Seismic fragility assessment of RC frame-shear wall structures designed according to the current Chinese seismic design code

Abstract

After learning from several devastating earthquakes in China in recent years, stricter design criteria have been introduced in the current Chinese seismic design code. To investigate the reliability of the current seismic design code, seismic fragility analyses were performed for 45 10-story reinforced concrete (RC) frame-shear wall structures designed according to the current Chinese seismic design code by analytical methods, considering the uncertainty of earthquake ground motions. The plastic rotation at the ends of the structural component (or the total chord rotation) and the maximum inter-story drift were employed as damage identifiers to quantify the four performance levels, i.e., fully operational, operational, repairable and collapse prevention. Thus, seismic fragility curves corresponding to individual performance levels were developed on the basis of nonlinear time history analyses for the reference RC frame-shear wall structure. The influences of the site soil type, the seismic protection intensity and the performance index on the fragility curves were analyzed. The structural reliability of RC frame-shear wall structures was examined using the developed fragility curves. The results indicate that the seismic performance objectives of RC frame-shear wall structures designed according to the current Chinese seismic design code can be achieved with good reliability.