10:45 AM - 12:15 PM
[SCG53-P04] Investigation of site amplification correction for the real time prediction of ground motion for a whole area
Keywords:real time ground motion prediction, site amplification factors
Ground motion prediction scheme based on a monitoring of current wavefield (e.g., Hoshiba and Aoki, 2015) seems to be able to predict a detailed ground motion distribution, because the scheme can implicitly include complex source and path effects during the process of estimating current wavefield. In Hoshiba and Aoki (2015) and Ogiso et al. (2018), they first corrected a site amplification term in each seismogram using time-domain filters, then they used the seismograms in the scheme. As a result, the site amplification terms of the output predicted wavefield were common among stations. For a practical use of the predicted wavefield, we have to convolve site amplification terms that depend on target areas.
If we could use enough observed seismograms at each target area, we can estimate and use empirical site amplification factors for the purpose. However, it is impossible to use such empirical site amplification factors for the whole of target area. Hence, we should use site amplification factors based on the subsurface structure. In this presentation, we use site amplification factors that opened in the J-SHIS site operated by the NIED.
Calculation procedure is as follows: first, we correct a site amplification term of each seismogram using time domain filters. Then, we integrate them once and make mean square envelopes of ground velocity. We use such seismogram envelopes as the input of the prediction scheme. After calculation, we correct site amplification terms of predicted wavefield using amplification factors at the reference station and target areas. In this presentation, we will present some examples of predictions.
If we could use enough observed seismograms at each target area, we can estimate and use empirical site amplification factors for the purpose. However, it is impossible to use such empirical site amplification factors for the whole of target area. Hence, we should use site amplification factors based on the subsurface structure. In this presentation, we use site amplification factors that opened in the J-SHIS site operated by the NIED.
Calculation procedure is as follows: first, we correct a site amplification term of each seismogram using time domain filters. Then, we integrate them once and make mean square envelopes of ground velocity. We use such seismogram envelopes as the input of the prediction scheme. After calculation, we correct site amplification terms of predicted wavefield using amplification factors at the reference station and target areas. In this presentation, we will present some examples of predictions.