Report No: CCEER-90-2

Authors: Saber M. Abdel-Ghaffar, Emmanuel M. Maragakis, and Mehdi Saiidi

Date: July 1990

Sponsoring Agency: National Science Foundation

Performing Organization:

Department of Civil Engineering/258

University of Nevada, Reno

Reno, NV 89557

Abstract:

Strong motion records from several reinforced concrete structures were recovered after the 1987 Whittier, California earthquake. The purpose of this study was to review the available data from reinforced concrete buildings, to select representative buildings, and to analyze these buildings using available computer programs for linear analysis. Four buildings were selected for analysis. Linear-elastic, two and three dimensionals mathematical models were built for each structure based on the physical properties of the structural members. The response of these models to the Whittier Earthquake was evaluated using the linear analysis program IMAGES-3D. Comparison of the results of the computer analysis to the available data showed good agreement for the majority of the buildings studied.

The effects of the damping variation as well as the soil-structure interaction were considered in some buildings. It was noticed that the damping ratios which were calculated from the recorded earthquake responses of each structure gave the best correlation between the measured and the calculated responses. The assumption of the fixed supports was found to be reasonable, because the soil-structure interaction did not appear to have a major effect on the response of the buildings. Studies related to the hysteretic behavior of two buildings were performed and showed that the buildings responded essentially in the linear range (Abstract by authors).