A challenge arising from a parking structure (built partially above ground due to water-table problems) gave way to an elegant and iconic solution utilizing diagonal bracing offset from a glass curtain wall. This design maximized usable interior space while minimizing columnar interference with the existing parking structure.
The 25-story tower is set astride a three-level public garage at the southern end of the Golden Gateway Center, a residential and commercial development near the waterfront. The garage roof with the entrance lobby is two stories above street level and features a handsomely landscaped plaza with a large fountain and four sunken gardens. Connection to the street level is provided by four open flights of stairs and a set of escalators.
The design of the tower’s steel framework was governed by the desire to find the most economical solution of preventing damage caused by seismic forces. The external members are placed 18 inches outside the curtain wall facade. The only members rising directly from the ground are the main columns, which are spaced at 50 feet while the intermediate columns and the diagonal bracing end above the entrance floor. The external members and curtain wall framing are clad in bronze anodized aluminum.