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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. ...

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 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...

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...

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...

There are many many historical buildings maintained in the world, whose construction, namely exterior wall, is made of solid masonry. These constructions have excellent thermal inertia, but also a range of humidity and thermo-technical problems. Finding a solution for these problems is a siginficant task, since most of the inner plaster is decorated with paintings, which are a cultural heritage. This paper deals with the solution to selected construction problems and their two dimensional simulation of the thermal...

The aerogel is a nanomaterial that may represent a viable alternative to the traditional thermal insulations, especially when it is required an increase of the thermal performance of the building envelope elements and also a reduced thickness of their finishing layers. The paper presents the conclusions of some studies regarding the thermal behaviour of the aerogel and also some improvement possibilities of this material and of other materials, by integration of the aerogel in their structure. At the same time, th...

The article presents the possibility of application in civil engineering of highly ecological PET foam, manufactured from 100% recycled plastic packaging. It may find uses in construction of numerous engineering structures, such as pedestrian and cycle footbridges. Properly processed waste from post-consumer PET packaging may constitute a quality structural core for use in multilayered composite materials, commonly referred to as sandwiches. Their constructional function is to provide a distance between highly rig...