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 | Dec 9, 2020
Newly formed Rainscreen Association aims to be recognized authority on rainscreen assemblies
Will address innovations in material performance and building designs.
Codes and Standards | Dec 9, 2020
Investors want building resiliency plans and risk mitigation practices
Owners should assess risk, insurance coverage, and ability to withstand disasters.
Codes and Standards | Dec 4, 2020
OSHA cites more than 200 employers for COVID-19 violations
Agency releases guidance on lessons learned from pandemic inspections.
Codes and Standards | Dec 1, 2020
Pandemic spurs nearly 16 million people to move from major cities
Most of the movement seems permanent.
Codes and Standards | Nov 30, 2020
USGBC ready to catalyze LEED Positive future
New programs, updates will spur shift to regenerative strategies.
Codes and Standards | Nov 30, 2020
Updated spec for self-adhering flashing surrounding exterior fenestration products released
FGIA document was last updated in 2013.
Codes and Standards | Nov 30, 2020
Finalized 2021 Energy Code leaves out future-proofing provision
Appeals process nixed requirement for residential electrification readiness.
Codes and Standards | Nov 23, 2020
GBCI turns over GRESB ownership to global investment firm
Organization assesses sustainability performance of real estate and infrastructure portfolios and assets.
Codes and Standards | Nov 23, 2020
New industrywide clay brick EPD launched
Contributes toward LEED v.4.0 and v.4.1 materials and resources requirements.
Codes and Standards | Nov 19, 2020
The ‘15-minute city’ could transform municipal planning
Concept aims for car-free living.
