Consider the following hydraulic structure being constructed on sand:

The uplift pressure at point A is __________ kN/m $^{2}$ .
[Use Bligh's creep theory and take $γ_{w} = 10 k N / m^{3}$ ]

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Solution

The correct option is B 20
Length of creep
$= 2 \times 5 + 2 + 2 \times 4 + 5 + 10 + 2 \times 5$
$= 50 m$

$∴ Hydraulic gradient = \frac{5}{50} = \frac{1}{10}$

Now, length of creep upto point A
$= 2 \times 5 + 5 + 2 + 2 \times 4 + 5 = 30 m$

$∴$
Unbalanced head atA
$h = 5 (1 - \frac{30}{50}) = 2 m$

$∴$
Uplift pressure at A
$= γ_{w} h = 10 \times 2 = 20 k N / m^{2}$

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Similar questions

Q. Consider the following hydraulic structure being constructed on sand:

The uplift pressure at point A is __________ kN/m

^{2}

.
[Use Bligh's creep theory and take

γ_{w} = 10 k N / m^{3}

]

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Consider the following hydraulic structure being constructed on sand: The uplift pressure at point A is __________ kN/m2. [Use Bligh's creep theory and take γw=10kN/m3]

The correct option is B 20Length of creep =2×5+2+2×4+5+10+2×5 =50m ∴Hydraulic gradient=550=110 Now, length of creep upto point A =2×5+5+2+2×4+5=30m ∴ Unbalanced head atA h=5(1−3050)=2m ∴ Uplift pressure at A =γwh=10×2=20kN/m2

Consider the following hydraulic structure being constructed on sand:

The uplift pressure at point A is __________ kN/m $^{2}$ .
[Use Bligh's creep theory and take $γ_{w} = 10 k N / m^{3}$ ]