An NGA Model for the Average Horizontal Component of Peak Ground Motion and Response Spectra

We present a model for estimating horizontal ground motion amplitudes caused by shallow crustal earthquakes occurring in active tectonic environments. The model provides predictive relationships for the orientation‐independent average horizontal component of ground motions. Relationships are provided for peak acceleration, peak velocity, and 5‐percent damped pseudo‐spectral acceleration for spectral periods of 0.01 to 10 seconds. The model represents an update of the relationships developed by Sadigh et. al. (1997) and incorporates improved magnitude and distance scaling forms as well as hanging‐wall effects. Site effects are represented by smooth functions of average shear wave velocity of the upper 30 m ( V…