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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...

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...

Energy efficiency and renewable energy are considered to be the twin pillars of sustainable energy policy and are high priorities in the sustainable energy hierarchy. In this context of continuous improve of energy efficiency in buildings; each state has developed different national politics on this direction. The obligation of the EU Member States to assimilate the strategy proposed by Energy Performance of Building Directive (Directive 2010/31/EU) determined the local communities to find financial resources and ...

The paper discusses problems associated with attempts at limiting waste that is the result of the functioning of the modern economy. This is associated with the use of new, sustainable systemic solutions in terms of the manner of designing cities and buildings that use existing resources to the highest possible degree while not generating waste. The impact of new, ecological cities is to be neutral to the extant ecosystem. Buildings are to be erected solely from recyclable materials and roofs covered in greenery i...

Developing biocomposites materials is a part of the strategy of sustainable development in construction. This paper presents the advantages, the disadvantages and problems, still unclear, to achievement the biocomposites materials, HEMPCRETE type. The most important thing, highlighted by literature regarding the creation and use of this material type, is the extremely low impact with the CO2 pollution, which usually accompany technological manufacturing processes, putting in place and exploitation of construction ...

Sustainable use of natural resources and recycling/reuse of wastes are two of most current upcoming environmental problems, and they play an important role in the circular economy, as recycling of waste can give an important contribution to the reduction of natural resources. Ceramic tiles production is one of the industrial activities involved in using natural resources like clays and sands. On the other hand, in Italy, sanitary landfills are, nowadays, the main place, where bottom ashes are finally treated. This...

After the adoption of the Law no. 221/2015 and the new Code of Contracts, Legislative Decree no. 50/2016, Italy has become the first European country that has imposed Minimum Environmental Criteria (MEC) thus amplifying the importance of Green Public Procurement (GPP), already widespread in Europe since the late 90's in a totally voluntary way. In Italy, MEC have been approved with specific Decrees by the Ministry of the Environment and concern numerous areas of intervention (mainly as regards the supply of goods ...

The paper presents the research on the modification lightweight cement composites with organic fillers by fly ash and anionic bitumen emulsion addition. Organic fillers used in composites were: common reed (fraction 2/10 and 10/20 mm) and conifer sawdust (fraction 0/2 mm). The reed Phragmites australis is a notably common plant in Poland that grows on waterlogged lands. This material is renewable, ecological, and while vegetation absorbs carbon dioxide. To determine the influence of two factors on compositesпїЅ pr...

Mortars and colored concrete are used in construction for the execution of masonry blocks, tiles and other building elements and materials that complement the aesthetic appearance of buildings, contributing to their architectural finishing. Pigments are usually used for coloring of the mortars and concretes based on cement mineral. The organic pigments are used in a more limited extend for this purpose. The life time of the facades realized with silicate cement largely depends on the compatibility between pigment ...

Nowadays, an important objective for researchers is to find an alternative to build cheaper and greener, sustainable and also durable. To discover a material with better thermal and acoustic performances than conventional concrete by using natural and renewable components in its composition became also an obvious trend. The agriculture products, mainly those considered as waste in this field, fulfill all the above mentioned requirements, being also widely available and with higher thermal and acoustic properties t...

Passive houses primarily belong to the category of buildings with very low energy consumption for object heating. Their overall energy performance is affected by a number of indicators, including in particular: solution of building structures and details on boundary of building heated space, characteristics of used materials and the choice of opening fillings. In the initial design phase of the building it is necessary to ensure maximum utilization of solar gains and internal gains from people and appliances. Howe...

The contribution focuses on the issue of realization of stoves in energy passive houses. In the context of building airtightness, implementation of the stove is considered as a significantly weak element in the construction of energy efficient buildings. Conventional stoves and fireplaces disrupt the airtightness of the building envelope. The paper describes suitable types of stoves, materials of fireplace insert, types of fuel and connection possibilities to the heating system. The attention is paid to meeting th...

The paper describes the technology of controlling a new material called Polytech used for the production of prefabricated units. Prefabricated units made from a modified Polytech mortar based on expanded polystyrene derived from recycling were used to build a residential object. Prefabricated elements are load-bearing and, at the same time, insulating elements in the form of wall panels. In order to control the prefabricated wall with a lintel under realistic conditions, a control technology was suggested that inv...

The marine environment is considered to be a highly aggressive environment for metallic materials used in the construction of the various elements of the structures. The aggressiveness of the marine environment is given by a number of chemical, physical and mechanical factors. They make maintenance of structures to be very difficult and very high costs are allocated. The phenomena of degradation by corrosion at level onshore and offshore are favored and accelerated by a number of factors related to long periods of...

Construction of green buildings has become a kind of global trend, but its implementation varies greatly by country and region, including the rate of growth in green involvement, triggers and obstacles impacting their growth. Green buildings gives to the forefront of energy efficiency also the impact of buildings on the environment, the environmental burden through production of raw materials and the impact of buildings on the whole region. Green building is therefore designed, built and operated also with regard ...

Every year just a small part of the Italian building stock hurts a significant energy regeneration, which occur mainly on occasion of programmed wider restructuring of the building. Therefore, the dynamics of the construction sector are still too slow compared to the пїЅ20-20-20 commitmentsпїЅ (The Directive 2012/27/EU Energy Efficiency entered into force December 4, 2012) and they are not enough focused on new consistent buildings and planned renovations. It should therefore promote and facilitate the process of ...

Self-compacting fibre reinforced concrete summarizes both the advantages of selfcompacting concrete: reducing environmental noise pollution, faster construction time, improved quality of concrete surfaces etc., as well as the fibres benefits: better mechanical performance, ductile failure and so on. Self-compacting fibre reinforced concrete is not currently used in Romania especially due to the lack of normative research respectively the national regulations in this particular field. One of the national research p...

Modern drying of wood remains one of the basic engineering procedures influencing the quality, product cost and duration of production cycle at the woodworking entities. The drying equipment often has evolutionary nature of development. It is generally reached due to upgrade of the existing complex of the drying equipment, however the use of innovative technologies is necessary for increase in high-quality, regime and also energy efficient indicators. The analysis of theory of drying, technologies of various proce...

This paper presents studies on the development of ecocomposites based on natural rubber and plasticized starch. Natural rubber is the most commonly used elastomer worldwide due to its low cost; it is renewable, non-toxic and shows excellent physical properties. Natural rubber is not used as such but in the form of mixtures which generally contain: fillers, plasticizers, crosslinking agents and other ingredients that provide various features to the final product. Replacement of active fillers in rubber mixtures suc...

Economic development in recent decades has made environmental protection not only a local but also global problem. This approach is currently the basis of operation in this aspect in European Union. The eco-friendly business attitude should not, however, result from the fulfillment of statutory obligations, but from the activities that go after the accepted standards. Creating an environment-friendly, modern company image becomes a current times challenge and build a positive climate for its development. One of th...

The aim of the work is to evaluate the advantages of the application of renewable energy sources in an office buildings in the Czech Republic. Given the demands on the application of renewable energy sources and the issue of lack of free spaces in cities, this work will address the evaluation of the advantages and applications of solar energy and geotermal energy as the resources with easy applicability in the construction of new office buildings. Data for comparison are obtained from national statistics and alrea...

The concept of energy efficiency is applied in the context of efficient use of energy materials and media in various stages of production, transmission, distribution and energy consumption. Implementation of the principles of energy efficiency in practice is taking action, whether producers or consumers of energy, resulting in the reduction of energy consumption per unit of output without reducing the level or quality of services consumed. Buildings form a basic pillar of smart cities concept where all life proces...

In recent years, the focus is more, more often put on environmental protection and energy saving, therefore, a variety of alternative materials, and alternative procedures in the field of road construction are search. One potential option is to reduce the temperature in the production, laying and compaction of asphalt mixtures that favourable affects a carbon footprint. This is achieved by the use of organic additives and waxes, chemical agents or water (foamed bitumen). Depending on the additives, it is possible ...

The effect of ambient conditions on the properties of three different types of concrete containing ground granulated blast furnace slag, silica fume, and waste brick powder as partial Portland cement replacement is studied. The samples are exposed to the external environment in a test facility located in the city of Prague. The upper horizontal surfaces of the specimens are covered so that the wind, rain, snow and sun radiation affect only the vertical surfaces, similarly as in their practical application on build...

The microclimate of buildings forms an integral part of everyoneпїЅs life, because each of us spends a part of the day, sometimes more, sometimes less, in the closed premises of buildings. It is a specific part of climate that has a dynamic development and mainly comprises temperature, humidity and concentration of harmful substances in the premises. And one of these is CO2. This paper follows the author's previous publications which also deal with the issue of CO2 concentration in building premises, including the...

This article is referring to a study regarding the energy consumption and data for the internal heat gains and opening hours at a big size commercial building built in Bucharest, Romania. The monitoring was done during the maintenance building period of time starting with the opening day till the present days. It was calculated the energy demand for heating, cooling, ventilation and lightning systems depending on the average daily running hours and on the internal heat gains for each type of area destination (like...

This paper deals with current applied research focused on energy gain from wastewater (WW) for heating and cooling in a new multifunctional building. Energy-saving and environmental protection technologies are becoming one of the most important issues in the design and construction in EU. Energy gain from WW is often associated with piping exchangers, but there are alternative methods such as input pipes with pumping station (PS) and heat exchanger system (HES) with automatic surface cleaning and solids removal. E...

The case study analyzed in the paper refers to a group of new buildings built near the campus of the University Politehnica of Bucharest. The UniversityпїЅs campus has its own cogeneration power plant equipped with two reciprocating engines using natural gas. Each engine generates 800 kWe of electricity for UniversityпїЅs own consumption and for selling it on electricity market. During the winter time the heat recovered from the two engines, is used within the district heating network of the UniversityпїЅs campus....

The underground architectonic objects are often located at low depth. This is why, in order to protect objects located on the area or minimize the negative impact of works performed on people and the environment, roadheaders are widely applied, with the use of which excavating takes place in a mechanical way. BoomпїЅtype roadheaders deserve special attention in the group of roadheaders. A significant feature of the machines is the possibility of building underground objects of any shape and size of crossпїЅsection...

Several concrete mixtures suitable for constructing engineered barriers in radioactive waste disposal facilities are designed and tested. The mix design is based on the utilization of a natural sorbent acting, at the same time, as supplementary cementitious material replacing a part of Portland cement and fine filler capable of radionuclide absorption and fixing. A representative set of engineering properties of the hardened concrete mixes is determined, including the pore size distribution, bulk density, matrix d...

Concrete production has high adverse effect on the quality of environment, and its sustainability is open question for material researchers and producers. In addressing the environmental concerns of concrete manufacturing and problems relating to the disposal of wastes and industrial by-product and also economic advantages, application of secondary raw materials in composition of concrete mix is of the particular importance both from the environmental and financial point of view. A substantial growth in the consum...

New building materials were obtained in the last decades by using different types of cements, aggregates, additives or additions. Additions such as s powder, aggregate, fiber, etc. were tested for obtaining new properties of concrete or for finding a way to consume the wastes. The paper presents the experimental results obtained on fly ash concrete with waste fibers. The concrete was prepared with substitution of cement with fly ash in different dosages (10%, 15%, 20%, 30% and 40%) and two types of fibers (hemp an...

Modern buildings require energy-efficient heating and cooling method for the both parts of the system, the heating/cooling source and the heating/cooling distribution system. Modern heating and cooling systems typically combine a reversible heat pump with a low temperature radiant system. Thermally activated building systems (TABS) use the large thermal mass of concrete from building structure as a buffer for lowering the cooling and heating loads during the day. In this paper we illustrate the floor covering infl...

Development of Fibre Engineered Cementitious Materials with Self-Healing Capacity (SH-FECM) was an important goal of the recent research programmes conducted in NIRD пїЅURBAN-INCERCпїЅ Cluj-Napoca Branch. Several theoretical and experimental studies were performed in order to improve the composites, considering both, fresh and hardened state properties and also the performance as filling material of the narrow spaces at the beam to column interface within the Hybrid spatial joint model [1]. Present studies are foc...

The benefit of recycling industrial by-products in the construction industry led to growing interest in exploring and potentially exploiting these by-products, in the context of sustainable development, and in creating new materials. Fly ash is a type of byproduct waste, having enjoyed considerable attention, especially from the perspective of creating and perfecting fly ash based geopolymer concrete. In Romania, over 80% of industrial waste is deposited, this being the most widely used method of waste disposal. T...

Form-found designs are evolving structures reflecting material and structural behaviors and environmental context by utilizing prevalent winds, radiation, and temperature. The paper applies case study analysis of free-form wooden architectural envelopes designed by Renzo Piano Building Workshop, which improve the energy performance of the buildings. The use of digitally designed and manufactured structural wood can radically reduce the amount of energy consumed by materials used in building during whole life cycle...

Geopolymers are innovative, ecological, low-cost, inorganic polymers derived from the naturally occurring geological materials which combine low temperature, polymer-like processing with high temperature stability and fire resistibility without toxic smoke generation. To increase efficiency of geopolymer composite materials in aerospace where the fire resistibility is critical, their incorporation into sandwich panels must be applied and evaluated. This paper presents drum peel strength (ASTM D1781 standard) of bo...

The article discusses basic directions of construction sector development in modern ecological conditions, principles of sustainable development of cities and the problems hindering implementation of green building principles in the Russian Federation. The article indicates the most promising concept of a building complex development which is the construction in compliance with environmental standards (green building). The peculiarities of green building in Russia are considered and the reasons for its slow develo...

A considerable progress in industrial construction and civil engineering makes it necessary to increase the production and application of new heat-insulating materials based on accessible environmentally safe mineral products. The mineral composition and structural characteristics of KareliaпїЅs natural raw materials are favourable for the production of ceramic heat-insulating materials with required properties and characteristics such as porous structure, low density, low thermal conductivity and high strength. T...