A Near-Fault Design Spectrum and Its Drift Limits

The improvement of structural capacity against large displacement demand of near-fault ground motions has become the subject of research for the last decade. Parallel to the developments in performance-based seismic design (PBSD) this issue has attracted researcher interest further, as assessment of structural displacement capacity has become one of the main issues for the procedures employed in this new concept. This study focuses on the near-fault ground motion demand. We have used soil site, near-field records from various M>6.5 events including the 1999 Turkey and Taiwan earthquakes. The spectral quantities were computed through an attenuation relationship that is based on these near-fault ground motion records. The derived spectral quantities were evaluated for the global displacement demand definition of such ground motions. We employ this global demand definition to calculate the distance and magnitude dependent inter-story drift demand limits for frame-type structures. We compare our findings with the Uniform Building Code provisions.