BB-SPEEDset is a dataset of of near-source broadband earthquake ground motions from 3D physics-based numerical simulations obtained by the computer code SPEED.
BB-SPEEDset has been constructed by assembling a large set of waveforms simulated by SPEED, in most cases validated against earthquake recordings, and post-processed with an effective workflow apt to generate broadband accelerograms. The generation of broadband time histories starting from low-frequency SPEED results makes uses of a technique based on Artificial Neural Networks – ANN2BB (Paolucci et al. 2018), trained on strong motion records.
It has been proved that BB-SPEEDset provides a description of near-source ground motion consistent with earthquake recordings in similar magnitude and distance ranges in terms of:
- statistical distribution of peak and integral intensity measures
- ratios of long-to-short period spectral ordinates
- ground motion attenuation with distance
- directionality and impulsive features.
Example of peak ground motion maps (left: PGA; center: PGV; right: PGD) and selected broadband waveforms from BB-SPEEDset: L’Aquila April 6, 2009 earthquake (Mw 6.2).
Overview of BB-SPEEDset
The BB-SPEEDset, introduced in Paolucci et al. (2021), is being under continuous development, as more processed numerical simulations become available. The dataset is currently in its 2.3 version, including a total of 20’046 three-component waveforms from earthquake scenarios with MW from 4.9 to 7.4 and Joyner-Boore distances (Rjb) up to 110 km. Strike-slip, normal and thrust events are included in the dataset. Concerning soil classes, the majority of the waveforms (about 76%) is on stiff soil with VS30 > 600 m/s; some waveforms (nearly 1%) are on very soft soil with VS30 less than 200 m/s.
BB-SPEEDset distribution with respect to MW , Rjb and VS30
Citation
When used, BB-SPEEDset shall be cited as follows:
Download
BB-SPEEDset (v.2.3 released February 27th, 2024) is distributed as two separate zip files:
- BB-SPEEDset_v2.3_flatfile: flatfile (in both xlsx and mat format) including the metadata regarding the source, source-to-site distances, site response proxies, post-processing method and a large portfolio of ground motion intensity measures, from the standard peak and spectral measures to integral ones (e.g. duration, Arias Intensity, etc..), up to parameters related to impulsive ground motions (i.e. pulse period) and long period components of ground motions (i.e. fling step)
- BB-SPEEDset_v2.3_accelerograms: complete set of simulated broadband accelerograms corresponding to the flatfile.
Fundings
This work has been partially supported by Swissnuclear within the research activity “Development of advanced numerical approaches for earthquake ground motion prediction”, in the framework of the Sigma2 project, and by the Department of Civil Protection within the ReLUIS project WP18 “Normative contributions related to seismic action”.