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The paper describes the possible applications of expanded polystyrene (EPS) granulate derived from recycling for the production of prefabricated building units. Test results of a new material called Polytech and its application in the construction industry are presented. Polytech construction system is based on prefabricated large-panel units. An important advantage of the new material is the volume representation of EPS granulate, which reaches up to 60%. So far пїЅ in order to keep the proper strength of the man...

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...

There are numerous technological and material solution in the building sector. As more and more emphasis is laid on the protection of nature in the contemporary world, new pro-ecological solutions are devised all the time. One of the most recent trends in the technological development of civil engineering is green technology. In the construction industry, it primarily means solutions with an aim of attaining efficient management of energy and natural resources, from production of building materials, through design...

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 calculated energy efficiency and specified physical properties of building materials may change significantly during the initial years of a buildingпїЅs operation under real climatic conditions. Five small test buildings with different wall assemblies were built in Riga, Latvia to compare different building construction characteristics under Latvian climate conditions. The heating energy consumption, thermal transmittance, air relative humidity and other important energy efficiency and environmental parameters...

This contribution provides a prefabricated elements constructive system, which guarantees definite features and energy saving, with integrated energy performances and structural behaviors. First, we considered the requirement framework, identifying which were the indispensable energy, structural, environmental and product performances. These choices were then examined through UNI PdR13, which is today the benchmark for Sustainability in Italy. Secondly, the market scenario of this system was defined, identifying t...

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...

Starting with the year 2020, all new buildings in the European Union, must meet the requirements imposed by laws on energy efficiency. Romania is an EU member country, accordingly must also respect these provisions. In the present study, we identified new hybrid elements for construction of closing/partitioning, energy efficient. These are the result of associations of construction materials with similar properties, having a very low thermal conductivity. The main materials used to make hybrid structures, energy e...

Nowadays concrete is the worldпїЅs most widely used building material. A decisive constituent is cement, which causes in production nearly 10% of the worldпїЅs CO2 emissions. Ultra High Performance Concrete (UHPC), a new high-tech concrete with an outstanding compressive strength of 4 to 6 times the strength of standard concrete (NSC), is the most advanced building material in reinforced concrete construction and increasingly used in different countries all over the world. Due to its high compressive strength, bui...

New innovative smart adaptive materials and optical measurement system can be implemented in civil engineering. Smart materials can be especially used in cased where fast and efficient way of reduced vibrations, weight and deflections is required. The essence of the solution is to introduce FBG sensors into the structure to make them act as its пїЅnervous systemпїЅ. The system may be implemented in existing civil engineering structures made of steel, concrete, reinforced concrete, as well as in shells and new stru...

The global level of urbanization is growing. Some estimates indicate that till 2030 the degree of urbanization will reach 83% in economically developed countries. In this context, large urban areas are already facing with problems due to water and air pollution, noise pollution, forming "heat islandsпїЅ, energy consumption, overload of rainwater collection systems and human health degradation. In this paper are presented the benefits of green roofs and the contribution they play in solving problems in urban areas....

The correct design of the construction equipment objects and their usage plays an important role in the overall efficiency of the construction with regard to the execution time, the resulting price, performance of workers on the construction site and use of deployment mechanisms. During the construction is the possibility of using alternative sources in the design of construction equipment, which may contribute to the overall efficiency of the construction. The article gives an example how to proposal a suitable t...

This study of an alloyed steel with Cr, Mo which has an important content of aluminum (0.9,пїЅ1.2)%, unconventional treated in magnetic field, is attractive because of the increasing of the durability and the wear resistance along with the improvement of the corrosion resistance. Thermo-magnetic treatments applied before the thermo-chemical treatment has consequences such as the improvement of the mechanical properties of this material. The micro-hardness of the superficial layers has been increased after the unco...

Metakaoline is a relatively new pozzolanic additive, obtained by calcination of kaolin clay at relatively low temperatures. Themselves pozzolanic additives are known for a very long time. Currently, there is interest to pozzolanic materials again, because their usage allows reducing the total environmental impact and cost of cement. The influence of metakaoline on hydration and hardening of cement was studied. The usage of metakaoline as the additive to cement composition increases the strength of cement stone. Be...

One of the priority issues of humankind is global warming, due in particular to greenhouse gas emissions (GHG), the diminishing of which is a global priority. The use of heat pump systems over conventional boiler systems to produce heat for heating or cooling (boilers, chillers) has a significant impact in terms of GHG reduction. The GHG reduction process is characterized in particular by the COP of the heat pump systems and the greenhouse gas emission intensity resulting from the electricity generation process. F...

The buildings energy performance is becoming increasingly important, because of environmental restrictions connected with CO2 emission and rising costs of fuel end energy. Respecting sustainability issues, design of buildings with improved thermal properties and optimum energy performance is preferred, whereas specific attention has to be paid not only to the design of building envelopes, but also to the thermal insulation of buildings subsoil. To obtain buildings with high thermal resistance and sufficient therma...

Solar energy technologies have been in continuous development to cope with the increasing demand. Since the solar energy supply is variable in daytime and zero at night, a considerable amount of solar energy should be stored during the daytime to meet the demands at night. In any solar energy system, a storage unit is required because of the non-constant nature of solar energy; at certain times, only a very small amount of radiation or no radiation is received. This introduces the idea of using Phase Change Materi...

In the present days the need of obtaining good and economical solutions for thermal insulation of the new and old buildings, it is compulsory. This fact leads to the need of developing new insulation materials all over the world. Such a new material it is tasted now in the west part of Romania, named Thermoconfort Plus B. The panels are made by polyurethane rigid foam combined with polyisocyanurate which is laid out between two sheets of vapour barrier material. The edges of the panel are factory manufactured to a...

The possibility and practicability of usage aluminiferous waste in the production of aluminate cements were studied. Aluminothermic slag, calcareous component and alumina in row stock was correlated for different compositions of aluminate clinkers. Clinkers were making by electric-arc melting at temperature 1600 ??. There was found a difference in mineral composition under conditions fast and slow cooling aluminate melts. In case of fast cooling main phase was calcium bialuminate and high glass-like phase content....