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by R. Darragh,
M. Huang and
A. Shakal
Click on the link below for the full text:
Introduction
Important data for geotechnical engineering was recorded at the joint
CSMIP/National Science Foundation (NSF) Treasure Island Geotechnical Array
near San Francisco. Low-amplitude accelerograms were recorded at the array
from a distant ML 5.3 earthquake. The earthquake occurred near Gilroy,
approximately 120 km away. In this soft-soil site-response array
accelerometers are installed at the surface and in 5 nearby boreholes. The
borehole accelerometers are located below the sandstone and shale bedrock
surface (104 m) and at 4 intermediate locations in the soil profile (7, 16,
31, 44 m).
The peak acceleration, velocity and displacement at the array are 0.0142 g,
0.86 cm/sec and 0.08 cm, respectively. These peaks were recorded on channel
1, located on the surface in the north-south direction. In the north-south
direction, peak acceleration ranged from 0.0032 g in bedrock to 0.0142 g at
the surface. In the east-west direction, peak accelerations of 0.0024 and
0.0133 g were recorded in bedrock and at the surface, respectively. In
contrast, on the vertical component the peak acceleration ranged from 0.0021 g
in bedrock to 0.0044 g at the surface. The processing of these records
occurred in parallel with digitization and processing of many large amplitude
records from the Landers earthquake.
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