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Many of the current European Member States regulations on energy saving in buildings seem to follow North European trends that call for high insulation of the envelope. However, this kind of set-up overlooks some specific elements that are necessary to build typical buildings in warmer climates. Thermal inertia on the internal surface of the envelope has traditionally been used in such contexts not only to contain solar gains but also to protect against cold winter because of its capacity to store and to slowly release energy. This research investigates how thermal inertia on roof slabs could positively affect the comfort indoors, also in buildings that tend towards being nearly zero-energy buildings, as suggested by last European Directive 2010/31/EU. With this aim, an experiment was conducted on a full-scale building with different roofs, on light and heavy slabs, under hot and moderate climatic conditions (Ancona, Italy). The thermal performance of roofs was monitored during summer and winter seasons. In winter, the building was also subjected to cyclical internal heat gains. The experiment demonstrated that a certain thermal inertia in the slab guarantees better indoor comfort in both summer and winter, and it can also reduce energy consumption from heating. [ABSTRACT FROM PUBLISHER]

Abstract: Environmental pollution is constantly increasing and it causes aesthetical concerns to urban buildings exposed to the atmosphere. Nanometric titanium dioxide (TiO2) has become a promising photocatalytic material owing to its ability to accelerate degradation of many organic contaminants. Application of TiO2 is rising and it found application on building industry. However, photocatalytic properties of this nanotechnology strongly depend on substrate morphology and on its nature. Thus, it is not correct to extrapolate photocatalytic activity on different types of substrate. Moreover, very few information is available about effectiveness of TiO2 coatings after aging phenomena when applied on different substrate. This paper aims to investigate photocatalytic properties of TiO2 applied on clay brick surfaces both after deposition and after aging process. TiO2 characterization was carried out by assessing nano-film morphology, wettability and self-cleaning efficiency before durability test. Self-cleaning ability was also evaluated during aging test in order to evaluate its variation in long term applications. Results show that photocatalytic efficiency of TiO2 remain stable after aging, thus TiO2 shows a good photocatalytic efficiency when it is applied to clay brick substrate. In the long run, photocatalytic efficiency of clay brick specimens treated with TiO2 is seven times higher than untreated specimens. [Copyright &y& Elsevier]

Abstract: Microalgal growth largely affects the aesthetical properties of building façades worldwide. It causes biodeterioration of building materials and, in a later stage, it can compromise integrity of the elements and their durability. Recently, the use of nanotechnology to prevent the growth of microalgae is rising. One of the most widespread and promising material is titanium dioxide (TiO2). Photocatalytic properties of TiO2 inhibit biofouling of microalgae when this coating is stimulated by UV radiation coming from the sun or from artificial light. In this study, the biocide effect of TiO2 coatings applied on clay brick specimens under weak UV radiation was assessed. Results revealed that TiO2 nanocoating was not able to fully prevent microalgal biofouling, but under optimal UV exposure conditions for the growth of microalgae it efficaciously prevented the adhesion of these microorganisms on the treated substrates through the formation of a superficial water film. This property resulted in a good self-cleaning efficiency of TiO2. [Copyright &y& Elsevier]

The use of reflective insulation materials in buildings, for energy saving in summer, has been spreading in southern Europe. These products are not typical of the local building context. There is a lack of well-established measurement systems for reflective insulation thermal transmittance. The aim of this article is to understand whether a reflective insulation material could be effective in hot and temperate climate, also compared with other roof solutions. For this purpose, we compared the thermal performance of a roof with and without reflective insulation, both installed in a full-scale experimental building near Ancona (Italy) in the summer period. The results showed that the reflective insulation benefits are quite limited when using the insulation level imposed by actual laws, which consider insulation as the main strategy for energy saving in temperate and hot climates. [ABSTRACT FROM AUTHOR]

Highlights • Microalgae biofouling on different porous and rough fired brick surfaces was studied. • Its growth under different values of relative humidity and temperature was tested. • At relative humidity lower than 98% no growth was present. • Temperature influenced algae growth rate and covered area as a function of time. • Biofouling experimental results were modelled by a modified Avrami's law. Abstract The purpose of this study was to evaluate the effect of environmental temperature and relative humidity on algae biofouling that often occurs on porous and rough fired brick surfaces. Brick samples were chosen since their common use on building façades. Accelerated growth tests were performed under different relative humidities and different temperatures. Results showed the effects of different temperature conditions in terms of algae growth delay and reduction of the covered area. All the relative humidity conditions tested substantially showed no growth from an engineering standpoint. The modified Avrami's law succeeded in modelling the biofouling under the different environmental conditions. [ABSTRACT FROM AUTHOR]

An interview with Marco D'Orazio, the president of Ar.Tec - Scientific Association for Promoting Connections Between Architecture and Building Technologies, is presented which includes questions on the university research system, and scientific societies.

During the last decades, virtual reality (VR) has been devoted to supporting research in the architecture, engineering, and construction sectors because of its ability to provide multisensory three-dimensional (3D) environments. However, the use of immersive virtual environments (IVEs) in the design of the built environment is still in its infancy, and it is limited to visually designed spaces. In addition, a fundamental challenge lies in improving the sense of hearing. The effective simulation of the built environment with an overall realistic perception will support designers when identifying the influence of design decisions and building acoustics on individuals, therefore, properly designing acoustic strategies. In this study, five disrupting sound sources were selected to create a binaural soundtrack that was integrated within a virtual office environment to evaluate the effectiveness of the model (i.e., ecological validity) and the effects of acoustics on user comfort and cognitive performance (i.e., criterion validity). Independent measure design research was employed. In total, 104 participants performed working memory, inhibition, and task-switching tests under quiet (Q) or noise (N) conditions when the indoor air temperature remained constant. The results showed that the modeled virtual office created an excellent level of presence and immersivity with no significant cybersickness disorders (i.e., ecological validity). Ambient noise disrupted work efficiency with a relevant decrease in performance in each cognitive test (i.e., criterion validity). The sound environment was assessed as uncomfortable, chaotic, and boring. In addition, it negatively impacted the subjects' thermal comfort vote (TCV). These results suggested the adequacy of IVE when providing an accurate representation of the variables measured; therefore, it supported effective user-centered design analysis and strategies. [ABSTRACT FROM AUTHOR]

From the advent of nanotechnologies in building constructions, many materials were functionalized to create composite material with new properties. Titania (TiO 2 ) is actually the most promising nanotechnology to create composite materials with self-cleaning and anti-microbial properties. TiO 2 was able to limit algae adhesion and their growth, even if, in case of high porous and rough substrata, their inhibitory effect seems to be limited. This way, in this study, silver and copper nano-particulate enhanced an aqueous nano-titania solution were applied on brick specimens and their inhibitory effects were tested during accelerated laboratory tests. Extent of biofouling on specimens’ surface was assessed by measuring the aesthetical alteration and correlations between algal growth and key parameters of substrata were discussed. Results confirm the key role of porosity and roughness on the biofouling process on untreated specimens, and their effect on the photocatalytic power of the tested nano-coatings toward algal adhesion. Results from this study were compared with previous findings in the literature on the same types of specimens only treated with the same aqueous nano-titania solution. No significant improvements were detected by the addition of metal nanoparticles. Experimental curves were overlapped to analytical model calculated by Avrami’s law, and its validity was confirmed where latency time could be observed. Whereas no latency time was detected, that is a very fast adhesion of algal cells occurred, the experimental curves were modelled by using a four parametric logistic model that was able to describe numerically the biofouling process. [ABSTRACT FROM AUTHOR]

Fire risk in Architectural Heritage represents a fundamental problem for occupants’ safety. Italian-style historical theatres are one of the most interesting examples because of their historic and artistic value, high fire vulnerability, fire sources and occupants’ features (many people are not familiar with the architectural spaces). Current fire safety regulations approaches for similar Architectural Heritage generally suggest massive and irreversible interventions in order to improve the occupants’ level of safety: main related solutions concern with interventions on building layout (e.g. introduction of fire-proof elements; increasing dimension and number of evacuation paths and exits). This really implies a conflict in preserving original architectural characteristics. Besides, experiments demonstrate how these adopted solutions can be insufficient in improving the individuals’ safety level, especially in case of high occupants’ density and people who are unfamiliar with the building itself, because of individuals’ behaviours in emergency conditions. An efficient emergency evacuation layout has to be able to help evacuating occupants, especially in smoke or blackout conditions. “Intelligent Evacuation Guidance Systems” (IEGS) could monitor human behaviours (how people move) and related criticisms in the evacuation process (e.g. slowing down along paths, paths blockage). Then, they could elaborate these data through smart inducing algorithm so as to suggest dynamic evacuation paths to occupants. In this way, IEGS can effectively suggest the “best” evacuation path to occupants depending on the effective human behaviours. In this paper, an IEGS is firstly defined by introducing suggested low impact environmental components and their related requirements. In particular, occupants’ behaviours are associated to evacuees’ density along egress paths, doors and exits, by using indoor individuals’ tracking systems (e.g. RFID, Wireless localization). A density-based algorithm based on Level-of-Service conditions is adopted for evaluating possible overcrowding phenomena and identify the best evacuation paths. Directional electrically-illumined signs are used so as to indicate the proper direction to occupants. Wireless communication between the system elements is required. Each element is provided with backup power supply. Then, the proposed IEGS is evaluated by applying it to a significant case study (the “Gentile da Fabriano theatre” in Fabriano, AN). Interactions between occupants and IEGS are reproduced within a validated fire evacuation simulator (FDS + EVAC), and the system effectiveness is evaluated by performing evacuation simulation for the whole building. Comparisons of evacuation times between the original scenario and the IEGS-related one are proposed. Total maximum egress time is reduced down to 26% in the IEGS scenario (40% for levels with 3 or more different possible paths). The number of people using secondary paths (that are also the less crowded ones) raises to 88%. IEGS elements correctly and fully interact with people by understanding their evacuation behaviour and suggesting them the most appropriate (clearest) path: hence, the overall evacuation efficiency can be so increased by virtue of this “behavioural design” approach. Besides, it is strongly important to underline how IEGS elements provide no architectural modifications. [ABSTRACT FROM AUTHOR]

Biofouling on building façades, caused by the growth of bacteria, algae, cyanobacteria, fungi, lichens and plants leads to aesthetical degradation and to an increase in the maintenance costs consequently. Recently, the use of nanotechnology to prevent this phenomenon has been increased due to their efficiency and affordable cost. Currently, the research focuses on the numerical modelling of biofouling in order to simulate the biofouling processes and to find the correlations between physical properties of substrata and growth of microorganisms. In this paper, biofouling tests were conducted on fired brick substrata with different intrinsic characteristics (porosity and roughness) by means of an accelerated growth test. Biofouling was evaluated through time by digital image analysis of specimens׳ surface and then the Avrami׳s law was applied to modelize the biofouling process. The model was adapted to include the inhibitory effect of TiO 2 and a modified equation of Avrami was proposed. Results show a good agreement between simulation and the experimental data. Furthermore, the assumptions taken into account to discretize the real phenomenon were acceptable. The experimental analysis and the numerical modelling showed how the roughness and the porosity influenced the algal attachment. [ABSTRACT FROM AUTHOR]

Earthquake risk assessment at urban scale is actually based on site hazard, buildings vulnerability and exposition, but does not consider human behaviours during both the event and the evacuation. Nevertheless, human interactions in such conditions become one of the most influencing element for inhabitants safety. Hence, an important issue is understanding how people interact with other individuals and with the environment modified by the earthquake. The development of evacuation software in earthquake conditions needs investigations about these aspects. In fact, actual data about earthquake evacuation behaviours are very poor. This work starts from this request and proposes an innovative database for earthquake evacuation models according to literature suggestions. A wide number of videotapes concerning real events from all over the World is analysed in order to provide human behaviours and motion quantities, and to integrate previous results. The database firstly includes the step-by-step evacuation behaviours that are activated during the process. Secondly, motion quantities (speed, acceleration, and distance from obstacles) are provided. The analysis of real emergency conditions evidences particular phenomena. Main results demonstrate how people prefer moving with an average speed of about 2.3–3 m/s. Finally, fundamental diagrams of pedestrians’ dynamics in earthquake emergency conditions show how, density values being equals, speeds and flows are higher than previous studies (in particular: fire evacuation and evacuation drill). These data can be used as input parameters for defining and developing new evacuation models, but also for existent models validation. [ABSTRACT FROM AUTHOR]

The human-nature connection is one of the main aspects determining supportive and comfortable office environments. In this context, the application of eye-tracking-equipped Virtual Reality (VR) devices to support an evaluation on the effect of greenery elements indoors on individuals' efficiency and engagement is limited. A new approach to investigate visual attention, distraction, cognitive load and performance in this field is carried out via a pilot-study comparing three virtual office layouts (Indoor Green, Outdoor Green and Non-Biophilic). 63 participants completed cognitive tasks and surveys while measuring gaze behaviour. Sense of presence, immersivity and cybersickness results supported the ecological validity of VR. Visual attention was positively influenced by the proximity of users to the greenery element, while visual distraction from tasks was negatively influenced by the dimension of the greenery. In the presence of greenery elements, lower cognitive loads and more efficient information searching, resulting in improved performance, were also highlighted. [ABSTRACT FROM AUTHOR]

• Human stability during floods was investigated. • Experimental tests on a physical model were carried out. • Different combinations of water depth and flow speed were considered. • Empirical laws governing the stability conditions were found. Urban floods are becoming more and more intense and frequent allover the world. Extreme events are the main triggering factors of such floods, and merit attention for what concerns the urban planning and emergency strategies. Numerical models aimed at investigating the optimal paths for evacuees escaping a flooded urban environment may be used by local authorities to properly understand how to improve people safety and mitigate the flood risk. Implementation of empirical laws in such models to describe the people stability in flooded areas is thus crucial to understand the behavior of evacuees and rescuers during emergency conditions. Laboratory experiments have been undertaken using a physical model representing a human body at quasi-natural scale, towed by an electrical engine in the water at rest. This represents a novel laboratory approach which exploits a non-inertial reference frame in motion with the model. The experimental results, obtained using different combinations of water depth and flow speed, have led to empirical laws which outline the stability conditions occurring when either the model front or the model back faces the flow, these respectively corresponding to Backward Toppling Instability (BTI) and Forward Toppling Instability (FTI). Such laws have been found through comparison with reference literature works, using various statistical methods. The FTI condition has been seen to largely improve the human stability compared to BTI, in contrast to the results of previous literature works, which stated an overall similarity between the results of the two toppling conditions. To better understand the role of the water flow during the different tests, hydraulic forces and moments have been measured. It has been seen that dynamic and static effects are comparable during high-speed conditions, especially due to a relevant fluid-model interaction and an increase of the water-surface level, while dynamic effects are negligible during low-speed conditions. The results of the present contribution can represent an important step forward for the numerical models applied to the framework of urban and emergency planning. [ABSTRACT FROM AUTHOR]

Policies and financial framework aiming to encourage energy efficient building renovations should contribute to "fill" the existing investment gap between Cost-Optimal (CO) solutions, that are more economically convenient, and nearly Zero Energy (nZE) solutions, which have the lower energy consumption, in order to make more convenient to the investors to choose the more energy efficient options. This investment gap depends on the long-term expected value and volatility of several interdependent macroeconomic variables. However, standardized LCC methods used for CO assessments disregard the long-term uncertainty and interdependence affecting these variables and, consequently, misrepresent the impact of the associated risk on the economic convenience. The present work aims to model alternative macro-economic scenarios where to carry out a "stochastic" LCC of predetermined building renovation solutions, in order to provide a useful and effective decision tool for building LCC, and especially to evaluate whether and how much the future macro-economic scenario could influence the investment gap between a CO and a nZE refurbishment solution. At this aim, we estimated the Vector AutoRegressive (VAR) models of four alternative macro-economic scenarios, ranging from a "regular growth" case to more extreme conditions as experienced by major western economies in the last decades, based on real data, i.e. observed time series. The scenarios modelling and its relation to the stochastic LCC is the main result and novelty of the work compared to the conventional approach adopted in most of the literature and suggested by international regulations and standards. The method is illustrated through a case study, which demonstrates the potential of the developed methodology in providing interesting and informative results on the nature of the investment gap between CO and nZE solutions, that the policy should contribute to fill in order to address the environmental challenge in the building sector, and on how much this gap may vary depending on the volatility of the macro-economic context. The novelty of the work mainly lies on the possibility to highlight in which specific macroeconomic conditions the convenience of taking an investment decision under risk-aversion may be jeopardised (augmented), thus requiring a stronger (weaker) compensating public support. • Macroeconomic scenarios are included in a stochastic LCC of building retrofit. • These scenarios are modelled with Vector AutoRegression based on real time series. • This novel stochastic LCC provides decision support in the building sector. • It investigates the investment gap across solutions under alternative scenarios. • It can be used to assess the investment gap of nZEB and develop proper policies. [ABSTRACT FROM AUTHOR]

• Human motion in flood evacuation is analysed in different floodwater depths. • Laboratory experiments with volunteers are performed to relate floodwaters features and motion speed. • Both "walking" and "running" conditions are tested. • The influence of individuals' characteristics (age, height, mass, BMI) on evacuation motion are considered. • Results are compared to previous works and relations are proposed for evacuation simulations. Studies on flood risk assessment at urban scale are becoming increasingly oriented towards the use of evacuation simulation models for population's safety. However, such tools generally simplify human dynamics in floodwater conditions and need data to quantify proper individual's speed. Novel information on the above dynamics is here presented. A group of over 200 volunteers has been engaged in evacuation laboratory experiments carried out into an open channel. Results allow to estimate the pedestrian's isolated motion speed as a function of depth D [m] (in the range 20–70 cm) of floodwater, in both "walking" and "running" conditions. To this aim, experiments were carried out in still water. For each walking conditions and floodwater depth, correlations have been obtained between evacuation speed and age, individuals' height, mass and body mass index. The existence of significant motion speed differences, depending on D , is underlined. In addition, general trends in evacuation speed reduction depending on the specific flood force per unit width M have been investigated and confirmed. It is also clarified how human physiology and kinematics (i.e. knee articulation) can induce specific speed-affecting effects depending on D. Such quantitative differences in motion discourage the use of fire or general-purpose databases for flood simulations, while such experimental data could be used as input for evacuation models to describe different evacuees' walking types in evacuation procedure. [ABSTRACT FROM AUTHOR]

TiO 2 -based nanocoatings have been becoming more and more widespread during last years in Cultural Heritage: they seem to be able to keep stone surfaces self-cleaned and to prevent the formation of biofouling. However, the efficiency of these coatings is strongly dependent on the substrate (i.e.: porosity and roughness) and on the amount of TiO 2 . Thus, this study experimentally investigates on the self-cleaning and anti-biofouling efficiency of a nano-TiO 2 dispersion (without any organic or inorganic additive) applied on six different types of natural stones (three limestones, two sandstones and one tuff) usually used in Cultural Heritage, where high porosity and roughness can be found and the TiO 2 amount cannot be increased in order to avoid any chromatic variation of the substrate. Water was used as solvent so as to reduce the risk of exposition of hazardous materials and to eliminate any chemical action on stones. The self-cleaning power of the coating was evaluated by measuring its ability at discolouring organic dye Methylene Blue, while its anti-biofouling efficiency was assessed by an accelerated growth test under controlled climatic conditions of two algal microorganisms, namely Chlorella mirabilis and Chroococcidiopsis fissurarum . Results show that, even if the photocatalytic and biocide power of nano-TiO 2 itself is well known in literature, its application for the maintenance of stones in Cultural Heritage does not seem to be an effective strategy, especially when stones are highly porous and rough. Roughness and porosity of stones, in fact, can limit the efficiency of TiO 2 , which is thus not able to powerfully keep the stone substrate cleaned or slow down algal proliferation. [ABSTRACT FROM AUTHOR]

Flood risk assessment in urban regions does not account for human behaviours during emergency. Understanding behaviours during floods and developing related simulators highlight critical phenomena for individuals' safety, during and after the flood, and suggest risk-reduction strategies aimed at helping evacuees. The proposed Flooding Pedestrians' Evacuation Dynamics Simulator (FlooPEDS) combines flood hydrodynamics (based on Nonlinear Shallow Water Equations) and individuals' evacuation (by modifying the Social Force Model). FlooPEDS capabilities are illustrated with reference to an important case study. Results focus on evacuees’ motion and path choices. This preliminary simulator implementation, still raw for practical use by planners and authorities, is already mature to guide the design of innovative resilience-increasing urban solutions (i.e.: architectural components like handrails, raised flooring systems) in specific hazardous urban areas, as support to traditional strategies (i.e.: early warning systems; evacuation plan communication). [ABSTRACT FROM AUTHOR]

In earthquake disasters, the leading causes of death are directly related both to build collapses and fatalities during the following evacuation phase. Allowing people to autonomously gain safe areas and assembly points should be the basis for reducing human losses in urban systems. However, some important environmental and behavioural factors (e.g. vulnerability of buildings, compact urban fabric, cascade effects, presence of people unfamiliar with the urban layout, absence of information on evacuation paths) can hinder this ‘self-help’-based evacuation process. This issue is really important in historical centres where evacuees suffer a combination of unfavourable conditions to safely escape. This paper concerns a non-invasive solution for guiding people along probable safe evacuation routes in earthquake emergency. The proposed Seismic Pedestrians' Evacuation Dynamic Guidance Expert System ( SpeedGuides ) considers the influence of the main environmental and behavioural safety factors for evacuees (i.e. street vulnerability, street blockages probability, crowding conditions along paths, presence of mortal dangers, visibility conditions) and combines them in a safety index through the Multi-criteria techniques application. SpeedGuides dynamically collects safety factor data during the time and suggests the possible safest path to the nearest secure zone according to the Dijkstra's algorithm approach. SpeedGuides is an easy-to-use model proposed for application on personal devices (e.g. smartphone) that, taking advantage of different expert methods, allows evacuees to simple enhance their safety. A first effectiveness evaluation of SpeedGuides is provided through an earthquake pedestrians' evacuation simulator in a significant case study. The evacuee performances (with and without the proposed guidance tool) are compared and discussed. Results demonstrate how individuals' safety levels are increased when evacuees use SpeedGuides . [ABSTRACT FROM AUTHOR]

Public Open Spaces (POSs) such as streets and squares, in our cities are characterized by spatio-temporal variations of users' vulnerability and exposure in view of the hosted social, governmental, religious, and commercial functions. Single or multi-risks conditions in POSs can hence vary over time. This work proposes a methodology to perform local-scale analyses on use patterns in real-world POSs, pursuing a quick-to-apply approach based on remote analysis tools and easy-to-apply surveys, to be also used by non-expert technicians. Main literature-based factors concerning users' vulnerability/exposure and methods for their collection are identified. Rules to define typological (that is recurring) scenarios are provided through specific key performance indicators relating to overall POS use and daily/hourly temporalities. The methodology capabilities are preliminary assessed through a sample of 56 squares in historic Italian cities, considering working days and holidays. Results trace the overall typological characterization of the squares sample adopting a "robust-to-outliers" approach, and provide bases for expeditious assessment of users' vulnerability and exposure scenarios. The typological scenarios can be then used to support rapid risk assessment actions in POSs by safety designers and local authority technicians, and employed as input in simulation-based analyses to include the users' features in the related evaluations. • A method to quickly assess patterns in users' vulnerability and exposure in public outdoor spaces (POSs) is proposed. • Users number and typologies over space and time are derived by intended uses and temporalities of POSs and facing buildings. • Key performance indicators characterize such POSs features in a general, daily and hourly manner. • The method is applied to a sample of historical squares of the Italian context as significant POSs. • Results offer typological POSs scenarios on users' vulnerability and exposure for working days and holidays. [ABSTRACT FROM AUTHOR]