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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).

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.

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.

Interest in small-to-medium magnitude earthquakes and their potential consequences has increased significantly in recent years, mostly due to the occurrence of some unusually damaging small events, the development of seismic risk assessment methodologies for existing building stock, and the recognition of the potential risk of induced seismicity. As part of a clear ongoing effort of the earthquake engineering community to develop knowledge on the risk posed by smaller events, a global database of earthquakes with moment magnitudes in the range from 4.0 to 5.5 for which damage and/or casualties have been reported has been compiled and is made publicly available. The two main purposes were to facilitate studies on the potential for earthquakes in this magnitude range to cause material damage and to carry out a statistical study to characterise the frequency with which earthquakes of this size cause damage and/or casualties (published separately). The present paper describes the data sources and process followed for the compilation of the database, while providing critical discussions on the challenges encountered and decisions made, which are of relevance for its interpretation and use. The geographic, temporal, and magnitude distributions of the 1958 earthquakes that make up the database are presented alongside the general statistics on damage and casualties, noting that these stem from a variety of sources of differing reliability. Despite its inherent limitations, we believe it is an important contribution to the understanding of the extent of the consequences that may arise from earthquakes in the magnitude range of study.