23 research outputs found
Probability hazard map for future vent opening at Etna volcano (Sicily, Italy).
We evaluate a probability hazard map for future vent opening at Etna volcano using a data set of flank vents spanning last 4.0 ka
Structural health monitoring and earthquake early warning: preliminary studies for application in eastern Sicily
In this work, the reduction of seismic hazard in eastern Sicily is addressed by both studying the fundamental resonant frequency of strategic
buildings through low cost geophysical investigation techniques, and exploring a practical approach to earthquake early warning EEW)
system. The fundamental period and the corresponding amplification of some selected strategic buildings has been estimated using ambient
vibration and earthquake data. We analyzed the basic dynamic parameters of buildings chosen as target, by using continuous vibration
measurements at different floors. The dynamic behavior of structures was evaluated considering both small strains induced by
ambient vibrations and larger excitation levels due to the earthquakes occurrence.
A practical approach to earthquake early warning in the investigated area was dealt with by using empirical relationships between parameters
measured on the initial portion of seismic recordings and related to the earthquake magnitude and peak ground motion. In particular,
we performed the first preliminary tests by using empirical relationships calibrated for the considered area and taking into account
the geometry of the existing permanent seismic network deployed in the eastern Sicily. The estimated relationships have been used to
provide onsite warning around a given seismic station and evaluate the potential damaging effects. The joint of EEW system and geophysical
investigation shown in this work may be deemed a useful guide for the future implementation of the in real time seismic monitoring
in the region.This work has been supported by the following
project: “Attività di sviluppo sperimentale finalizzata alla
riduzione del rischio sismico nella Sicilia Orientale” inside the
PO-FESR 2007-2013 Sicilia; MED-SUV funded from the European
Union Seventh Framework Programme (FP7) under Grant agreement
n°308665. This work is sponsored by European Union’s
Horizon 2020 research and innovation programme under the
Marie Sklodowska-Curie grant agreement n° 798480. We are
thankful to Salvatore Rapisarda and Danilo Contrafatto to support
us in the field work
Seismic amplification effects and soil, to, structure interaction study nearby a fault zone: the Tremestieri fault and Madre Teresa di Calcutta School (Catania)
Results of passive seismic surveys, in terms of both amplification and polarization effects in a section of the Tremestieri Etneo Fault (Sicily
Eastern center - Catania) are discussed. For the purpose, velocimetric and accelerometric records of seismic ambient noise were analyzed.
The polarization analysis of particle motion was performed and azimuthally dependent resonant frequencies were estimated. Ambient
noise data were also used to assess the dynamic properties of a reinforced concrete building, located on the fault zone. The fundamental
modes have been estimated through ambient noise recordings acquired by three-directional accelerometers, installed at the highest
accessible floor and outside the building. The study revealed a clear oriented seismic amplification in the fault zone. This effect was observed
in intensely jointed rock masses, located inside the fault area, as the result of specific geometries and significant directional
impedance contrasts characterizing the area under study. The analyses show that the direction of the largest resonance motions has
transversal relationship with the dominant fracture orientation. The directional amplification is inferred to be produced by stiffness
anisotropy of the fault damage zone, with larger seismic motions high angle to the fractures. The results obtained are in complete agreement
with those obtained by a previous study which analyzed the fault section located to the north-west.Finally, comparing the dynamic
properties of the school building and the vibrational characteristics of the soil in the direction of maximum amplification, no clear resonant
effect in the soil-structure interaction has been observed.This paper has been funded by the following
research projects: “Attività di sviluppo sperimentale finalizzata
alla riduzione del rischio sismico nella Sicilia
Orientale” inside the PO-FESR 2007-2013 Sicilia; MED-SUV
funded from the European Union Seventh Framework Programme
(FP7) under Grant agreement n°308665. This work is
sponsored by European Union’s Horizon 2020 research and innovation
programme under the Marie Sklodowska-Curie grant
agreement n° 798480
Seismic Hazard Mapping inside the Project SIGMA
The Project SIGMA (Sistema Integrato di sensori in ambiente cloud per la Gestione Multirischio
Avanzata) arises from the fields of Information and Communications Technologies (ICT) and advanced
applications for the control, monitoring and management of high-risk processes of natural and social origin.
SIGMA is a multilevel architecture whose main aim is the acquisition, integration and processing of
heterogeneous data from different sources (seismic, volcanic, meteorologic, hydric, pluvial, car traffic,
marine traffic, and so on) to manage and elaborate risk mitigation strategies which are important for the
emergency management planning. Within the several experimental activities included in the project, there is
the designing and realization of a prototype of application platform specialized to provide the operating
procedures and software to the public administrations and the industrial companies, for constantly
monitoring both the anthropic and natural phenomena in Sicily. In this framework, of course, the seismic risk
analysis plays a very important role since Sicily is one of the Italian regions with high seismic risk.
Seismic risk assessment may be approached in two different ways: i) as average seismic risk of the
buildings and facilities in question during the period considered, combining the vulnerability of different
building types and the seismic hazard for the site, which are then expressed in terms of the effects of the
events derived from an earthquake catalogue that exceed a specified threshold during a given period; ii) as
estimated damage of the buildings and the critical facilities using a scenario input described in terms of the
source parameters of the hypocenter as location, magnitude, and so on.
Here we deal with the hazard calculation through the code CRISIS (Ordaz, Aguilar and Arboleda) and
with the code PROSCEN (PRObabilistic SCENario, [Rotondi and Zonno, 2010]) to obtain earthquake
scenario to be used in the latter approach. Indeed, an earthquake scenario is a planning tool that helps
decision makers to visualize the specific impact of an earthquake based on the scientific knowledge. An
earthquake scenario creates a picture that the members of community can recognize and, at the same time,
improves the communication between the scientific, emergency management and policy communities to
seismic risk reduction
Real-time urban seismic network and structural monitoring by means of accelerometric sensors: Application to the historic buildings of Catania (Italy)
A real-time urban seismic network for seismic and
structural health monitoring is being installed in the city of
Catania (Sicily, Italy). The 27 monitoring stations, specifically
designed and assembled, equipped with a low-noise 3-axial
MEMS accelerometer, are located in 23 high exposure and
vulnerability buildings. In this paper we present the
characteristics of the monitoring station and of the network. In
case of strong seismic events, the system will provide shake maps
to the emergency management centre, and will allow to assess the
health conditions of the monitored buildings. The network is
conceived to be further expandable over the whole historical city
centre of the city of Catania.PublishedMilan, Italy1IT. Reti di monitoraggi
Non-Structural Risk Evaluation: Experiences From Pilot Areas Of The Knowrisk Project
This paper presents a multidisciplinary approach to quantify seismic hazard and ground motion intensity parameters for non-structural seismic risk evaluation. In the framework of the European KnowRISK Project, three pilot areas were selected for testing different methodological approaches aimed at evaluating elements and measures to reduce seismic risk coming along with the failure of non-structural elements. At Mt. Etna, Italy, instrumental and historical macroseismic data are used to generate ground motion time series for different scenario events. Risk maps for non-structural damage are generated by using building vulnerability from census data and a damage model based on fragility curves; interstory drift spectra have been also calculated for a representative test site. In South Iceland, scenarios are defined basing on the June 2000 seismic sequence, which provided strong-motion data at several locations. The recorded data and other parameters of the source are used to perform finite-fault simulations of ground motion at different locations in the area and then to calculate interstory drift spectra. In Portugal a scenario referring to the Lower Tagus Valley was selected and finite-fault simulations for the nearby city of Lisbon were performed.PublishedThessaloniki, Greece5T. Sismologia, geofisica e geologia per l'ingegneria sismic
Source Parameters and Seismic Anisotropy in Tectonically Active Zones: Southeastern Sicily and State of Washington.
Estimation of Earthquake Early Warning Parameters for Eastern Sicily
Earthquake early warning systems (EEWSs) are becoming a suitable
instrument for seismic risk management in real time. In fact, they are implemented
or are undergoing testing in many countries around the world because EEWSs represent
an effective approach to mitigating seismic risk on a short timescale. EEWSs are based
on the use of relationships between some parameters measured on the initial portion of
seismic signal after the onsets. Here, we address the first approach to the implementation
of EEWS in eastern Sicily, a region that has been hit by several destructive earthquakes.
We estimated the peak displacement amplitude of the first portion of P and S waves Pd,
the ground-motion period parameter Ď„c, and the peak ground velocity (PGV) from earthquakes
with ML ≥2:8 recorded by the broadband stations operated by the Istituto Nazionale
di Geofisica e Vulcanologia. We found that the Pd is correlated with the size of
the earthquake and may be used to compute the magnitude for an EEWS in this area.We
also derived the relationships between Ď„c and ML, and between Pd and PGV, which can
be used to provide on-site warning in the area around a given station and to evaluate the
potential damaging effects. These relationships may be deemed a useful guide for future
implementation of the EEWS in the region.Published1464-14774T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa
Probability hazard map for future vent opening at Etna volcano (Sicily, Italy).
We evaluate a probability hazard map for future vent opening at Etna volcano using a data set of flank vents spanning last 4.0 ka.PublishedVienna, Austria4V. Vulcani e ambienteope
Vents Pattern Analysis at Etna volcano (Sicily, Italy).
We evaluate clustering features at Etna volcano using a dataset of flank vents spanning last 4.0 ka.PublishedVienna, Austria2V. Dinamiche di unrest e scenari pre-eruttiviope