Related Resources: civil engineering

Soil Cohesion Table

Civil Engineering and Design Resources

Soil Cohesion is the component of shear strength of a rock or soil that is independent of interparticle friction. In soils , true cohesion is caused by following: Electrostatic forces in stiff overconsolidated clays (which may be lost through weathering)

Typical soil cohesion values for different soils

The soil cohesion depends strongly on the consistence, packing, and saturation condition. The values given below correspond to normally consolidated condition unless otherwise stated. These values should be used only as guidline for geotechnical problems; however, specific conition of each engineering problem often needs to be considered for an appropriate choice of geotechnical parameters.

Description	Cohesion [kPa]
	min	max	Nominal
Well graded gravel, sandy gravel, with little or no fines	-	-	0
Poorly graded gravel, sandy gravel, with little or no fines	-	-	0
Silty gravels, silty sandy gravels	-	-	0
Clayey gravels, clayey sandy gravels	-	-	20
Well graded sands, gravelly sands, with little or no fines	-	-	0
Poorly graded sands, gravelly sands, with little or no fines	-	-	0
Silty sands	-	-	22
Silty sands - Saturated compacted	-	-	50
Silty sands - Compacted	-	-	20
Clayey sands	-	-	5
Clayey sands - Compacted	-	-	74
Clayey sands -Saturated compacted	-	-	11
Loamy sand, sandy clay Loam - compacted	50	75
Loamy sand, sandy clay Loam - saturated	10	20
Sand silt clay with slightly plastic fines - compacted	-	-	50
Sand silt clay with slightly plastic fines - saturated compacted	-	-	14
Inorganic silts, silty or clayey fine sands, with slight plasticity	-	-	7
Inorganic silts and clayey silts - compacted	-	-	67
Inorganic silts and clayey silts - saturated compacted	-	-	9
Inorganic clays, silty clays, sandy clays of low plasticity	-	-	4
Inorganic clays, silty clays, sandy clays of low plasticity - compacted	-	-	86
Inorganic clays, silty clays, sandy clays of low plasticity - saturated compacted	-	-	13
Mixture if inorganic silt and clay - compacted	-	-	65
Mixture if inorganic silt and clay - saturated compacted	-	-	22
Organic silts and organic silty clays of low plasticity	-	-	5
Inorganic silts of high plasticity - compactd	-	-	10
Inorganic silts of high plasticity - saturated compacted	-	-	72
Inorganic silts of high plasticity	-	-	20
Inorganic clays of high plasticity	-	-	25
Inorganic clays of high plasticity - compacted	-	-	103
Inorganic clays of high plasticity - satrated compacted	-	-	11
Organic clays of high plasticity	-	-	10
Loam - Compacted	60	90
Loam - Saturated	10	20
Silt Loam - Compacted	60	90
Silt Loam - Saturated	10	20
Clay Loam, Silty Clay Loam - Compaced	60	105
Clay Loam, Silty Clay Loam - Saturated	10	20
Silty clay, clay - compacted	90	105
Silty clay, clay - saturated	10	20
Peat and other highly organic soils	-	-

References

• Swiss Standard SN 670 010b, Characteristic Coefficients of soils, Association of Swiss Road and Traffic Engineers
• Minnesota Department of Transportation, Pavement Design, 2007
• NAVFAC Design Manual 7.2 - Foundations and Earth Structures,SN 0525-LP-300-7071, REVALIDATED BY CHANGE 1 SEPTEMBER 1986