Hydro-Mechanical Properties of an Unsaturated Frictional Material

2.5. CONSTITUTIVE MODELS FOR HYDRAULIC FUNCTIONS 51
Fraction of frustums µ: The fraction of frustums µ only influences the drainage process.
During the drainage process the larger frustum-shaped pores are draining first while the
smaller pores still remain water. With increasing µ the residual degree of saturation Sr
is increasing for the corresponding residual suction ψr (see Fig. 2.26).
0.2 0.4 0.6 0.8 1.0
0.0
x=0.3 ξ
x=0.5 ξ
x=0.8 ξ = 0.3 0.5 = 0.8
10 100 Suction (kPa) 1 0.1
(-)
Figure 2.25: Influence of the parameter ξ on the shape of the soil-water characteristic curve
Saturation
1.0
m μ = 0.07
m μ = 0.1 0.2 = m = 0.2
μ =
0.2
0.6 0.07 0.1 0.8
0.4
10 100 1 0.1 0.0
Saturation (-)
Figure 2.26: Influence of the parameter µ on the shape of the soil-water characteristic curve
(kPa) Suction