The following link will take you to the FHWA publication Geotechnical Engineering Circular No. 3 - Earthquake Engineering for Highways. It has discussion of seismic slope stability;
http://www.fhwa.dot.gov/engineering/geotech/library_arc.cfm?pub_number=19
I am faced with a unique foundation arrangement and would appreciate guidance on how to analyze:
Location: Wastewater treatment plant
Project: Adding two large egg-shaped digesters and associated piping galleries. Plan view looks like a giant pair of Elton John eyeglasses - two round lenses...
