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Within the last decade, much attention has been focused on determining viable techniques for producing sustainable asphalt mixtures and minimizing fuel use and greenhouse gas emissions. Thus, warm mix asphalt (WMA) has become a topic of significant interest among road specialists as it offers a potential solution for reducing the environmental impact of the asphalt mixtures due to the decreased temperatures they require for mixing and compaction compared to hot mix asphalt (HMA). The present study is focused on the Life Cycle Assessment (LCA), according to a “Cradle-to-Gate” approach, of hot mix asphalt and warm mix asphalt prepared with locally available materials and different warm mix additives such as organic additives, chemical additive, and synthetic zeolite. For the analysis of the environmental impact of the warm mix asphalts was used a dedicated software for modeling and evaluating the LCA. The WMA prepared with chemical additive or organic additive led to a decrease of the environmental impact, in the production phase, compared to HMA. The study reveals that the raw materials extraction has the greatest impact on the environment in all studied cases, followed by the actual production phase of the asphalt mixture. For WMA produced with additives there was a decrease in the global impact on the environment compared to HMA.

The building sector continues to register a significant rise in energy demand and environmental impact, notably in developing countries. A considerable proportion of this energy is required during the operational phase of buildings for interior heating and cooling, leading to a necessity of building performance improvement. A holistic approach in building design and construction represents a step to moderate construction costs in conjunction with reduced long-term operating costs and a low impact on the environment. The present paper presents an experimental evaluation of the energy efficiency of a building under real climate conditions, the building, which represents a holistically designed modular laboratory, is located in a moderate continental temperate climate, characteristic of the south-eastern part of the Pannonian Depression, with some sub-Mediterranean influences. Considerations for the holistic design of the building, including multi-object optimization and integrated design with a high regard for technology and operational life are described. The paper provides a genuine overview of the energy efficiency response of the building during six months of operational use through a monitored energy management system. The energetic analysis presented in the paper represents an intermediary stage as not all the energetic users were installed nor all the energetic suppliers. However, the results showed a reliable thermal response in the behaviour of recycled-PET thermal wadding used as insulation material in the building and for the intermediary stage in which the building has only secondary energy users, the energetic balance proves its efficiency, keeping the buffer stock of energy high values over 90%.

The paper summarises the main results of the full scale tests on beam-to-column joints, carried out within the experimental programme of COPERNICUS “RECOS” European Research Project, in the Laboratory of Department of Steel Structures and Structural Mechanics of the “Politehnica” University of Timisoara. Two series of six double-sided joints with three different beam-to-column connection typologies have been tested under symmetrical and anti-symmetrical cyclic loading, respectively.

In EN 1994-1-1, design rules are given for the evaluation of the mechanical properties of structural steel-concrete composite joints (rotational stiffness, resistance and ductility). The proposed rules are based on the component method as recommended in EN 1993-1-8 and, in particular, rules for components specific to composite joints are provided in EN 1994-1-1. The main weakness of the rules as presently proposed is that they are only covering cases where composite joints are subjected to shear forces and hogging moments while, in practice, such joints can be subjected to other loading conditions such as sagging bending moments, cyclic loadings, combined bending moments and axial loads, elevated temperatures etc. It is the reason why, during the last decades, researches have been conducted in this field with the objective of improving/extending the rules presently recommended in the Eurocodes. This present paper highlights the main outcomes from part of these researches conducted at Liege University and at University Politehnica Timisoara which could be seen as proposals for future improvements of the beam-to-column provisions in Eurocodes in general and of Eurocode 4 in particular.

The standard push test specimen in the current version of Eurocode 4 does not provide any information on what modifications should be made when profiled steel sheeting is introduced. Whilst the lack of information was intended to encourage innovation, this has sometimes lead to test results implying that stud connectors possess a lower resistance and ductility than assumed in current Standards. From full-scale beam and companion push tests in Europe, it has been shown that modifying the push test through the introduction of a normal force to the face of the test slabs provides comparable load-slip performance to that encountered within a beam. Within the work programme for developing the second generation of Eurocodes, this paper presents part of the background to Sub-task 1 of SC4.T3, whose aim is to develop an improved push test for Eurocode 4 when stud connectors are welded within profiled steel sheeting.

Origanum vulgare L. var. aureum is an aromatic medicinal plant belonging to the Lamiaceae family, rich in essential oils and antioxidants. Its specific chemical composition represents an important source of biologically active principles with diverse applications in food products and nutraceuticals. The aim of this study was to determine the differences between chemical composition of volatile oils, phenolic content and antioxidant activity of different plants parts: leaves, flowers, and stems. Essential oils from leaves and flowers had similar compositions with only few differences between γ-terpinene and trans-ß-ocimene. Total phenolic content and antioxidant activity were determined for the hydro-alcoholic extract obtained from post-distillation oregano waste material. The total phenolic content was determined using Folin-Ciocalteu reagent and varied from 3173 to 6522 mg GAE/L. The major compounds identified by HPLC were syringic acid, pyrocatechol, and catechin. Furthermore, all extracts showed high antioxidant activity, ranging from 31.3 to 44.5 mg GAE/L, with an inhibition percent varying from 63.1 to 88.6%.

Eccentrically braced frames (EBF) in steel and composite solution are very well suited structural assemblies for buildings in areas with high seismicity. Due to their good energy dissipation capacity, they can undergo important lateral deformations by plastic hinge formation in the dissipative element (link element) without impacting the structural integrity of the system. The dissipative link elements can be short, medium or long (according to modern design norms, such as Eurocode 8), based on the ratio between shear force and bending moment. If the dissipative element length is smaller than 1.6(Mpl/Vpl) [mm], it is considered to be a short element and is predominantly subjected to shear. The links can be realized on steel solutions or composite with the concrete slab. However, the steel behavior is assumed for composite link. The current article presents the results of extensive numerical testing based on experimental results on the behavior of composite EBF with short link elements subjected to seismic-like lateral loads. The results will present the main differences in strength, stiffness and ductility between the responses of steel and composite EBFs. Finally, a parametrical study will show the influence of link length, influence of number of stiffeners and of the web slenderness.

Building sector focuses on surpassing challenges linked to energy efficiency and mitigation measures related to greenhouse gas emissions, in consequence, it needs to improve building performance in the interest of decreasing impact over environment. Buildings with reduced long-term operating cost, environmental-friendly and moderate construction costs can be achieved only by multi-object optimization and cross-disciplinary analysis, embodying a holistic approach. Following the main principles of the holistic sustainable design approach, the paper presents a sustainable experimental modular laboratory involving various strategy in regard with sustainable building, as resource, cost and material efficiency, health and well-being, environmentally conscious design, life cycle design, modular design, reusable/recyclable element, environment-friendly demolition method, safety design, consideration of life cycle cost, materials cost and waste disposal cost. Besides the installation of renewable energy sources and conservation of energy, the holistic construction of laboratory included also an integrated design with consideration for technology, operation and maintenance, which involved the implementation of a monitored energy management system. The system provides an accurate overview of the building’s performance during operational phase. Although the monitoring is still in an incipient phase, recordings showed promising results regarding the behaviour of recycled-PET thermal wadding used for insulation and indoor comfort conditions.

Wedge or tapered foundations of buildings, which have greater top cross-sections than bottom ones, are not often considered as a design option due to their shape. However, precast wedge foundations could be considered as “quick foundation systems” in case of light structures which should be rapidly installed. Similar to tapered piles, this foundation shape can offer besides the bottom base resistance, a good lateral contact between the inclined concrete faces and the surrounding soil. The paper presents the experimental results of two wedge foundation specimens subjected to axial compression tests conducted in accordance to actual standards. The results recorded on sites are presented under the form of pressure-settlement diagrams and are compared with similar values recorded for usual prismatic foundations. The study is completed by an environmental impact analysis made on the two systems along with potential benefits and loads, beyond the system boundary, at the foundations’ end-of-life.

The paper focuses on the investigation of the potential environmental impact related to the production of several types of bituminous mixtures containing different dosages of Reclaimed Asphalt Pavement (RAP) and Rejuvenator (Rej). All materials used in the presented study are specific and generally used for pavements in Romania. The RAP material was considered as an inert material and it was used in three dosages (25%, 50% and 75%). For the bituminous mixture produced with 50% RAP material, a rejuvenator consisting in a mixture of vegetal oils was used in three dosages of 0.2%, 0.4% and 0.6% by mass of RAP material. A total of seven types of bituminous mixtures were considered including one ‘conventional’ mixture produced with virgin materials and used as reference. The Environmental Impact Assessment was estimated for the production process of the analysed bituminous mixtures, by using Eco-indicator 99 method within SimaPro software. The results prove that the addition of RAP material leads to a net decrease of the energy use and environmental impact. Besides, when rejuvenators are used in this process, they can affect the energy balance and reduce the difference in environmental impact.

Eccentrically braced frames are well known for their capacity of dissipating seismic energy by plastic hinge formation in the so called ‘link elements’, which represent the dissipative devices of the eccentrically braced frame. The link element can be short, which means it will be mainly subjected to shear forces; long being mainly subjected to bending moment or intermediate in length subjected to a combined action of shear force-bending moment. The current study is focused on the calibration of existing experimental results with numerical finite element models of steel eccentrically braced frames with short link elements and a subsequent parametrical study considering different link lengths and multiple stiffeners along the link web panel.

An important segment of the Romanian urban population, similar to other Eastern European countries, lives in collective residential apartment buildings made using large prefabricated concrete panels. Most of these structures were built between 1960 and 1989 and present major issues concerning aesthetical aspects, lack of internal space, problems related to thermal comfort and, last but not least, weak energy efficiency. The presence of flat roofing system, generally with hydrothermal faults, represents an additional problem which leads to deficient living conditions of the last-storey inhabitants in many cases. Besides other ways of improving the conditions of such apartment houses, the over-roofing is welcome in order to both increase the habitable area and provide adequate roofing for the building. This article presents three types of over-roofing structural solutions, in two solutions, based on intensive use of steel, using (1) hot-rolled steel profiles, (2) rectangular hollow sections and (3) cold-formed steel profiles, respectively. In order to determine the optimum over-roofing system, the study analyses the structural design possibilities and particularly the connection between the new and old structural elements.

Steel façade systems follow the actual tendencies in construction offering robust and sustainable solutions, able to answer to actual conditions and to offer adequate interior thermal comfort. The modern sandwich panels provided by the current façade system producers combine the required thermal resistance by varying the thermal insulation material and its thickness with the required structural demands. In addition, the façade layer could be over-coated with different materials, thus offering the required architectural aspect. Other advantages of the systems rely on industrialized prefabrication, fast installation and adaptability. They could also be disassembled and reused. The study presents an analysis of some envelope solutions existing on the market for buildings made of thin-walled cold-formed steel structural systems. The study consists in an annual energetic analysis of Mineral Wool (MW)-based system and a more sustainable recycled-PET thermal wadding-system. The analysis includes for input the own-produced energy by power grids and additional national grid energy while for output heating / cooling and electric appliances are considered. The study is completed by a life-cycle environmental analysis. The study revealed that when the thermal insulations have nearly the same U-value, the environmental impact of the recycled-PET thermal wadding-based system is smaller than that of MW-based system. Although the environmental impact of the recycled-PET thermal wadding is higher in the production stage, the insulation quantity of the material needed for PET-recycled thermal wadding to accomplish the required thermal resistance is much smaller than that of MW. Moreover, the original material for the recycled-PET thermal wadding is 100% recycled which implies a certain benefit of circularity to the material. The study also proves that the glazing ratio has also an impact on the thermal performances of studied systems: by reducing the overall glazing ratio of the envelope, the solar gain drops significantly, which leads to an increased heating energy demand, in order to meet indoor thermal comfort.

The slim-floor building system is attractive to constructors and architects due to the integration of steel beam in the overall height of the floor, which leads to additional floor-to-floor space, used mostly in acquiring additional storeys. The concrete slab offers natural fire protection for steel beams, while the use of novel corrugated steel sheeting reduces the concrete volume, and replaces the secondary beams (for usual spans of steel structures). Currently the slim-floor solutions are applied in non-seismic regions, and there are few studies that consider continuous or semi-continuous fixing of slim-floor beams. The present study was performed with the aim to develop reliable end-plate bolted connections for slim-floor beams, capable of being applicable to buildings located in areas with seismic hazard. It is based on numerical finite element analysis, developed in two stages. In a first stage, a finite element numerical model was calibrated based on a four point bending test of a slim-floor beam. Further, a case study was analysed for the investigation of beam-to-column joints with moment resisting connections between slim-floor beams and columns. The response was investigated considering both sagging and hogging bending moment. The results are analysed in terms of moment-rotation curve characteristics and failure mechanism.

In EN 1994-1, design rules are given for the evaluation of the mechanical properties of structural steel-concrete composite joints (rotational stiffness, resistance and ductility) based on the component method offered in EN 1993-1-8 and adding specific components for composite joints. These rules cover only the situations for the joints subjected to shear forces and hogging moments. However, during the last decades, researches have been conducted on the behaviour of composite joints subjected to different kind of actions such as sagging bending moments, cyclic loadings, combined bending moments and axial loads, elevated temperatures etc. with the objective of improving/extending the rules presently proposed in the Eurocodes design rules. As an outcome of the Technical Committee 11 of the European Convention of Constructional Steelwork (ECCS) dedicated to the behaviour of composite structures, a publication summarising these recent developments and their main outcomes is under finalisation. Within the present paper, it is proposed to highlight these main outcomes which could be seen as proposals for future improvements of the beam-to-column provisions in Eurocodes in general and of Eurocode 4 in particular.