Seismic Risk In Italy Research Articles

SICURO+: A web platform to raise awareness on seismic risk in Italy

Italy is a country with high seismic risk. In the past many catastrophic earthquakes have occurred causing severe damage to buildings and infrastructures, serious economic impacts, and the loss of thousands of human lives. To mitigate the impact of seismic risk, as well as of other risks, many efforts have been made, implementing preventive structural measures and acting to raise awareness in the community. In Italy, this need was strengthened with the emanation of the new Civil Protection Code (D.Lgs January 2, 2018 n.1), with the purpose of encouraging the participation of citizens and spreading risk knowledge and the culture of civil protection, thus contributing to “increase the resilience of communities” (art. 31). As part of the agreement between the Italian Civil Protection Department (ICPD) and EUCENTRE (European Centre for training and research in Earthquake Engineering), an interactive web-tool was developed to allow citizens to display the most updated seismic risk maps. These maps were produced in 2018 by the ICPD, with the relevant support of the scientific community operating in the field of seismic risk, in particular of ReLUIS (The Laboratories University Network of seismic engineering) and EUCENTRE. The web-tool, named SICURO+ (Information System for Risk Communication, www.sicuropiu.it), was created to raise awareness in citizens on seismic risk in the place where they live, work, or go on holiday. Communication strategies and behavioural techniques were designed and tested experimentally with the support of behavioural scientists, as part of an agreement between the National School of Administration and the Prime Minister's Office.

Seismic vulnerability of gravity load design r.c. buildings of 1960s in low seismic areas

In recent years, there has been a substantial increase in the issues of assessing the seismic vulnerability of existing structures and reducing seismic risk in Italy. Most of the buildings in Italy dates back to 1950s-60s and are Reinforced Concrete buildings designed only to vertical loads (GLD). In some cases, these buildings are located in areas that were defined as non-seismic zones in previous seismic classification of the national territory. Nowadays, in a whole seismic country the study of the seismic vulnerability of this type of buildings represents a really interesting issue.In this paper the seismic vulnerability of a building of the Olympic Village of Luigi Moretti in Rome has been evaluated, as representative case, originally designed to counteract only vertical loads. This valuable solution by Moretti respects the “five points of modern architecture” by Le Corbusier. It was built on the occasion of the XVII Olympics in 1960 with the aim of hosting the participating athletes. It is characterized by resisting frames only in transverse direction, as occurred for Le Unitè d'Habitation by Le Corbusier.

Application of the SP-BELA methodology to RC residential buildings in Italy to produce seismic risk maps for the national risk assessment

This article deals with the application of an analytical methodology for the large-scale vulnerability assessment of reinforced concrete frame buildings in Italy. This methodology is known in the technical literature with the acronym SP-BELA (Simplified Pushover-Based Earthquake Loss Assessment) and has been adopted by the Eucentre research group to contribute to the production of the seismic risk maps in Italy, published in the National Risk Assessment document. The Italian maps were elaborated using the IRMA platform (Italian Risk MAps), which is a web platform developed by Eucentre. The IRMA platform is only addressed to the scientific community who can use it to share data, methods, and models for the evaluation of the seismic risk in Italy (Borzi et al. in Piattaforma IRMA Italian Risk MAps, 2018; Dolce et al. in Mappe di rischio per il territorio Italiano, 2019a; Faravelli et al. in Italian platform for seismic risk and damage scenario evaluation, 2019a, Borzi et al. in Bull Earthq Eng, 2020, Dolce et al. Bull Earthq Eng, 2020). SP-BELA defines the non-linear behaviour of a random population of buildings through a simplified pushover and a displacement-based procedure. Specifically, displacement capacity limits are identified on the pushover curve and then they are compared with the displacement demand from a response spectrum of each building in the random population. In this way, it is possible to define the probability of exceedance of the damage limits and hence generate the fragility curves. Then, the resulting curves have been calibrated by comparing the damage data observed on the reinforced concrete buildings with the damage analytically calculated with SP-BELA for the earthquakes of Molise 2002 and L’Aquila 2009. The final curves have been uploaded into the IRMA platform and used to produce damage maps for the entire national territory.

Empirical fragility curves for Italian URM buildings

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.

BEST STRATEGY FOR THE DEVELOPMENT OF A SEISMIC PREVENTION PLAN

An effective mitigation of seismic risk in Italy can hardly be obtained without a tentative recognition of few priority zones, where the limited resources available in the short term can be concentrated. A reliable recognition of the zones where the probability of major earthquakes is highest must be carried out by a deterministic approach, exploiting the profound knowledge acquired about the present seismotectonic context in the zones involved. Some years ago, this kind of procedure led us to identify the central-northern Apennines (i.e. the zone hit by the recent major earthquakes, 2016 and 2017) as the Italian area most prone to next strong shocks. The reliability of the methodology here proposed is also supported by the fact that the implications of the adopted tectonic setting can provide plausible and coherent explanations for the spatio-temporal distribution of major earthquakes in the central Mediterranean area in the last six centuries.

Seismic Response of a Strategic Building in Catania (Italy) by 2-D FEM Analysis

In the last 900 years, the east coast of Sicily has been struck by several disastrous earthquakes. The earthquakes occurred in 1169, 1542, 1693, 1818, 1908 and more recently in 1990, with estimated magnitudes, ranging from less than 5.0 to greater than 7.0, testify the high level of hazard in this area. Many towns were destroyed during the above-mentioned earthquakes. The high level of seismicity that affects the area, together with the considerable high density of inhabitants living in its urban area, contribute to classify it as one of the area having the highest seismic risk in Italy. It is also not negligible the high potential damage to which its historic-architectural patrimony could undergo even at moderate magnitudes. Many researches show that the site seismic response is strongly influenced by stratigraphic and topographic features. Site response can reduce or amplify the earthquake induced ground motion. In this study seismic response of strategic building located in Catania has been done, and main results are presented.

Turning the rumor of the May 11, 2011, earthquake prediction in Rome, Italy, into an information day on earthquake hazard

A devastating earthquake was predicted to hit Rome on May 11, 2011. This prediction was never officially released, but it grew on the internet and was amplified by the media. It was erroneously ascribed to Raffaele Bendandi, an Italian self-taught natural scientist who studied planetary motions and related them to earthquakes. Indeed, around May 11, 2011, there was a planetary alignment, and this fed the credibility of the earthquake prediction. During the months preceding May 2011, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) was overwhelmed with requests for information about this prediction, by the inhabitants of Rome and by tourists. Given the echo of this earthquake prediction, on May 11, 2011, the INGV decided to organize an Open Day at its headquarters in Rome, to inform the public about Italian seismicity and earthquake physics. The Open Day was preceded by a press conference two days before, to talk with journalists about this prediction, and to present the Open Day. During this ‘Day’, 13 new videos were also posted on our YouTube/INGVterremoti channel to explain earthquake processes and hazards, and to provide periodic updates on seismicity in Italy from the seismicity monitoring room. On May 11, 2011, the INGV headquarters was peacefully invaded by over 3,000 visitors, from 10:00 am to 9:00 pm: families, students with and without teachers, civil protection groups, and many journalists. This initiative that was built up in a few weeks has had very large feedback, and was a great opportunity to talk with journalists and people about earthquake prediction, and more in general about the seismic risk in Italy.

The Seismic Risk Of The Lifeline In SmallCommunes: The Cross-correlation Effects

A significant part of the consequences of a severe earthquake in an urban area is related to the failure of the lifeline system. A systematic assessment of seismic risk, vulnerability, and criticality of lifelines in small communities (considering them both separately and from a systemic point of view) is performed. The risk is characterized by using functions related to the components of different lifelines. The approach allows the optimization of the use of economic limited resources in intervention to reduce risk. Given a set of remedial measures more expensive than the limited budget, the subset maximizing the risk reduction at the appropriate cost is selected. The developed methodology allows one to analyse the lifeline system characterized by the information related to vulnerability and to their functional model separately and as a whole. The definition of different reference earthquakes is also allowed. The information related to the vulnerability of the elements and to the seism is defined by means of probabilistic models. The present paper is organized as follows. After a brief introduction to the seismic risk associated to a system of lifelines, a synthetic description of the whole methodology adopted is given. In the second part of the paper the methodology developed to assess the risk due to cross-correlations effects between lifelines is described in detail. The problem is assessed from both structural and functional points of view. Results of the application of the whole methodology to test sites are also reported. This work is one of the outcomes of the activities promoted and directed by the Istituto Nazionale di Geofisica e Vulcanologia of Rome within the Programma Operativo di Ricerca per la Sismologia e l’Ingegneria Sismica (PRO.S.I.S.), aimed at assessing methods and instrumentations for the reduction of the seismic risk in Italy.

Seismic risk in Italy for earthquakes of intensity IX (Mercalli scale)

In this report the yearly probability of an earthquake of intensity IX (Mercalli scale) in any area in Italy and the error at 95% of confidence have been evaluated; for the purposes of this evaluation, Italy has been divided into small areas separated by a distance of 3' both in latitude and in longitude. To evaluate the yearly probability, two atenuation curves for volcanic earthquakes and a series of probabilistic curves for tectonic earthquakes have been determined on the basis of about 700 earthquakes, for which it has been possible to draw isoseisms. Isoprobability and equal-error curves have been drawn up on a 1: 1,000,000 scale map.