GATE Civil Engineering (CE) 2018 Shift 2 Solved Paper

Question : 44 of 65

Marks: +1, -0

Three soil specimens (Soil 1, Soil 2 and Soil 3 ), each

150 {mm}

long and

100 {mm}

diameter, are placed in series in a constant head flow set-up as shown in the figure. Suitable screens are provided at the boundaries of the specimens to keep them intact. The values of coefficient of permeability of Soil 1, Soil 2 and Soil 3 are

0.01,0.003

and

0.03 {cm} {/} {s}

, respectively.

The value of

h

in the set-up is

$0 {mm}$
$40 {mm}$
$255 {mm}$
$560 {mm}$

Validate

Solution:

In normal to bedding plane flow (series arrangement), Discharge will be same and Head loss and Hydraulic gradient will be different.

q=K_{1} i_{1} A=K_{2} i_{2} A=K_{3} i_{3} A=K_{ang} ⋅(\;{H_{L}}/{L}) A

K_{\;\text "avg "\; 1}=\;{Σ Z_{1}}/{Σ \;{Z_{i}}/{K_{t}}}=\;{150+150+150}/{{150}/{0.01}+\;{150}/{0.003}+\;{150}/{0.03}}=0.0064

Total head loss

=H_{L}=560 {mm}

K_{3} ⋅ \;{h}/{150} × A=K_{\;\text "avg "\;} ⋅ \;{560}/{(150+150+150)} A

0.03 ⋅(\;{h}/{150})=00064(\;{560}/{450})

h=40 {mm}

Go to Question:

Prev Question

Next Question