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 | Oct 7, 2020
More energy efficiency programs are encouraging zero-energy projects
At least 20 programs for new construction, major renovations emerge.
Codes and Standards | Oct 6, 2020
LEED, GBCI rating systems spur resilience-enhancing strategies
Expanded programs, resources address impact of climate change.
Codes and Standards | Oct 6, 2020
International Code Council to hold inaugural online education event
Week-long ICC Learn Live will include panel conversations, keynotes, and breakout sessions around key topics in building safety.
Codes and Standards | Oct 5, 2020
Guides addressing fenestration anchorage updated
First update to decade-old technical documents released.
Codes and Standards | Oct 1, 2020
Deadline extension for LEED 2009 project certifications
Delivery timeline delays due to COVID-19 pandemic prompt action.
Codes and Standards | Sep 29, 2020
New drinking water standard criteria further restricts lead leaching in plumbing products
Tightened standard applies to endpoint devices that dispense drinking water, and other plumbing components
Codes and Standards | Sep 29, 2020
Groups sue CDC over eviction moratorium
Natl. Apartment Assn. and New Civil Liberties Alliance want hearing by October.
Codes and Standards | Sep 24, 2020
Benefits of building enclosure commissioning include reduced costs
Savings achieved in less rework and fewer and shorter punch lists.
Codes and Standards | Sep 23, 2020
Intl. Code Council aims to stay ahead of new tech, efficiency trends, and resiliency
Passive survivability, social resiliency, and community health among the goals.
Codes and Standards | Sep 22, 2020
Air cleaners, chemical and UV treatments among tools to safeguard indoor air amid pandemic
Strategies augment social distancing, increased air flow to combat COVID-19 spread.
