8 research outputs found
Strong-Ground-Motion Simulation of the 6 April 2009 L’Aquila, Italy, Earthquake
On 6 April 2009, an earthquake of Mw 6:13 (Herrmann et al., 2011)
occurred in central Italy, close to the town of L’Aquila. Although the earthquake
is considered to be a moderate-size event, it caused extensive damage to the surrounding area. The earthquake is identified with significant directivity effects: highamplitude, short-duration motions are observed at the stations that are oriented along
the rupture direction, whereas low-amplitude, long-duration motions are observed at
the stations oriented in the direction opposite to the rupture. The complex nature of the
earthquake combined with its damage potential brings the need for studies that assess
the seismological characteristics of the 2009 L’Aquila mainshock.
In this study, we present the strong-ground-motion simulation of this particular
earthquake using a stochastic finite-fault model with a dynamic corner frequency approach. For modeling the resulting ground motions, we choose two finite-fault source
models that take into account the source complexity of the L’Aquila mainshock. In
order to test the sensitivity of ground-motion parameters to the seismic wave attenuation parameters, we use two different attenuation models obtained in the study region
using weak-motion and strong-motion databases. Comparisons are made between the
attenuation of synthetics and ground-motion prediction equations (GMPEs). Synthetic
ground motions are further compared with the observed ones in terms of Fourier
amplitude and response spectra at 21 strong-ground-motion stations that recorded
the mainshock within an epicentral distance of 100 km. The spatial distribution of
shaking intensity obtained from the “Did You Feel It?” project and site survey results
are compared with the spatial distributions of simulated peak ground-motion intensity
parameters. Our results show that despite the limitations of the method in simulating
the directivity effects, the stochastic finite-fault model seems an effective and fast tool
to simulate the high-frequency portion of ground motion
Modelling Uncertainties of Italian Code-Conforming Structures for the Purpose of Seismic Response Analysis
Site-specific uniform hazard spectrum in Eastern Turkey based on simulated ground motions including near-field directivity and detailed site effects
In this study, stochastic earthquake catalog of the Erzincan region in Turkey is generated based on synthetic ground motions. Monte Carlo simulation method is used to identify the spatial and temporal distribution of events. Ground motion time histories are generated using stochastic simulation methodology. Annual exceedance rate of each ground motion amplitude is calculated through statistical distribution of the complete set of ground motions. The results are compared with classical probabilistic seismic hazard analysis (PSHA). Classical PSHA generally produces larger spectral amplitudes than the proposed study due to wide range of aleatory variability. The effects of near-field forward directivity and detailed site response are also investigated on the results
Stochastic Strong Ground Motion Simulation of the Southern Aegean Sea Benioff Zone Intermediate‐Depth Earthquakes
Building damage scenarios based on exploitation of housner intensity derived from finite faults ground motion simulations.
In this paper earthquake damage scenarios for residential buildings (about 4200 units) in Potenza (Southern Italy) have been estimated adopting a novel probabilistic approach that involves complex source models, site effects, building vulnerability assessment and damage estimation through Damage Probability Matrices. Several causative faults of single seismic events, with magnitude up to 7, are known to be close to the town. A seismic hazard approach based on finite faults ground motion simulation techniques has been used to identify the sources producing the maximum expected ground motion at Potenza and to generate a set of ground motion time histories to be adopted for building damage scenarios. Additionally, site effects, evaluated in a previous work through amplification factors of Housner intensity, have been combined with the bedrock values provided by hazard assessment. Furthermore, a new relationship between Housner and EMS-98 macroseismic intensity has been developed. This relationship has been used to convert the probability mass functions of Housner intensity obtained from synthetic seismograms amplified by the site effects coefficients into probability mass function of EMS-98 intensity. Finally, the Damage Probability Matrices have been applied to estimate the damage levels of the residential buildings located in the urban area of Potenza. The proposed methodology returns the full probabilistic distribution of expected damage, thus avoiding average damage index or uncertainties expressed in term of dispersion indexes