Thirty-nine high rises in San Francisco are at risk of collapse in a major earthquake, according to a new study by the U.S. Geological Service (USGS).
The vulnerable buildings (known as welded steel moment-frame buildings) were constructed by using a flawed technique to weld columns and beams together. This technique was found to be less resilient to seismic activity after the 1994 Northridge earthquake in Los Angeles where critical joints were damaged in several buildings that had been welded.
The building code was revised in the mid-1980s to require more stiffness, and then again in the mid-1990s to correct the defective welding technique. San Francisco outlawed the technique in1994 after damage from the Northridge quake on high rises was discovered. The list of vulnerable structures includes the former Bank of America building, the headquarters of Pacific Gas and Electric, three hotels, and the Salesforce West tower.
San Francisco has offered incentives to repair at-risk buildings. In 2009, the city expedited permits and agreed to waive fees for so-called “soft-story buildings” that have garages or windows on the bottom floor.
Related Stories
Codes and Standards | Jul 17, 2018
NIMBYism, generational divide threaten plan for net-zero village in St. Paul, Minn.
The ambitious redevelopment proposal for a former Ford automotive plant creates tension.
Codes and Standards | Jul 17, 2018
In many markets, green features are more of a requirement for apartment renters
Renters in many U.S. cities have come to expect green features in apartments that they rent, with an eye toward energy efficiency and healthy indoor air.
Codes and Standards | Jul 16, 2018
Length of North American construction disputes continues to increase
They already far exceed global average.
Codes and Standards | Jul 12, 2018
Developer says net zero Salt Lake City apartment high-rise built at standard cost
Off-site solar, and mechanical/electrical system savings aid the achievement.
Codes and Standards | Jul 11, 2018
D.C. local worker requirement not being met
Government doing little to verify self-reported project data.
Codes and Standards | Jul 10, 2018
Carbon emissions in cement production threaten GHG reduction goals
Cement is essential to many infrastructure projects that address climate change.
Codes and Standards | Jul 10, 2018
DOE’s Better Buildings Summit to be held in Cleveland, August 21-23
Agenda includes technical training and networking opportunities.
Codes and Standards | Jul 6, 2018
Houston’s lessons learned from Harvey include lack of awareness by residents of flood danger
Inconsistent regulatory environment also cited.
Codes and Standards | Jul 6, 2018
Delos and HDR will co-develop wellness design tools and collaborate on research
WELL Building Standard pioneer teams with architects to advance wellness innovations in the built environment.
Codes and Standards | Jul 5, 2018
BREEAM New Construction standard launched in U.S.
Follows successful launch of BREEAM In-Use standard.