# Porosity

on . Posted in Geotechnical Engineering

Porosity, abbreviated as n, a dimensionless number, is the ratio between the pore volume of a substance and its total volume.  Porosity of a measure of a rocks capacity to store fluids.

## Porosity formula

$$\large{ n = \frac {V_v} {V_t } }$$
Symbol English Metric
$$\large{ n }$$ = porosity $$\large{dimensionless}$$
$$\large{ V_t }$$ = total volume of soil $$\large{ft^3}$$ $$\large{m^3}$$
$$\large{ V_v }$$ = volume of voids (air and water) $$\large{ft^3}$$ $$\large{m^3}$$