Civil Engineering - Soil Mechanics and Foundation Engineering - Discussion

Discussion Forum : Soil Mechanics and Foundation Engineering - Section 2 (Q.No. 23)
23.
For a homogeneous earth dam 50 m high having 2 m free broad, a flow net was constructed and the results were : Number of potential drops = 2.4 Number of flow channels = 0.4. If coefficiency of permeability of the dam mateiral is 3 x 10-3 cm3/sec, the discharge per metre length of dam, is
12 x 10-5 m3/sec
24 x 10-3 m3/sec
6 x 10-5 m3/sec
24 x 10-5 m3/sec
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
22 comments Page 1 of 3.

Abhesh kumar yadav said:   2 years ago
Number of potential drops = 2.4,
Number of flow channels = 0.4.
Coefficient of permeability of the dam material = 3 x 10^-3 cm^3/sec.
Height of the dam = 50 m.
Freeboard of the dam = 2 m.

Calculations:
Head loss, h = 50 m - 2 m = 48 m.
Discharge per meter length of the dam, Q = kh * (Nf/Nd).
= (3 x 10^-3 cm^3/sec) * 48 m * (0.4/2.4).
= 24 x 10^-5 m^3/sec.
Therefore, the discharge per meter length of the dam is 24 x 10^-5 m^3/sec.
(4)

Dipak singh said:   4 years ago
How q=kh (hf/nd)? Please prove it.
(3)

Hadiul Islam said:   4 years ago
Given data,


K = 3*10^-3cm3/sec.
(0.003/100) = 0.00003 m3/sec, OR.
3*10^-5m3/sec.

H = (50 -2 ) 48 m.
Nf = .4,
Nd = 2.4,

Then formula;
Q = kh* (Nf/Nd).

Q = .00003 * 48 * (.4/2.4)
Q = 0.00024 OR 24*10^-5 m3/sec.
(2)

Siddhant Subedi said:   2 years ago
The value of the coefficient of permeability = 3x10^-3 cm/s not cm^3/s.
(1)

Atem Akech Atem said:   4 years ago
How q=k.h/Nd.Nf? Prove it.
(1)

Er Amit Kumar said:   5 years ago
Given data,
K = 3*10^-3cm3/sec
(0.003/100) = 0.00003 m3/sec, OR
3*10^-5m3/sec.

H = (50 -2 ) 48 m.
Nf = .4
Nd = 2.4
Than formula,
Q = kh* (Nf / Nd)

Q = .00003 * 48 * (.4 / 2.4
Q = 0.00024 OR 24*10^-5 m3/sec.
(1)

Mayur said:   7 years ago
Thank you all for explaining this.

Keeda said:   5 years ago
Unit of K is cm/sec.

Jessica said:   6 years ago
Thank you All for explaining.

Sushma Thota said:   7 years ago
The discharge PER METER is asked, so the calculated answer must be divided by 100
since 1m=100cm.

So, the given units and given answer are correct.


Post your comments here:

Your comments will be displayed after verification.