Napa Valley assesses impact of structural retrofits on buildings after earthquake

About 30 inspection teams of two inspectors each have conducted at least quick exterior inspections of downtown Napa, Calif., buildings since a magnitude 6.0 earthquake struck the region. More than 150 buildings in the area have been declared unsafe to occupy.Nonductile concrete buildings and those made of brick or stone appear to have suffered the most damage.

Some city officials said it’s too early to fully determine the effectiveness of years of earthquake preparedness and structural retrofitting. More comprehensive structural inspections have yet to be conducted.

Some reports have indicated that seismic retrofit work did save some buildings, though. One inspector told the local Press Democrat newspaper that about 15 buildings he inspected did have seismic retrofitting and were still standing.

Another inspector said that although retrofitted buildings were damaged, structural steel added to interiors saved some from destruction.

(http://www.pressdemocrat.com/home/2587291-181/teams-of-inspectors-start-assessment)