Soil Unit Weight from Specific Gravity Calculator

What this calculation does not cover

• Dry and saturated are the two end states of the same soil, and the calculator has no water content field, so it never gives the moist (field) unit weight the ground actually has. That is the dry unit weight times (1 + w), and a compaction report's dry density carried straight into an earth pressure, overburden or haul weight check leaves the pore water out of the load.
• The saturated figure assumes every void is completely filled with water. Ground above the water table and a partially saturated fill weigh less than this, and the buoyant (submerged) unit weight that effective stress work below the water table is built on is not printed — you subtract the unit weight of water from the saturated value yourself.
• The specific gravity field accepts 2.4 to 2.9 and the void ratio field 0.2 to 3, and a value outside those is replaced with the nearest limit rather than refused. Peat and organic soils sit below the specific gravity floor and above the void ratio ceiling, and iron-rich soils, slag and heavy mine tailings sit above the specific gravity ceiling, so for those materials the answer shown belongs to the substituted value, not to the one you entered.
• Both inputs describe one specimen at one point. A borehole log gives different phase properties stratum by stratum and a fill varies across its lifts, so this returns a single unit weight rather than the layer-by-layer profile that vertical stress and effective stress calculations are assembled from.
• This is a phase relationship, not a soil test and not a design value. It does not check that the specific gravity and void ratio came from the same specimen or are physically consistent, applies no factor of safety, and returns a number for any pair typed in; characterising ground for bearing, settlement or earth pressure design stays with a geotechnical engineer working from an actual investigation.