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
| Oct 18, 2011
Dow Building Solutions invests in two research facilities to deliver data to building and construction industry
State-of-the-art monitoring system allows researchers to collect, analyze and process the performance of wall systems.
| Oct 14, 2011
ACI partners with CRSI to launch new adhesive anchor certification program
Adhesive anchor installer certification required in new ACI 318-11.
| Oct 13, 2011
New Building Materials Label Focuses On Sustainability
Architectural products company Construction Specialities and design firm Perkins + Will have created a label for building materials to shed light on product content.
| Oct 13, 2011
New Law: California Building Standards Commission Must Include Green Expert
A new California law, AB 930, requires that one member of the California Building Standards Commission be “experienced and knowledgeable in sustainable building, design, construction, and operation.”
| Oct 13, 2011
AGC Urges Repeal of 3% Withholding On Government Contracts
The U.S. House of Representatives is planning a vote in October on a bill to repeal the 3% withholding requirement on all federal and state contracts for goods and services.
| Oct 13, 2011
House Bill Would Block New OSHA Regulations
Proposed riders in a U.S. House of Representatives spending bill would block the Occupational Safety and Health Administration (OSHA) from issuing controversial workplace safety and health regulations.
| Oct 11, 2011
AIA introduces five new documents for use on sustainable projects
These new documents will be available in the first quarter of 2012 as part of the new AIA Contract Documents service and AIA Documents on Demand.
| Oct 7, 2011
GREENBUILD 2011: UL Environment releases industry-wide sustainability requirements for doors
ASSA ABLOY Trio-E door is the first to be certified to these sustainability requirements.
| Oct 6, 2011
Taking tenant behavior into account on building energy codes
Over the past few years, Seattle, San Francisco, Austin, and Washington, D.C., have passed laws requiring property owners to measure and disclose their energy use, which would help place a market value on a building’s efficiency and provide a benchmark for improvements.
| Oct 6, 2011
Constructed properly, green roofs hold up well in a hurricane
The heavy rains and high winds of Hurricane Irene didn’t cause any problems for a Con Edison green roof in New York City. The roof contains sedum, a plant that adapts well to drought and handles periods of heavy rain well.
