United States building code approach to variations in regional seismicity

  • Charles A. Kircher Kircher & Associates, Mountain View, USA


The United States contains regions of greatly varying seismicity ranging from a relatively narrow strip of very high seismicity along coastal California in the West to broad areas of low or moderate seismicity typical of the Central and Eastern United States. The United States currently has three major regional model building codes. While all three codes have traditionally used the concept of seismic zones to identify and distinguish between regions of different seismicity, they have not had a consistent basis for their seismic criteria. Beginning in the year 2000, the three model building codes will merge and become the new International Building Code (IBC) applicable to the whole United States. New seismic design criteria have been developed for the 2000 IBC that now define ground shaking for building design by spectral acceleration contours. This paper describes the background and basis for the new seismic design criteria of the 2000 IBC, and how these criteria address the large variation in seismic hazard across the United States.


Algermissen, S.T. 1983. An Introduction to the Seismicity of the United States,. (Oakland, CA: Earthquake Engineering Research Institute).

American Society of Civil Engineers. 1996. Minimum Design Loads for Buildings and Other Structures. ASCE 7-95. (Washington, D.C.: ASCE).

Buildings Officials and Code Administrators International 1997. The BOCA National Building Code. (Country Club Hills, IL:BOCA).

Federal Emergency Management Agency. 1995. NEHRP Recommended Provisions for Seismic Regulations for New Buildings. (Washington, D.C.: FEMA 222/223).

Federal Emergency Management Agency. 1998. NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures. (Washington, D.C.:FEMA-302/30).

Frankel, Arthur et al. 1996. "National Seismic-Hazard Maps: Documentation June 1996". Open-File Report 96-532. (Denver, CO: U.S. Geological Survey). DOI: https://doi.org/10.3133/ofr96532

International Code Council. 1998. International Building Code (Final Draft), (Birmingham, AL:ICC).

International Conference of Building Officials. 1997. 1997 Uniform Building Code. (Whittier, CA:ICBO).

Kircher, Charles A. 1998. "New Ground Shaking Design Criteria." Structural Engineering World Wide 1998, Structural Engineers World Congress, July 18-23, 998, San Francisco, CA (New York, NY:Elsevier).

Seismology Committee of the Structural Engineers Association of California. 1996. Recommended Lateral Force Requirements and Commentary. (Sacramento, CA:SEAOC).

Southern Building Code Congress International, 1997. Standard Building Code. (Birmingham, AL:SBCCI).

How to Cite
Kircher, C. A. (2000). United States building code approach to variations in regional seismicity . Bulletin of the New Zealand Society for Earthquake Engineering, 33(1), 48-55. https://doi.org/10.5459/bnzsee.33.1.48-55