
Seismic Design of Liquid Storage Tanks
Course Summary
In recent years, significant advances have occurred in linear and nonlinear dynamic analyses of tank-liquid-foundation systems. Advances have also occurred in site-specific estimates of ground motion parameters. Modern seismic analyses are based on probabilistic response spectrum rather than deterministic peak ground acceleration. This seminar will present a step-by-step discussion of advances in ground motion estimates and dynamic response analyses.
» Seattle, WA, Aug 14, 2009
Price
» Members: $685
» Non Members: $795
Instructors
Praveen K. Malhotra, Ph.D., P.E., M.ASCE,
Dr. Malhotra is a Senior
Research Specialist with FM Global in
Norwood, MA. He has published
extensively on seismic response of tanks. He is the current chair of the ACI 376
task group for seismic design of LNG tanks. He has actively participated in
updating the tank design provisions in NEHRP, Eurocode and Indian Standard. Dr.
Malhotra received his Ph.D. in structural/geotechnical earthquake engineering
from Rice University. He is a member of the American Concrete Institute (ACI),
Earthquake Engineering Research Institute (EERI), Seismological Society of
America (SSA), and the Indian Society of Earthquake Technology (ISET). He is a
registered Civil Engineer in California.
Course Description
Under gravity loads, upright cylindrical tanks are highly efficient
structural systems for storing liquids such as drinking water, sprinkler water,
crude oil, LNG, wines and juices. Under earthquake loads, a complicated pattern
of stresses is generated in the tanks. Poorly designed tanks have leaked,
buckled or even collapsed during earthquakes. Common modes of failure are wall
buckling, sloshing damage to roof, inlet/outlet pipe breaks and implosion due to
rapid loss of contents.
In recent years, significant advances have
occurred in linear and nonlinear dynamic analyses of tank-liquid-foundation
system. Significant advances have also occurred in site-specific estimates of
ground motion parameters. Modern seismic analyses are based on probabilistic
response spectrum rather than deterministic peak ground acceleration. This
seminar will present a step-by-step discussion of advances in ground motion
estimates and dynamic response analyses.
Seminar Benefits
- Gain an understanding of the dynamic response of tanks
- Learn to obtain site-specific response spectra for tanks
- Learn rules to avoid common modes of failure in tanks
- Learn about the shortcomings of current design provisions
- Learn changes to the seismic design provisions in
AWWA
D 100, API 650 and ACI 376 - Learn about nonlinear analysis of tanks
- Learn about base isolation and energy dissipation techniques to improve seismic performance of tanks
Who Should Attend
Structural and geotechnical engineers, planners, risk managers and
manufacturers interested in design and performance assessment of tanks for
various applications.
Summary Outline
8:00 AM to 9:45 AM
- 8:00 AM to 9:45 AM
Introduction
Model of tank-liquid system
Impulsive, convective and ‘breathing’ modes of vibration
Ground-supported and elevated tanks
10:00 AM to 12:00 Noon
Design Response Spectrum
Definition of response spectrum
Response spectrum from ASCE 7-02
Spectrum from site-specific analysis
Displacement-sensitive region of response spectrum
Spectrum of vertical motion
Damping adjustment of response spectrum
1 PM to 2:45 PM
Seismic Response of Tanks
Moments, base shear, axial and hoop stresses in tank wall
Sloshing at free-surface
Freeboard requirement
Roof loads in tanks with insufficient freeboard
3 PM to 5 PM
Special Topics
Soil-structure interaction analysis
Nonlinear static (pushover) analysis of tanks
Base isolation
Seismic energy dissipation