18.104.22.168 Preliminary Screening
All welded steel moment frame structures shall undergo a detailed frame joint evaluation if the building is located at a site that has experienced the following:
- An earthquake of magnitude greater than or equal to 6.5 that produced ground motion in excess of 0.20 g; or
- An earthquake that generated ground motion in excess of 0.30 g.
The ground motion estimates shall be based on actual instrumental recordings in the vicinity of the building. When such ground motion records are not available, ground motion estimates may be based on empirical or analytical techniques. All ground motion estimates shall reflect the site-specific soil conditions.