UCLA Civil & Environmental Engineering Department
C&EE 200 Section 1 Seminar
Structural, Geotechnical and Civil Engineering Materials
2019 NAWS China Lake Earthquake Response & Recovery
David Swanson, P.E., S.E., F.SEI
Charles Liu, EIT
Reid Middleton, Inc.
Email: dswanson@reidmiddleton.com | cliu@reidmiddleton.com | www.reidmiddleton.com
On July 4th and 5th, 2019, two earthquakes (magnitudes 6.4 and 7.1, respectively) occurred with their
epicenters on the Naval Air Weapons Station China Lake (NAWSCL) in Ridgecrest, California. This
1.1 million acre weapons research site is about the size of the state of Rhode Island and has approximately
2,132 buildings and facilities, several hundred of which were significantly damaged during
the two earthquakes and subsequent aftershocks. The Naval Facilities Engineering Command Southwest
immediately engaged the Reid Middleton engineering team to perform detailed building safety
evaluations per the Applied Technology Council (ATC) standard, ATC-20 Procedures for Postearthquake
Safety Evaluation of Buildings of over 600 facilities scattered across the naval station. The first
three weeks of the earthquake response and recovery work expended over 6,700 engineering hours.
Partially collapsed roofs, distressed concrete columns, significant vertical offsets on the fault-lines
and design and rapid installation of emergency building shoring were among the engineering challenges
to overcome. An overview of the earthquake response and recovery engineering efforts at the
NAWSCL will be presented.
Where: Engineering VI-134A
When: 12:00 – 12:50 PM, Tuesday, January 28, 2020
David Swanson, P.E., S.E., F.SEI, Principal
Dave’s structural engineering expertise includes the design and seismic rehabilitation of buildings
for aviation, civic, commercial, educational, healthcare, and military projects throughout the western
United States and the Pacific Rim. Dave serves on the national Disaster Response & Recovery
Committee of the Infrastructure Resilience Division of ASCE and he is a Structural Engineer on
FEMA’s Urban Search & Rescue (US&R) Task Force and was recently deployed for the 2017 Hurricane
Irma response. He is a certified CalOES Safety Assessment Program (SAP) Instructor and
routinely provides SAP training for engineers throughout the United States. Throughout his 30 year career, Dave has
organized and led Disaster Reconnaissance Teams following the devastating earthquakes and tsunamis in Japan (1995),
Taiwan (1999), China (2008), Chile (2010), Haiti (2010), New Zealand (2011), Japan (2011), and most recently the 2017
M7.1 Central Mexico Earthquake. Dave is an Affiliate Professor in the Civil and Environmental Engineering Department
at the University of Washington. He has authored and published more than 25 technical papers on structural and earthquake-
resistant design and seismic risk reduction of buildings. Dave received his BSCE and MSCE from the University
of Washington.
Charles Liu, EIT, Designer
Charles is a structural design engineer at Reid Middleton who has experience with seismic analysis
and design, load rating evaluations, performance-based earthquake engineering, linear and nonlinear
dynamic structural analyses, and design of wood, masonry, concrete and steel structures. He has
spent over 350 hours in the earthquake response and recovery effort at NAWSCL, and has expertise
with structural and seismic retrofit projects across California that have involved nonlinear dynamic
and nonlinear static analyses. One of his larger scale projects currently involves a seismic analysis
and subsequent retrofit design of a 344,000 square foot mission critical essential facility. Charles Liu graduated from the
University of California, San Diego with his B.S. in Structural Engineering and from the University of California, Los
Angeles with his M.S. in Civil Engineering.