SCEC Award Number 25052 View PDF
Proposal Category Individual Research Project (Single Investigator / Institution)
Proposal Title Feature Enhancements to the Broadband Platform: Site Response Modules and Ground Motion Models
Investigator(s)
Name Organization
Chukwuebuka Nweke University of Southern California
SCEC Milestones A2-1, C1,2,3-1 SCEC Groups RC, GM, CEM
Report Due Date 03/15/2026 Date Report Submitted 05/06/2026
Project Abstract
 The proposed project aims to enhance the Broadband Platform (BBP) by focusing on improvements to the Site Response (SR) and utility modules. Specifically, the objective is to:
1.Improve the accuracy of the SR module by integrating site-specific Z1.0 values and expanding the functionality of PySeismoSoil to support low-frequency seismograms.
2.Integrate the Bayless and Abrahamson (Bayless and Abrahamson 2019) frequency-based site response analysis method.
3.Update the utility modules by incorporating the latest BSSA14 GMM, including the Southern California basin model, and adding an EAS-based GMM (Bayless and Abrahamson 2019) for enhanced comparison capabilities.
Intellectual Merit The modules provided to the BBP platform as part of this work advances the toolset available to researchers from various backgrounds (engineering, seismology, etc) to perform cutting edge analysis that will further the science goals of SCEC and the entire field at large (ground motion hazard, computing, subsurface modeling).
Broader Impacts This updated modules will serve the broader research community through the provisions of tools that allow for analysis that includes current state of practice/art procedures and methods. This includes updates site adjusted methods for reference broadband simulations (where adjustments can be made using an increased number of measured (inferred)site parameters).
Project Participants This work was conducted/implemented by Sajan KC under my guidance. We thanks Fabio Silva and Phil Maechling of SCEC for their support and help to enact the implementations.
Exemplary Figure Figure 1. Screenshot of the GitHub Pull Request (#63) submitted to the SCEC BBP development team proposing an extended 10-column station file (.stl) format with backward compatibility, adding support for z1.0, basin_id, and basin_label fields required for the updated site response modules and BSSA14 GMM with Southern California Basin Model.
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