Office Complexes/High Tech : Cal Trans Headquarters - District 4 Structural Retrofit Studies   1 The Caltrans District 4 Headquarters is a 15-story, steel moment-resisting frame building that provides office space for approximately 2,000 Caltrans employees, a fleet of Caltrans vehicles, and the Bay Area Transportation Management Center. Crosby Group, teamed with Degenkolb Engineers, was retained to provide an initial study to identify four possible upgrade schemes and implement the approved scheme. Our solution includes strengthening 60% of the moment-resisting frame connections and installing viscous dampers (energy dissipation devices) in 115 bays. This scheme met the client's needs considering cost, construction impact, staff disruptions, etc. Copyright © 2002-2005 The Crosby Group. All Rights Reserved. Design by Global 1 Design.