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The paper presents a new technique for making foam glass gravel by expanding at high temperature recycled glass waste with a liquid carbonic foaming agent (glycerol) in combination with sodium silicate (also called “water glass”). Unlike the conventional methods known worldwide in similar technological processes, the paper proposes a fast, economical and clean unconventional technique (microwave irradiation), applied to a very small extent in the industrial sector, although in the household it is a widely used process. The experiments carried out by the Daily Sourcing & Research Company on a 0.8 kW-microwave oven aimed at the manufacture of foam glass gravels with physical and mechanical characteristics almost similar to those industrially obtained by conventional methods, simultaneously demonstrating the superior energy efficiency of the technique of using microwave energy as an unconventional source. The products experimentally made had low thermal conductivity (between 0.057-0.063 W/ m·K), high compressive strength for this material type (up to 5.9 MPa) and very low pore size (below 0.9 mm). The specific energy consumption had values between 0.83-0.88 kWh/ kg comparable to those industrially achieved, but it should be considered that the use of a high power microwave equipment could improve the process efficiency by up to 25%.

Experimental results of manufacturing the cellular glass from container glass waste using an unconventional heat treatment technique (microwave energy) are presented in the paper. The cellular glass has physical, mechanical and morphological characteristics suitable for using as an insulating material in construction constituting an alternative for existing building materials. By comparison with these materials, the cellular glass has a higher resistance to mechanical stress, fire, humidity, attack of rodents, insects, bacteria, etc. The apparent density and thermal conductivity of the product are low (below 0.34 g/ cm3 and 0.062 W/ m·K, respectively), the compressive strength is acceptable (over 1.2 MPa) and the material structure is homogeneous with closed pores evenly distributed. The originality of the manufacturing technique of cellular glass presented in the paper is the use of microwave energy, unlike the conventional methods currently applied in the world. The advantages of the use of this unconventional technique are the low specific energy consumption (around 1 kWh / kg) and its non-polluting character.

The paper is the second part of the article that presents experimental results of the research developed in order to obtain innovative systems for corrosion protection of steel. There were created three recipes of an innovative type of a coating, starting from an acrylic compound in aqueous dispersion, with ceramic microspheres, in which it was introduced, in different proportions, a kaolin additive. Each product was applied on steel surfaces, in four - layered systems. There are presented results referring to the systems behavior during their exposure to corrosive environments in accelerated laboratory conditions that simulated three types of aggressive climate conditions. The adherence of the systems to the steel surface indicated a new possible merge between nanotechnology and the use of natural resources, and also a new possible direction for the use of kaolin in the coatings industry, in order to obtain a new type of coatings with a good reaction to the aggressive actions of the current climate from various countries. There are also analyzed, by comparison, the results obtained on the three and four-layered systems, respectively (the dates for the three-layered systems being initially presented in the first part of the paper).

The paper deals with some aspects regarding "Experimental Research and Laboratory Testing for Seismic Qualification DBE B, Seismic Edge HCLPF = 0.4g, Automatica 1 (2) - 52900 - PL2023 Junction Box". Seismic qualification was performed by physical experiment on the 150 kN Shaking Table at INCD URBAN INCERC IASI. The provisions of the - Technical Specification. Safety Systems Equipment Cabinets. Cernavodă 2. 82–68000–TS - 003, Revision 0, November 2001, - Addendum to Technical Specification 82–68000–TS–003, Rev. 0, Safety Systems Equipment Cabinets and - SR EN 60068-3-3:1994. Environmental testing. Part 3: Guidance. Seismic test methods for equipments, have been observed. The seismic qualification results and the related conclusions are contained in the paper.

The paper presents the outline and function of a system for field assessment and the structure of a database for post-earthquake inspections, to be used with the Romanian Methodology for rapid buildings assessment, indicative ME003/2007, and for other research purposes. Functioning mode of the system for assessment in emergencies caused by earthquakes and the structure of the data collected by the field teams that participated in post-earthquake inspection are presented in this paper. A system for interdisciplinary assessment was taken into account for strong Vrancea intermediate earthquakes, but it will be useful also for crustal earthquakes of local or regional extent. The proposed system envisages a coordination centre and a clearinghouse at Bucharest, in NIRD “URBAN-INCERC” that coordinates branches of the territory (Iaşi, Timişoara and Cluj Napoca). Given the large area affected by Vrancea earthquakes, the system will pursue the establishment of regional centers also in the cities of Braşov and Constanţa, where there are universities in the field. To demonstrate the relevance of the system, the paper presents a case study of two buildings located in Bucharest downtown. By exploiting a software application created at INCERC Bucharest Branch, numerical values and charts can be obtained for all buildings investigated by the INCERC inspectors.

Because of the great rhythm of city developments, there is a great need for a new cost effective method for ground improvement. In this paper, a few chemical improvement technologies and a new biological ground improvement method called Biogrout are discussed. The method, used in the paper for a Sarmatian sand in Transylvania (Feleac locality) implies using microorganisms as catalysts in order to induce a microbial carbonate precipitation (MICP) to increase the strength and stiffness of cohesionless soils. For this calcium based procedure, the bacteria Sporosarcina Pasteurii (DSMZ 33) is used, while for the treatment solution urea (CO(NH2)2) and calcium chloride (CaCl2) are used. The study presents the triaxial testing of sand probes treated with Biogrout and the comparison of results obtained with untreated sand probes.

Having an easily built house has been always one of human wishes. Prefabricated home makes this wish come true because of its affordability and fast completion. This paper gives an overview of different types of prefab home and its terminology. This review sheds light on the characterisation of prefab home, which takes the aspects of off-site technology, mass customisation, and sustainability into consideration. This paper is confined to general review of prefab home without going through different systems utilised in off-site technology. In spite of the fact that prefab home has many advantages, which are discussed in this review, it suffers from a few drawbacks which should be considered by designers. Various exploitations in this field may merit further research in future, including finding the optimum prefabricated systems among the existing systems such as roof, wall, and floor systems for different applications of prefab homes. Nevertheless, there is still a universal design and practice code for prefab homes that emphasize on green technology and sustainability yet to be discovered.

The paper presents the aim and objectives of modernizing the energy system of current buildings as well as of designing and executing new buildings with a high Energy and Environmental Performance. It is necessary to refer to the European Strategy (Europe 2020) and to the European Directives, transposed into the national legislation, while the technical and economic solutions to the objectives resulting from the above mentioned purpose complete the dimension of the logical structure of this procedure for reaching the objectives. The economic and especially social importance of comfortable and hygienic living conditions, without excessive costs and without affecting the climate also stems from the climate impact on the current living conditions and use of energy sources. The summer of 2003 had a tragic aftermath at the European and international level, consisting in over 40000 victims of the heat wave and of the buildings’ incapacity to adapt to extremes such as exceptionally intense climate hazards. This highlighted the vulnerability of the built environment compared to climate hazards characterized through an ascending evolution, Romania included. The system of quantitative assessment of the building’s Energy and Environmental Performance, part of the procedure for Energy and Environmental Configuration, entails separate expertise and diagnosis phases which allow elaborating scenarios and strategies for energy modernization. The modernization scenarios are elaborated based on the diagnosis of the building, scenarios differentiated through technical and economic indicators. Scenarios allow the modernization strategy to be elaborated. The energy modernization strategy / designing of new, energy performance buildings is based on the Energy Configuration of Buildings which is the detailed modelling of ownership transfer processes and the assessment of economic efficiency of design / exploitation solutions. The calculation methods are subject to validation and sensitivity analysis.The paper presents a case study starting from a condominium in Bucharest, built in 2010. The process was followed starting with the Building’s Certification in its current status (falling under the D energy class, mediocre) and ended with the transformation, by means of energy compliance, into a Nearly Zero Energy Building (NZEB).

Terrorist actions of the last decade obviously determine a reconsideration of the buildings safety, especially for those with special destinations (embassies, military facilities, nuclear plants etc.). Thus, the conception phase should include nowadays scenarios with exceptional actions, other than seismic loads: impact, explosion, failure of supports.It is well-known that, after earthquakes, the most situations of structural collapse are determined by the terrorist attack using explosive. Even more, it has been assessed that the main reason of loss of life is not the explosion itself, but the partial or total collapse of the exposed building.In order to secure the structural integrity, collapse analysis should be taken into account as a complex phenomenon, composed of many processes that could be studied separately or as an ensemble. These processes are: the extreme action causes, design requirements, vulnerability of the structure, starting and development of the collapse, its final effects. Study of these processes leads to additional special measures for design stage and, on the other hand, to valuable knowledge for controlled demolition of tall buildings, as part of bold urbanism projects in densely populated zones.Considering the above mentioned facts, this paper presents the results of a thorough analysis of a frame structure under explosive loads. The first part of the paper refers to the analysis of a phenomena assembly related to explosion and to the effects resulting from a terrorist attack using explosives (structural elements deterioration and failure, collapse initiation and eventual total failure). The second part of the paper presents an original approach to analyze a building structure under extreme loads, using both classical (pushover) and modern (applied element method.

In the context of the growing demand for energy from renewable resources, there has been a lot of interest in the use of systems that use solar energy. The basic principles for determining the performance of solar panels have been established since the 1980s, but the accuracy of these determinations has improved over the years. This paper presents the evolution of estimation methods of solar thermal systems in Romania in recent years and shows the qualitative evolution of these estimates, with obtained values much closer to reality.

Record levels of air pollution, leading to environmental degradation, deteriorating health and climate change, are affecting cities around the world. However, due to the confinement measures imposed at the beginning of the COVID-19 pandemic, reductions in nitrogen dioxide (NO2) concentrations - one of the main traffic pollutants - have been reported in many cities in Europe and around the world: by over 50% in Barcelona as of March 21, 2020, 64% in other cities in Spain, about 40% in London or about 50% of carbon monoxide (CO) levels in New York. In this context, the paper presents the results of monitoring NO2 concentrations within the INCERC Bucharest Branch, located in the eastern part of Bucharest, the capital of Romania.

The paper is mainly focused on the investigation of the seismic response of reinforced concrete frames with masonry infills. Numerical results obtained with a strut model built in ETABS 2016 software are compared with the experimental results obtained on a full-size model. Tests were conducted in 2018, at the Technical University of Civil Engineering of Bucharest, on a reinforced concrete frame with masonry infills and on a bare reinforced concrete frame under compressive and shear loading. A static pushover analysis method was selected, and results were fairly compatible, even though some differences in the initial stiffness, as well as in the post yielding stage, were observed between numerical and experimental results. The model is presented, proposing a simple engineering method to be used in calculations.

The purpose of this paper is to present a procedure used in the assessment of the real heat transfer characteristic of shell and tube and plate heat exchangers. The theoretical fundamentals of the procedure are introduced as well as the measured data collection and processing. The theoretical analysis is focused on the adoption of criterial equations which, subjected to certain verification criteria presented in the paper, provide the most credible value of the convection heat transfer coefficients inside the circular and flat tubes. In the end two case studies are presented, one concerning a shell and tube heat exchanger operational at INCERC Thermal Substation and the other concerning a plate heat exchanger tested on the Laboratory Stand of the Department of Building Services and Efficient Use of Energy in Buildings of INCERC Bucharest.

The energy footprint of a building is an operational characteristic specific to the building structure as well as to the energyrelated operational conditions of the building. This paper presents the experimental programme carried out on the support of the CE INCERC Bucharest experimental building in the 2008-2009 cold season and the results obtained in the form of the building energy footprint. At the same time, the building energy footprint before the energy-related upgrading (2003-2004 cold season) are presented, as well as those subsequent to the energy-related upgrading (thermal protection, equipping with a ventilated solar space and heating system replacement). The character natural laws of the energy footprint are emphasized. This paper presents a theoretical substantiation of the use of the energy footprint method in the case of condominiums in the form of the operational method, which is useful in settling the functional characteristic in any climatic conditions and in any operational conditions.

Since ancient times we know the efficiency of the technology of building houses using clay soil in various forms: mixed, in the form of bricks, etc. Until now, there have been numer-ous studies to improve these technologies and to obtain structures that are as resistant, com-fortable and durable, as well as for the recov-ery of industrial waste. This paper presents an experimental study on the possibility and effi-ciency of the addition of industrial waste in order to obtain suitable clay mixtures for mak-ing unfired clay bricks. For this purpose, 6 compositions based on clay and industrial waste have been made. The industrial waste was ash from Mintia (thermal power plant), limestone sludge, plaster sludge and dumped waste from the processing of imported ore. Analysing the followed physical-mechanical parameters, for the realized mixtures, it is con-firmed that the industrial waste can be suc-cessfully used as an addition in the clay ma-trix destined to make bricks from unfired clay.

Timber framed masonry houses represent a traditional type of house that can be found in many countries in the world, having small differences in details though. In Romania, this type of house is spread around the Vrancea seismic source, but not limited to that area. Until now, no studies were done on the Romanian timber framed masonry houses in terms of ambient vibration testing and analysis. This paper presents the first study of this kind, conducted on a house with timber frames and masonry infills, which is located in the National Village Museum, namely representing Sarbova area, Timiş County. Ambient vibration tests were done using velocity sensors, and thus determining the modal frequencies, and a simplified analytical study was further conducted leading to similar results as the experiment.

The process of designing / erecting a new building involves, among others, the identification of the optimal variant for non-structural and / or finishing elements. This choice is made considering several factors, including material and labor costs, the construction duration, the desired finishing degree, the thermal and acoustic comfort offered by various solutions, the seismic area (in terms of construction weight), the expected field of use etc. The choice of the partitioning and closing solution and that of suspended ceilings is one of the potentially important factors involved also in the design and assessment of structural behavior. The purpose of this paper is to present one of the current solutions for the use of these partitioning/closing elements and suspended ceilings with cement boards on metallic or wood structures, usable both indoors and outdoors and providing a number of advantages.

Urban constructions are subject to deterioration and degradation due to the action of external factors, pollutants from air, water, compounds resulting from the combustion of fuels used for heating and transport, etc. currently, worldwide, the possibility of building cementitious composite materials with self-cleaning properties is reported due to the photocatalytic capacity of TiO2 nanoparticles, used as an addition or as a substitute for a part of cement. The aim of this paper is to present experimental research on the influence of the introduction of titanium dioxide nanoparticles (TiO2) on some physico-mechanical properties of cementitious composites. Experimental research has been carried out on cementitious composite material containing TiO2 nanoparticles respectively the evolution of the following parameters was analysed: setting time, apparent density, absolute density, porosity, water absorption, water absorption by capillarity and white degree. The main objective of this study was to analyse the influence of the presence of titanium dioxide (TiO2) nanoparticles on the physico-mechanical properties of cementitious composites.

The paper presents experimental results of the research carried out in order to obtain an innovative finishing/protection product for plasterboard surfaces, using sunflower seed husks, waste generated by the edible oils industry. In the form of an addition consisting of one or two-dimensional fractions, sunflower seed hulls have been incorporated into a finishing/protective coating product, the latter acting as a binder. The multilayered application of the resulting products, on gypsum board surfaces, led to a coating having good adhesion to the support as well as good thermal insulation characteristics (between 0.165 W/m.K and 0.095W/m.K), despite the small thicknesses of the coating (between 3.15 mm and 5.10 mm) compared to the traditional products with thermal insulating properties.

The aim of this paper is to present the experi-mental research carried out in order to ensure compliance with the EU law, when placing on the construction market elements larger than those framed in the harmonized European standard. The research methodology followed experimental testing components of the rein-forced concrete type manholes with an inner circular section whose nominal dimensions exceed DN 1250. An important issue for local communities has been collecting household waste water, industrial wastewater and rainwa-ter and treating them to be carried back to wa-tercourses. By building sewage systems and providing drinking water supply will protect the population against the negative effects of the wastewater over the human health and the environment.

The paper presents experimental results of the manufacture of a lightweight aggregate from a waste (recycled clay brick from the demolition of buildings) and an industrial by-product (coal ash) using the unconventional microwave heating technique. The manufacturing process is based on the direct microwave heating at high temperature (over 1160 ºC) of the finely ground mixture of the raw material having incorporated a foaming agent (silicon carbide) with a role in expanding the material. The manufactured aggregate is a porous product with low apparent density and low thermal conductivity (below 0.80 g/cm3 and below 0.148 W/m·K, respectively), high mechanical strength (up to 8 MPa), low water absorption (below 7%), being suitable for the production of lightweight concrete. The specific energy consumption of the thermal process is very low (0.83-0.89 kWh/kg).

Nowadays pollution became one of the biggest problems of humanity. The effects caused by the rising of global temperatures have a negative influence on ecological and social changes. In this paper the need to reduce carbon dioxide emissions is presented. The analysis is aimed at quantifying the amount of CO2 from building heating, relative to the amount of emissions from the materials used in thermal rehabilitation, generated by producing and putting them into operation. The carbon footprint and energy consumption at each stage of the materials life cycle was determined using the OneClickLCA software.

Sustainable building development involves the use of environmentally friendly materials to reduce carbon footprint, energy consumption and costs. This paper presents natural, customary and innovative materials used in construction. Breathe brick used to filter air from existing pollutants into the atmosphere, Ferrock concrete absorbing carbon dioxide from the atmosphere, nanoparticle thermal insulating materials and metamaterials used in acoustic insulation are future solutions for sustainable development.

The experimental results of the manufacturing process of foam glass gravel using recycled glass waste (in very high ratio) are presented in the paper. The technique used for heating at 815-837 ºC of the raw material, composed of a powder mixture of glass, calcium carbonate (between 3-5%) as a foaming agent and borax (between 4.5-5.3%) as a fluxing agent, is unconventional based on microwave irradiation. The main physical, mechanical and morphological characteristics of the glass foam (low thermal conductivity between 0.087-0.110 W/ m•K, very high compressive strength up to 6.3 MPa, practically zero water absorption, pore size between 0.7-1.7 mm), similar to those industrially manufactured by conventional methods, are suitable for load-bearing thermal insulation under foundations or floorings, for insulation around the perimeter of buildings, underground heating pipes, underground tanks, as well as a filling material in the structure of road and railway constructions.

The Chernobyl events of 26 April 1986 and of Fukushima, on March 2011, reinforced the nuclear dimension of the EU energy policy by conducting a comprehensive exercise of resistance tests on nuclear installations in the European Union (and neighboring countries) during the period 2011 and subsequently with the adoption of the Council Directive 2014/87/EURATOM (2014) amending Council Directive 2009/71/ EURATOM (2009) establishing a Community framework for the safety of nuclear installations. This paper addresses some aspects specific to the Seismic Qualification Standards of the Electro-Energetic Command and Control Equipment for the Cernavoda Nuclear Power Plant, the main aspects of which include: a) Defining the seismic class of the equipment, b) Preliminary investigations, c) Seismic qualification, d) Final investigations, e) Conditions of seismic acceptance and qualification.

Sometimes there are reinforced concrete structures for which conventional computational methods are not sufficient to demonstrate their intended use. In-situ tests are conclusive to determine the ability of a structure to support additional loads, to determine its safety in the event of some design or construction deficiencies, degradation, or lack of design data. Thus, in-situ analysis validates the theoretical design approaches, in order to obtain data on the behavior of the studied elements. The aim of this paper is to present the groundwork and objectives of in-situ testing of reinforced concrete elements of buildings, with a view to possible structural assessments and to present the methods for carrying out the tests.

Determining the concrete compressive strength is an important issue for both existing and new constructions. Existing constructions, subject to retrofit and / or extension, require the determination of concrete compressive strength in specific elements, for the realistic and correct evaluation of the structure in terms of overall strength and stability. New constructions, on the other hand, may face situations when there are doubts about the quality of the delivered concrete, the casting operations or other technological or design flaws. The correct determination of the actual concrete compressive strength may be essential in evaluating the structural health and identifying the optimum design and technological solutions for the evaluated building. Non-destructive methods for determining the concrete strength are, by definition, minimally invasive methods, namely they do not affect the integrity of the structure. This paper provides a comparison between the combined non-destructive method and the destructive, classical method for compressive strength determination.

The notion of seismic risk is employed to describe the effects of earthquakes on social, economic and environmental aspects over a certain period of time and can be defined as the interaction of three parameters: seismic hazard, exposure time and structure vulnerability. A high seismic risk does not involve a high seismic hazard and vice versa. Disaster risk management is quantified by the application of appropriate policies and strategies necessary to prevent and reduce the risk, manage residual risk, thereby enhancing the resilience of the system. There are two strategic ways to reduce seismic risk: the improvement of emergency response and the adequate design of structures. Prevention is the most cost-effective solution and can play even the role of a driver for economic growth, and it is granted more attention in the disaster management cycle. Performance based seismic design involves the development of safety criteria in which the hazard is determined probabilistically as a function of the potential consequences of failure. Even if earthquakes cannot be accurately predicted, the disastrous consequences produced by human loss, economic and social damage can be minimized. In this paper, models of seismic risk mitigation programs for Turkey, Greece and Romania are presented.

The paper presents experimental results obtained in the manufacture of glass foams from packaging bottle glass waste, using the microwave energy. The glass foam as insulating material for construction is an advantageous alternative to existing building materials (e. g. expanded polystyrene) due to its superior resistance to mechanical stress, fire and humidity. The results have shown that the manufacturing techniques of glass foams in microwave field lead to products with physical, mechanical and morphological characteristics similar to those of industrial products made by conventional methods (low apparent density and low thermal conductivity, acceptable mechanical strength, closed pores). The advantages of applying microwave energy are eliminating pollution as well as reducing the specific consumption of energy. The originality of research conducted in the Romanian company Daily Sourcing & Research consists in the use of microwaves as an unconventional source of energy, worldwide only conventional heating methods being currently applied.

he today Romanian infrastructure, road and civil, evaluated both in terms of existing or identified need of structures (buildings of different importance class and with different functionalities, roads, highways, viaducts and bridges, etc.), represents an essential part, with major and synergetic role in the society life and evolution. As consequence, its preservation and future development are major topics of interest in order to ensure the progress of Romanian space as part of European Union and European Community. Identifying the optimum solutions and the best materials for this major goal should become priorities for all parties involved in the process: research and industry, academia, economic and political entities. Engineered Cementitious Composites (ECCs) are therefore mentioned as a new type of cement-based composites, with unique features and superior performances, which can be developed, tailored and adjusted according to specific needs, destination and structural design. This paper presents a general introduction of them, their potential towards a sustainable infrastructure and also a review of ECC development in INCERC Cluj, with local raw material and with respect to some proposed fields of application.

The paper presents the experimental results obtained for bending strength parallel to the fibers of a beam element made of hardwood (deciduous) glued laminated timber. At the same time, tests were carried out to determine the physico-mechanical characteristics of the wood specimens, in order verify the wood species.

Romania’s recent joining of the European family implies a fast upgrading of all evaluation references for every direction concerning life evolution and society development, in close correlation with the European ones. In accordance with the European strategies, implemented starting with 2000, sustainability is set as a key priority, governing all further development axes. Innovation, one of the foundation pillars of durability (environmental protection and non-renewable resources management) can be successfully implemented in all fields of activity. For instance, the path to a sustainable infrastructure could include innovative building materials, designed and developed by means of new technologies and of the latest information, as well as the use of additions (industrial waste / by-products), which could contribute to the improvement of their characteristics and performance. The aim of this paper is to present a general overview of the scientific demarches developed in the topic of Material Science, where innovation is achieved by identifying the re-conversion options for wastes and by-products from industrial processes, as mineral additions for cement-based composites.

In the case of repairs and restoration of historical buildings, the difficulty lies in preserving their value. It is important that the used materials to be as similar as the original ones, both in terms of composition and of application mode. The purpose of this paper is to present a synthesis of current analysis of techniques and methods for the used building materials in the historical buildings rehabilitation. Therefore, a bibliographic study has been carried out regarding the causes and types of degradation, the evolution in time of construction and building materials and the current analysis methods on their characteristics and the compatibility with the original substrate, too. The results of the theoretical analysis have shown that the degradation of historical constructions can occur as a result of natural causes (chemical, physical, biological and mechanical) or traumatic (fires, earthquakes and wars), resulting in strength and stability reduction of the structure, the loss of historical value due to deterioration of the architectural details etc.

The main problem with clay-based surfaces is the reduced resistance to water action. Literature does not indicate scientifically validated solutions for surface treatment. However, there are reports that indicate the benefits of impregnating surfaces with animal oils, vegetable oils, petroleum products, etc. The aim of this paper is to identify a solution for treating the surface of earth made bricks, in order to increase the degree of waterproofing and the resistance to water action, using local materials, specific to the western part of Romania. To achieve this, was used a surface treatment based on marble, lime, sand, clay, and water permeation reducing additive. On clay surfaces treated with this material, water vapor permeability and water penetration under wind pressure tests were conducted. The experimental results obtained indicated the optimal composition for the surface treatment material so that it does not crack upon drying, have good adhesion to the substrate, and improve substrate resistance to water action.

Over time, the building materials and the construction methods have evolved from simple to complex, from massive to slender. The study and development of rehabilitation and modernization methods for existent structures is a permanent concern of civil engineers and it is an activity which involves a team effort in order to preserve the specific characteristics of a certain building, but also to try and find new methods for modernizing the existing ones with respect to the efficiency and costs generated. The aim of this paper is to present the rehabilitation process of a building, the expertise and the analysis of the best options chosen for the modernization process.

The paper presents some experimental results of the research works developed in order to obtain innovative systems for corrosion protection of steel. The innovative nature of the research consists in the material type and the multilayered systems created and tested in laboratory and in situ conditions. Four recipes of an acrylic compound in aqueous dispersion, with ceramic microspheres, with a kaolin addition in different proportions were created and then applied on steel surfaces in 3 - layered systems. Also, there were presented the survey results of the systems mentioned above after their exposure to corrosive environments in accelerated laboratory conditions. The results of the survey, expressed by means of the adherence of the multilayered systems to steel surface, indicated a possible new merge between nanotechnology and the use of the natural resources, and a new possible direction for the use of kaolin in paint industry, in order to obtain a new type of coatings with a good reaction to the aggressive actions of the current climate manifested in various countries.

As it is well known, Romania and its capital, Bucharest, suffered building collapses, heavy damage and casualties in the 1940 and 1977 Vrancea earthquakes. The paper presents methods for the assessment of urban multi-hazard risks for emergency planning, using affordable tools. The scenarios for night and day time impact in the pilot study protected area have shown that: - Earthquake damage and casualties can be significant; for the seismic intensity I = VIII, a number of 63 buildings would suffer considerable damage, while for I = VIII½, the damage would affect 165 buildings, mostly low-rise structures. The number of heavy injured persons would be 29 and 64, while live loss will be 59 and 92, respectively, for the considered intensities. The damage would affect safety of living for about 1,809 to 3,061 people. - The scenario of climatic and hydrologic hazards is dominated by an extreme event of accidental flooding, in which the water cover could be as high as 2.5 m; - The terrorist blasting scenario has shown that, as the explosive quantity increases, the impacts would have great potential of damage, injured people and casualties.

The paper presents the framework and outcomes of a Joint Research Project between NIRD URBAN-INCERC, Bucharest, Romania and IEM Harbin, P. R. of China with the topic “Evaluation and Investigation of Seismic Risk Reduction Solutions for Buildings, Before and After Earthquakes”. The Project “RISKSOLVE” aimed at an exchange of information between experts from Romania and P.R. of China on legal framework for seismic design of buildings, seismic risk reduction and disaster prevention in each country. The study of sites with seismic risk, processing and evaluating the strong motion recordings was associated with the study of earthquake resistance and behaviour of building systems, correlation of damaged buildings patterns, properties and characteristics of materials and seismic site conditions. On the other hand, the design code solutions, as well as adequate retrofitting methods and construction details were evaluated, based on dynamic – seismic and static experimental tests on chosen solutions. The counterparts obtained promising results and information, useful to earthquake engineering researchers, in view of achievement of top scientific and technological results and future cooperation Romania – China.

The use of local natural materials in order to reduce the environmental negative impact of buildings has become common practice in recent years; such buildings are to be found in all regions of the planet. The high level of thermal protection provided by the envelope elements made from natural materials such as straw bale insulation, hemp insulation or sheep wool, and their lack of thermal massiveness require a more complex analysis on their ability to keep interior comfort without accentuated variations. This paper proposes a comparative analysis between different solutions for a residential building located near a Romanian city, Cluj-Napoca. The elements of the building envelope are designed in three alternative solutions, using as substitute to classical solutions (concrete and polystyrene, masonry and polystyrene), straw bales and rammed earth for enclosing elements. For this purpose there are conducted numerical simulations of heat and mass transfer, using a mathematical model that allows the analysis of indoor comfort, by comparing both objective factors (air temperature, operative temperature and relative humidity) and subjective factors, which are needed to define interior thermal comfort indices PPD and PMV. Finally, a set of conclusions are presented and future research directions are drawn.

Cement-based composites have proved, over the time, certain abilities of self-healing the damages (cracks and especially microcracs) that occur within their structure. Depending on the level of damage and of the composite type in which this occurs, the self - healing process (SH) can range from crack closing or crack sealing to the stage of partial or even complete recovery of material physical - mechanical properties. The aim of this paper is to present the general concept of Engineered Cementitious Composites (ECCs) with their unique properties including their self-healing (SH) capacity, as an innovative direction for a global sustainable infrastructure. The experimental steps initiated for the development in Romania of this unique category of materials, using materials available on the local market, are also presented.

Currently, a large number of seismic records, obtained over the years on instrumented buildings with various heights, located in urban environment, are available at global scale. The valorization of these records is important, as frequently no other information exists for the corresponding or neighboring locations. Several studies carried out recently have shown that the influence of the building can be separated, if certain characteristics of the structure-foundation-soil system are known. The paper presents the first results of an investigation concerning the usability of seismic records obtained in the past on stations located on buildings from densely urbanized areas in Romania. The reconsideration of the information provided by these stations could provide new perspectives on the spatial distribution of the ground motion parameters for the past earthquakes and, implicitly, a better understanding of the characteristics of seismic hazard in Romania.

In order to manage and control the stability of buildings located on difficult foundation soils, several techniques of soil stabilization were developed and applied worldwide. Taking into account the major significance of soil compressibility on construction durability and safety, the soil stabilization with a binder like lime is considered one of the most used and traditional methods. The present paper aims to assess the effect of lime content on soil geotechnical parameters, especially on compressibility ones, based on laboratory experimental tests, for several soil categories in admixture with different lime dosages. The results of this study indicate a significant improvement of stabilized soil parameters, such as compressibility and plasticity, in comparison with natural samples. The effect of lime stabilization is related to an increase of soil structure stability by increasing the bearing capacity.

The Alto Douro Wine Region, located in the northeast of Portugal, a UNESCO World Heritage Site, presents a relevant tabique building stock, a traditional vernacular building technology. A technology based on a timber framed structure filled with a composite earth-based material. Meanwhile, previous research works have revealed that, principally in rural areas, this Portuguese heritage is highly deteriorated and damaged because of the rareness of conservation and strengthening works, which is partly related to the non-engineered character of this technology and to the growing phenomenon of rural to urban migration. Those aspects associated with the lack of scientific studies related to this technology motivated the writing of this paper, whose main purpose is the physical and chemical characterization of the earth-based material applied in the tabique buildings of that region. Consequently, an experimental work was conducted and the results obtained allowed, among others, the proposal of a particle size distribution envelope in respect to this material. This information will provide the means to assess the suitability of a given earth-based material in regard to this technology. The knowledge from this study could be very useful for the development of future normative documents and as a reference for architects and engineers that work with earth to guide and regulate future conservation, rehabilitation or construction processes helping to preserve this fabulous legacy.

The paper evaluates the urban heritage situation at almost four decades after the Bucharest, March 4, 1977 earthquake disaster, followed by a razing of the present Civic Center area and a large-scale remodeling project. The first results of the URBASRISK Project (2012) are presented as a contribution to a new multi-hazard paradigm to cope with European urban scale threats, especially in heritage areas, with a case study of a historic zone now designated as protected area. The cultural and utility value was identified and graded on specific scales for further analysis and mapping. For this phase of study some data of 1977 were adjusted to express the vulnerability by the Mean Damage Degree, GA, with a possibility to make corrections after visual inspection. The URBASRISKdb geodatabase was created for storing the attributes of the buildings. The basic source, i.e. the ESRI World Street Map layer, was verified against satellite, aerial and street views freely available online from various providers. The final version of the map was obtained by also considering information obtained by field visits.

The paper presents the content, rationale and preliminary results of a study of the seismic response of Tropaeum Traiani monument, at Adamclisi, in Southern Dobrudja. It is a unique structure of its kind in Romania and the only Roman Empire trophy having kept the original core and a large number of stone parts. There is neither a professional assessment of the seismic source and motion size that caused the upper part overturning, nor an analysis of the monument’s dynamic response, based on the remnant pieces. The research aims at deriving the earthquake resisting capacity of specific sections based on dimensions and detailing of stone components. In order to obtain some input accelerations likely to initiate oscillation, shearing or sliding and overturning of the monument specific parts, a reverse technique is considered. The preliminary study allowed the assessment of oscillation amplification patterns at different heights, indicating the direction of collapse of upper pieces. The data are in a good correlation with some previous INCERC data about the particular directivity of some Vrancea motions in Dobrudja in 1990 and with places of stone parts unearthing. The estimation of a range of historical time for the destructive earthquake is also a goal.

The pounding between adjacent buildings can cause both architectural and structural damages. The paper presents some aspects related to the Vrancea seismic motions pattern, a review of observed damages after a strong earthquake due to pounding of buildings in Romania, a few causes of pounding, an analytical and numerical modeling study. For the behavior of buildings under structural pounding, an analysis with and without consideration of soil-structure interaction is done.

The authors contributed during a quite long period of time to the development of comprehensive and flexible system of estimating seismic intensity on the basis of instrumental (accelerographic) data on earthquake ground motion. The system makes it possible to determine for a record, according to needs, global intensities, intensities corresponding to definite frequencies, intensities averaged upon a spectral band, continuous or discrete intensity spectra. Moreover, the intensity measures developed may rely, according to choice, on different outcomes of processing of primary instrumental data. A problem to which the paper is devoted is represented by the calibration of an important parameter, namely the logarithm base adopted in view of conversing instrumental information to intensity measures. After the attempts of the past, new sources are used this time to solve the problem. Alternative solutions are examined and discussed in this view.

As a result of the global warming, notable changes in the climatic regime of Romania were observed in the last 40-50 years by increasing of the maximum temperatures and decreasing of the minimum temperatures characteristic for each season. This paper makes reference to an experimental research regarding the actual severity of the Romanian climate and its effects toward some performant anticorrosive coatings applied on steel. Such performant anticorrosive protection systems were exposed in situ – marine and alpine environment - and in parallel, aiming to simulate the severe climatic actions through laboratory accelerated environments - neutral salt fog, condensation and temperature variations. The graphical representation and the interpretation of the adhesion to the steel surface by means of the variation of the class into which the paint was framed after performing the cross-cut test during the exposure provided information concerning a new possibility to predict the evolution of the degradation of the paint, by means of this characteristic experimentally determined.

During the period 1600-1700, the first works with parquet elements at Versailles Palace were performed, but the high cost has made that the wooden floor to be an exclusivist product for a long time. Currently, in the last 30 years, the most innovations in flooring industry were aimed to improve the technological process, the easing of work, to reduce the losses of raw materials and to reduce the production costs. The experimental research conducted worldwide has shown that the wood processing technology, up to the flooring finite element, plays an important role in achieving a superior quality and durability and that the finishing systems have to be applied depending on the conditions of the area of use. This paper is a comparative study regarding the physico-mechanical characteristics for five types of wood flooring manufactured and marketed in Romania. In the experimental research, there were analyzed: the behavior of the floor assemblies under linearly distributed and concentrated loads, the thermal insulation characteristics and the slip resistance. The experimental results have shown that these characteristics are influenced by the wood species, the type of product (massive one or subjected to stratification technological processing), the thickness of lamellar flooring elements, and the chosen finishing method (varnishing, oiling).

The paper presents experimental research performed on fiber reinforced concrete slabs. For the preparation of the concrete elements, three different dosages of polypropylene fibers were used. The size of the specimens and the test methodology were established according to the SR EN 14488-5 - Testing sprayed concrete. Part 5: Determination of energy absorption capacity of fiber reinforced slab specimens. The slabs were tested in the Central Laboratory of the Faculty of Civil Engineering, Cluj-Napoca, using a flexural frame and the Advantest 9 console, capable of applying load in displacement control. Using the area under the load-displacement diagram, the energy absorption capacity of the fiber reinforced slabs was determined, at the age of 28 days.