American Society of Civil Engineers

Seismic Response of Transamerica Building. I: Data and Preliminary Analysis

by M. Çelebi, M.ASCE, (Res. Civ. Engr., U.S. Geological Survey, MS/977, 345 Middlefield Rd., Menlo Park, CA 94025) and E. S¸afak, M.ASCE, (Res. Struct. Engr., U.S. Geological Survey, MS-922, Reston, VA 22092)

Journal of Structural Engineering, Vol. 117, No. 8, August 1991, pp. 2389-2404, (doi:

     Access full text
     Permissions for Reuse  

Document type: Journal Paper
Abstract: The objective of this paper is to present preliminary analyses of a set of acceleration response records obtained during the October 17, 1989 Loma Prieta earthquake (Ms=7.1) from the 60-story vertically tapered, pyramid-shaped Transamerica Building—a landmark of San Francisco. The building was instrumented in 1985 with 22 channels of synchronized sensors consisting of 13 uniaxial accelerometers deployed throughout the structure and connected to a central recording system and three triaxial strong-motion accelerographs at three different levels of the structure. No free-field accelerographs are at the site. The acceleration records permit the study of the behavior of this unique structure. The predominant translational response of the building and the associated frequency at approximately 0.28 Hz are identified from the records and their Fourier amplitude spectra. The records do not indicate any significant torsional motion. However, there is rocking type soil-structure interaction, and an associated frequency of approximately 2.0 Hz is identified from the Fourier amplitude spectra of the differential motions between the ground level and that at the basement. In addition, the response spectra for the basement motions indicate significant resonance in both directions at a period of approximately 0.5 seconds.

ASCE Subject Headings:
Commercial buildings
High-rise buildings
Response spectra
Seismic effects
Soil-structure interactions