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This article describes the Engineering Strong-Motion Database (ESM), developed in the framework of the European project Network of European Research Infrastructures for Earthquake Risk Assessment and Mitigation (NERA, see Data and Resources). ESM is specifically designed to provide end users only with quality-checked, uniformly processed strong-motion data and relevant parameters and has done so since 1969 in the Euro-Mediterranean region. The database was designed for a large variety of stakeholders (expert seismologists, earthquake engineers, students, and professionals) with a user-friendly and straightforward web interface. Users can access earthquake and station information and download waveforms of events with magnitude ≥ 4:0 (unprocessed and processed acceleration, velocity, and displacement, and acceleration and displacement response spectra at 5% damping). Specific tools are also available to users to process strong-motion data and select ground-motion suites for codebased seismic structural analyses.

The purpose of the work is to provide an experimental benchmark on the seismic behavior of tunnels, with the final aim of calibrating numerical and analytical design methods. A series of plane-strain centrifuge tests with dynamic loading on a model tunnel was, therefore, carried out at the Schofield Centre of the Cambridge University Engineering Department (CUED). Four samples of dry uniform fine sand were prepared at two different densities, in which an aluminum-alloy tube was installed at two different depths. The tube was instrumented with strain gauges to measure hoop forces and bending moments at significant locations. To monitor the amplification of ground motion from the base to the surface, vertical arrays of accelerometers were placed in the soil model and along the box. The instrumentation also included linear variable differential transformers (LVDTs) that measured the soil surface settlement during all test phases. The test procedure and the results are described in this paper, showing the evolution of both accelerations and internal forces along the tunnel lining during the model earthquakes.

This work describes a procedure to configure U.S. Geological Survey (USGS)‐ShakeMap for a given region. The procedure is applied to Italy to update and improve the ShakeMap service provided by Istituto Nazionale di Geofisica e Vulcanologia (INGV). The new configuration features (1) the adoption of recently developed ground‐motion models (GMMs) and of an updated map of VS30 for the local site effects and (2) the adoption of the newly developed USGS‐ShakeMap version 4 (v.4) software (see Data and Resources). We have used the same subdivision in tectonic regimes adopted for the GMMs for the new Italian seismic hazard model (MPS19, Meletti et al., 2017) and selected the most appropriate GMMs after application of a ranking procedure consisting of statistical tests. A cross‐validation technique has been applied to test the goodness of the selected configuration and to compare the ShakeMaps obtained with the old (Michelini et al., 2008) and the new settings. Finally, the INGV ShakeMap workflow has been renovated to exploit the data and analysis chain implemented at INGV from real‐time data streams acquisition to analyst revised waveforms including additional data (e.g., revised location, fault geometry) that may become available days after the event occurrence.