The Earthquake Engineering Online Archive

Simplified earthquake analysis of buildings including site effects

Hart, James D.; Wilson, Edward L.

UCB/SEMM-1989/23, Dept. of Civil Engineering, University of California, Berkeley, 1989-12, 202 pages (500/C23/89/23)

The use of simple methods is investigated for the earthquake analysis of buildings founded on soft soil sites. The topic of site response analysis is addressed including the development and implementation of efficient time domain numerical procedures which are incorporated into a one-dimensional site response analysis computer program, WAVES. A soft clay site in downtown Mexico City is modeled and analyzed with WAVES for various base input records and the computed results are compared to data recorded during the September 1985 earthquake. A study comparing the analytical response of a multidegree-of-freedom representation of a two-dimensional frame system with that of an equivalent single degree-of-freedom representation for harmonic earthquake loading is presented and the extension of single degree-of-freedom analysis to general two- and three-dimensional systems is discussed. A brief discussion of various soil-structure interaction analysis methods is followed by a presentation of the free-field formulation of the equations of motion for soil-structure systems. Simplified procedures which include the effects of site amplification and foundation flexibility are suggested and applied in the investigation of a simple soil-structure system.

Available online: http://nisee.berkeley.edu/documents/SEMM/SEMM-89-23.pdf (12 MB)