UCLA Civil & Environmental Engineering Department
C&EE 200 Section 1 Seminar
Structural, Geotechnical and Civil Engineering Materials
“Simulated Ground Motions for Engineering Practice: Validation Accomplishments and Challenges”
Farzin Zareian
Associate Professor
University of California, Irvine
zareian@uci.edu | https://faculty.sites.uci.edu/pbee/

Abstract: Strong ground motion time series are required in many engineering applications, such as response history
analysis of structural or geotechnical systems. Simulated ground motions can be used to replace or supplement
real ground motions when recorded motions are scarce or nonexistent. Although the database of recorded
motions has increased by thousands during recent earthquakes, still there is a shortage of records for
large‐magnitude earthquakes at short distances, as well as records that sample specific combinations of
source, path, and site characteristics. Simulated ground motions have not been fully embraced by the engineering
community despite the fact that design codes such as ASCE/SEI allow the use of such motions in
engineering practice. The general concern among engineers is that even for moderate magnitude and distances,
simulated motions may not be equivalent to real motions when it comes to estimating seismic demand
for structural and geotechnical systems. To gain confidence in simulated ground motions, the Southern
California Earthquake Center (SCEC) has established a Technical Activity Group, dubbed as GMSV
(Ground Motion Simulation Validation), to develop and implement, via collaboration between ground motion
modelers and engineering users, testing/rating methodologies for simulated ground motions to be used
in engineering applications. The talk will summarize developments in validation of simulated ground motions
for engineering practice. Ground motion simulation validation for various applications will be presented,
along with a discussion of their limitations.

Bio: Dr. Zareian is an Associate Professor at the University of California Irvine where his
teaching and research interest is in Performance Based Earthquake Engineering
(PBEE). His research efforts have been focused on the development of new methodologies
for enhancement of PBEE, implementation of PBEE for assessment of specific
structure types, i.e. steel buildings and skewed bridges, validation of simulated
ground motions, and development of tools for implementation of PBEE by engineering
practice. His ongoing projects include development of guidelines for ground motion
modeling for performance‐based earthquake engineering of ordinary bridges, and validation and utilization
of physics‐based simulated ground motions for bridge performance assessment. Some of Dr. Zareian’s
recent projects have addressed validation of simulated ground motions for SDOF and building structures,
and characterization of seismic response of bridges with skewed abutments.