# Dry Unit Weight

Written by Jerry Ratzlaff on . Posted in Geotechnical Engineering

Dry unit weight, abbreviated as $$\gamma_d$$, is the ratio of the weight of soil to the volume of soil or when the soil voids are filled with air and no water.

## Dry Unit Weight formulas

 $$\large{ \gamma_d = \frac{ W_s }{ V_t } }$$ $$\large{ \gamma_d = \frac{ G_s \; \gamma_w }{ V_t } }$$ $$\large{ \gamma_d = \frac{ G_s \; \gamma_w }{ e \;+\;1 } }$$ $$\large{ \gamma_d = \frac{ Y }{ 1 \;+\; w } }$$

### Where:

$$\large{ \gamma_d }$$  (Greek symbol gamma) = dry unit weight

$$\large{ Y }$$ = bulk density

$$\large{ G_s }$$ = specific gravity of soil

$$\large{ \gamma_w }$$  (Greek symbol gamma) = unit weight of water

$$\large{ e }$$ = void ratio

$$\large{ V_t }$$ = total volume of soil

$$\large{ w }$$ = water content

$$\large{ W_s }$$ = weight of soil