Seismic vulnerability study incorporating ambient vibration-based dynamic characterization : case of a reinforced concrete tower

Abstract

This end-of-study project assesses the seismic vulnerability of a 70-metertall reinforced concrete tower located in El Mohammadia, Algiers, used by the Ministry of Trade and Export Promotion. Situated in a high seismicity region, the tower’s ability to withstand earthquakes is critically important. The study involves evaluating the tower’s dynamic properties through ambient vibration analysis, developing and calibrating a finite element model in ETABS, and conducting seismic vulnerability assessments using both linear and nonlinear methods per the Algerian Seismic Regulations (RPA 99/2003) and the European Macroseismic Scale (EMS-98). Ambient vibration data was collected and analyzed to determine natural frequencies, mode shapes, and damping ratios. This data informed the calibration of the numerical model, which accurately represented the observed dynamic behavior. Seismic assessments, including pushover analysis, revealed that the tower meets the required performance criteria, with calculated and minimal reinforcements passing the RPA’s acceptance thresholds. The EMS-98 assessment indicated a reasonable damage degree, validating the tower’s resilience. This study highlights the importance of model calibration for accurate seismic assessment and suggests enhancements to RPA for more detailed performance evaluation, ensuring the tower’s structural integrity and seismic resilience.