The effect of far and near field earthquakes on the collapse capacity of performance base optimization RC moment frames
ashkan khodabandehlou
1
(
civil
)
siamak saboonchi
2
(
Department of Civil Engineering, Urmia branch, Islamic Azad University, Urmia, Iran
)
Keywords: Incremental dynamic analysis, RC moment frame, center of mass meta-heuristic algorithm, performance base optimization,
Abstract :
Performance-based design is a new approach to the topics of seismic design of structures, which is based on changing the location of the structure, unlike the traditional methods of force-based design. The use of this approach in the process of structures design leads to the achievement of structures with proper performance and an acceptable level of reliability. The main goal of this research is to investigate the impact of near and far field earthquakes on the collapse capacity and fragility of performance base optimization RC moment frames using the center of mass meta-heuristic algorithm. Push over analysis has been used in the optimization process to control the responses of the studied frames at performance levels and incremental dynamic analysis has been used to evaluate the fragility of the obtained optimal frames. According to the obtained results for the collapse margin ratio and the adjusted collapse margin ratio for the 3, 6, and 12-story frames, we can see that the collapse margin ratio and therefore the seismic safety under far field earthquakes 7%, 16% and 8%, higher than from collapse margin ratio and seismic safety under near field earthquakes respectively. In other words, the optimal frames in this study against near-field earthquakes have low seismic safety and more fragility than far field earthquakes.