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This paper contains a large-scale seismic assessment of the downtown area of Skikda city in Algeria. This area was identified for the present work based on its importance regarding size and the legacy of older buildings for which information was available. Moreover, seismic microzonation studies for the city of Skikda based on the simulation of local effects are available. This paper aims to evaluate the seismic risk in the old part of Skikda using the Risk-UE LM1 methodology, namely, the empirical method LM1 based on an in situ survey. Damage probability matrices have been obtained for the deterministic (historical events) and probabilistic earthquake scenarios (i.e., characterized by a return period), in accordance with the city's microzoning study. The results of the seismic risk assessment in the city are represented by damage to buildings. Thus, physical damage was also used as a hazard-related variable to predict economic and human losses, and other quantities, such as restoration cost and quantities of debris, were studied. Despite the moderate seismic risk in Skikda, the results show a high risk due to the high exposure and vulnerability of the buildings, which are generally made up of buildings in unreinforced masonry. Important social and economic losses are expected in these areas as well. The seismic risk of Skikda was estimated as moderate with a predicted number of 83 million USD global economic impacts, including economic losses and restoration costs for a seismic intensity scenario of VII. To better manage and analyze the human and economic exposure. The seismic risk maps was elaborated to be used as a guide to decision-making to prepare emergency plans for earthquake risk mitigation in Skikda. [ABSTRACT FROM AUTHOR]

On December 29, 2020, nine months after the March Mw 5.4 Zagreb earthquake and amidst the COVID-19 lockdown, a devastating Mw 6.4 earthquake struck near the town of Petrinja, about 50 km SE from the country's capital Zagreb. It was preceded by the Mw 4.9 foreshock from the day before. The main shock claimed 7 fatalities and caused widespread damage. Historical centers of nearby cities with invaluable heritage buildings were significantly affected as were the many residential buildings, built mainly of unreinforced masonry. Damage was observed as far as 60 km from the epicenter. This paper summarizes the seismological aspects of the Mw 6.4 Petrinja earthquake, the emergency response and the main impacts to people and buildings. The description and findings are based on the field observations and a series of post-earthquake activities led by the team of the Faculty of Civil Engineering, University of Zagreb. Typical damage to buildings and usability data are presented with examples based on 50,000 inspection results. By far the most affected were the unreinforced masonry buildings, followed by confined masonry, whereas reinforced concrete buildings were the least affected. The total direct and indirect losses are estimated to 4.8 billion EUR. The provided information represents a useful basis and impetus for improving emergency action and long-term disaster reduction plans in other regions with similar building exposure and seismotectonic settings. [ABSTRACT FROM AUTHOR]

The regional seismic risk assessment plays an important role in the disaster prevention and mitigation. The accurate time-history analysis for a region provides an important data base for regional seismic risk assessment. However, an accurate calculation method is limited, then, its accuracy still lacks validation. Meanwhile, there is also a lack of risk assessment methods and indicators applicable to the regional accurate time-history analysis, both of which hinder the seismic risk assessment. In this paper, a regional-scale time history analysis-driven method is proposed for the quantitative evaluation of regional seismic damage risk and verified with a real earthquake damage survey. First, the regional time history analysis method is introduced, including the automatic modeling, response calculating, result analysis and 3-D visualization modules. Second, a calculation method for seismic damage degrees (DD) of buildings is introduced. Subsequently, the probabilistic models of each DD under the ground motions with a specific intensity are calculated based on regional-scale nonlinear time history analysis. Next, the concept of the three-level seismic damage risk is offered, then a determining workflow of seismic damage risks is proposed based on the code-abiding three-level design requirement. Afterward, the regional seismic damage index is suggested for the quantitative evaluation of earthquake-induced damage risk. Finally, the actual seismic damage database of 192 buildings in epicenter of Ludian Earthquake is established through on-site investigations, then used to verify the regional simulation's accuracy. Consequently, it could be an aid to accurately present seismic damage distribution assessments and effectively develop seismic risk mitigation strategies. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to quantify a proposed parameter defined as expected annual seismic resilience, which takes into account all possible events that affect a site of interest by following the next steps: (1) definition of seismic hazard, (2) definition of the exposure database, (3) computation of structural and human vulnerability, (4) estimation of seismic risk, (5) definition of rehabilitation strategies and (6) estimation of repairing times and required resources in the proposed rehabilitation process. In this study, consequential physical losses and indirect cost are not considered in the resilience computation. The methodology is applied to a case study of existing school buildings, located in Mexico City given its important seismic activity. The results are presented in annual resilience maps that will allow to graphically observe the distribution of resilient structures and use this information to take better decisions in disaster prevention and response. From this research it was found that a large percentage of the studied school buildings do not achieve an acceptable annual resilience value according to the rating proposed, which is important, since the seismic design codes do not explicitly consider resilience concepts. However, with the information of expected annual seismic resilience values in Mexico City, obtained in this research, it is possible to identify those buildings that require immediate attention associated to the lower resilience values so that they may be taken into consideration in the decision-making process of disaster prevention and response. [ABSTRACT FROM AUTHOR]

In the aftermath of a seismic event, decision-makers have to decide quickly among alternative management actions with limited knowledge on the actual health condition of buildings. Each choice entails different direct and indirect consequences. For example, if a building sustains low damage in the mainshock but people are not evacuated, casualties may occur if aftershocks lead the structure to fail. On the other hand, the evacuation of a structurally sound building could lead to unnecessary financial losses due to business and occupancy interruption. A monitoring system can provide information about the condition of the building after an earthquake that can support the choice between several competing alternatives, targeting the minimization of consequences. This paper proposes a framework for quantifying the benefit of installing a permanent seismic structural health monitoring (S2HM) system to support building evacuation operations after a seismic event. Decision-makers can use this procedure to preventively evaluate the benefit of an SHM system and decide about the worthiness of its installation. [ABSTRACT FROM AUTHOR]

This paper presents an analytical method for large-scale vulnerability assessment used in order to simulate damage scenarios corresponding to those observed during past earthquakes in Italy. The method, already published in the technical literature with the acronym SP-BELA (Simplified Pushover-Based Earthquake Loss Assessment), has been adopted to calculate the vulnerability of the Italian building stock classified as reinforced concrete and masonry buildings. The current paper describes the calibration of the method through the comparison of numerically calculated damage scenarios and data on observed damage collected during earthquakes occurred in Italy starting from the 1976 Friuli earthquake. The use of observed damage data allowed to validate the method and to add reliability to the calculation of damage scenarios. The damage scenarios are useful to plan the emergency response immediately after an earthquake. Finally, a Web Geographical Interface System tool that implements SP-BELA to calculate seismic risk and real time damage scenario is presented. [ABSTRACT FROM AUTHOR]

This paper presents the probabilistic seismic demand and fragility analyses of a novel mid-rise large-span cassette structure. A newly designed nine-storey office building in Hunan, China, is selected, and its two different design schemes, namely, a traditional frame structure and a novel cassette structure, are examined using numerical models established on the basis of a shake table test. Based on probabilistic seismic theory, the appropriate intensity measures are firstly studied based on a set of 110 seismic records; and PGV and GeoSaavg, which consider the 3D characteristics of the structure, are selected. In addition, the uncertainty of earthquakes, including spectral characteristics, fault distance and input direction, are considered, and 25 seismic records recommended by the Federal Emergency Management Agency are selected. An incident angle interval of 22.5° is selected to consider the uncertainty in the input directions of real earthquakes. Incremental dynamic analyses are conducted, and the structural responses in every individual input direction as well as in all the directions are studied. Finally, probabilistic seismic fragility analysis is conducted, and the probabilities of exceeding different limit states of the frame and cassette structures is presented. Amongst the studies, the novel cassette design can not only achieve much larger span, but also shows a better, more stable seismic performance. Therefore, the cassette structure may be a better alternative in seismic design. [ABSTRACT FROM AUTHOR]

The collapse risk of building structures has been one of the major factors causing casualties and huge economic losses for earthquake disaster prevention. This paper presents a shaking table test on low-rise steel moment frames with consideration of mass irregularity in the elevation direction. The frames are subjected to naturally observed and artificial seismic waves. As indicated from the test results, the specimen with the irregularity of additive-mass (additional 5% of the roof mass) on the top floor showed considerable amplification on the acceleration and drift responses at the bottom storey when subjected to over-design earthquakes. A numerical model with degraded stress–strain relation is built in terms of fiber elements and calibrated by test results. Incremental dynamic analyses are performed to evaluate the probabilities exceeding three limit states related to immediate occupancy, life safety, and collapse prevention. The seismic fragility curves through a suite of near-fault ground motions in the Uemachi area of Osaka are obtained for the numerical models with and without mass irregularity on the roof, and the vertical mass irregularity tends to play significant roles in the seismic design for collapse prevention. [ABSTRACT FROM AUTHOR]

The seismic vulnerability assessment of old masonry buildings is essential not only to buildings with recognised historical and heritage value but also to ordinary residential masonry buildings. Thus, and resorting a wide set of damage data collected after the 1998 Azores earthquake, this paper addresses the topic of the seismic vulnerability assessment of traditional masonry buildings through the calibration and application of a simplified vulnerability assessment method to the old city centre of Horta (Faial Island), in Portugal. In this case study, 192 buildings were assessed using this methodology, and vulnerability and loss scenarios were analysed using an integrated Geographical Information System tool. As is discussed in this paper, such procedure could allow city councils or regional authorities to plan interventions based on a global view of the site under analysis, leading to more accurate and comprehensive risk mitigation strategies, which can than support the requirements of safety and emergency planning. [ABSTRACT FROM AUTHOR]

Seismic microzonation represents a basic tool for local administrations in the developing of cost-effective risk reduction strategies and emergency planning. In recent years, the Italian scientific community has been deeply involved in implementing best-practices and tools to make seismic microzonation studies affordable by allowing its widespread application. Specific guidelines were provided that are representative of the international state of the art in this field. Moreover, the national Center for Seismic Microzonation and its applications (CentroMS) was established, which includes the most important Italian scientific institutions involved in seismic microzonation studies during last years. One of the purposes of this Center is supporting local Authorities and professionals in the field practice. Effectiveness of this organization has been tested during most recent seismic sequences, where the Center was charged to support the development of reconstruction plans. In this review paper the main features of these activities are addressed by focusing on experiences gained in the seismic microzonation studies carried out at 138 Municipalities in the area of Central Italy damaged by the 2016–2017 seismic sequence. [ABSTRACT FROM AUTHOR]

Site effects in consequence of the 2016–2018 Central Italy seismic sequence "marked the fate" of many villages located close to the epicenters along the Apennine chain. Pescara del Tronto, a small settlement located on a mountain slope in the municipality of Arquata del Tronto, (AP) is very representative of such territories since, early after the onset of the seismic sequence, suffered very impressive site effects, including a large seismically-induced debris flow and a high number of small volume landslides. This paper describes the main results of the scientific activities carried out by the authors in this locality in the framework of the unprecedented large-scale Seismic Microzonation project funded by Italian Government in Central Italy for 138 territories. Through an intense field activity, the geological and geomorphologic setting of the study area were revised and updated, including a landslide susceptibility assessment that helped the Italian Department of Civil Protection in the emergency management for temporary housing and, later on, was included in the 3rd Level Seismic Microzonation study implemented by authors while the seismic sequence was still ongoing. A very detailed and reliable subsoil model for this municipality was defined, despite difficulties faced in performing direct and indirect investigations due to the safety restrictions for many areas. The Local Seismic Site response was finally assessed for this locality and the results discussed. A key role in the occurrence of strong site effects into Pescara del Tronto has been played by quaternary deposits having an unexpected heterogeneity under the old village. [ABSTRACT FROM AUTHOR]

Assessment of seismic vulnerability in urban areas is a challenging task that requires a meticulous and systematic approach. Sarajevo and Banja Luka, together with Tuzla, are the most urbanized and densely populated cities in Bosnia and Herzegovina. Sarajevo and Banja Luka experienced devastating earthquakes in 1962 and 1969, respectively. This is why it is of the utmost importance to conduct seismic vulnerability evaluation of the existing building stock in Bosnia and Herzegovina. Until today no systematic database regarding structures and their typology has been compiled for the territory of Bosnia and Herzegovina in connection with their vulnerability to seismic actions. The choice of an appropriate vulnerability method plays a key role in the process of assessment of seismic risk and highly depends on the available information, characteristics of the buildings, organization of data collection and decision-makers. Among various methods, it was decided to use the macroseismic method derived from the EMS-98 scale for the vulnerability assessment of the existing buildings in Bosnia and Herzegovina. The database was obtained from the "typology of residential buildings in the BiH" project, a comprehensive survey of 13,044 existing residential buildings in BIH, which was conducted for energy performance assessment of the national building stock. For the purpose of this research, the database was reduced to a sample of 2933 buildings, as it included a selection of only unreinforced and confined masonry buildings built from 1918 to 2014 and located in Sarajevo and Banja Luka. The aim of this paper is to provide an overture in assessing the seismic risk in Sarajevo and Banja Luka by applying the method based on the vulnerability index. The vulnerability index is calculated by the macroseismic method which is in the function of the type of building, regional vulnerability factor and behavior modifier factors. The application of this method confirms the notable seismic risk in the cities of Sarajevo and Banja Luka due to the high vulnerability of the buildings. It may be argued that the behavior modifiers which had the largest impact on the change of the vulnerability class were the number of floors and type of roof structure. This research intends to contribute to the prevention of an earthquake disaster, in the form of a theoretical forecast of the aftermath: structural damage and/or socio-economic losses that may occur after an earthquake. [ABSTRACT FROM AUTHOR]

This paper describes a rapid response and risk mitigation system Istanbul Natural Gas Distribution Network Seismic Risk Reduction Project (IGRAS) for the Istanbul Natural Gas Network (IGDAŞ). Upon the trigger signal received from the earthquake early warning system in Istanbul, the real-time algorithm at IGRAS system district regulators checks the threshold levels of ground-motion parameters and interrupts the gas flow if any exceedance is detected. Then the system: (1) produces almost real-time earthquake hazard maps by using on-line strong-motion data from the strong-motion network in Istanbul: (2) estimates the distribution of damage to the natural gas network; and (3) transfers these damage distribution maps to stakeholders to enable dispatching rapid response teams to high damage areas. [ABSTRACT FROM AUTHOR]

The seismic zoning map of Turkey that is used in connection with the national seismic design code (versions issued both in 1997 and 2007) is based on a probabilistic seismic hazard assessment study conducted more than 20 years ago (Gülkan et al. in En son verilere göre hazırlanan Türkiye deprem bölgeleri haritası, Report No: METU/EERC 93-1, 1993). In line with the efforts for the update of the seismic design code, the need aroused for an updated seismic hazard map, incorporating recent data and state-of-the-art methodologies and providing ground motion parameters required for the construction of the design spectra stipulated by the new Turkish Earthquake Design Code. Supported by AFAD (Disaster and Emergency Management Authority of Turkey), a project has been conducted for the country scale assessment of the seismic hazard by probabilistic methods. The present paper describes the probabilistic seismic hazard assessment study conducted in connection with this project, incorporating in an area source model, all recently compiled data on seismicity and active faulting, and using a set of recently developed ground motion prediction equations, for both active shallow crustal and subduction regimes, evaluated as adequately representing the ground motion characteristics in the region. The area sources delineated in the model are fully parameterized in terms of maximum magnitude, depth distribution, predominant strike and dip angles and mechanism of possible ruptures. Resulting ground motion distributions are quantified and presented for PGA and 5 % damped spectral accelerations at T = 0.2 and 1.0 s, associated with return periods of 475 and 2475 years. The full set of seismic hazard curves was also made available for the hazard computation sites. The second part of the study, which is based on a fault source and smoothed seismicity model is covered in Demircioglu et al. in Bull Earthq Eng, (2016). [ABSTRACT FROM AUTHOR]

A comprehensive comparison among the three strongest earthquakes occurred in Italy in the past 30 years is presented. These three earthquakes struck the regions of Umbria and Marche in 1997, Abruzzo in 2009, and Emilia-Romagna, Lombardia and Veneto in 2012, respectively. They were assigned exactly the same local magnitude, Ml5.9, and comparable focal depths. In spite of having occurred in the same country, these earthquakes displayed considerable differences from both the scientific and the civil protection points of view. Differences can be ascribed to the released energy, the seismotectonic and geomorphological features, as well as the diverse population density, building features and socio-economic conditions that characterize the three epicentral areas. Nevertheless, the overall economic losses come out to be almost the same, although deriving from quite diverse distributions among the different categories of costs. Differences and similarities among the three events are carefully analysed and discussed in the paper. [ABSTRACT FROM AUTHOR]

The seismic vulnerability assessment of old masonry buildings is essential not only to buildings with recognised historical and heritage value but also to ordinary residential masonry buildings. This paper approaches the seismic vulnerability assessment of masonry buildings by applying a simplified methodology to the old city centre of Seixal in Portugal. The methodology adopted in this study was based on a vulnerability index used for the evaluation of damage and the study of loss scenarios on a large scale. Over 500 buildings were assessed using this methodology, and the results were analysed using an integrated Geographical Information System tool. The integration of the vulnerability and loss results could allow city councils or regional authorities to plan interventions based on a global view of the site under analysis, leading to more accurate and comprehensive risk mitigation strategies that support the requirements of safety and emergency planning. [ABSTRACT FROM AUTHOR]

In this paper we present a site effects analysis carried out in Málaga city's historical centre (Southern Spain). Two different methodologies have been used: an experimental technique using ambient noise measurements and a 1D numerical method. Soil fundamental frequencies have been obtained from the first technique, and soil transfer functions have been calculated from the numerical methodology. In order to use these results in vulnerability studies, intensity increments for each type of soil have also been estimated. From this information, a seismic microzonation has been proposed for the city centre, classified in six types of soils. Soil fundamental frequencies vary between above 5.0Hz at the hills of the city (where rock arises on the surface), and 1.0Hz near Guadalmedina river. The results show regions with high intensity increments (ΔI = +1.5) corresponding to areas which suffered heavy damage in the 1680 earthquake (I = VIII-IX). Moreover, most of the monuments and historical buildings in the city are located in these high risk areas. Results underline the importance of this kind of studies for seismic risk mitigation, historical preservation and emergency planning in the main cities' historical centres. [ABSTRACT FROM AUTHOR]

The earthquake occurred on the 6th of April 2009 in the Abruzzo Region of Italy, seriously hit the Cultural Heritage (C.H.) patrimony with major destructive effects on L'Aquila, a city of 70,000 inhabitants with the size and the historical and strategic importance of the Region capital. The emergency activities to protect the C.H. have been developed on two parallel levels: (1) survey and assessment of damages, (2) implementation of temporary safety measures. The organization of the emergency actions was managed by a centralized structure, the so called Function 15 'Protection of Cultural Heritage', that coordinated the surveys of protected buildings and the design and implementation of temporary safety measures. This allowed the cooperation among different involved subjects (Ministry of Cultural Heritage officers, experts on structural engineering, architects and historians from Universities and private offices and fire brigade teams). The first level of the operating process was carried out on site by expert teams filling up dedicated survey forms for churches and palaces, developed by the Civil Protection Group GLABEC (a Working group for Cultural Heritage); the forms were based on the standardization of damage survey allowing for its immediate interpretation. The second level was based on the past experience in the field of temporary safety measures; the idea was to provide a technical and scientific support in order to assist the work of fire brigade, highly experienced professionals in the 'emergency' field. After the first emergency phase the damages of the most important buildings were more carefully investigated and the possible damage progression constantly monitored. The paper presents the case of the Spanish Fortress in L'Aquila, severely damaged by the earthquake; the description concerns the definition of the damages and the interpretation of the activated collapse mechanisms. Finally the design of the provisional strengthening interventions and the on site diagnostic investigations are presented. [ABSTRACT FROM AUTHOR]

The determination of ground motion is crucial to plan the appropriate emergency activities, especially in areas characterised by an intense seismic history like the Italian peninsula. Ground motion assessment is generally based on the seismological parameters reported in the instrumental and parametric seismic catalogues. Therefore, the computation of shaking scenarios of historical earthquakes is very challenging, due to the poorly constrained variables (i.e., magnitudes, epicentral location, seismogenic sources), derived from the macroseismic intensity. In this study, we propose a novel approach to investigate the location and parametrization of the seismogenic sources of historical earthquakes and derive shaking scenarios. To this aim, the ground motion of two historical events, the Fabriano (1741, Mw = 6.1, Imax IX MCS) and Camerino (1799, Mw = 6.1, Imax IX–X MCS) earthquakes is simulated. In order to include the site response, a Vs,30 map of the Umbria and Marche regions is created from near-surface data. Different causative faults solutions are tested, finally discussing the ideal seismogenic source based on the residual analysis between observed and simulated macroseismic intensities. The resultant shaking scenarios of the two events are obtained by integrating observed intensities and simulations. [ABSTRACT FROM AUTHOR]

By integrating the vulnerability index of buildings, earthquake disaster matrix, and historical earthquake disaster data, the vulnerability of typical buildings and compounds in rural areas of China are analyzed. The disaster matrix of buildings in historical earthquakes was obtained by analyzing historical earthquake disaster data. By integrating the historical disaster matrix and vulnerability analysis of typical structures in rural areas, a seismic disaster matrix was established to assess the seismic performance of regional compounds. Combined with the historical earthquake disaster matrix and vulnerability index, the lognormal distribution function was used to analyze the vulnerability index of regional structures and compounds to obtain the disaster matrix of structures under different seismic intensities. Considering the structures and compounds in the rural areas in the Tianjin district as an example, the seismic vulnerability of typical structures was investigated. The regional structure disaster matrix of the study region was established and the vulnerability indices of different types of structures and compounds were obtained to clarify the regional disaster prevention ability. [ABSTRACT FROM AUTHOR]

Catastrophe models are important tools to provide proper assessment and financial management of earthquake-related emergencies, which still create the largest protection gap across all perils. Earthquake catastrophe models include three main components, namely: (1) the earthquake hazard model, (2) the exposure model and, (3) the vulnerability model. Simulating spatially distributed ground-motion fields within either deterministic or probabilistic seismic hazard assessments poses a major challenge when site-related financial protection products are required. In this framework, we develop ad hoc correlation models for different Italian regions (specifically northern, central and southern Italy) and thereafter we perform both deterministic scenario-based and probabilistic event-based hazard and risk assessments in order to advance the understanding of spatial correlations within the catastrophe modelling process. We employ the OpenQuake engine for our calculations. This is an open-source tool suitable for accounting for the spatial correlation of earthquake ground-motion residuals. Our outcomes, albeit preliminary, demonstrate the importance of considering not only the spatial correlation of ground motions, but also its associated uncertainty in risk analyses. Although loss exceedance probability curves for the return periods of interest for the (re)insurance industry show similar trends, both hazard and risk footprints in terms of average annual losses feature less noisy and more realistic patterns if spatial correlation is taken into account. Such results will have implications for (re)insurance companies evaluating the risk to high-value civil engineering infrastructures. [ABSTRACT FROM AUTHOR]

Seismic loss prediction of regional-scale buildings provides key information for disaster management. However, previous seismic loss prediction models ignored the time-lag effect of cost information and adopted rough loss ratios without considering the characteristics of a region and disaster (including GDP, magnitude, focal depth, epicentre intensity, seismic precautionary intensity, and design basic acceleration of ground motion), which prevented the earthquake loss prediction from achieving sufficient forecasting accuracy. This study develops a novel storey-based seismic direct loss prediction model of regional-scale buildings for the pre-earthquake hazard mitigation and post-earthquake disaster responses based on the machine learning approach. Specifically, the multi-factor support vector machine (SVM) model is established to predict loss ratios, and the hybrid model (ARIMA-SVM) composed of the autoregressive integrated moving average (ARIMA) model and SVM is built to forecast unit replacement costs. The results show that the above models can achieve promising forecasting performance. Finally, the prediction framework has been applied to Wangjiang Campus of Sichuan University in China, and the spatial distribution of storey-level seismic damage and losses in this region can be visualized. Importantly, the outcome of this study provides a comprehensive and realistic understanding of future losses in a region, which supports decision makings in disaster mitigation. [ABSTRACT FROM AUTHOR]

In this study, an updated probabilistic seismic hazard assessment (PSHA) of Pakistan region is performed using the procedures developed for the US National Seismic Hazard Maps and the Earthquake Model of the Middle East (EMME14). It is based on the combination of conventional area sources model and the spatially smoothed gridded seismicity model with crustal faults. An updated earthquake catalogue is compiled using several international and national databases. The background seismicity of the study area is modeled using both the area source zones and the spatially smoothed gridded seismicity approach. A total of 110 crustal fault sources are modeled using their geological slip rates obtained from the database developed by the Global Earthquake Model (GEM). The Makran Subduction Zone (MSZ) is also modeled using a combination of inclined area source zone and the spatially smoothed seismicity approach. Several Ground Motion Prediction Equations (GMPEs) developed by the PEER Next Generation Attenuation (NGA) initiative are employed to estimate the hazard at bedrock level. The logic tree procedure is used to deal with the epistemic uncertainties associated with the source models and the GMPEs. The updated hazard maps for the Peak Ground Acceleration (PGA) and Spectral Accelerations (SA) at natural periods of 0.2 s, 1 s and 2 s are developed for the 10% and 2% probability of exceedance in 50 years (DBE and MCE levels, respectively). The hazard curves and Uniform Hazard Spectra (UHS) for several major cities of Pakistan are also presented. The results provide an updated understanding of the seismic hazard in Pakistan. The presented hazard maps, curves and spectra can be used for the structural design of new buildings as well as the performance assessment of existing buildings. They also provide an improved basis for the policy formulation and planning for effective disaster risk reduction in the region. [ABSTRACT FROM AUTHOR]

Physical vulnerability of buildings is one of the key parameters needed to assess earthquake risk and to address appropriate disaster management interventions in earthquake prone countries. In order to evaluate this parameter, appropriate fragility functions prepared based on local construction should be applied. However, in Iran reliable fragility curves for different types of buildings have not been developed yet. To address this issue, 19 sets of fragility curves for different types of buildings of Iran were generated in this study, based on empirical approach, incorporated with statistical analysis. Accordingly, at first, different types of common buildings in Iran such as steel frame, reinforced concrete, and masonry buildings were classified into 19 categories. Then, appropriate fragility curves were generated for each class, using existing empirical fragility curves in Iran as well as those proposed for similar types of buildings in other countries. For this purpose, a statistical approach was adopted to weight different curves based on the construction provisions and expert's judgment. Finally, fragility curves obtained from this study were validated with the observed damages of the previous earthquakes in Iran that shows acceptable compatibility. The proposed approach provides more reliable results for vulnerability assessments in Iran and can be employed in other regions having similar conditions. [ABSTRACT FROM AUTHOR]

How can we evaluate the cost-effectiveness of retrofit interventions aiming at reducing the seismic vulnerability of an existing building? What level of shaking intensity should the retrofitted building sustain? These are open questions affecting either the pre-earthquake prevention, the post-earthquake emergency and the reconstruction phases. The (mis)conception that the cost of retrofit interventions would increase linearly with the level of safety required in designing the intervention often discourages stakeholders to consider alternative retrofit options. As a result, a minimum (in some cases prescribed by-law) level of safety is often targeted, leading in some cases to no-action. Furthermore, the performance measure enforcing owners to take action is generally evaluated following a deterministic approach. When the assessment does not directly reflect, even in simplified terms, epistemic uncertainties and aleatory randomness, it can result in misleading confidence on the expected performance. The present study aims at contributing to the delicate decision-making process of retrofitting existing structures, by developing a framework to assist stakeholders with the evaluation of the actual improvement of the performance, expressed in terms of reduction of collapse probability, of alternative strategies of intervention as well as targeted retrofit levels. With reference to a pre-1970 case study building located in New Zealand, alternative retrofit solutions are considered, targeting different levels of performance, and the probability of reaching collapse when considering a set of ground-motions is evaluated, providing a correlation between the deterministic safety index adopted in the design phase (named "Percentage of New Building Standard" adopting New Zealand regulations) and the expected annual probability of collapse. [ABSTRACT FROM AUTHOR]

One of the key objectives of the new EU civil protection mechanism is an enhanced understanding of risks the EU is facing. Developing a European perspective may create significant opportunities of successfully combining resources for the common objective of preventing and mitigating shared risks. Risk assessments and mapping represent the first step in these preventive efforts. The EU is facing an increasing number of natural disasters. Among them earthquakes are the second deadliest after extreme temperatures. A better-shared understanding of where seismic risk lies in the EU is useful to identify which regions are most at risk and where more detailed seismic risk assessments are needed. In that scope, seismic risk assessment models at a pan-European level have a great potential in obtaining an overview of the expected human and economic losses using a homogeneous quantitative approach and harmonized datasets. This study strives to demonstrate the feasibility of performing a seismic risk assessment at a pan-European level with an open access methodology and using open datasets available across the EU. It also aims at highlighting the challenges and needs in datasets and the information gaps for a consistent assessment of seismic risk at the pan-European level. Results are expressed as expected casualties and economic losses for a return period of 475-year. The study constitutes a 'proof of concept' that can complement the information provided by Member States in their National Risk Assessments. Its main contribution lies in pooling open-access data from different sources in a homogeneous format, which could serve as baseline data for performing more in depth risk assessments in Europe. [ABSTRACT FROM AUTHOR]

The OSS (acronym of the Italian name 'Osservatorio Sismico delle Strutture') is a network of permanent seismic monitoring systems installed in public buildings, and also in some bridges and a dam. Each system consists of a number of sensors sufficient to completely describe the dynamic behaviour of the structure. Structural typologies have been selected according to their representativeness of the public building stock and to their importance for the emergency management. Some relevant aspects are addressed, including: (i) a brief description of the network, (ii) a résumé of data usually collected and organized for each structure (structural survey and in situ tests on materials, experimental modal analysis, FEM models and structural identification) and (iii) a description of data management tools and procedures (network operation performance, post-earthquake automatic analysis, public access to data). At the end, on-going and future use of OSS data is briefly discussed, with reference to statistical analysis of relevant parameters of the available records, real-time post-earthquake damage assessment and an in-field reconnaissance visit after a recent earthquake. [ABSTRACT FROM AUTHOR]

Operational earthquake forecasting (OEF) relies on real-time monitoring of seismic activity in an area of interest to provide constant (e.g., daily) updates of the expected number of events exceeding a certain magnitude threshold in a given time window (e.g., 1 week). It has been demonstrated that the rates from OEF can be used to estimate expected values of the seismic losses in the same time interval OEF refers to. This is a procedure recently defined as operational earthquake loss forecasting (OELF), which may be the basis for rational short-term seismic risk assessment and management. In Italy, an experimental OELF system, named MANTIS-K, is currently under testing. It is based on weekly rates of earthquakes exceeding magnitude (M) 4, which are updated once a day or right after the occurrence in the country of an M 3.5+ earthquake. It also relies on large-scale structural vulnerability and exposure data, which serve to the system to provide continuously the weekly expected number of: (1) collapsed buildings, (2) displaced residents, and (3) casualties. While the probabilistic basis of MANTIS-K was described in previous work, in this study OELF is critically discussed with respect to three recent Italian seismic sequences. The aim is threefold: (1) illustrating all the features of the OELF system in place; (2) providing insights to evaluate whether if it would have been a useful additional tool for short-term management; (3) recognizing common features, if any, among the losses computed for different sequences. [ABSTRACT FROM AUTHOR]

Our children are the future: their school buildings must be safe in the face of natural hazards and children must be empowered with an understanding of natural hazards and actions they can take to be better prepared for the next 'event'. With respect to natural hazards, educational institutions have dual roles of caretakers who must ensure the safety of students in their charge and teachers responsible for educating students about natural hazards. This article presents a comparative study on earthquake risk reduction efforts in primary and secondary schools, based on surveys conducted in areas of varying seismic hazard in Iceland, Italy, and Portugal. The study evaluated the degree to which local authorities were involved in the dissemination of earthquake risk and hazard mitigation information, and specifically how this information was channelled to schools. Vulnerability mitigation for school building interiors (contents) and efforts towards educating pupils towards a culture of safety were also measured. In addition the article presents the risk reduction efforts implemented in Icelandic institutions that serve groups who are especially vulnerable in emergencies and compares those efforts with the efforts made in schools. [ABSTRACT FROM AUTHOR]

To comply with the need to spread the culture of earthquake disaster reduction, we rely on strategies that involve education. Risk education is a long-term process that passes from knowledge, through understanding, to choices and actions thrusting preparedness and prevention, over recovery. We set up strategies for prevention that encompass child and adult education, as a bottom-up approach, from raising awareness to reducing potential effects of disruption of society. Analysis of compulsory school education in three European countries at high seismic risk, namely Portugal, Iceland and Italy, reveals that generally there are a few State-backed plans. The crucial aspects of risk education concerning natural hazards are starting age, incompleteness of textbooks, and lack of in-depth studies of the pupils upon completion of their compulsory education cycle. Hands-on tools, immersive environments, and learn-by-playing approaches are the most effective ways to raise interest in children, to provide memory imprint as a message towards a culture of safety. A video game, Treme- treme, was prepared to motivate, educate, train and communicate earthquake risk to players/pupils. The game focuses on do's and don'ts for earthquake shaking, and allows children to think about what might be useful in the case of evacuation. Education of the general public was addressed using audio-visual products strongly linked to the social, historical and cultural background of each country. Five videos tackled rising of awareness of seismic hazards in Lisbon, the area surrounding Reykjavik, Naples, and Catania, four urban areas prone to earthquake disasters. [ABSTRACT FROM AUTHOR]

Dissemination of knowledge should be a core objective for scientists who work with communities exposed to natural disasters. This task requires the spread of knowledge, to make the public aware in a simple, easy-to-understand, manner, yet without any loss of accuracy. 'Urban Disaster Prevention Strategies using Macroseismic Fields and Fault Sources' (UPStrat-MAFA) was a European project devoted to the implementation of strategies for urban disaster prevention of several aspects of seismic hazard, including the damage state and the earthquake impact. The project carried out numerous outreach activities for the public and stakeholders, to encourage the development of a bottom-up strategy towards disasters mitigation. Here we provide a description of actions that have been aimed at: (1) ensuring effective dissemination and communication of the project outcomes, also after its completion; and (2) raising public awareness and understanding in countries exposed to earthquake hazard. [ABSTRACT FROM AUTHOR]

The 2013 European Seismic Hazard Model (ESHM13) results from a community-based probabilistic seismic hazard assessment supported by the EU-FP7 project 'Seismic Hazard Harmonization in Europe' (SHARE, 2009-2013). The ESHM13 is a consistent seismic hazard model for Europe and Turkey which overcomes the limitation of national borders and includes a through quantification of the uncertainties. It is the first completed regional effort contributing to the 'Global Earthquake Model' initiative. It might serve as a reference model for various applications, from earthquake preparedness to earthquake risk mitigation strategies, including the update of the European seismic regulations for building design (Eurocode 8), and thus it is useful for future safety assessment and improvement of private and public buildings. Although its results constitute a reference for Europe, they do not replace the existing national design regulations that are in place for seismic design and construction of buildings. The ESHM13 represents a significant improvement compared to previous efforts as it is based on (1) the compilation of updated and harmonised versions of the databases required for probabilistic seismic hazard assessment, (2) the adoption of standard procedures and robust methods, especially for expert elicitation and consensus building among hundreds of European experts, (3) the multi-disciplinary input from all branches of earthquake science and engineering, (4) the direct involvement of the CEN/TC250/SC8 committee in defining output specifications relevant for Eurocode 8 and (5) the accounting for epistemic uncertainties of model components and hazard results. Furthermore, enormous effort was devoted to transparently document and ensure open availability of all data, results and methods through the European Facility for Earthquake Hazard and Risk (). [ABSTRACT FROM AUTHOR]

On May 2012, a severe seismic sequence occurred in the central part of the Po Plain (Northern Italy). It was characterized by two main shocks displaying local magnitudes 5.9 (on May 20th) and 5.8 (on May 29th), respectively; the maximum observed intensity was VII-VIII on the MCS scale. The emergency response was coordinated as usual by the Department of Civil Protection (DPC), within the general framework provided by the components and operational structures of the National Civil Protection Service. In addition to the search and rescue and to the population assistance activities, many technical activities were carried out to support the civil protection management of the recovery phase. Among these, mentioning is deserved by: the acquisition and dissemination of the accelerometric data from the National Accelerometric Network and the Seismic Observatory of the Structures, owned and operated by DPC; the evaluation of the liquefaction phenomena; the damage and building safety assessment; the regulations for the seismic safety assessment of industrial buildings, aimed at a rapid re-establishment of the productive activities; the actions undertaken following the evaluations by the Grandi Rischi Commission on the possible evolution of the seismic sequence. All these aspects will be examined under a civil protection perspective. [ABSTRACT FROM AUTHOR]

The article offers information on the study carried on the topic titled "Seismic microzonation of Palatine hill, Roman Forum and Coliseum Archaeological Area." The topics discussed include seismic safety evaluation of architectural heritage buildings in Italy, earthquake risk mitigation studies, and use of information from Seismic microzonation for urban planning and land use management, emergency planning, and reconstruction after an earthquake.

The objective of this study is to evaluate the seismic hazard in Eastern Marmara Region using an improved probabilistic seismic hazard assessment methodology. Two significant improvements over the previous seismic hazard assessment practices are accomplished in this study: advanced seismic source characterization models in terms of source geometry and recurrence relationships are developed, and improved global ground motion models (NGA-W1 models) are employed to represent the ground motion variability. Planar fault segments are defined and a composite magnitude distribution model is used for all seismic sources in the region to properly represent the characteristic behavior of the North Anatolian Fault without the need for an additional background zone. Multi-segment ruptures are considered using the rupture model proposed by the Working Group on California Earthquake Probabilities (). Events in the earthquake catalogue are attributed to the fault zones and scenario weights are determined by releasing the accumulated seismic energy. The uniform hazard spectra at 10 % probability of exceedance in 50 years hazard level for different soil conditions (soil and rock) are revealed for specific locations in the region (Adapazarı, Düzce, Gemlik, Izmit, Iznik and Sapanca). Hazard maps of the region for rock site conditions at the selected hazard levels are provided to allow the readers perform site-specific hazard assessment and develop site-specific design spectrum for local site conditions. [ABSTRACT FROM AUTHOR]

The opportunity and the advantages of applying base isolation technologies developed for civil structures to small objects are investigated and some considerations related to the scale effects are discussed. A series of experimental tests carried out at SRMD facility in San Diego are presented with the aim to investigate the dynamic response of a system designed to simulate a sculpture isolated by means of Double Concave Curved Surface Sliders. Such devices are specifically re-designed to fit the peculiar situation of light weight objects. In particular the samples used in the experimentation are designed with geometric and inertia characteristics fit for representing the Michelangelo's sculptures exposed at the 'Galleria dell'Accademia' in Florence, Italy. Finally, the main aspects concerning the numerical simulation of the seismic response of the proposed isolated system are discussed, also to investigate the efficiency of the existing numerical models, which are developed for traditional devices, when they are applied on such small and particular objects. The results of the experimental/numerical campaign show a general efficiency of the isolation system in terms of limiting the transferred action. Further study is needed to understand more clearly some local unexpected phenomena emerged from the experimental tests. [ABSTRACT FROM AUTHOR]

A field reconnaissance mission was led to the areas affected by the disaster caused by the Magnitude 7.9 earthquake event of 15/08/2007 near the city of Pisco in Peru. The main objectives of the mission were to collect data and make observations leading to improvements in design methods and techniques for strengthening and retrofit, and to assist the phase of reconstruction. The mission focused on the behaviour of non-engineered structures, in particular those of adobe constructions. The findings of the mission confirmed that most of the damage was observed on adobe houses constructed with traditional non anti-seismic techniques which either collapsed or nearly collapsed, causing 519 deaths, 1,366 injuries and more than 58,000 houses destroyed. The mission also confirmed that buildings constructed according to modern earthquake resistant design standards performed with no evident damage. All the parties contacted during the mission, especially the EC Delegation, showed particular interest in the results of the present mission report, which will be taken into consideration when planning the reconstruction phase, especially of the most distant rural areas, where close collaboration between the Governmental Institutions, International Organizations, Universities and NGO’s, will be needed to assist the population for the adoption of earthquake resistant designs in the reconstruction of the destroyed houses. [ABSTRACT FROM AUTHOR]