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  1. A non-homogeneous soil deposit consists of a silt layer sandwiched between a fine-sand layer at top and a clay layer below.
    Permeability of the silt layer is 10 times the permeability of the clay layer and one-tenth of the permeability of the sand layer.
    Thickness of the silt layer is 2 Times the thickness of the sand layer and two-third of the thickness of the clay layer. The ratio of equivalent horizontal and equivalent vertical permeability of the deposit is ________.
    1. 11.0254
    2. 10.9675
    3. 10.0056
    4. 9.6542
Correct Option: B

Given, k2 = 10 k3 and k2 = 1/10 k1
d2 =2d1 and d2 = 2/3 d3
∴ k1 = 10k2, k3 = 1/10 k2
d1 = 1/2 d2,d3 = 3/2 d2

kH =
k1d1 + k2d2 + k3d3
d1 + d2 + d3

=   (10k2 ×
1
d2) + k2d2 +
1
k2 ×
3
d2
2102
1
d2 + d2 +
3
d2
22

=
k2d2
(5 + 1 + 3/20)
d23

= k2 ×
123
= 2.05 k2
60



=
60
k2 = 0.187 k2
321

kH
=
2.05k2
= 10.9675
kV0.187k2



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