The Infiltration Numerical Simulation for Several Kinds of Unsaturated Soil under Rainfall Condition - Advanced Research on Computer Education, Simulation and Modeling - page 246

Water content

0.0 0.1 0.2 0.3 0.4

T=6min

20 T=60min

T=120min

40

60

Fig. 1. Evolution with time of bulk water along depth direction

5.4

3.6

1.8

0

0 30 60 90 120 150 180

Time (min)

Fig. 2. Evolution with time of computed infiltration rate

decrease slowly soon after. Water accumulation appears at about 60min. Evolution
with time of bulk water along depth direction is shown in Fig.1. The evolution of
wetting front could also be seen from this figure.
Evolution with time of computed infiltration rate is shown in Fig.2. It could be
seen that the infiltration is 5.0cm/h, and it is consistent with rainfall intensity.

4.2 Infiltration Process of Silt Clay and Clay Column

The rainfall intensity is given as 5.0cm/h, and the rainfall duration is 180minutes.
Calculation results show that the soil suctions decrease rapidly at the beginning, then
decrease slowly soon after. Water accumulation appears at about 30min. Evolution
with time of bulk water along depth direction is shown in Fig.3. The evolution of
wetting front could also be seen from this figure. It could be seen that wetting front is
sharper than silt clay column. The Infiltration process of clay column is similar with
Fig.3, but wetting front is sharpest of them.