Incremental dynamic collapse analysis of RC core-wall tall buildings considering spatial seismic response distributions

Despite wide-ranging studies on fragility analysis and collapse safety assessment of short to medium-rise reinforced concrete (RC) structures, a new interest in the topic is still valuable and even necessary for tall RC buildings. This study aims at establishing fragility relationships as well as collapse probability of high-rise RC core-wall buildings under maximum considered earthquake ground motions. This study is carried out in a probabilistic framework on a case study of a fully 3dimensional numerical model developed to simulate seismic behavior of a 42-story building having a RC core-wall system. Proposing planar and vertical distributions of ductility and damage indices, the incremental dynamic analysis, and the multi-direction nonlinear static (pushover) analyses were employed to reach the research goal. Median collapse-level capacities were defined in terms of seismic responses (e.g., ductility/damage indices) as well as several intensity measures by employing statistical analyses and cumulative density functions. Available and acceptable collapse margin ratios were next estimated to quantify collapse safety at maximum considered earthquake shaking level. On an average basis, the statistics indicated 9%-10% and 5%-6% collapse probability of the building subjected to near-and far-field ground motions, respectively.