• Napa Earthquake - Results

• Strong shaking in epicentral area, low-level shaking throughout Bay area

• Recorded strong motion:• 340 ground response

stations• 70 structures• 14 geotechnical arrays• 3000 data channels

available from CESMD, StrongMotionCenter.org

CISN and Earthquake Engineering Progress

PGA vs Rjb Distance

• BA08 (Boore-Atkinson, 2008

• Strike-slip• Vs30 = 760

m/s

Geotechnical Downhole Arrays• Records from 14 arrays (Caltrans

supported)• Two arrays with strong shaking

Surface

67 ft

150 ft

E-W

N-S

Vert

(Pile Tip Sensors)

(Tilt Sensor)

North End

South End

Tilt

• First strong shaking in Bay area since Loma Prieta, 1989

• Many more sites and structure instrumented now:• All major toll bridges (Caltrans supported)• 15 high rise buildings• Many ground stations (both CGS and USGS), CISN stations

• Significant new data• 400+ strong motion records vs ~200• Brought together in StrongMotionCenter.org

South Napa Earthquake of 2014