New PEER Report Published: 2014/17 “PEER NGA-East Database”

PEER has just published Report No. 2014/17 titled “PEER NGA-East Database” as a new addition to the PEER Report Series. It was authored by Christine A. Goulet, Tadahiro Kishida, Timothy D. Ancheta, Chris H. Cramer, Robert B. Darragh, Walter J. Silva, Youssef M.A. Hashash, Joseph Harmon, Jonathan P. Stewart, Katie E. Wooddell, and Robert R. Youngs.

Visit the PEER publications page to download a free color pdf of the document.

This report serves as a documentation of the ground motion database development for the NGA-East Project. The ground motion database includes the two- and three-component ground-motion recordings from numerous selected events (M > 2.5, distances up to 1500 km) recorded in the Central and Eastern North America (CENA) region since 1988. The final database contains over 29,000 records from 81 earthquake events and 1379 recording stations. The time series and metadata collected went through numerous rounds of quality assurance and review. The NGA-East database constitutes the largest database of processed recorded ground motions in Stable Continental Regions (SRCs).

The motivation behind the development of the empirical database is the same as for other NGA projects (NGA-West1 and NGA-West2), which is to be used, along with other information and data, for the development of ground motion prediction equations (GMPEs). The NGA-East ground motion database, similar to those from the NGA-West projects, includes pseudo-spectral acceleration (PSA) for the 5% damped elastic oscillators with periods ranging from 0.01 to 10 sec. The preferred PSA measure used for the NGA-East GMPE development is RotD50, which is also provided for the same period range. Additionally, the NGA-East database includes Fourier amplitude spectral (FAS) of the processed ground motions. The NGA-East database therefore consists of three groups of complementary products: the summary file referred to as the flatfile, which contains metadata, ground motion information and intensity measures on a record-per-record basis, the time series (acceleration, velocity, and displacement), and the corresponding Fourier spectra files.

The primary objective of the database task was to provide the time series, response spectra, and Fourier spectra to the NGA-East GMPE developers. However, the NGA-East time series database will also be made available to the public through the PEER online ground motion tool. This report documents the data collection, processing, and development of data products for the NGA-East database.