Units and Symbols - Unsaturated Soil Mechanics in Engineering Practice - page 860

Table A.4 List of Symbols

Description Symbol Unit

Absolute air pressure u a kPa

Absolute temperature T K K

Actual evaporation AE mm/day

Air-entry bubbling pressure u b kPa

Air-entry suction ψ aev kPa

Air pressure u a kPa

φ b

Angle indicating rate of shear strength change with
respect to suction

degree

Atmospheric pressure u atm kPa

Average molecular weight of air ω a g/mol

Axial (vertical) strain ε a %

σ ij Bishop's average soil skeleton stress kPa

χ

Bishop stress parameter decimal

Capillary height h c m

Capillary meniscus curvature R s m

Coefficient of active earth pressure K a —

Coefficient of air permeability k a m/s

c v

m 2 /s Coefficient of consolidation for air phase

c v m 2 /s Coefficient of consolidation for water phase

m 2 /s Coefficient of diffusion D

Coefficient of earth pressure at rest K 0 —

Coefficient of passive earth pressure K p —

Coefficient of permeability at saturation k s m/s

Coefficient of water permeability k w m/s

m 1 Coefficient of air volume change with respect to net

normal stress

1/kPa

m 2

Coefficient of air volume change with respect to soil
suction

1/kPa

m 1 Coefficient of soil structure volume change with respect to

net normal stress

1/kPa

m 2 Coefficient of soil structure volume change with respect to

soil suction

1/kPa

m 1

Coefficient of water volume change with respect to net
normal stress

1/kPa

m 2

Coefficient of water volume change with respect to soil
suction

1/kPa

Coefficient of volume change of saturated soil m v 1/kPa

Compressibility of water c w 1/kPa

Contact angle α degrees

Degree of saturation S %

kg/m 3

Density of air ρ a

kg/m 3

Density of any fluid ρ f

kg/m 3

Density of water ρ w

kg/m 3

Density of soil particles ρ s

kg/m 3 Density of water with salts ρ ws

Deviator stress σ 1 − σ 3 kPa

o C

Dew-point temperature t d

Diameter of 10% passing D 10 mm

Diameter of 50% passing D 50 mm