Investigators for San Francisco’s Transbay Joint Powers Authority are searching for the cause of brittle fractures in the tapered bottom flanges of twin 80-ft-long built-up plate girders in San Francisco’s Salesforce Transit Center.
Gov. Jerry Brown (D) in late September vetoed a bill that would have directed California municipalities to create a database of structures that would be at risk of collapse as a result of seismic events.
The Transbay Joint Powers Authority, after closing its recently dedicated Salesforce Transit Center, is investigating the cause of cracked built-up plate girders supporting the roof garden.
The 58-story Millennium Tower in the Transbay district of San Francisco, which has sunk 18 in. and is tilting 2 in., is under even more scrutiny for possible structural defects since a window on the 36th floor cracked.
While widely accepted in Europe, designers and builders in the U.S. have struggled to take full advantage of mass timber because of current limitations in prescriptive codes.
To handle the massive scale of this $1-billion, 3.8-million-sq-ft mixed-use project, the multinational and multifirm construction teams split the project into two phases designed and built concurrently.
Completed in April in New York City, this 12-story condominium building stands out with its curvaceous metal exoskeleton—fabricated in Italy—in a design that incorporates architecture, art and technology.