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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 ...

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 ...

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...

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 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 ...

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...

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 ...

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...

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...

Anthropogenic pollution originating e.g. from waste landfills can migrate into the ground and significantly change its properties. Moreover, the interaction between soil and pollutants may change soil behavior as well as cause geotechnical problems. The aim of the study was the assessment of the impact caused by inorganic contaminants on consistency limits (plastic limit and liquid limit) of fine-grained soils. Laboratory tests were carried out on bentonite, kaolin and clay using KCl, MgCl2 and NaCl solutions. The...

The purpose of this work was to investigate the possibility of wood preservation by its modification with different substances through the penetration method and to study the impact of the process on some operational properties of the wood material. The experiments were conducted with poplar wood (samples 10x1x1 cm), which has low density with well-developed capillary system, good absorption capacity and belongs to low operational capacities tree species. Alkaline activated hydrolysis lignin (AAHL), Cu2S and Malei...

Thermal insulating materials were obtained from diatomite and with burnable reinforcing additives, modified by synthetic and natural polymers. As burnable additives used rice husk, reinforcing additive is a basalt fiber, modifying polymer is polyvinyl alcohol and starch. Thermal insulating material obtained by mixing dry water mixtures at various ratios of components followed by drying and calcining at a temperature of 750 C. Parameters were determined linear shrinkage, density, compressive strength, the bending s...

Multi Storied structures are used worldwide and have outstanding advantages in the use of composite materials in structural application. This study heads to an experimental study to reproduce the behavior on a composite joint configuration. Due to the lack of knowledge, during the last few years a lot of studies are based on the semi-rigid composite joints that can provide useful data about the behavior and the resistance of these connections. A number of two tests were performed to obtain a better development of ...

This paper describes an experimental analysis of damaged concrete corbel strengthened by gluing carbon fibre composite fabrics. The purpose of the investigation is to study all changes in behaviour and then their contribution to a better understanding of reinforced concrete corbel. Five reinforced concrete corbels are tested under tree-points bending to failure. Four of them are damaged at different load level up to 80% before strengthening. Test results show that strengthened corbel specimens using glue given an ...

The main theme of this article is a problem of storing underground utilities in different types of country. Supply services must meet dissimilar requirements for placing in rural or in the urban zone and respect all limits, which are binding in the known area. Technical security of urban settlement is a significant part of today's modern society, as is the flawless and reliable operation of water, energy and telecommunications networks. They all are a commonplace in each urbanized land and have an important impact...

This paper presents a study of performance evaluation of some fluid cement-based mortars containing mineral admixtures used as structural bonding material for fixing reinforcing steel bars in hardened concrete. The paper includes the developing of performance anchoring mortar for post-installed rebars based on ordinary blended cements. A series of standardized tests were performed within the experimental setup with the objective of assessing the performance of the mortars in terms of fluidity, cohesiveness and ear...

The article deals with the types of facility management approaches to the management and maintenance of utilities. It addresses the basic kinds of management and maintenance of these buildings in relation to the valid legal regulations of the Czech Republic, and it also discusses the need to solve these problems mainly because of the wear of buildings due to time, mechanical damage and weather conditions. Neglect of timely maintenance and repairs reduces the utility value of the building, which is contrary to the ...

Development of high strength concrete has been continuous over the years, its production becoming available at competitive prices to the construction industry, thus moving away from being a novelty product. Although high-strength concrete properties have been widely studied for nearly 100 years, currently available design standards for concrete structures contain stipulations based on research conducted on concrete with lower grades than those available today. The modulus of elasticity is a very important mechanic...

The recent demands regarding energy efficiency of buildings across the European Union, namely the nZEB concept, impose among other improvements, the thermal behavior optimization of building components that define the building envelope. In order to achieve the imposed nZEB criteria, conventional thermal insulations with increased thickness have to be used, which is inconvenient in several cases. The paper presents an alternative solution, given by Nano insulation materials, such as aerogel and vacuum insulation pa...

The paper refers to an experimental program aimed at evaluating the characteristics of masonry, with the objective of developing an innovative system for masonry, destined to be used for facades and envelopes. The purpose was to develop new masonry elements with good performance at thermal transmittance and good behavior at noise, fire and durability. Technical and economic feasibility of the masonry prototype systems was validated by experimental tests, according to European standards. The strategy for the develo...

In last years, recycling has become a strategic factor in global politics, a vital component and a cost factor for economic development and the progress of society as a whole, generating a number of major global concerns. Exceeding twice the sum of all materials used in construction, annual concrete consumption around the world amounts to approximately 10 trillion tones being by far the most used building material and the partial or total replacement of a component of its mass with recyclable waste has a major pos...

The handling and disposal of voluminous sludge produced from water treatment plants poses difficulty to environmental scientist and engineers. In fact, its environmental friendly management and disposal is challenging task and requires careful consideration. In this study, sewage sludge ashes were examined as potentially supplementary cementitious materials. The raw sewage sludge was provided by two different municipal waste water treatment plants, coming from Poland and Greece respectively. The calcination of pre...

The basic contractual instrument among all involved parties of construction projects in the Czech Republic is a contract for work according to the Civil Code of the Collection of Law of the Czech Republic. The contract is further supplemented by provisions based on long-term business experience and needs of contractual partners. An essential part is the type of price, its amount and the method of determining or adjusting the price. For green constructions in general and green buildings in particular it is customar...

The use of weak local soil as well as the recycling of existing worn-out structures such as old road pavements using micro particle road binders are a beneficial ecological solutions. Parameters of the soil stabilized with binders significantly affect the load bearing capacity and durability of the built structures. Mechanical parameters of the soil are therefore needed in the analysis and design of soil structures. Determination of the exact value of these parameters in indirect tensile test is related to the nee...

The aim of this study is to explore the possibility of recycling waste materials of brick aggregates (BA) and demolition concrete aggregates (DCA) in the self-compacting concrete (SCC), by studying these fresh and hardened properties. A reference mixture based on natural aggregates (NASCC) and six mixtures incorporating recycled brick aggregates (BASCC), recycled demolition concrete aggregate (DCASCC) and combination of recycled brick and demolition concrete aggregates (BDASCC), as replacement of natural aggregate...

The building sector is interested in developing new types of structures capable to resist seismic loading. There is introduced a new structural detailing of mix steel-concrete structures. The innovative design consists in use of the precast concrete slabs and steel frames, assembled by post-tensioning, of the prestressing procedure for the steel members and also a different column-beam connections having resilient characteristics. Each of the listed features is also special. The prestressing reinforcement is locat...

This contribution results from the experiments conducted in the experimental gallery in the limestone pit. The gallery consists of three horizontal parts, two of them are parallel. The premises of the experimental galleries are used for testing and research in the area of explosion prevention. The partition masonry walls were built inside the gallery and they were subjected to the blast load induced by air-gas mixture. The paper introduces the principles for determining the dynamic load and for its simplification,...

The primary aim of earthquake resistant design is to prevent building collapse during the seismic event, but severe earthquakes have a low probability of occurrence during the life time of the structure, therefore in contrast to traditional structural design in earthquake design, structures are permitted to work in post-elastic domain under seismic load. It would require a large lateral stiffness of the structure and an expensive resisting system to design the building to have an elastic response. Because of these...

Sustainable design attempts to be perceptive to the environmental impact of the building project at each construction stage by evaluating the site, the embodied energy of the selected materials, as well as the proper construction techniques, adjusted to the local conditions. Moreover, physical hazards (flammability, corrosion) and/ or health hazards (toxicity, irritations) of the materials are especially important not only for the construction workers, building owners and occupants, but also for the environment, c...

The presented paper deals with the design and examination of steel towers of electrical transmission lines with circular or polygonal cross section. Structures of this kind are a safe and reliable option when selecting the appropriate structural solution, but nevertheless often remain omitted due to difficulties with design methodology. The cross sections of conical towers are in majority of cases categorized as class 4 sections. Being classified as such, they are in certain loading situations considered as shell ...

The article discusses the need to introduce energy management of municipally-owned buildings provided by the concept of Smart Cities. Cities use many buildings. These buildings also have a different nature of use, such as offices, schools, social care homes, etc. All these buildings consume energy that needs to be monitored and regulated. Energy management needs a large amount of relevant data on these buildings together in one comprehensive system. When planning building revitalization, it is necessary to have su...

This article is referring to a short study regarding the energy efficiency status in retail industry in Romania, in particular an analysis of the big sizes commercial buildings in this matter. It contains data which will allow us to compare an existing building with the industry norms in terms of the energy consumption and energy costs. Additionally, there are some recommendations provided to be taken care of in the near future for controlling energy better, using energy in a more efficient way and reducing avoida...