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On-site structure-specific real-time risk assessment: perspectives from the REAKT project

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Abstract

The availability of computationally powerful and energy-efficient wireless sensing units or WSUs (one or more arranged in the form of a network in the vicinity and/or within a structure of interest) has led to new developments in the field of building and seismic strong motion monitoring. These WSUs can serve several functions. Those of largest earthquake engineering and engineering seismology interest are the recording of ground shaking the building is subjected to, as well as its response, and the capability of running rapid seismic risk analyses on the basis of vulnerability models of the structure, possibly coupled with recorded data. The REAKT project has shed light on a number of prospective applications of the last generation of monitoring devices for seismic risk management of critical structures. These applications refer to real-time and near-real-time risk assessment, that is: earthquake early warning, immediate post-event response evaluations based on recorded shaking, and short-term aftershock risk management for automated building tagging. This paper summarizes these perspectives that, despite still presenting some challenges that may limit readiness to date, have potential for scientific innovation in the field.

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Notes

  1. In the case of non-linear structural response, ground motion recording at the site of the building may be used as an input to a non-linear model to gather information on the inelastic response (see the Sect. 3.3).

  2. In fact, it has been shown that if at a given time t from the earthquake’s origin, the seismic network can provide a vector of measures that are informative about the magnitude, then \(f_{M} \left( {m|\tau_{1} ,\tau_{2} , \ldots ,\tau_{n} } \right)\) may be obtained in an analytical form via the Bayes’ theorem. Likewise, because of rapid earthquake localization procedures, a probabilistic estimate of the epicenter may be available based on the sequence at which the stations trigger.

  3. The referenced studies consider the general case of vector-valued EDP and IM, as well the PDF of a damage measure given EDP (Eq. 3). It is easy to recognize that the representation given herein for the expected loss is equivalent. Note also that there are some conditional independency assumptions in the integrals of the equations; the interested reader is referred to the given references for details.

  4. The system declares an event (M larger than 3) only if at least three stations trigger within the same 2 s time interval.

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Acknowledgments

This study was partially developed within the Strategies and tools for Real-Time Earthquake Risk Reduction project (REAKT; http://www.reaktproject.eu), funded by the European Commission via the FP7 programme (Grant No. 282862). Partial support was also provided by the ISLAR project (https://www.axa-research.org/project/iunio-iervolino) granted by the AXA Research Fund in 2011 and the work benefitted from the collaboration with AMRA, Analisi e Monitoraggio dei Rischi Ambientali (http://www.amracenter.com). The installations in Thessaloniki were performed as collaboration between the Helmholtz Centre Potsdam–GFZ and the Department of Civil Engineering of the Aristotle University, in the framework of the REAKT work package “Strategic Applications and Capacity Building”. The authors thank B Petrovic, M Pittore, T Boxberger, C Milkereit for useful discussions and K Fleming for helping us in the preparation of the manuscript. Finally, the comments by an anonymous reviewer, Prof. Sinan Akkar, and the guest Editors are gratefully acknowledged.

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  1. Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Helmholtzstraße 7, 14467, Potsdam, Germany

    D. Bindi & S. Parolai

  2. Dipartimento di Strutture per l’Ingegneria e l’Architettura, Universitá degli studi di Napoli Federico II, via Claudio 21, 80125, Naples, Italy

    I. Iervolino

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Bindi, D., Iervolino, I. & Parolai, S. On-site structure-specific real-time risk assessment: perspectives from the REAKT project. Bull Earthquake Eng 14, 2471–2493 (2016). https://doi.org/10.1007/s10518-016-9889-4

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