Performance-Based Seismic Design and Retrofitting via Drift and Strain Criteria

In recent decades, the demand for seismic code updates has significantly increased. Performance-based seismic design (PBSD) is a modern approach to earthquake-resistant building construction. By using this technique, the designers can establish performance targets that satisfy the owner. Most codes rely on strength design that utilizes a design response spectrum, highlighting serviceability without addressing performance levels. In this paper, an appraisal for the incorporation of PBSD into the Egyptian Code is proposed using nonlinear static and dynamic analysis. At first, response spectrum charts for 72, 475, and 2475 years return periods (RP) were developed based on the Egyptian seismicity information. Limits for different performance levels related to inter-story drift and strain values are then established. The proposed framework is applied to 6-story and 15-story RC buildings. The results demonstrated the importance of performing PBSD over relying solely on strength design. Seven earthquakes are used when performing nonlinear dynamic time-history analysis. Retrofitting using steel outriggers and steel bracings is applied to the building to improve its performance. Results indicated a proper estimate of performance using the proposed framework for both original and retrofitted buildings.