NGL, GMDB, and VsPDB Database Exploration Workshop

In recent years, several databases have been developed to advance geotechnical earthquake engineering by providing access to key data for a broad community including researchers, government agencies, and industry professionals. These include open-access relational databases such as the Next Generation Liquefaction (NGL) database, the Ground Motion database (GMDB), and the Shear-wave Velocity (Vs) Profile Database (VsPDB). In this pre-conference workshop (before Geocongress 2026), attendees will learn about the development of these databases, methods to access relevant data, and potential future benefits of using these resources.

The NGL project is advancing the state of the art in liquefaction research. One of its key products is a database of liquefaction case histories (https://nextgenerationliquefaction.org, https://doi.org/10.21222/C2J040). These case histories are collections of observations of ground failure (or lack thereof), geotechnical data (e.g., cone penetrometer test, standard penetration test), and estimates of ground motion intensity measures (e.g., peak ground acceleration, spectral acceleration). The web interface allows users to view, upload, and download data. Case history data are carefully reviewed by at least two experts to ensure quality, accuracy, and completeness. The NGL database continues to grow as new case histories are developed and new data are gathered. NGL teams use the data in the NGL database in focused topical studies and to develop predictive models for liquefaction initiation and its consequences.

The VsPDB (https://vspdb.org) contains VS profile data for sites in the United States. The VsPDB was developed and is maintained through a major multi-institutional effort. The data were collected from diverse sources such as private consulting engineering reports, university research reports, federal reports, California state agency documents, and reports provided by electric utilities. All data are within the public domain, but previously were difficult to access for most potential users. The broad and flexible relational database was developed to accommodate VS data sources from a wide array of geophysical techniques, presented in many different formats, and accompanied by widely divergent supplementary data, including P-wave velocities, geotechnical logs and other data, and penetration test data. The web interface facilitates data query, visualization, and download. This resource is anticipated to be useful to geotechnical engineers and engineering seismologists for diverse applications in research and industry practice.

The GMDB (https://gmdatabase.org/) contains earthquake ground motion metadata and intensity measures. The GMDB contains data from earthquake events in the Next Generation Attenuation (NGA)-East and NGA-West2 projects and many additional events collected since the completion of the NGA-West2 data collection efforts in 2011. The GMDB was designed to also accommodate the various fields included in NGA-Sub. This resource provides crucial data to researchers as they develop GMMs and to practicing engineers as part of site-specific hazard characterization studies.