Effect of Infill Masonry Walls on the Seismic Response of Reinforced Concrete Buildings Subjected to the 2003 Bam Earthquake Strong Motion : A Case Study of Bam Telephone Center

Abstract

The Bam telephone center building, with a nonsymmetrical reinforced concrete momentresisting frame structure, is located about 1.5km northeast of the 2003 Bam earthquake strong motion station. Based on post-earthquake damage assessment results, almost no residual deformations or cracks were observed in the structural elements of the building. However, assuming the designed base shear coeffcient of the structure, nonlinear responses were expected due to the earthquake. Hence, to obtain an analytical answer for the almost linear performance of the building, 3-dimensional nonlinear time history analyses were carried out for north-south and east-west recorded strong motions. The response simulations were performed for different categories of bare frame and infilled frame. An approach was developed to model masonry infill walls with or without openings. The results of the analyses were compared to damage and residual cracks observed on the masonry infill walls. Reasonable correlations were obtained between analytical and observed results. It may be concluded that the presence of masonry infill walls is the main reason for the nearly linear responses of the Bam telephone center building during the earthquake