. The joint system consist of a reinforced concrete wall and a composite steel-concrete beam. The study aims for an experimental and a numerical part in a FEM program Abaqus 6.13. The program consist to reproduce the behavior of the joints and the materials variation. The purpose of the paper is to investigate the main parameters that affect the response on the contribution of the steel-concrete materials that influences ...

In the fire statistics, electrical appliances are one of the main sources of fire. In such fires, the first ignited component is the insulation around wires and cables. The aim of this paper is to determine the impact of isoperibolic heating (in the range of 200 ? 400 В°C and with a heat gradient of 10 K in 10 min) on fire resistance of electrical cable (which was modified by a fire-retardant) using a safety calorimeter SEDEX. The individual insulation layers of the sample were pre-ground and each layer was subseq...

How to use fermentation residues is a burden on many biogas plants. Incorporation into arable land remains the most common approach, although application costs represent approximately the same benefit for fertilization, despite the risk of soil formation and the associated degradation of the soil's ability to retain water. An alternative how to use spent dust is to re-enter into raw material of the biogas plant or a second alternative is to use dust coal as wall surfaces in the interior because of its sorption cap...

The article describes behavior of ternary gypsum-based composites, especially the changes of properties caused by the influence of moisture. The ternary mortars are composed from gypsum, hydraulic lime, different types of pozzolan and standard sand. Pozzolans in the mixture react with hydraulic lime and form CSH and CAH phases. Presence of these phases improves resistance of gypsum against the moisture. The way of samples storage affects the development of materials structure and properties of gypsum-based mortars...

The paper proposes a new strategy against the global warming, which if applied on large scale is able to turn our cities into green oasis, decreasing their actual carbon foot-print and increasing their carbon offset. Our approach is to replace conventional roofs with integrated rooftop greenhouses IRTG, which are connected with the interior of the building by controlled flows of energy, oxygen, carbon dioxide and water. The main IRTG feature is the tight human-plant symbiosis ensured by a two flows ventilation sys...

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...

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...

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...

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,...

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 ...

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...

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...

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. ...