Effects of conditioning criteria for ground motion selection on the probabilistic seismic responses of reinforced concrete buildings

Abstract

Ground motion selection is arguably the most crucial step in performance‐based seismic design and risk assessment, as it bears the highest level of uncertainty that needs to be propagated through the calculations. The presently typical approach to capture this uncertainty in predicted structural responses is to use a suite of ground motions that match a uniform‐hazard response spectrum. This study examines the downstream effects of ground motion selection made through a variety of conditioning criteria based on one, two, or average of more‐than‐two intensity measures, and also with respect to different earthquake characteristics. Ductile and nonductile reinforced concrete moment frames with varying heights are used as model problems in detailed parametric studies. A risk‐based approach is adopted to develop a point‐of‐comparison reference demand. Seismic responses obtained using different ground motion suites compiled using three different conditioning criteria are then compared against this reference to determine the extent to which the selected ground motion suites can capture various critical structural responses.