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Tactile interaction between humans and elements in the built environment, such as furniture, is often underappreciated. The aim of this study was to objectively evaluatethermal propertiesof ten tabletop materials as well as user perceptions of those materials after use. Sixteen participants tested ten materials in a randomised order.Infrared thermographywas used to determine tabletoptemperature distributionand change. Materials with lowerthermal effusivity(wood-based materials) in general reached higher surface temperature differences after 15min of contact and were rated as more pleasant to touch, more suitable for writing, and more liked for everyday use. Participants’ sex and forearm mass had no effect on the temperature after contact. Participants gave the highest ratings to the appearance of oak-based materials. Surface treatment affected subjective evaluation of the materials. The tabletop made of lacquered solid wood had the most favourable thermal and user-rated characteristics.

I denna undersökning granskas perspektivförändringar i polisens svenskspråkiga förundersökningsprotokoll, upprättade i Finland. Protokollet består bland annat av samtliga involverade personers förhörsberättelser, vilka polisen sammanfattar till en redogörelse. I redogörelsen ingår också polisens egna fältanteckningar som gjorts på brottsplatsen. Redogörelsens uppgift är bland annat att ge polisen och rättsväsendet en sammanhängande och koherent beskrivning av brottshändelsen. Redogörelsen är med andra ord en betydande text under en eventuell rättegång, inte minst med tanke på de involverade personernas demokratiska rättigheter. I undersökningen ligger två specifika problem beträffande förundersökningsprotokollet i fokus. Det ena är att det finns variation i det sätt på vilket förhöret dokumenteras. Det andra är att skrivprocessen från förhörsberättelse till redogörelse involverar komplexa omskrivningar och perspektivbyten, i vilka det finns en fara för att den förhörhördas röst försvagas på vägen. Det övergripande syftet med undersökningen är att reda ut om det sätt på vilket förhöret dokumenteras påverkar perspektivet i redogörelsen. Mer specifikt utreds i vilken grad den misstänktas röst kan anses förmedlas i det färdiga protokollet, och vilka perspektivmarkörer som eventuellt kan resultera i att perspektivet förändras. Ett underliggande syfte är att jämföra de perspektivförändringar som sker i svenskspråkiga förundersökningsprotokoll som är upprättade i Finland med de perspektivförändringar som sker i protokoll upprättade i Sverige, för att kunna belysa eventuella nationella skillnader. Denna jämförelse baserar sig på resultat av Linda Jönssons (1988) och Gunilla Almström Perssons (2009) tidigare undersökningar av förundersökningsprotokoll upprättade i Sverige. Materialet i denna undersökning består av åtta förundersökningsprotokoll, varav fyra är upprättade vid polisinrättningar i Österbotten och fyra vid Ålands polisenhet. Undersökningens teoretiska referensram består av en kombination av Lennart Hellspong och Per Ledins (1997) syn på det ideationella perspektivet i deras systemisk-funktionella lingvistiska teori, Linda Jönssons (1988) syn om att perspektivet i förundersökningsprotokoll förmedlas genom återgivna citat och Gunilla Almström Perssons (2009) teori om att perspektivet i förundersökningsprotokoll bland annat förmedlas genom den narrativa berättelsens upptrappning och genom ett centrum?periferi-tänkande. Den undersökningsmetod som utarbetats för detta ändamål har jag valt att kalla för strukturell perspektivanalys av en realistisk berättelse. Metoden kan beskrivas som en öppen innehållsanalys, vars resultat kvantifieras och slutligen jämförs. Undersökningens resultat påvisar att exempelvis passiveringar, rörelseverb, metaforer, citat och värderingar kan fungera som perspektivmarkörer. Dokumentationssättet verkar påverka perspektivet till en viss grad och kvantifieringen påvisar att ca 24 % av den misstänktas originalutsaga kvarstår i hens utsaga, vilket utgör ca 2,4 % av redogörelsen. Resultatet är förhållandevis likt de resultat Jönsson (1988) och Almström Persson (2009) har kommit fram till gällande protokoll upprättade i Sverige. Nyckelord: förundersökningsprotokoll, förhörsberättelse, redogörelse, kontext, rekontextualisering, perspektiv, perspektivmarkör, perspektivförändring, röst, rättslingvistik

The construction industry across Europe is facing major challenges in achieving energy efficiency targets, in particular for Near Zero Energy Building (NZEB), but they are also experiencing a digital revolution, with Building Information Modelling (BIM). The Fit-to-NZEB, Net-UBIEP (Horizon 2020) and BIMzeED (Erasmus+) projects intend to improve the human-capital basis of the construction sector, which is identified as a strategic initiative by the European Commission, acting on Higher Education Institutions (HEIs) and Vocational Education and Training (VET) systems in Europe. These projects support the construction industry, through education and training to upskill on technical innovation and digitalization. Not only is digitalisation trainings an important focus for the progression of the construction sector, but providing a low carbon efficient economy requires the integration of BIM with nZEB design and development approaches. At EU level, the challenge remains to introduce relevant standardised environmental and energy efficient learning topics into mainstream training and degree courses at HEIs & VETs. This paper analyses the current situation in the Architecture, Engineering and Construction (AEC) industry in several EU countries and provides a possible solution for the abovementioned problems in the field of NZEBs and BIM. The analysis of current formal and informal educational programs in the AEC industry revealed that topics related to the deep energy renovation (DER) and NZEBs are not adequately covered, or not covered at all, resulting with a lack of qualified workers and professionals. Another major problem detected in the conventional project delivering is an absence of integrated or interdisciplinary approach between all the stakeholders. This paper will show how the competences of construction stakeholders in the field of NZEBs and BIM can be increased.

Reinforced concrete is a widely used structural material. Usually, steel is the material used for reinforcing elements. Most important problem with using steel is the fact that it is susceptible to corrosion, which significantly affects durability of a structure. Fiber reinforced polymer (FRP) materials can be used instead of steel to avoid corrosion. FRP can either be used for repair of existing, or design of new structures. Different materials can be used to form FRP reinforcement, each having their own modulus of elasticity and strength, but all of them behaving elastically until failure. Usually, stiffness of steel is greater than stiffness of FRP bars, making FRP reinforced elements more sensitive to deflections. Hybrid FRP – steel reinforced members mitigate insufficiencies of both elements reinforced only with steel and elements reinforced only with FRP. Behaviour of hybrid reinforced members depends on not only the amount of each type of reinforcement, but also on its distribution inside a section. Since ductility of sections is important for overall structural response, a more detailed analysis of ductility is given in this paper. Different concrete sections with the same bending moment capacity are analysed. Only rectangular sections under bending moment are considered in this paper. Concrete class, width and height are all kept the same, while the rebar material, amount and layout are varied. Bending moment – curvature diagrams are obtained and compared with each other, as well as section stiffnesses.

To achieve the goals set by the European Union (EU) in terms of energy savings and decrease of the greenhouse gas emissions, the member states of the EU obliged that they would increase the number of the Nearly Zero Energy Buildings (NZEB). That increase has to be accomplished not only by building new NZEBs but also by deep energy renovations of old ones. One of the criteria to fulfil NZEB demands is to ensure the airtightness of the building, which is usually tested by an air pressurisation test. As there will be a great number of buildings which must undergo the testing in the near future, it is important to find a way to speed up the testing for the multizone buildings. This paper presents research based on the results of building zone airtightness estimations based on a fan pressurisation test by the so-called Blower Door system. It is a part of research whose goal is to develop a predictive model of the air-change-rate for a multizone building based on randomly tested zones. The paper describes a connection between the airtightness of tested building zones and elements which make up these zones. This research is crucial as a starting point for the development of the predictive model in order to define the parameters that affect these measurements. Statistical analysis was performed not only for the analysed results but also for an exploration of the connection between the zone elements and the zone’s airtightness as well. The paper presents a hypothesis based on the abovementioned research and proposes further research for the future development of the model.

It is now more obvious than ever that the only option for the development of the built environment is a sustainable and environmentally responsible one. In the field of building materials, especially in concrete technology, there are many studies that deal with alternative raw materials, such as by- products, recycled materials or natural resources that are not fully exploited. However, with the alternative materials, alternative durability challenges may also arise. More so, some of the known durability challenges may re-emerge in alternative forms. Alternative materials have different chemical and physical properties compared to a classical system. Different reaction products, different pore structure, electrical resistivity or tortuosity of the pores can lead to different behaviour of the materials and their degradation mechanisms. To predict and control the durability of alternative materials in the environment, a complete understanding of their microstructure is of utmost importance. In the present work, some examples of developed alternative binders based on local materials are presented. Among others, binders based on high cement replacement, binders based on calcium aluminate and alkali-activated binders are discussed. Among the degradation mechanisms, chloride penetration, corrosion and carbonation and their specific mechanisms with alternative binders are addressed.

Despite numerous national regulations, it has been shown that the traditional practice when insulating building envelope is insufficient if not enough attention is given to thermal bridges. Heat losses through thermal bridges are much higher than the heat losses through the surrounding area. Because of that, the thermal bridges are accompanied by lower surface temperatures, resulting in the higher risk of water vapour condensation and the formation of mould, and ultimately building damage. Therefore, much attention should be given to the design of thermal bridges and ultimately, its construction. This paper deals with the impact of thermal bridges on the outer building envelope of the ventilated façade system of the first ECO-SANDWICH® house in Croatia. The house is built in Koprivnica as part of the Green Zone project. It is designed according to the standards for passive houses using innovative, ventilated Eco-sandwich® façade panels, designed at the Faculty of Civil Engineering, University of Zagreb. All the details in this paper are modelled as two -dimensional, according to the HRN EN ISO 10211 standard. The numerical calculation is carried out by software specialised for the heat flow and thermal bridge calculation – Flixo. The output result, linear heat transfer coefficient (Ψ), which quantifies the impact of linear thermal bridges on the one -dimensional heat flow, is analysed by variation of parameters, such as thermal insulation thickness. Finally, the numerical results are compared with the results obtained by default values of linear thermal bridges according to the standard HRN EN ISO 14683. This comparison is made to show the error between the results obtained by the numerical calculation and the default values, which are typically taken in the traditional calculation of heat losses in buildings.

Polyurethane (PU) foams are widely used in building structures. Due to their good thermal and sound insulation properties, PU foams are often applied in the production of façade systems as a non-structural component. In addition, they are commonly used in structural load-bearing components, e.g. as a core material in composite sandwich panels. In order to be used in load-bearing structures, it is necessary to know their mechanical properties. The main mechanical properties of PU foams are influenced by many parameters such as density, temperature, anisotropy, loading condition, etc. In this paper, the influence of density on tensile and compressive properties of PU foam is presented. Therefore, the uniaxial tension and compression tests according to the International Standards for six different densities were performed. Based on the test results, the influence of density on tensile and compressive strength as well as compressive modulus of elasticity is reported.

In Croatia, a great number of buildings are built in masonry. The majority of them were built before the development of seismic codes and a lot of them are vernacular, unreinforced structures. As a result, many of these buildings need to be evaluated and, if needed, strengthened. Today, codes and guidelines for the evaluation and retrofitting of existing masonry structures do exist but are not very comprehensive and require a lot of engineering subjective judgment to implement. Furthermore, the problem lies in the complexity of implementing retrofitting methods since most of the masonry buildings are in use (private or public) during the strengthening. Besides that, a great number of buildings in Croatia (i.e. City of Dubrovnik) and around the world built in stone masonry have a great heritage value so the requirements made by conservators play a part in the methods used as well. An overview of the most commonly used methods of seismic analysis and strengthening are presented in this paper. The main objective of this paper is to comprehend, gather and compare different state -of-the - art principles of seismic retrofitting of structures focusing on stone masonry. Different approaches are analyzed and compared in order to get closer to a unified method of evaluation and strengthening of existing structures.

The topic of this paper is numerical modelling of concrete beams reinforced with FRP reinforcement and comparison of the results with experimental ones. Numerical models of concrete beams subjected to bending until failure, reinforced with steel, GFRP or CFRP reinforcement have been made. Thefinite element method was used, and the models were made in Midas FEA software. Concrete is modelled by the total strain crack theory. A smeared cracks model was used. Steel is modelled as Von Mises material, while FRP behaviour is linear elastic. The interface between the reinforcement and the concrete was also modelled, as bond – slip function. The goal is to compare the results obtained by numerical models with the results obtained by experiments, which were elaborated in previous work of first author. Experimental results contain material properties of used materials: concrete, steel and FRP reinforcement and bond slip behaviour between reinforcement and concrete. The results showed that it is possible to obtain similar results obtained by experimental research, but very important is knowledge of material behaviour and modelling of it.

NORNAs 46:e symposium ordnades i Tammerfors den 21–23 oktober 2015, med temat Namn och identitet. Temat är brett, och artiklarna i den här volymen behandlar det från olika infallsvinklar. Resultatet är, som själva symposiet, en varierad artikelsamling som knyter ihop namn och identitet på ett intressant sätt.

The construction sector has an enormous impact on the global environment, national budgets and community and therefore the obligation to constantly improve its performance. LCA in this context is becoming an unavoidable tool in trying to achieve more sustainable practices. In case of structures with really long life cycles such as bridges this becomes even more important especially because of many maintenance and repair procedures that will occur through its lifespan. When a need about repair incures the most common way to come to a reasonable decision about the repair method is to perform a life cycle cost analysis (LCCA) and determine which option will be most cost effective during the whole life cycle of a structure. A case study in which LCCA was performed on 11 overpasses which constitute the largest Zagreb junction will be analyzed in this paper. The emphasis was on awakening owner’s awareness about pro-active approach to management of the structures. This case study became a foundation for developing an analytical model for selection of optimal repair method which will also be shortly presented in this paper.

In July 2019, Croatian energy market operator had 38 contracts for electricity from renewable energy sources (RES) with power plants under construction. 50% of these were for biomass power plants and represented 19% of planned install power. While the increasing number of plants creates more wood biomass ash (WBA) to manage, landfilling prices are rising and although this research is done locally, the problem is global. In 1882 the first coal fired power plant was built in London as a project by Thomas Edison. The first high-volume coal fly ash recycles in concrete was done to repair a part of the Hoover Dam in 1942. In the 80s, with first legal guidelines and construction expansion, recycling of coal ash in concrete become routine. Biomass has been used as heat energy since people learned to control fire, but when speaking about RES, we refer to modern biomass combustion systems that started to sprout in developed countries during the 90s. Extensive research on the characterization of WBA and its influence on concrete properties has been going on during the last few years. Research has also been done on the impact of recycling for other fields trying to find a quicker solution for ash disposal this time. For now, we know that WBA can be used as an active (replacement of cement) or inactive (filler, sand substitute) concrete component. Fly WBA is usually compared with coal fly ash, but ash properties vary depending on many factors - from type and growth conditions, through the combustion system, to ash management on site. The link between power plants and the concrete industry should be established through consistency and quality control. This could be achievable by establishing ash pre-treatments. Treated ashes could be a more reliable material for larger scale cement replacement.

Renewable energy, together with environmentally-friendly materials, gives us an insight into a sustainable future – one where reliance on fossil fuels and greenhouse gas emissions are minimised. The leading source of renewable energy in the EU are biomass fuelled power plants. Among different types of biomass, wood has the widest application while holding the majority share with 59% of all renewable energy sources. Nevertheless, combustion of 1 tonne of wood biomass generates approximately 3% of wood biomass ash (WBA), resulting in large amounts of waste. WBA management is an issue in need for prompt solutions, to avert further endangerment of the environment as well as disposal costs. Using WBA as partial cement replacement in cement composites is considered to be a feasible application. However, the fluctuating chemical composition of WBAs somewhat differs from coal fly ash, already acknowledged as a supplementary cementitious material. Due to the aforementioned difference and lack of standards and guidelines for WBAs application in cement composites, its wider application is still limited. Therefore, the main goal of this research was to quantify the acceptable amount of fly WBAs in concrete, while considering the chemical composition of different fly WBAs. Three WBAs utilized in this research were collected from different power plants located in Croatia, that exploit untreated wood chips as fuel while applying different combustion technologies. Six concrete mixtures were prepared with ash content of 15% and 20%. The impact of each WBA on concrete properties was analysed based on the determined compressive strength and modulus of elasticity. Differences between particular WBAs have been reflected on the properties of concrete mixtures.