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This paper presents an overview of the ROSSINI project, illustrating its general objectives and how it places itself within the overall field of seismic risk-aware navigation systems. In particular, it describes the use of a sensor array for the integrated risk-aware navigation in industrial plants at risk of NaTech accidents. The integration of structural and environmental risks estimated and measured in different ways is presented as part of an integrated risk identification and evaluation (RIE) module. This module will be used along with a series of logic to combine and map the possible risks spatially within an industrial plant’s layout. It is seen how this information can then be used to not only compute the safest path to safety for a worker located within such a plant but also how mobile communications can be used to aid and guide them in different scenarios. All of this stems from the use of a sensor array network in a relatively novel way within this particular context. The paper discusses the progress to date and presents the ongoing results of a pilot case study application of the system to an industrial plant facility in Italy.

In this paper, empirical fragility curves for reinforced concrete buildings are derived, based on post-earthquake damage data collected in the aftermath of earthquakes occurred in Italy in the period 1976–2012. These data, made available through an online platform called Da.D.O., provide information on building position, building characteristics and damage detected on different structural components. A critical review of this huge amount of data is carried out to guarantee the consistency among all the considered databases. Then, an in-depth analysis of the degree of completeness of the survey campaign is made, aiming at the identification of the Municipalities subjected to a partial survey campaign, which are discarded from fragility analysis. At the end of this stage, only the Irpinia 1980 and L’Aquila 2009 databases are considered for further elaborations, as fully complying with these criteria. The resulting database is then integrated with non-inspected buildings sited in less affected areas (assumed undamaged), to account for the negative evidence of damage. The PGA evaluated from the shakemaps of the Italian National Institute of Geophysics and Volcanology (INGV) and a metric based on six damage levels according to EMS-98 are used for fragility analysis. The damage levels are obtained from observed damage collected during post-earthquake inspections through existing conversion rules, considering damage to vertical structures and infills/partitions. The maximum damage level observed on vertical structures and infills/partitions is then associated to the whole building. Fragility curves for two vulnerability classes, C2 and D, further subdivided into three classes of building height, are obtained from those derived for specific structural typologies (identified based on building height and type of design), using their frequency of occurrence at national level as weights.

This paper illustrates the derivation of an empirical fragility model for residential unreinforced masonry (URM) buildings, calibrated on Italian post-earthquake damage data and compatible with the key features of the Italian national seismic risk platform. Seismic vulnerability is described by fragility functions for three vulnerability classes, then refined based on the building height. To this aim, a clustering strategy is implemented to merge predefined building typologies into vulnerability classes, based on the similarity of the observed seismic fragility. On the other side, a specific procedure is built up to determine the vulnerability composition of the exposed URM building stock, starting from national census data. The empirically-derived model was implemented into the national seismic risk platform and used, together with other vulnerability models, for assessing seismic risk in Italy. The results presented in this paper, consisting of refined typological fragility curves and fragility curves for vulnerability classes, can be also exploited for estimating both expected seismic damage and risk in sites with similar seismic hazard and building inventory.

This paper explores and validates the use of ground shaking scenarios generated via 3D physics-based numerical simulations (PBS) for seismic fragility studies. The 2009 L’Aquila seismic event is selected as case-study application, given the availability of a robust and exhaustive post-earthquake database, gathering observed seismic damages detected on several building typologies representative of the Italian built environment, and of a validated numerical model for PBS ground shaking scenarios. Empirical fragility curves are derived as a function of different seismic intensity measures, by taking advantage of an improved statistical technique, overcoming possible uncertainties in the resulting estimates entailed by data aggregation. PBS-based fragility functions are compared to the corresponding sets of curves relying on updated ShakeMaps. The predictive capability of the adopted simulation strategies is then verified in terms of seismic damage scenarios, by respectively coupling PBS- and ShakeMap-based fragility models with the corresponding ground shaking scenarios. Comparison of observed and predicted damage distributions highlights the suitability of PBS for region-specific seismic vulnerability and risk applications.

Industrial plants are quite susceptible to NaTech disasters during earthquakes caused by damage to structural and non-structural components and the potential release of toxic materials. To mitigate and manage this risk, the ROSSINI project was initiated and its results are described here for what concerns industrial plant worker safety and their risk-based navigation in emergency situations. The project includes a data acquisition system consisting of a data acquisition board and an array of different sensor technologies, which process the seismic event and other meteorological information before passing them as inputs towards the risk identification and evaluation (RIE) modules. Here, the risks associated with structural and non-structural damage and health risks associated with the release of harmful substances are estimated and combined to form a navigable risk map. This map is used within a purpose-built risk-based navigation application for the safe egress of workers from an industrial plant. To demonstrate the implementation of this system, two case-study industrial plant layouts consisting of buildings, non-structural components, liquid storage tanks, piping systems, and chemical storage vessels, were devised. This paper describes the project’s implementation in these contexts and illustrates the results via several example scenarios.

The Department of Civil Protection (DPC), in compliance with the EU decision 1313/2013 and at the request of the Sendai Framework for Disaster Risk Reduction 2015–2030 to update the disaster risk assessments by various countries, released the latest National Risk Assessment for Italy at the end of 2018. Specifically, as regards the seismic risk assessment, six research units belonging to two centres of competence of the DPC collaborated under its guidance to update the risk maps of the Italian residential heritage. This extensive collaboration complied with the recent Italian code for Civil Protection, which requires a broad scientific consensus for risk assessment. During this research activity, six fragility models were developed, according to some common criteria (four for masonry buildings and two for RC buildings). These models were then implemented by the DPC for the definition of the national seismic risk. Within this context, the aim of this paper is to evaluate the risk results provided by these models, compare their features, and assess and validate their prediction capabilities. In particular, this paper shows the comparison of predicted and observed damage scenarios and consequences on building stock and the population of two seismic events, i.e. L’Aquila 2009 and Amatrice 2016. Furthermore, the paper provides some interesting damage and risk predictions at a national level. Overall, the forecasts and comparisons made in this study demonstrate the validity of the approach adopted by the DPC for the assessment of national seismic risk.

Post-earthquake damage data represent an invaluable source of information for the seismic vulnerability assessment of the exposed building stock, as they are a direct evidence of the actual buildings’ performance under real seismic events. This paper exploits a robust and homogeneous database of damage data collected after the 2009 L’Aquila (Italy) earthquake, to derive damage probability matrices for several building typologies representative of the Italian building stock. To this aim, the first part of the work investigates several issues related to the definition of damage to be associated with each inspected building. Different approaches and damage conversion rules are applied, pointing out advantages and weaknesses of each one. Considering the widespread seismic damage observed on masonry infill panels and partitions of reinforced concrete constructions, the impact of this type of non-structural damage on empirical damage and functional loss distributions is explored. The second part of the study proposes different possible interpretations of the repartition of the observed damage in the different damage levels, showing in some cases a bimodal trend. Two novel hybrid procedures are outlined and compared with the classical binomial approach for predicting the subdivision of damage in the different levels. The application of the proposed methodologies to the different building typologies allows the selection, for each one, of the method providing the best fit to empirical results. The parameters required for the application of the optimal approach are reported in the paper, so that results can be used for forecasting the expected seismic damage in sites with similar seismic hazard and exposed buildings.

The companion paper by Rota and Rosti (Bull Earthq Eng, 2017) illustrates a methodology for comparing PSH results with historical macroseismic observations at different scales, in terms of mean damage. This paper presents examples of application of the methodology, at the different considered scales, to the South-East quarter of France. This moderate seismicity region is characterised by a long history of civilization, which makes macroseismic observations available for a long time span, although they are highly approximated measures of the seismic action and they are affected by significant uncertainties. The first scale of application presented is at a single site, i.e. the city of Annecy. This example shows that, despite the seismic history of this city is characterised by a significant number of macroseismic observations spanning over a long time period, they mostly consist of very low intensity values and hence the comparison at a single site is not very meaningful. Therefore, the comparison is carried out on a set of seven aggregated sites, well distributed in the region of interest, providing interesting results and suggesting the opportunity of extending the comparison at an even larger scale. The comparison at the regional scale also allows some interesting observations, although it is obviously able to only provide general (average) indications on the PSH results. These comparisons were aimed at showing the applicability of the proposed methodology, pointing out advantages and drawbacks of the different application scales.

The need for verifying and/or validating the results of probabilistic seismic hazard studies has become evident, despite the absence of generally accepted methods for judging such results. This paper proposes a methodology for comparing the results of PSH with historical macroseismic observations, at different scale levels. The selected metric of the comparison is the mean damage, i.e. the average annually expected damage. Hence, a procedure for converting macroseismic observations and PGA levels, for which PSH estimates are provided, into mean damage values is first presented. The procedure is based on the macroseismic method for converting intensities into mean damage values, whereas it takes advantage of fragility curves (representative of the seismic vulnerability of the building stock at the time of historical observations) to transform the rates of occurrence of PGA values into the equivalent quantity in terms of mean damage. A methodology for site-specific comparison is first outlined. To overcome some of the limitations of the comparison at a single site, two procedures for aggregating several sites by sampling in space are then presented, with the aim of enlarging the available macroseismic dataset. Finally, a procedure for the comparison at the regional level is discussed. Applications of the proposed methodologies will be discussed in a companion paper (Rosti and Rota in Bull Earthq Eng, 2017).

La valutazione del rischio sismico a scala territoriale è fondamentale per la gestione dell’emergenza post-terremoto, quantificazione delle perdite socio-economiche dovute a terremoti futuri, definizione di strategie di mitigazione del rischio, ottimizzazione di piani di intervento. Affinché le conseguenze dovute a futuri eventi sismici possano essere efficacemente mitigate, è necessario disporre di stime di rischio accurate e affidabili. In questo contesto, la difficoltà principale è legata alla definizione del rischio stesso, che, risultando dalla convoluzione di pericolosità, esposizione e vulnerabilità, richiede il coinvolgimento di diverse discipline scientifiche. In questo lavoro, modelli di vulnerabilità per edifici residenziali in muratura e c.a., derivati empiricamente sulla base di dati di danno post-terremoto, sono implementati nella piattaforma nazionale del rischio sismico, al fine di produrre stime di rischio a scala territoriale. Diversi sono i casi studio presentati, focalizzati sulla valutazione del rischio incondizionato. I risultati sono mostrati per diversi tipi di conseguenze, quali vittime, perdite economiche, impatto in termini di abitazioni inagibili e crollate e numero di sfollati.

Questo lavoro presenta curve di fragilità empiriche per il costruito esistente in c.a., da utilizzare per la valutazione del rischio sismico a scala territoriale. Le curve sono state derivate elaborando statisticamente i dati di danno postterremoto raccolti nella piattaforma Da.D.O., utilizzando l’accelerazione di picco al suolo (PGA) stimata da shakemap come misura di intensità per la caratterizzazione dello scuotimento. Gli edifici in c.a. sono classificati in quindici tipologie edilizie, identificate sulla base del numero di piani (da 1 a 5 piani) e tipo di progettazione (edifici progettati per soli carichi gravitazionali, per carichi sismici pre-1981 e post-1981). In primo luogo, le curve di fragilità sono state derivate per le tipologie edilizie identificate e per cinque livelli di danno della EMS-98, tenendo conto del danno osservato su componenti strutturali e non strutturali. Successivamente, si sono derivate curve di fragilità per due classi di vulnerabilità a vulnerabilità decrescente e tre classi di piano, pesando le curve di fragilità tipologiche sulla base della composizione del costruito esistente.

An experimental campaign aiming at investigating the seismic performance of unreinforced masonry low-density autoclaved aerated concrete blocks is presented. After characterization tests on blocks, mortar and wallettes, in-plane cyclic tests on six full-scale unreinforced masonry piers were performed to obtain a reliable description of the lateral cyclic behavior. Information regarding the displacement capacity and the correlation between experimental and analytical strengths were derived. The results show a limited in-plane displacement capacity of piers, strongly depending on the applied vertical load, and a good correlation between experimental and calculated lateral strengths. At the end of the cyclic tests, the residual vertical strength of some walls was also directly checked.

Masonry walls constructed with lightweight AAC blocks and thin-layer mortar meet the increasingly strict requirements of energy efficiency and sustainability. In this sense, they represent an excellent solution for modern buildings, not only for external cladding but also as loadbearing elements. Despite the possible advantages of using lightweight AAC masonry, a specific assessment of its seismic performance is mandatory in order to set design recommendations allowing to reach safety levels consistent with those required for other masonry types complying with EN 1998 standard requirements. A comprehensive study on the seismic performance of unreinforced masonry buildings made of lightweight AAC was carried out in an integrated experimental-numerical approach. The experimental campaign provided the necessary information to setup a reliable numerical model to be extensively used to assess the seismic performance of a number of prototype AAC masonry buildings with different characteristics, by means of both linear and nonlinear static (pushover) analysis. The results of this systematic numerical assessment were eventually used to draft design recommendations, to set parameters (behaviour factors) to be used in linear analysis and to calibrate rules for simple buildings. Mauerwerkswande aus Porenbetonblocken und Dunnbettmortel erfullen die zunehmend strengeren Anforderungen an Energieeffizienz und Nachhaltigkeit. Sie stellen in dieser Hinsicht eine exzellente Losung fur moderne Gebaude dar, nicht nur fur die Ausenverkleidung, sondern auch als tragende Bauteile. Trotz der Vorteile, die der Einsatz von Porenbetonmauerwerk bietet, ist eine spezifische Bewertung seines seismischen Verhaltens erforderlich, um Bemessungsempfehlungen festlegen zu konnen, die die Anforderungen der Norm EN 1998 erfullen. Unter Anwendung eines kombinierten experimentellen und numerischen Ansatzes wurde eine umfassende Studie des seismischen Verhaltens von unbewehrten Mauerwerksgebauden aus Porenbeton durchgefuhrt. Die Versuchsreihe lieferte die notwendigen Informationen fur die Entwicklung eines zuverlassigen Modells, das breit eingesetzt werden kann, um das Erdbebenverhalten einer Reihe von prototypischen Mauerwerksbauten aus Porenbeton mit unterschiedlichen Charakteristika sowohl durch lineare als auch nichtlineare statische (Pushover-) Analysen zu bewerten. Die Ergebnisse dieser systematischen numerischen Bewertung wurden schlieslich dazu verwendet, Bemessungsempfehlungen zu formulieren, Parameter (Verhaltensfaktoren) zur Verwendung in linearen Analysen festzulegen und Regeln fur einfache Gebaude aufzustellen.

A suitable characterisation of seismic input at the sites where damage is reported is a key aspect of the study of empirical seismic fragility. The availability of a shakemap, specifically derived for the event of interest from recorded ground motions, allows considering site conditions, spatial variability and possible directivity effects. Whenever this is not available, alternative solutions must be considered, such as for example the use of ground motion prediction equations (GMPEs) or the generation of conditional spatially correlated ground motion random fields (CSCRFs). Each of these approaches bears several uncertainties, which obviously have an effect on the derived empirical damage probability matrices. This paper explores issues and procedures related with the ground motion characterisation and assesses their impact on empirical damage distributions derived from a comprehensive post-earthquake damage database, compiled after the 2009 L'Aquila (Italy) seismic event. Several GMPEs are qualitatively and quantitatively ranked with respect to the available accelerometric data and the damage probability matrices obtained with the best performing GMPE are then compared with results obtained using more refined ground motion characterisations.