NCEER (1997) based on Seed & Idriss (1971)
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rd= 1.0 - 0.00765 Z
rd= 1.174 - 0.0267 Z
rd= 0.744 - 0.008 Z
rd= 0.50
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for z ≤ 9.15 m
for 9.15 m < z ≤ 23 m
for 23 m < z ≤ 30 m
for z > 30 m
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Thomas F. Blake (FugroWest Inc., Ventura, California)
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Idriss & Boulanger (2008)
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(based on Golesorkhi 1997 and Idriss 1999 works)
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Kayen et al. (1992)
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rd = 1 - 0.012 Z
|
|