Effect of Ground Motion Duration on Reinforced Concrete Shear Wall Buildings

Abstract

This paper investigates the effect of earthquake ground motion duration on the design and collapse risk of reinforced concrete shear wall buildings from 6 to 30 stories. Both design and collapse levels of shaking were considered through nonlinear incremental dynamic analysis. At the design level of shaking, it was found that (1) maximum interstory drifts were increased as ground motion duration increased (from <20 s to 35–150 s of strong shaking), though not enough to flag the designs as unacceptable; (2) story forces and moments were not significantly affected; and (3) energy demands were greatly increased by motion duration. When the records were scaled until collapse level, it was found that (1) the median collapse scaling level was greatly impacted by duration, and the median collapse shaking level was almost 20% higher on average when considering shorter records; and (2) long duration records produced both larger probabilities of collapse at the design shaking level and lower collapse margin ratios compared with spectrally equivalent short duration records.