Guidelines for typology definition of European physical assets for earthquake risk assessment

It is an essential step in urban earthquake risk assessment to compile inventory databases of elements at risk and to make a classification on the basis of pre-defined typology/taxonomy definitions. Typology definitions and the classification system should reflect the vulnerability characteristics of the systems at risk, e.g. buildings, lifeline networks, transportation infrastructures, etc., as well as of their sub-components in order to ensure a uniform interpretation of data and risk analyses results. In this report, a summary of literature review of existing classification systems and taxonomies of the European physical assets at risk is provided in Chapter 2. The identified main typologies and the classification of the systems and their sub-components, i.e. SYNER-G taxonomies, for Buildings, Utility Networks, Transportation Infrastructures and Critical Facilities are presented in Chapters 3, 4, 5 and 6, respectively.JRC.G.5-European laboratory for structural assessmen

Guidelines for deriving seismic fragility functions of elements at risk: Buildings, lifelines, transportation networks and critical facilities

The objective of SYNER-G in regards to the fragility functions is to propose the most appropriate functions for the construction typologies in Europe. To this end, fragility curves from literature were collected, reviewed and, where possible, validated against observed damage and harmonised. In some cases these functions were modified and adapted, and in other cases new curves were developed. The most appropriate fragility functions are proposed for buildings, lifelines, transportation infrastructures and critical facilities. A software tool was also developed for the storage, harmonisation and estimation of the uncertainty of fragility functions.JRC.G.5-European laboratory for structural assessmen

Code-based seismic performance assessment of high-rise tunnel-form buildings in Turkey

Tunnel-form buildings are one of Turkey’s most common typologies for mass housing projects. They are known for their rapid construction process, relatively lower construction costs and shorter construction time. These structures are mainly composed of lightly reinforced thinsectioned shear walls, coupling beams and slabs and can reach up to 20 stories or even more in some cases. The design of these structures is typically based on force-based linear elastic procedures and relies on the behaviour factor and dominant vibration modes to estimate earthquake forces. Shear walls are designed and detailed according to frame and dual systems regulations. Moreover, the minimum reinforcements required by the code are usually sufficient since the shear wall area to floor area is high. In previous earthquakes, low- and mid-rise tunnelform buildings designed according to current standards exhibited high seismic performance. However, some drawbacks and limitations may characterise the design of taller structures. In this context, the present paper investigates the seismic performance of a 14-storey case study residential tunnel-form building located in Istanbul and considers two editions of the Turkish Building Seismic Code (i.e., the TBSC 2007 and 2018) for the performance assessment. A detailed non-linear finite element (FE) model was developed in OpenSeesPY to perform nonlinear time-history analyses considering a set of natural ground motion records. The numerical model considers the inelastic behaviour of the shear walls through fibre-based distributed plasticity elements aggregated with the bilinear shear response. The elastic response of the FE model was validated against the experimental results from ambient vibration monitoring. The comparative seismic performance assessment shows that the TBSC 2018 results in more severe damage estimation, hence highlighting potential drawbacks of buildings designed with previous standards

Development of inventory datasets through remote sensing and direct observation data for earthquake loss estimation

This report summarizes the lessons learnt in extracting exposure information for the three study sites, Thessaloniki, Vienna and Messina that were addressed in SYNER-G. Fine scale information on exposed elements that for SYNER-G include buildings, civil engineering works and population, is one of the variables used to quantify risk. Collecting data and creating exposure inventories is a very time-demanding job and all possible data-gathering techniques should be used to address the data shortcoming problem. This report focuses on combining direct observation and remote sensing data for the development of exposure models for seismic risk assessment. In this report a summary of the methods for collecting, processing and archiving inventory datasets is provided in Chapter 2. Chapter 3 deals with the integration of different data sources for optimum inventory datasets, whilst Chapters 4, 5 and 6 provide some case studies where combinations between direct observation and remote sensing have been used. The cities of Vienna (Austria), Thessaloniki (Greece) and Messina (Italy) have been chosen to test the proposed approaches.JRC.G.5-European laboratory for structural assessmen

Towards a uniform earthquake risk model for Europe

Seismic risk has been the focus of a number of European projects in recent years, but there has never been a concerted effort amongst the research community to produce a uniform European risk model. The H2020 SERA project has a work package that is dedicated to that objective, with the aim being to produce an exposure model, a set of fragility/vulnerability functions, and socio-economic indicators in order to assess probabilistic seismic risk at a European scale. The partners of the project are working together with the wider seismic risk community through web tools, questionnaires, workshops, and meetings. All of the products of the project will be openly shared with the community on both the OpenQuake platform of the Global Earthquake Model (GEM) and the web platform of the European Facilities for Earthquake Hazard and Risk (EFEHR)

The European Seismic Risk Model 2020 (ESRM20)

This study describes the development of the various components of the European Seismic Risk Model 2020 (ESRM2020) which will be able to generate, using open-source software developed by the GEM Foundation (the Open Quake-engine), a number of Europe-wide risk metrics including average annualised human and economic losses (AAL), probable maximum losses (PML), and risk maps showing the losses for specific return periods or scenario events. The latest developments towards pan-European exposure models for residential and non-residential buildings and fragility/vulnerability models for damage, economic loss and casualty assessment will be presented. For engineered buildings within the exposure model (reinforced concrete, steel), a simulated design is undertaken using the key aspects of seismic design codes in force across Europe over the past 100 years. The designed MDOF building is then transformed to a SDOF model and nonlinear dynamic analyses are run using a large number of ground motion records, after which cloud analysis is used to develop the fragility functions. For non-engineered buildings (unreinforced masonry, confined masonry, adobe), the SDOF models have been directly developed from simplified formulae, experimental tests and previous studies. Collaboration from local experts at various stages of the model development, initiated through workshops, is an important component of the model, as well as the extensive calibration and validation

Tsunami risk communication and management: Contemporary gaps and challenges

Very large tsunamis are associated with low probabilities of occurrence. In many parts of the world, these events have usually occurred in a distant time in the past. As a result, there is low risk perception and a lack of collective memories, making tsunami risk communication both challenging and complex. Furthermore, immense challenges lie ahead as population and risk exposure continue to increase in coastal areas. Through the last decades, tsunamis have caught coastal populations off-guard, providing evidence of lack of preparedness. Recent tsunamis, such as the Indian Ocean Tsunami in 2004, 2011 Tohoku and 2018 Palu, have shaped the way tsunami risk is perceived and acted upon. Based on lessons learned from a selection of past tsunami events, this paper aims to review the existing body of knowledge and the current challenges in tsunami risk communication, and to identify the gaps in the tsunami risk management methodologies. The important lessons provided by the past events call for strengthening community resilience and improvement in risk-informed actions and policy measures. This paper shows that research efforts related to tsunami risk communication remain fragmented. The analysis of tsunami risk together with a thorough understanding of risk communication gaps and challenges is indispensable towards developing and deploying comprehensive disaster risk reduction measures. Moving from a broad and interdisciplinary perspective, the paper suggests that probabilistic hazard and risk assessments could potentially contribute towards better science communication and improved planning and implementation of risk mitigation measures

Investigation of the Rail-Induced Vibrations on a Masonry Historical Building

Increasingly historic masonry buildings are subjected to higher levels of traffic and rail vibrations due to urbanization and population growth. Deterioration and destabilisation of these buildings may result, especially if they were previously damaged (e.g. earthquakes or settlement problems). To better understand building response, vibration measurements were conducted on the Little Hagia Sophia Mosque, located adjacent to Istanbul’s Sirkeci-Halkali railway line. Transport-induced vibrations were recorded at several points on the ground and building. Attenuation characteristics in the ground and amplification features on the building were examined. Peak particle velocities often exceeded previously established thresholds for human perception and in some cases for structural damage. These are evaluated with respect to the building’s condition.Deposited by bulk impor

Earthquake performance assessment and rehabilitation of two historical unreinforced masonry buildings

The paper describes the earthquake performance assessment of two historical buildings located in Istanbul exposed to a Mw=7+ earthquake expected to hit the city and proposes solutions for their structural rehabilitation and/or strengthening. Both buildings are unreinforced clay brick masonry (URM) structures built in 1869 and 1885, respectively. The first building is a rectan-gular-shaped structure rising on four floors. The second one is L-shaped with one basement and three normal floors above ground. They survived the 1894, Ms=7.0 Istanbul Earthquake, during which widespread damage to URM buildings took place in the city. Earthquake ground motion to be used in performance assessment and retrofit design is determined through probabilistic and deterministic seismic hazard assessment. Strength characteristics of the brick walls are assessed on the basis of Schmidt hammer test results and information reported in the literature. Dynamic properties of the buildings (fundamental vibration periods) are measured via ambient vibration tests. The buildings are modelled and analyzed as three-dimensional assembly of finite elements. Following the preliminary assessment based on the equivalent earthquake loads method, the dynamic analysis procedure of FEMA 356 and ASCE 41-06 [2 and 8] is followed to obtain dynamic structural response of the buildings and to evaluate their earthquake performance. In order to improve earthquake resistance of the buildings, reinforced cement jacketing of the main load carrying walls and application of fiber reinforced polymer bands to the secondary walls are proposed.JRC.G.5-European laboratory for structural assessmen

ELER Software - a New Tool for Urban Earthquake Loss Assessment

Rapid loss estimation after potentially damaging earthquakes is critical for effective emergency response and public information. A methodology and software package, Earthquake Loss Estimation Routine-ELER, for rapid estimation of earthquake shaking and losses throughout the Euro-Mediterranean region (Erdik et al., 2008a and 2010a, Hancilar et al., 2009, Sesetyan et al., 2009) was developed under the Joint Research Activity-3 (JRA3) of the EC FP6 Project entitled ¿Network of Research Infrastructures for European Seismology- NERIES (www.neries-eu.org)¿. Recently, a new version (v2.0) of ELER software has been released. The multi-level methodology developed is capable of incorporating regional variability and uncertainty stemming from ground motion predictions, fault finiteness, site modifications, inventory of physical and social elements subjected to earthquake hazard and the associated vulnerability relationships. Although primarily intended for quasi real-time estimation of earthquake shaking and losses, the routine is also equally capable of incorporating scenario based earthquake loss assessments. This paper introduces the urban earthquake loss assessment module (Level 2) of ELER software. Spectral capacity based loss assessment methodology and its vital ingredients are presented. Analysis methods of Level 2 module are applied to the selected building types for validation and verification purposes. The damage estimates are compared to the results obtained from the other studies available in the literature, i.e. SELENA v4.0 (Molina et al., 2008) and ATC-55 (Yang, 2005). A loss assessment exercise for a scenario earthquake for the city of Istanbul is conducted and physical and social losses are presented. Damage to the urban environment is compared to the results obtained from similar software, i.e. KOERILoss (KOERI, 2002) and DBELA (Crowley et al., 2004).JRC.G.5-European laboratory for structural assessmen