Practice Question: Total Unit Weight of Soil Based on Parameters

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Solution

We can calculate specific gravity based on the weight and volume of solids:
\[G_s= \frac{W_s}{V_s γ_w }= \frac{10 lb}{100 in^3×\frac{1}{(12 in)^3} ×62.4 pcf}=2.77\]

We can calculate total unit weight based on water content, specific gravity, and void ratio:
\[γ_t= \frac{(1+w) G_s γ_w}{1+e}\]

\[γ_t= \frac{(1+0.2)×2.77×62.4 pcf}{1+0.66}≈125 pcf\]

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