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where 𝜏max is the maximum earthquake induced shear stress,
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For this example,
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Per WsDOT WSDOT BDM section 8.3.4B, the ground acceleration (PGA) can be reduced according to the depth of fill. The ground motion attenuation is shown in table 1 (below). For a fill of 16', the ratio of ground motion to motion at burried structure is 1.0.
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Summing these forces gives a total dead load of 2.27 klf
From WsDOT WSDOT BDM section 8.3.4B, the ground motion attenuation ration of 0.9 is applied since the depth of fill is within the range of 20' to 50'.
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