Seismic vulnerability assessment of RC buildings with setback irregularity

Abstract

This study aims to perform a fragility analysis of RC buildings subjected to seismic loading. For this purpose, the curves of fragility are developed for 20 building models with different setback values. Using a finite element calculation program, nonlinear static analyses are performed. The outcomes indicate that the performance of building structures is highly affected due to the setback. Also, the seismic fragility is more pronounced when setback passes from level 1 to level 4. The fragility analysis shows that, for a setback value equal to 50%, the difference between the probability of damage, when the setback passes from the bottom of the structure to level 4, is 12.19%, 30.85%, 37.03%, and 41.16% for a slight, moderate, severe, and complete state of damage, respectively. Moreover, the structures with a setback on the fourth floor exhibit poor seismic performance, and therefore, a high probability of damage.

Keywords

• Seismic vulnerability
• RC buildings
• Setback irregularity
• Nonlinear static analysis
• Fragility curves