What is Relative Compaction?

Relative compaction is a ration of the density of soil at site to the maximum dry density of soil.

like we have maximum dry density of soil have 1800 kg/m3 which determine in lab

now on site we can archive 1700 kg/m3 by compaction of dumped soil

so relative density of that soil on site is =1700/1800=0.9444 = 94.44%

it is use for

1. to know how much density we archive compare to design in lab
2. sometime in specification minimum criteria of relative density are given, ex- minimum relative density at whole site should be 90%.
3. from relative density we can calculate actual movement of soil, which is very important in tall building and structural durability calculation