Needs for Performance Codes
methods described in the previous pages (FEMA 273, SAC, etc.) are currently
being used on an ad hoc basis for important new and existing buildings.
These documents are only the first steps in developing Performance Based
Codes. Much work is needed to evaluate and validate the methodologies
that have been developed. Also, improved tools are needed for analysis
and design, and more tests are needed to quantify various performance
the focus has been only on structural performance. In general, economic
issues must be considered as well. Initial costs need to be compared with
"life cycle" costs to determine the design that performs best.
Economic costs also depend on who pays for the damage - the owner, insurance,
or the government.
consistent reliability oriented computer-assisted design methodology
is needed, but this may be too complex for routine design. However,
it would be useful for developing or calibrating simpler code methods
and for complex and important projects.
buildings are not typically rehabilitated to the same level of reliability
as new structures. However, whether this is good public policy, and
the manner in which this is treated, needs investigation.
impacts of having many buildings damaged need to be considered in developing
seismic codes. An earthquake is like an airplane crash -- both get more
attention and have greater impact than individual distributed auto accidents
or house fires.
of these issues are addressed in the EERC/FEMA action plan for performance
for Performance Based Design Codes
R. O., Performance Based Analysis and Design Procedure for Moment
Resisting Steel Frames, Background Document, SAC Steel Project,
September 10, 1998.
- Federal Emergency Management
Agency, NEHRP Guidelines for the Seismic Rehabilitation of Buildings
(FEMA Publication 273), Washington DC, 1997.
- Earthquake Engineering Research
Center, Performance-based Seismic Design of Buildings: An Action
Plan, U.C. Berkeley, 1995.
- International Conference of Building
Officials (ICBO), Uniform Building Code, Whittier, CA, 1994,
Engineers Association of California, Vision 2000 - A Framework for
Performance-based Design, California Office of Emergency Services,
Engineers Association of California, Recommended Lateral Force Requirements
and Commentary, Seismology Committee, San Francisco, April 1996.
Department of Defense, Design Guidelines for Essential Buildings,
Army TM 5-809-10-1, Navy NAVFAC P-355-1, Air Force ARM 99-3, Chapter
13, Section A, Washington, DC, 1986.