Research on seismic resilience evaluation method of RC frame structures

The quantitative characterization of post-earthquake functional loss and dynamic recovery processes in RC frame structures is the cornerstone for evaluating their seismic resilience. In this paper, a quantitative model for assessing functional loss in RC frame structures is established, spanning from the component to the floor and the structural scale, by analyzing the hierarchical transmission mechanism of functional loss. Additionally, a simulation of the recovery process is conducted using time progression and benchmark algorithms to obtain a complete functional recovery curve. Based on this, an assessment method for the seismic resilience of RC frame structures is established, using functional loss, repair time, and repair rate as metrics. Subsequently, the RC frame structures with different numbers of floors and fortification intensities are built using OpenSees software. The influences of various parameters on the seismic resilience of RC frame structures are analyzed. The results show that as the seismic design intensity increases, both the functional loss and repair time of the structure continue to grow, while the repair rate remains approximately equal under large earthquakes and super earthquakes but relatively slow under moderate earthquakes. Under the same seismic design intensity, the functional loss and repair time of the 6-degree (0.05 g) and 7-degree (0.10 g) fortification structures are significantly lower than those of other fortification structures, while the functional loss and repair time of the 7-degree (0.15 g) fortification structure are the largest. The repair rates of structures across different fortification intensities remain approximately equal. As the number of floors increases, the repair time of the structure tends to rise, while the functional loss and repair rate tend to decrease. The research results can provide a reference for the seismic resilience evaluation of offshore urban systems and the realization of the national resilience urban-rural development goals.