Some new research on the Newmark Displacement Method for earthquake-induced landslides indicates that the method may be on the unconservative side. The Landslide Blog provides a short summary of the paper by Li et al. (2018) that was recently published in the journal Landslides. Their research was based on physical models on a shake table, comparing the results of the model experiments with a Newmark analysis. The paper should be worth a read for geotechnical engineers practicing in seismically active areas. It sounds like some additional study is needed to confirm these results and if they are true, propose different ways of analyzing earthquake-induced landslides.
From the USGS Newsroom:
USGS scientist Ken Hudnut fills us in on how science created the theoretical magnitude 7.8 earthquake behind the Great Southern California ShakeOut—the largest earthquake preparedness drill in U.S. history, coming Nov. 13—and what such an earthquake would do to downtown Los Angeles.
Seems like they did it right wiith this study. They had multiple teams independenlty come up with the ground shaking model, then had different structural engineers who are experts in seismic design of large buildings review the tall buildings in the L.A. area for the design earthquake. They say that buildings would likely come down in the 7.8 magnitude event. Click through to watch the video interview from the USGS.