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A European seismic risk model will be released in 2020 as an output of the European Horizon 2020 SERA project (www.sera-eu.org), building also upon the research efforts of many previous projects (e.g. LESSLOSS, SYNER-G, NERA, SHARE). The main risk metrics that will be released with the model include national and sub-national maps of average annual loss (AAL) and probable maximum loss (PML) and national loss exceedance curves for 46 countries in Europe. Before the release of this model, the performance of its components needs to be extensively evaluated through a number of different tests. This paper provides a brief summary of the current development of the ESRM20 and describes the testing framework that is being set up for the testing of the model. This framework leverages software development and includes unit tests, integration tests, system tests and acceptance tests. Unit tests consider the components of the risk model separately, whereas integration tests check the performance of a group of components together. Example integration tests include history checks where the total losses (fatalities and economic losses) estimated from all events in the European earthquake catalogue since 1980 will be undertaken, and comparisons will be made with the total observed losses and empirically derived annual average losses and loss exceedance curves (with the losses adjusted to today’s value). To constrain the ground motion in the previous test, ShakeMaps for the historical events over the aforementioned period are being used to predict the damage/losses/consequences using the ‘Scenario from ShakeMap’ calculator of the OpenQuake-engine and these are being compared with the reported numbers in loss databases. More detailed verification tests are also being made for events in Italy and Greece for which detailed damage data at the building-by-building level is available. Once the ERSM20 model is released, its components could then be submitted for prospective testing in a new testing centre that is being set up as part of the Horizon 2020 RISE project., The research described herein has received national funding from the 'JRU EPOS Italia' project as well as European funding from the European Union's Horizon 2020 research and innovation programme under grant agreements No 730900 (Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe 'SERA' project) and No 821115 (Real-time Earthquake Risk Reduction for a Resilient Europe 'RISE' project).

In the context of the STREST project (http://www.strest-eu.org/), an engineering multi-level risk-based methodology to stress test critical non-nuclear infrastructures has been developed. This paper summarizes the STREST framework and its exploratory application to six key representative Critical infrastructures in Europe, exposed to variant hazards, namely: a petrochemical plant in Milazzo, Italy, large dams of the Valais region in Switzerland, hydrocarbon pipelines in Turkey, the Gasunie national gas storage and distribution network in Holland, the port infrastructure of Thessaloniki, Greece and an industrial district in the region of Tuscany, Italy. According to the characteristics of each case study, different stress test levels were applied. The application to the selected CIs is presented following the workflow of the methodology, comprised of four phases: Pre-Assessment phase; Assessment phase; Decision phase; and Report phase. First the goals, the method, the time frame, and the appropriate stress test level to apply are defined. The stress test is performed at component and system levels and the outcomes are checked and compared to the acceptance criteria. A stress test grade is assigned and the global outcome is determined by employing a grading system. Finally, critical events and risk mitigation strategies are formulated and reported to stakeholders and authorities.

The recognition of fragility and vulnerability functions as a fundamental tool in seismic risk assessment has led to the development of more and more complex and elaborate procedures for their computation. Although these functions have been traditionally produced using observed damage and loss data, more recent studies propose the employment of analytical methodologies as a way to overcome the frequent lack of post-earthquake data. The variation of the structural modelling approach on the estimation of building capacity has been the target of many studies in the past; however, its influence on the resulting vulnerability model for classes of buildings, the impact in loss estimations or propagation of the uncertainty to the seismic risk calculations has so far been the object of limited scrutiny. In this paper, an extensive study of static and dynamic procedures for estimating the nonlinear response of buildings has been carried out to evaluate the impact of the chosen methodology on the resulting capacity, fragility, vulnerability and risk outputs. Moreover, the computational effort and numerical stability provided by each approach have been evaluated and conclusions drawn regarding the optimal balance between accuracy and complexity. Copyright © 2013 John Wiley & Sons, Ltd. info:eu-repo/semantics/publishedVersion

Risk analysis has a critical role in the reduction of casualties and damages due to earthquakes. Recognition of this relation has led to a rapid rise in demand for accurate, reliable and flexible risk assessment numerical tools and software. As a response to this need, the Global Earthquake Model (GEM) started the development of an open source platform called OpenQuake, for calculating seismic hazard and risk at different scales. Along with this framework, also several other tools to support users creating their own models and visualizing their results are currently being developed, and will be made available as a Modelers Tool Kit (MTK). In this paper, a description of the architecture of OpenQuake is provided, highlighting the current data model, workflow of the calculators and the main challenges raised when running this type of calculations in a global scale. In addition, a case study is presented using the Marmara Region (Turkey) for the calculations, in which the losses for a single event are estimated, as well as probabilistic risk for a 50 years time span.

In this paper the seismic capacity of adobe dwellings, in-plane and out-of-plane, is analyzed in terms of the displacement capacity and the period of vibration. For the former, cyclic and dynamic tests carried out at the Catholic University of Peru (PUCP) has been analyzed to obtain limit states (LS) for adobe walls and damping values for each LS. The period of vibration obtained from the experimental test results were compared with the results of elastic numerical analysis, where different configurations of adobe buildings were simulated. Then, an expression to compute the elastic period of vibration of adobe dwellings was obtained in function of the walls height. For the out-of-plane behaviour the displacement capacity is obtained from a linearized displacement-based approach, which estimates the maximum displacement that an adobe wall can support without collapsing. The period of vibration is obtained based on the collapse mechanism selected for each wall, which is a function of the wall geometrical properties and the boundary conditions.

According to the last national census, 35% of the Peruvian dwellings are made with adobe or tapial (rammed earth). In Cusco, a city located at the Peruvian highlands, around 75% of the building stock is constructed with earth. Besides, Cusco is relatively seismically active and thus seismic risk assessment studies are warranted. For example, on May 21, 1950, an earthquake seriously damaged almost all the buildings in Cusco, which a maximum estimated acceleration of 300 gals. This work looks at the structural properties of adobe buildings in Cusco for use in seismic risk assessment. The geometrical properties of typical dwellings from Cusco have been established according to a building-by-building survey carried out at the Catholic University of Peru (PUCP). Then, a database containing the principal geometrical properties of 30 dwellings has been created which has allowed the mean, standard deviation and probability density functions (PDF) to be defined for parameter such as storey height, wall length, etc.

A procedure to evaluate the seismic vulnerability of one-storey adobe dwellings located in Cusco (Peru) is presented here. The seismic capacity of these dwellings is based on a mechanical-based approach, where the in-plane and out-of-plane failure mechanisms are taken into account. From a database with the principal geometrical properties of dwellings from Cusco, random populations of buildings were generated through Monte Carlo simulation. The capacity of each random dwelling is expressed as a function of its displacement capacity and period of vibration, and this is evaluated for different damage limit states. The seismic demand has been represented by the displacement spectral shapes computed for different levels of intensity, considering the Peruvian Seismic Code and the Eurocode 8. Finally, from the comparison between capacity and demand, probability of failure have been obtained for different return periods.

Risk analysis is a critical link in the reduction of casualties and damages due to earthquakes. Recognition of this relation has led to a rapid rise in demand for accurate, reliable and flexible risk assessment software. However, there is a significant disparity between the high quality scientific data developed by researchers and the availability of versatile, open and user-friendly risk analysis tools to meet the demands of end-users. In the past few years several open-source software have been developed that play an important role in the seismic research, such as OpenSHA and OpenSEES. There is however still a gap when it comes to open-source risk assessment tools and software. In order to fill this gap, the Global Earthquake Model (GEM) has been created. GEM is an internationally sanctioned program initiated by the OECD that aims to build independent, open standards to calculate and communicate earthquake risk around the world. This initiative started with a one-year pilot project named GEM1, during which an evaluation of a number of existing risk software was carried out. After a critical review of the results it was concluded that none of the software were adequate for GEM requirements and therefore, a new object-oriented tool was to be developed. This paper presents a summary of some of the most well known applications used in risk analysis, highlighting the main aspects that were considered for the development of this risk platform. The research that was carried out in order to gather all of the necessary information to build this tool was distributed in four different areas: information technology approach, seismic hazard resources, vulnerability assessment methodologies and sources of exposure data. The main aspects and findings for each of these areas will be presented as well as how these features were incorporated in the up-to-date risk engine. Currently, the risk engine is capable of predicting human or economical losses worldwide considering both deterministic and probabilistic-based events, using vulnerability curves. A first version of GEM will become available at the end of 2013. Until then the risk engine will continue to be developed by a growing community of developers, using a dedicated open-source platform.

This paper looks at the structural properties of adobe buildings in Cusco, Peru, for use in seismic risk assessment. The geometrical properties (typology) of adobe dwellings from Cusco have been established according to a building-by-building survey. Cusco has been chosen for this study as, according to the national census, around 80% of the building stock in this town is constructed with adobe. Furthermore, this region of the country is relatively seismically active and thus seismic risk assessment studies are warranted. Additional structural information of adobe buildings has been obtained from experimental tests carried out at the Catholic University of Peru. These tests have allowed the inter-storey drift capacity and the period of vibration of adobe buildings to be derived. A database containing the principal geometrical properties of 30 dwellings has been created which has allowed the mean, standard deviation and probability density functions (PDF) to be defined for each parameter such as storey height, wall length, etc. These properties are of use in a recently proposed probabilistic displacement- based earthquake loss assessment method (DBELA) which generates random populations of buildings based on this input data. The structural capacity of each random building is then predicted based on structural mechanics principles, and by comparing this capacity with the demand from earthquakes, estimates of the probability of damage can be made.