Performance‐based damage assessment of low‐rise reinforced concrete buildings

Abstract

For any places located in zones with high seismic risk, seismic damage assessment of buildings is a crucial issue. In the past few years, much attention has been paid to the concept of performance‐based assessment due to ATC‐40. However, its tedious procedure and deficiency in precision have left room for improvement. In the present paper, a modified procedure is introduced. It is expected to improve the efficiency as well as accuracy of the assessment. The main idea of the modification is to treat the performance points on the structural capacity curve as input, and subsequently determine the corresponding seismic demands of RC structures. The proposed approach is also capable of finding the correlations between peak ground acceleration (PGA) and various structural performances. On the other hand, it is well known that the accuracy of pushover analysis is greatly affected by the proper setting of the plastic hinges. Here, an algorithm for determining plastic hinges with respect to three well‐known distinct failure modes is also suggested. To further testify to the adequacy of the new approach, a practical low‐rise traditional RC school building damaged in the Chi‐Chi earthquake is adopted as a case study. Following the proposed seismic damage assessment procedures, a pushover analysis based on the suggested algorithm is performed to find the ultimate PGA that the building could sustain. The accuracy of the results is then verified by applying the nonlinear time history analysis. It is seen that the proposed method gives acceptable results and is expected to be helpful both in facilitating seismic damage assessment, as well as in formulating strategies for repairing, retrofitting, or strengthening for RC buildings.