kgf/m³

kilogram-force per cubic meter

Unit weightexact by definition

The kilogram-force per cubic metre is exactly 9.80665 N/m³. It is the gravitational-system form of unit weight, numerically equal to density in kg/m³, which is exactly why gravitational units survived so long in geotechnical practice: the same number serves for both.

Watch out: That numerical coincidence is the trap. Soil at 1800 kg/m³ has a unit weight of 1800 kgf/m³ and of 17.66 kN/m³, and an equation written for kN/m³ fed the number 1800 is wrong by a factor of 100.

1 kgf/m³ 0.00980665 kN/m³